Abstract
Aims
Research shows persistent ethnic inequities in mental health experiences and outcomes, with a higher incidence of illnesses among minoritised ethnic groups. People with psychosis have an increased risk of multiple long-term conditions (MLTC; multimorbidity). However, there is limited research regarding ethnic inequities in multimorbidity in people with psychosis. This study investigates ethnic inequities in physical health multimorbidity in a cohort of people with psychosis.
Methods
In this retrospective cohort study, using the Clinical Records Interactive Search (CRIS) system, we identified service-users of the South London and Maudsley NHS Trust with a schizophrenia spectrum disorder, and then additional diagnoses of diabetes, hypertension, low blood pressure, overweight or obesity and rheumatoid arthritis. Logistic and multinomial logistic regressions were used to investigate ethnic inequities in odds of multimorbidity (psychosis plus one physical health condition), and multimorbidity severity (having one or two physical health conditions, or three or more conditions), compared with no additional health conditions (no multimorbidity), respectively. The regression models adjusted for age and duration of care and investigated the influence of gender and area-level deprivation.
Results
On a sample of 20 800 service-users with psychosis, aged 13–65, ethnic differences were observed in the odds for multimorbidity. Controlling for sociodemographic factors and duration of care, compared to White British people, higher odds of multimorbidity were found for people of Black African [adjusted Odds Ratio = 1.41, 95% Confidence Intervals (1.23–1.56)], Black Caribbean [aOR = 1.79, 95% CI (1.58–2.03)] and Black British [aOR = 1.64, 95% CI (1.49–1.81)] ethnicity. Reduced odds were observed among people of Chinese [aOR = 0.61, 95% CI (0.43–0.88)] and Other ethnic [aOR = 0.67, 95% CI (0.59–0.76)] backgrounds. Increased odds of severe multimorbidity (three or more physical health conditions) were also observed for people of any Black background.
Conclusions
Ethnic inequities are observed for multimorbidity among people with psychosis. Further research is needed to understand the aetiology and impact of these inequities. These findings support the provision of integrated health care interventions and public health preventive policies and actions.
Key words: comorbidity, ethnic disparities, ethnic inequalities, ethnicity, multimorbidity, schizophrenia
Introduction
Ethnic inequities1 in health have been reported (Sproston and Mindell, 2006; Nazroo et al., 2009; El-Sayed et al., 2011; Watkinson et al., 2021). For example, previous studies suggest a higher prevalence of obesity, hypertension and cardiovascular disease among Black people in the UK (Sproston and Mindell, 2006; Nazroo et al., 2009; El-Sayed et al., 2011; Schofield et al., 2011) and higher risk of diabetes has been observed among people of Black Caribbean, Indian, Pakistani, Bangladeshi and Chinese background (Nazroo et al., 2009). Evidence suggests Black and South Asian people have an earlier onset of the majority of illness (Kuan et al., 2019) and the prevalence of multiple long-term conditions (MLTC, or multimorbidity) is observed to be higher in almost all minoritised ethnic groups in the UK (Mathur et al., 2011; Bisquera et al., 2021; Watkinson et al., 2021). Also, health-related quality of life and self-rated health, a predictor of mortality, is poorer in several minoritised ethnic groups (Evandrou et al., 2016; Watkinson et al., 2021).
Ethnic health inequities have been largely associated with differences in socioeconomic status (income, education, occupation) (Nazroo and Williams, 2006; Dubath et al., 2021). However, evidence suggests that ethnic inequities persist after controlling for socioeconomic factors, though such models may contain residual confounding (Nazroo, 1998; Nazroo and Williams, 2006; Evandrou et al., 2016; Larsen et al., 2017; Ashworth et al., 2019; Verest et al., 2019; Watkinson et al., 2021). Economic adversity is related to greater exposure to negative, stressful life events (Hatch and Dohrenwend, 2007), which in turn increase the odds of worse health and multimorbidity (Lin et al., 2021). Minoritised ethnic groups are also more likely to face discrimination which has been associated with worse mental and physical health conditions, including psychosis, diabetes and cardiovascular diseases (Karlsen and Nazroo, 2002; Harris et al., 2006; Paradies et al., 2015; Freitas et al., 2018; Pearce et al., 2019; Oh et al., 2021a). Negative, stressful events contribute to the dysregulation of physiological functions, affecting the stress response, the immune system and leading to bodily inflammation, all of which are related to ill health (McEwen, 1998; Beckie, 2012; Goosby et al., 2017; O'Connor et al., 2021). The disruption of bodily functions in response to stress was termed as allostatic load by McEwen (1998), and it represents the wear and tear of body. Adverse life events are also related to poorer health habits (e.g. poor sleep, substance use, lack of exercise) which can lead to the onset of health conditions (Halonen et al., 2014; Williams et al., 2019). Social disadvantage, as a whole, has also been identified as a key factor in the onset of psychosis and has been suggested to be a major explanatory factor for the higher prevalence of psychosis amongst ethnic minority groups and migrants in industrialised countries (Morgan et al., 2019; Jongsma et al., 2021a, 2021b; Bhui et al., 2021).
People with psychosis and other severe mental illness (SMI; such as bipolar) have an elevated risk of multiple long-term conditions (or multimorbidity), with higher incidence of diabetes, hypertension, asthma, chronic obstructive pulmonary disease and chronic kidney disease (Woodhead et al., 2014; Stubbs et al., 2016; Rodrigues et al., 2021). However, there is limited evidence on ethnic inequities in multimorbidity among people with psychosis. A recent study reported that people from a minoritised ethnic background show an increased risk of diabetes in the first year of psychotic illness, while no major changes were observed in White people (Gaughran et al., 2019). No ethnicity-related difference in overall weight (body mass index), or changes in it, were observed. However, increases in central obesity (mean waist circumference) were observed among minoritised ethnic women and White men, but no major changes were observed in minoritised ethnic men or White women (Gaughran et al., 2019). One meta-analysis of the side-effects of antipsychotics in metabolic function reported an association between a higher proportion of non-White ethnicity and greater increases in total cholesterol; however, no significant associations between ethnicity and change in weight, body max index (BMI), LDL cholesterol, HDL cholesterol, triglycerides and glucose were observed (Pillinger et al., 2020).
It is important to understand if people in minoritised ethnic groups, who show a higher risk for psychosis compared to their White British counterparts, also show an excessive risk for multimorbidity when living with psychosis. This raises questions about risks for multi-disease onset, and it has implications for preventive care. As mentioned above, studies show that exposure to chronic stress leads to increased allostatic load, which contributes to the onset of physical and mental health conditions (Beckie, 2012; O'Connor et al., 2021). Syndemic theory also suggests that co-occurrence of health conditions is fostered by conditions of poverty and social disadvantage and will lead to worse health outcomes (Singer et al., 2017). Thus, people living with mental and physical multimorbidity in conditions of social marginalisation may have a greater likelihood of intensive use of health care resources, worse quality of life and, potentially, reduced life expectancy (Das-Munshi et al., 2017, 2021; Kugathasan et al., 2020; Watkinson et al., 2021). To develop targeted preventive health interventions, it is important to identify if minoritised ethnic groups living with psychosis show worse physical health than their White British counterparts.
This study aims to investigate ethnic inequities in multimorbidity, and multimorbidity severity, among a cohort of people with psychosis. Acknowledging differences in multimorbidity related to gender (Larsen et al., 2017; Gaughran et al., 2019; Head et al., 2021; Watkinson et al., 2021) and socioeconomic deprivation (Marmot et al., 2020; Dubath et al., 2021; Head et al., 2021), we investigate interaction effects. We hypothesise that people of a minoritised ethnic background present higher multimorbidity than White British people and that this is amplified for minoritised ethnic women and minoritised ethnic people living in more deprived areas.
Method
Setting
This retrospective cohort study used data from the electronic health records (EHRs) of the South London and Maudsley (SLaM) National Health Service (NHS) Foundation Trust. SLaM's catchment area comprises four ethnically diverse London boroughs (Southwark, Lewisham, Lambeth and Croydon) covering 1.3 million people. Access to clinical records was obtained via the Clinical Record Interactive Search (CRIS) system (Stewart et al., 2009; Perera et al., 2016). CRIS was established under robust data protection and governance framework and received approval from the Oxford C Research Ethics Committee (18/SC/0372) to be used as a de-identified dataset for secondary data analysis (Stewart et al., 2009; Perera et al., 2016). Projects using CRIS are submitted for approval to a service-user led oversight committee; this project's reference is 20-075.
At the time of writing, CRIS enabled access to the de-identified information, in the free-text and structured fields, of the clinical records of over 400 000 service-users. One way to efficiently access and code information on the free-text fields is by using Natural Language Processing (NLP) algorithms, which eliminate the need for researchers to read and code large volumes of text (Perera et al., 2016; Jackson et al., 2017; CRIS NLP Service, 2021). These algorithms analyse text and identify the condition of interest, distinguishing true events from false positives (e.g. notes about a condition without the service-user having that condition) (Perera et al., 2016; Jackson et al., 2017). More information on the NLP algorithms used with CRIS can be found on CRIS NLP Service webpage (CRIS NLP Service, 2021). The study is reported according the RECORD statement (Benchimol et al., 2015).
Participants
SLaM service-users who meet the following inclusion criteria: (i) had a schizophrenia spectrum disorder [WHO ICD-10 codes F20–F29, on structured and free-text fields of the electronic records (CRIS NLP Service, 2021)], diagnosed between 1 January 2007 and 31 December 2020, (ii) were aged between 13 and 65 years at the time of that diagnosis, (iii) had at least one clinical event between 1 January 2007 and 31 December 2020 and (iv) had information regarding ethnic identity.
Variables
Multimorbidity and multimorbidity severity
Based on the current information available on CRIS we were able to identify the prevalence of six LTCs: asthma, bronchitis, diabetes, hypertension, low blood pressure, overweight or obesity and rheumatoid arthritis. Multimorbidity is commonly defined as the coexistence of two or more long-term health conditions [NICE (National Institute for Health and Care Excellence), 2016; Johnston et al., 2019]; so among the cohort of people with a schizophrenia spectrum disorder, multimorbidity was recognised when there was evidence of at least one physical health condition. To assess severity of multimorbidity, we further analysed the odds for the presence of one or two physical health conditions, and the presence of three or more physical health conditions.
The information regarding physical health conditions relied on the use of NLP algorithms (CRIS NLP Service, 2021) and this information was collected during the study's observation period, from 01/01/2007 to 31/12/2020. All algorithms used in this study showed good performance, with precision over 90% and recall over 76% (except for bronchitis, where recall was observed to be 48%) (CRIS NLP Service, 2021). The NLP algorithm identifying asthma analyses mentions of asthma in text. Similarly, bronchitis identification is based on statements of chronic obstructive pulmonary disease, chronic bronchitis, centrilobular emphysema or other terms related to bronchitis. Information on diabetes was derived from a combination of four sources of information: physical health forms, results from blood analysis where the haemoglobin A1c (HbA1c) test (which measures average blood sugar levels) indicated diabetes, and NPL algorithms to identify medications for diabetes or in-text evidence of diabetes. Hypertension was identified via the use of two NLP algorithms: one that focuses on mentions of hypertension problems in the text, and another that analyses information regarding blood pressure; high blood pressure was identified when the systolic pressure was above 140 mmHg, or the diastolic pressure was above 90 mmHg. Low blood pressure was determined when systolic pressure was below 90 mmHg, or the diastolic pressure was below 60 mmHg. To identify overweight or obesity, at any point during the observation period, we used an NLP algorithm that identified Body Mass Index (BMI) values; the information was coded as evidence of overweight or obesity when the BMI was between 25 and 50. Data regarding rheumatoid arthritis was derived from a NLP algorithm identifying mentions of rheumatoid arthritis in text (CRIS NLP Service, 2021).
Exposure and control variables
Ethnicity was derived from 16 NHS categories. White British ethnicity was used as a reference category in the analyses. We used most of the original NHS categories, but due to small samples, we grouped together the mixed ethnicity categories (comprising White and Black African, White Black and Caribbean and White and Asian), and grouped together the other ethnic categories (Other Ethnicity, Gypsy/Irish Traveller group and Arab). Other sociodemographic data comprised gender, age at diagnosis and area-level deprivation. Area-level deprivation was based on the English Indices of Deprivation 2015 (Department for Communities and Local Government, 2015); we retrieved the decile of the index of multiple deprivations attributed to the lower-layer super output area of the service-users address at the diagnosis date. Based on these deciles and considering the high deprivation level in the SLaM catchment area, four groups were derived: most deprived (comprising people living in deciles 1 and 2, corresponding the 20% most deprived areas in England), second-most deprived (comprising people living in decile 3 and 4), middle deprivation (comprising people living in decile 5 and 6), least deprived (comprising deciles 7 to 10, corresponding to the 40% least deprived areas).
To control for the surveillance bias associated with the availability of information, we included a measure that estimated everyone's observation period, commencing with the date of the first diagnosis of SSD after 2007 and finishing at the end of the study's observation period (31/12/2020), or date of death.
Statistical analysis
Logistic regression analyses were conducted to investigate the association between ethnicity and multimorbidity (one or more physical health conditions) while controlling for other sociodemographic information and the observation period's length. Multinomial regression analyses were used to investigate association between ethnicity and morbidity severity, considering no multimorbidity, 1 or 2 physical health conditions and 3 or more physical health conditions. We tested interactions between ethnicity and gender and ethnicity and area-level deprivation in the predictive model for multimorbidity by using the likelihood ratio test comparing the models with and without the interaction terms, with adjustments for age, area-level deprivation and gender, respectively. Statistical analyses were conducted using STATA 15 (StataCorp, 2017).
Results
Participants
The sample comprises 20 800 service-users who met the inclusion criteria; 10% of those meeting the inclusion criteria were excluded because of missing or uncertain ethnicity data. Analyses revealed there were no gender differences between those excluded from the cohort due to missing data on ethnicity and the remaining cohort (47% v. 45% women). The median age at diagnosis for people without ethnicity data was one year earlier (35.9 v. 36.9 years), they were also a little more likely to live in less deprived areas (e.g. proportion living in the least deprived deciles, 7.8% v. 11.8%), and the length of observation period in SLaM was shorter for those with missing data on ethnicity (2.1 v. 8.5 years). The largest ethnic group in the cohort was people of White British ethnicity (35%), followed by Black British or other Black background (15%), Black African (14%), Black Caribbean (9%) and other White ethnicity (9%) (Table 1). The majority of the cohort comprised men (61%), and the median age at diagnosis was 37 years. Most people lived in highly deprived neighbourhoods (38% living in the 20% most deprived areas in England). Further information on the sample description is presented in Table 1.
Table 1.
N (% on the cohort) | No multimorbidity (% on the group) | 1 or more physical health conditions (% on the group) | 1 or 2 physical health conditions (% on the group) | 3 or more physical health conditions (% on the group) | |
---|---|---|---|---|---|
Total | 20 800 (100) | 7215 (34.7) | 13 585 (65.3) | 8459 (40.7) | 5126 (24.6) |
Ethnicity | |||||
White British | 7270 (35.0) | 2767 (38.1) | 4503 (61.9) | 2925 (40.2) | 1578 (21.7) |
Black British/Other Black background | 3141 (15.1) | 851 (27.1) | 2290 (72.9) | 1240 (39.5) | 1050 (33.4) |
Black African | 2853 (13.7) | 838 (29.4) | 2015 (70.6) | 1224 (42.9) | 791 (27.7) |
Black Caribbean | 1825 (8.8) | 423 (23.2) | 1402 (76.8) | 764 (41.9) | 638 (35.0) |
Other White background | 1789 (8.6) | 748 (41.1) | 1065 (58.9) | 766 (42.3) | 299 (16.6) |
Asian British/Other Asian background | 848 (4.1) | 314 (37.0) | 534 (63.0) | 333 (39.3) | 201 (23.7) |
Mixed ethnic background | 689 (3.3) | 244 (35.4) | 445 (64.6) | 274 (39.8) | 171 (24.8) |
Irish | 333 (1.6) | 127 (38.1) | 206 (61.9) | 128 (38.4) | 78 (23.4) |
Indian | 327 (1.6) | 103 (31.5) | 224 (68.5) | 142 (43.4) | 82 (25.1) |
Pakistani | 207 (1.0) | 80 (38.7) | 127 (61.4) | 90 (43.5) | 37 (17.9) |
Chinese | 134 (0.6) | 65 (48.5) | 69 (51.5) | 48 (35.8) | 21 (15.7) |
Bangladeshi | 125 (0.6) | 50 (40.0) | 75 (60.0) | 51 (40.1) | 24 (19.2) |
Other ethnic background | 1259 (6.1) | 605 (49.1) | 630 (50.9) | 474 (38.4) | 156 (12.6) |
Gender | |||||
Men | 12 593 (60.5) | 4352 (34.6) | 8241 (65.4) | 5023 (39.9) | 3218 (25.6) |
Women | 8207 (39.5) | 2863 (34.9) | 5344 (65.1) | 3436 (41.9) | 1908 (23.3) |
Age: Mdn (IQR) | 36.9 (27.0–47.1) | 35.6 (26.9–45.7) | 37.6 (27.0–47.8) | 37.8 (27.3–48.1) | 37.1 (27.3–48.1) |
13–17 years | 1018 (4.9) | 399 (39.2) | 619 (60.8) | 412 (40.47) | 207 (20.3) |
18–34 years | 8367 (40.2) | 3076 (36.8) | 5291 (63.2) | 3232 (38.6) | 2059 (24.6) |
35–49 years | 7404 (35.6) | 2256 (34.1) | 4878 (65.9) | 3018 (40.8) | 1860 (25.1) |
50–65 years | 4011 (19.3) | 1214 (30.27) | 27 978 (69.7) | 1797 (44.8) | 1000 (24.9) |
Area-level deprivation a (7.4% missing data) | |||||
Least deprived (IMD deciles 7–10) | 1497 (7.8) | 634 (42.4) | 863 (57.7) | 606 (40.5) | 257 (17.2) |
Middle deprivation (IMD deciles 5–6) | 3141 (16.3) | 1093 (34.8) | 2048 (65.2) | 1288 (41.0) | 760 (24.2) |
Second most deprived (IMD deciles 3–4) | 7300 (37.9) | 2470 (33.8) | 4830 (66.2) | 2939 (40.3) | 1891 (25.9) |
Most deprived (IMD deciles 1–2) | 7328 (38.0) | 2391 (32.6) | 4937 (67.4) | 3019 (41.2) | 1918 (26.2) |
Observation period (years): M (SD) | 8.11 (4.40) | 7.31 (4.35) | 8.55 (4.37) | 7.83 (4.43) | 9.74 (4.00) |
Physical health conditions | % on multimorbidity group | ||||
Asthma | 3119 (15.0) | 0 | 3119 (23) | 1126 (13.3) | 1993 (38.9) |
Bronchitis | 552 (2.7) | 0 | 552 (4.1) | 115 (1.4) | 437 (8.5) |
Diabetes | 6687 (32.2) | 0 | 6687 (49.2) | 2751 (32.5) | 3936 (76.8) |
Hypertension/high blood pressure | 9481 (45.6) | 0 | 9481 (59.8) | 4712 (55.7) | 4769 (93.0) |
Low blood pressure | 5112 (24.6) | 0 | 5112 (37.6) | 1616 (19.1) | 3496 (68.2) |
Overweight or obesity | 5438 (26.1) | 0 | 5438 (40.0) | 1817 (21.5) | 3621 (70.6) |
Rheumatoid arthritis | 172 (0.8) | 0 | 172 (1.3) | 57 (0.7) | 115 (2.2) |
Notes: aProportions for area-level deprivation were calculated from available data.
The most prevalent conditions were hypertension (46%), followed by diabetes (32%), overweight or obesity (26%), low blood pressure (25%) and asthma (15%); bronchitis (3%) and rheumatoid arthritis (1%) were not common (Table 1). Information on the sociodemographic and clinical factors stratified by ethnicity are presented in Table 2.
Table 2.
% within ethnicity | White British | Black British | Black African | Black Caribbean | Other White | Asian British | Mixed ethnicity | Irish | Indian | Pakistani | Chinese | Bangladeshi | Other ethnicity | p-value |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Women (Gender) | 38.1 | 38.7 | 42.7 | 40.5 | 38.6 | 39.4 | 43.8 | 29.1 | 39.5 | 43.5 | 60.5 | 40.8 | 38.9 | <0.001 |
Age: Mdn (IQR) | 39.4 (28.6–50.5) | 32.7 (24.0–42.9) | 34.9 (26.3–43.9) | 42.8 (31.9–50.5) | 35.3 (28.1–44.3) | 36.1 (26.7–45.3) | 29.8 (22.0–40.6) | 43.0 (32.5–52.9) | 41.3 (32.1–51.3) | 32.6 (24.9–43.1) | 32.1 (26.3–41.7) | 31.0 (25.3–39.2) | 34.9 (27.0–45.5) | |
13–17 years | 5.0 | 6.7 | 3.8 | 3.3 | 2.6 | 5.1 | 12.8 | 3.9 | 3.4 | 7.25 | 4.5 | 4.8 | 3.4 | <0.001 |
18–34 years | 34.0 | 48.4 | 46.5 | 27.0 | 46.5 | 42.1 | 48.6 | 28.5 | 29.7 | 48.8 | 55.2 | 60.0 | 46.7 | |
35–49 years | 34.7 | 35.6 | 37.1 | 43.0 | 35.1 | 35.7 | 28.6 | 37.5 | 37.9 | 28.0 | 28.4 | 28.8 | 33.0 | |
50–65 years | 26.3 | 9.3 | 12.7 | 26.7 | 15.8 | 17.1 | 10.0 | 30.0 | 29.1 | 15.9 | 11.9 | 6.4 | 16.8 | |
Area-level deprivation | <0.001 | |||||||||||||
Least deprived (7–10 deciles) | 12.9 | 3.8 | 2.6 | 3.6 | 8.7 | 8.2 | 8.8 | 6.5 | 6.4 | 4.6 | 9.2 | 7.8 | 5.3 | |
Middle deprivation (5–6 deciles) | 18.7 | 15.0 | 11.0 | 15.5 | 17.9 | 14.8 | 15.5 | 15.7 | 22.0 | 25.8 | 17.7 | 14.8 | 15.2 | |
Second most deprived (3–4 deciles) | 34.7 | 40.7 | 38.8 | 38.8 | 36.9 | 41.3 | 40.3 | 40.82 | 45.5 | 43.9 | 34.5 | 30.4 | 40.7 | |
Most deprived (1–2 deciles) | 33.7 | 40.5 | 47.6 | 42.1 | 36.5 | 35.7 | 35.4 | 37.1 | 26.1 | 25.8 | 38.7 | 47.0 | 38.8 | |
Observation period (years): M (SD) | 7.78 (4.42) | 8.44 (4.44) | 8.56 (4.33) | 9.70 (4.29) | 7.51 (4.32) | 8.26 (4.28) | 7.82 (4.59) | 8.37 (4.28) | 8.46 (4.40) | 7.32 (4.49) | 8.70 (4.04) | 8.04 (4.12) | 6.84 (3.82) | <0.001 |
Physical health comorbidities | ||||||||||||||
Asthma | 16.2 | 19.9 | 11.2 | 17.9 | 10.3 | 12.0 | 18.6 | 17.4 | 15.3 | 12.6 | 6.7 | 10.4 | 8.1 | <0.001 |
Bronchitis | 4.0 | 2.0 | 1.5 | 5.9 | 2.0 | 2.0 | 2.0 | 4.2 | 1.8 | 2.4 | 1.5 | 0.8 | 0.6 | <0.001 |
Diabetes | 27.7 | 38.9 | 35.9 | 46.5 | 23.8 | 35.9 | 33.0 | 28.5 | 39.8 | 30.4 | 22.4 | 34.4 | 20.4 | <0.001 |
Hypertension | 41.8 | 53.7 | 53.0 | 60.3 | 36.5 | 40.9 | 44.0 | 41.4 | 49.2 | 35.3 | 35.1 | 34.4 | 30.3 | <0.001 |
Low blood pressure | 22.2 | 31.5 | 26.9 | 28.7 | 21.4 | 25.0 | 25.5 | 22.8 | 20.5 | 21.7 | 24.6 | 17.6 | 16.5 | <0.001 |
Overweight or obesity | 22.2 | 33.6 | 30.9 | 32.6 | 22.1 | 25.4 | 25.1 | 23.1 | 22.0 | 24.6 | 20.9 | 28.8 | 19.6 | <0.001 |
Rheumatoid arthritis | 1.1 | 0.7 | 0.6 | 1.2 | 0.6 | 0.5 | 1.0 | 0.9 | 0.6 | 1.0 | 0.0 | 00.0 | 0.6 | 0.165 |
Ethnicity and odds for multimorbidity
The results from the logistic regression analyses (Table 3) showed that adjusting for age, gender, area-level deprivation and observation period, compared to White British people, Black African [aOR = 1.41, 95% CI (1.23–1.56)], Black Caribbean [aOR = 1.79, 95% CI (1.58–2.03)] and Black British people [aOR = 1.64, 95% CI (1.49–1.81)] were more likely to have multimorbidity (psychosis plus one physical health condition). Reduced odds for multimorbidity were observed among people of Chinese [aOR = 0.61, 95% CI (0.43–0.88)] and Other ethnicities [aOR = 0.66, 95% CI (0.58–0.75)]. The magnitude of these differences was even higher when comparing the odds for severe multimorbidity, having 3 or more physical health conditions (Table 3). No significant differences in odds for multimorbidity were observed between White British and people of South Asian background or Asian British, Irish, other White background and mixed race. However, in the model regarding multimorbidity severity, people of White Other ethnicity were observed to have reduced odds for 3 or more physical health conditions [aOR = 0.78, 95% CI (0.66–0.92)], compared to White British people. The effects of ethnicity on multimorbidity did not differ by gender or level of deprivation as indicated by the statistically non-significant interaction terms in the logistic models [likelihood ratio (LR) test based chi-squared = 14.45(12), p = 0.273 for ethnicity × gender and 44.48(36), p = 0.148 for ethnicity × deprivation interactions respectively].
Table 3.
1 or more physical health conditions | 1 or 2 physical health conditions | 3 or more physical health conditions | ||
---|---|---|---|---|
Crude OR [95% CI]a | Adjusted OR [95% CI]a | Adjusted OR [95% CI]b | Adjusted OR [95% CI]b | |
Ethnicity | ||||
White British | Ref | Ref | Ref | Ref |
Black British/Other Black background | 1.65 [1.51–1.81] | 1.64 [1.49–1.81] | 1.42 [1.27–1.58] | 2.06 [1.83–2.31] |
Black African | 1.48 [1.35–1.62] | 1.41 [1.23–1.56] | 1.36 [1.22–1.52] | 1.50 [1.33–1.70] |
Black Caribbean | 2.04 [1.81–2.29] | 1.79 [1.58–2.03] | 1.61 [1.40–1.84] | 2.09 [1.81–2.42] |
Other White background | 0.88 [0.79–0.98] | 0.95 [0.84–1.07] | 1.04 [0.91–1.18] | 0.78 [0.66–0.92] |
Asian British/Other Asian background | 1.05 [0.90–1.21] | 1.05 [0.90–1.23] | 1.05 [0.88–1.24] | 1.06 [0.87–1.30] |
Irish | 1.00 [0.79–1.25] | 0.94 [0.74–1.21] | 0.90 [0.69–1.19] | 1.02 [0.75–1.39] |
Indian | 1.34 [1.05–1.70] | 1.25 [0.97–1.60] | 1.25 [0.96–1.63] | 1.26 [0.92–1.71] |
Pakistani | 0.98 [0.73–1.30] | 1.03 [0.76–1.38] | 1.09 [0.80–1.50] | 0.89 [0.59–1.33] |
Chinese | 0.65 [0.46–0.92] | 0.61 [0.43–0.88] | 0.70 [0.47–1.04] | 0.47 [0.27–0.81] |
Bangladeshi | 0.92 [0.64–1.32] | 0.96 [0.66–1.42] | 1.07 [0.71–1.61] | 0.78 [0.46–1.33] |
Mixed ethnic background | 1.12 [0.95–1.32] | 1.15 [0.97–1.36] | 1.11 [0.92–1.34] | 1.22 [0.98–1.52] |
Other ethnic background | 0.64 [0.57–0.72] | 0.66 [0.58–0.75] | 0.75 [0.65–0.86] | 0.50 [0.41–0.61] |
Gender | ||||
Men | Ref | Ref | Ref | Ref |
Women | 0.99 [0.92–1.04] | 0.97 [0.92–1.04] | 1.02 [0.95–1.09] | 0.90 [0.83–0.98] |
Age | ||||
13–17 years | Ref | Ref | Ref | Ref |
18–34 years | 1.11 [0.97–1.27] | 1.05 [0.91–1.21] | 0.99 [0.86–1.16] | 1.15 [0.96–1.39] |
35–49 years | 1.24 [1.09–1.42] | 1.13 [0.99–1.31] | 1.12 [0.97–1.31] | 1.14 [0.95–1.38] |
50–65 years | 1.49 [1.29–1.71] | 1.53 [1.32–1.78] | 1.49 [1.27–1.75] | 1.60 [1.31–1.96] |
Area-level deprivation | ||||
Least deprived (IMD deciles 7–10) | Ref | Ref | Ref | Ref |
Middle deprivation (IMD deciles 5–6) | 1.38 [1.21–1.56] | 1.26 [1.11–1.43] | 1.17 [1.02–1.34] | 1.50 [1.25–1.79] |
Second most deprived (IMD deciles 3–4) | 1.44 [1.28–1.61] | 1.27 [1.13–1.43] | 1.15 [1.02–1.31] | 1.56 [1.32–1.84] |
Most deprived (IMD deciles 1–2) | 1.52 [1.35–1.70] | 1.32 [1.18–1.49] | 1.21 [1.07–1.37] | 1.61 [1.37–1.90] |
Observation period (years) | 1.07 [1.06–1.07] | 1.06 [1.05–1.07] | 1.02 [1.02–1.03] | 1.13 [1.12–1.14] |
Notes: a – results from logistic regression; b – results from multinomial regression. Significant results are indicated in bold.
Discussion
We investigated ethnic inequities in risks of multimorbidity in people with psychosis, using data from the electronic health records of South London and Maudsley NHS Trust. Black African, Black Caribbean and Black British people with psychosis have around 1.5 greater odds for multimorbidity, and around twice the odds for severe multimorbidity (i.e. psychosis plus three physical health conditions). People of Chinese ethnicity and Other ethnicity had reduced odds for multimorbidity. This is the first study that investigates potential ethnic inequities in multimorbidity among a cohort of people with psychosis. These findings are partly in line with a study that observed a greater risk of the development of diabetes among minoritised ethnic people within the first year of treatment for psychosis (Gaughran et al., 2019). Also, the pattern of observed inequities is partially similar to a study of multimorbidity among a national sample of older adults (Watkinson et al., 2021). Similar findings are the greater risk observed among Black people, the reduced odds among Chinese people and the absence of differences among people with Mixed ethnicity (Watkinson et al., 2021). However, in our study, we did not observe increased odds for multimorbidity among people of South Asian, Asian British or other ethnicities. The age difference of the samples and the fact that we only investigated six health conditions, while the study of multimorbidity among older adults investigated 14 (Watkinson et al., 2021), may be the reasons for differences in findings.
Multiple studies have investigated the reasons for ethnic inequities in health. Except for a few conditions (e.g. sickle cell anaemia) that have a simple genetic basis, studies have failed to provide sound biological explanations for the ethnic inequities observed (Dressler et al., 2005; Adler and Rehkopf, 2008). Geographical variance in the prevalence of health conditions, as well as the significant associations between area deprivation, income, education and occupation with multimorbidity, suggest that differences in health and multimorbidity are more likely rooted in social conditions than are due to innate biological vulnerabilities (Nazroo, 1998; Evandrou et al., 2016; Stubbs et al., 2016; Larsen et al., 2017; Verest et al., 2019; Dugravot et al., 2020; Dubath et al., 2021). Studies show that exposure to stress is associated with the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and related cortisol awakening response (CAR), with implications for metabolic and inflammatory processes, further dysregulation of the immune response and multi-illness onset (O'Connor et al., 2021). Furthermore, social epigenetics studies report evidence of change in DNA methylation leading to epigenetic ageing amongst people who faced childhood adversity, low socioeconomic status in childhood and adulthood, perceived discrimination and neighbourhood disadvantage (Martin et al., 2022).
The observed ethnic inequities could probably be driven by inequities in the social determinants of health beyond the included measure of area deprivation, including social marginalisation, racial discrimination, and, for migrants, the stresses related to migration and acculturation (Hatch and Dohrenwend, 2007; Allen et al., 2014; Cabinet Office, 2018; Jongsma et al., 2021b; Marmot et al., 2020; Nazroo et al., 2020; Bhui et al., 2021). For instance, experiences of racism and racial discrimination have been related to worse mental and physical health, including the onset of psychosis, diabetes, respiratory illness and hypertension (Karlsen and Nazroo, 2002; Karlsen et al., 2005; Paradies et al., 2015; Pearce et al., 2019; Williams et al., 2019; Jongsma et al., 2021a). Health-related behaviours could mediate the relationships between social adversity and the onset of multimorbidity (Goosby et al., 2017; Williams et al., 2019; Bhui et al., 2021). The findings may also reflect the shared aetiology of mental and physical health conditions. One study has reported an association between the number of psychotic symptoms and number of physical health conditions (Moreno et al., 2013). The role of social stress, allostatic load, bodily inflammation and coagulation have been related to the onset of disorders in physical health, as well as psychosis; these mechanisms may explain multimorbidity with psychosis (Beckie, 2012; Goosby et al., 2017; Howes and McCutcheon, 2017; Lund et al., 2018; Heurich et al., 2022).
This study has implications for integrated care and shows the need for developing targeted interventions to reduced ethnic inequities. Literature suggests there is room for improving the health care provided. Ethnic minority people may not be disadvantaged in terms of contacts with the medical health system; a national representative study shows that after adjusting for self-assessed level of health and number of long-term conditions, people of Caribbean, Indian, Pakistani and Bangladeshi backgrounds were more likely to have had an appointment in the two weeks prior the survey (Nazroo et al., 2009). However, there is evidence that Asian older adults are more dissatisfied with the care provided by GPs, as compared to White British, and older adults of most ethnic groups report insufficient support from local services to manage their health conditions and have low confidence in that management (Watkinson et al., 2021).
There are specific barriers to managing physical health among people with psychosis, which range from increased individual risk factors for poorer health (e.g. higher rates of substance use, smoking, lack of exercise and poorer diet), to service-related factors (e.g. lack of clarity in who is responsible for managing health problems among people with psychosis) (De Hert et al., 2011; Moore et al., 2015; Bellass et al., 2021). These barriers can be aggravated for ethnic minority people due to discrimination, difficulties in communication or other cultural barriers. There is evidence that Black people with an SMI are less likely than White counterparts to have psychiatric diagnostic information recorded in hospital records after an emergency hospital admission (Mansour et al., 2020). This under-identification potentially is related to reduced opportunities for enhanced continuity of care. The emphasise on increasing comprehensive personalised care may be a useful resource to reduce the ethnic inequities in multimorbidity (as it aims to improve individual levels of self-management of chronic health conditions, as well as to promote opportunities for people to have more community support), and evidence suggests that this leads to improved health outcomes (Coulter et al., 2015). However, information on how people with psychosis manage their physical health and any specific initiatives to reduce ethnic inequities in multimorbidity amongst people with psychosis is lacking (Das-Munshi et al., 2016). This study identifies the need to promote integrated care for SMI and multimorbidity (De Hert et al., 2011; Moore et al., 2015; Bellass et al., 2021).
Strengths and limitations
This study used data from one of the UK's largest secondary mental health facilities, serving an ethnically diverse community. The cohort of the study is representative of South London and Maudsley NHS Trust catchment, and the findings should be generalisable to other ethnically dense urban areas in the United Kingdom. Indeed, most ethnic minorities live in urban areas. Ethnicity was self-defined, within NHS categories; however we could not include other relevant factors that can be related to inequities in health, most importantly migration, which could be associated with potential related barriers in the use of health services and under-detection of health conditions, but also an investigation of the healthy migrant paradox (Helgesson et al., 2019; Oh et al., 2021b). Also, we could not adjust for individual measures socioeconomic status (e.g. income, level of education), experiences of racism and discrimination or other factors of social adversity which have been associated with health inequities (Karlsen and Nazroo, 2002; Beckie, 2012; Goosby et al., 2017). There are limitations in using Natural Language Processing (NLP) algorithms to assess the prevalence of physical health conditions, however the use of NLP enabled us to investigate ethnic inequities in a larger sample of people than what would be possible if restricting to people whose data could be linked to other administrative datasets that contain data on physical health, such as the Lambeth DataNet (Woodhead et al., 2014). There is the risk of underestimation of the prevalence of some physical health conditions, as they would be managed in primary care and not recorded in SLaM (Gaughran et al., 2019). We did not account for potential ethnic differences in psychotic illness severity and healthcare service use (Chui et al., 2021; Morris et al., 2020), which may affect the availability of information. Moreover, only the conditions relevant to the aetiology and management of psychosis may be reported in SLaM electronic records, so we may have less information on other conditions. We did not adjust for the type of pharmacological treatment for psychosis, which could be related to the presence of the included physical conditions (Baxter et al., 2016; Dubath et al., 2021). Finally, we could not investigate the timing of the onset of the different health conditions. Future cohort studies are needed to verify and expand on our findings (e.g. Das-Munshi et al., 2016).
Conclusions
This study shows that Black people with psychosis are at higher risk of multimorbidity. Although this study is not focused on aetiology, the findings are consistent with adversity-related onset of disease, where marginalised ethnic groups face higher rates of psychosis and other health conditions when living with this severe mental illness (Dubath et al., 2021; Jongsma et al., 2021a; Watkinson et al., 2021). The observed ethnic inequities in health show the need for integrated care and multi-disease prevention among minoritised ethnic groups.
Author contributions
K. B. developed the original idea in relation to new work on syndemics, and developed this with D. F. d. F. K. B., D. F. d. F., M. K., J. N. and R. D. H. were involved in the reviewing the methodology and analytic plans. M. P. and H. S. curated the data. D. F. d. F. undertook all data analyses and wrote the first draft. All authors provided critical insight, reviewed and suggested edits and agreed to the final version.
Financial support
This work utilised the Clinical Record Interactive Search (CRIS) platform, funded and developed by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London. Additionally, this work was supported by the Lankelly Chase Foundation, which funded the work of the Synergi Collaborative Centre (a 5-year national initiative to build a knowledge hub on ethnic inequities and multiple disadvantages in severe mental illness in the UK). The funders of the study had no role in study design, data collection, data analysis, data interpretation, writing of the manuscript or in the decision to submit it for publication.
Conflict of interest
D. F. d. F. has received research funding from Janssen and H Lundbeck for work outside this study. R. D. H. has received research funding from Roche, Pfizer, Janssen and H Lundbeck for work outside this study.
Ethical standards
CRIS dataset received approval from the Oxford C Research Ethics Committee (18/SC/0372). All projects using the CRIS dataset are submitted for approval to an oversight committee led by service-users (this project reference: 20-075). Service-users consent for publication of studies using CRIS data is not required.
Footnotes
We use the term inequity in line with the World Health Organisation definition of health equity as ‘the absence of unfair, avoidable or remediable differences among groups of people, whether those groups are defined socially, economically, demographically, or geographically or by other dimensions of inequality (e.g. sex, gender, ethnicity, disability, or sexual orientation).’ (World Health Organization, 2021).
Data
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to the Information Governance framework and Research Ethics Committee approval in place concerning CRIS data use.
References
- Adler NE and Rehkopf DH (2008) Disparities in health: descriptions, causes, and mechanisms. Annual Review of Public Health 29, 235–252. [DOI] [PubMed] [Google Scholar]
- Allen J, Balfour R, Bell R and Marmot M (2014) Social determinants of mental health. International Review of Psychiatry 26, 392–407. [DOI] [PubMed] [Google Scholar]
- Ashworth M, Durbaba S, Whitney D, Crompton J, Wright M and Dodhia H (2019) Journey to multimorbidity: longitudinal analysis exploring cardiovascular risk factors and sociodemographic determinants in an urban setting. BMJ Open 9, e031649. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baxter AJ, Harris MG, Khatib Y, Brugha TS, Bien H and Bhui K (2016) Reducing excess mortality due to chronic disease in people with severe mental illness: meta-review of health interventions. British Journal of Psychiatry 208, 322–329. [DOI] [PubMed] [Google Scholar]
- Beckie TM (2012) A systematic review of allostatic load, health, and health disparities. Biological Research for Nursing 14, 311–346. [DOI] [PubMed] [Google Scholar]
- Bellass S, Lister J, Kitchen CEW, Kramer L, Alderson SL, Doran T, Gilbody S, Han L, Hewitt C, Holt RIG, Jacobs R, Prady SL, Shiers D, Siddiqi N and Taylor J (2021) Living with diabetes alongside a severe mental illness: a qualitative exploration with people with severe mental illness, family members and healthcare staff. Diabetic Medicine 38, 1–28. [DOI] [PubMed] [Google Scholar]
- Benchimol EI, Smeeth L, Guttmann A, Harron K, Moher D, Petersen I, Sørensen HT, von Elm E and Langan SM (2015) The reporting of studies conducted using observational routinely-collected health data (RECORD) statement. PLOS Medicine 12, e1001885. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bhui PK, Havorsrud K, Mooney R and Hosang GM (2021) Is psychosis a syndemic manifestation of historical and contemporary adversity? Findings from UKBioBank. The British Journal of Psychiatry 219, 686–694. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bisquera A, Turner EB, Ledwaba-Chapman L, Dunbar-Rees R, Hafezparast N, Gulliford M, Durbaba S, Soley-Bori M, Fox-Rushby J, Dodhia H, Ashworth M and Wang Y (2021) Inequalities in developing multimorbidity over time: a population-based cohort study from an urban, multi-ethnic borough in the United Kingdom. The Lancet Regional Health – Europe 12, 100247. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cabinet Office (2018) Race Disparity Audit. Available at https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/686071/Revised_RDA_report_March_2018.pdf.
- Chui Z, Gazard B, MacCrimmon S, Harwood H, Downs J, Bakolis I, Polling C, Rhead R and Hatch SL (2021) Inequalities in referral pathways for young people accessing secondary mental health services in south-east London. European Child & Adolescent Psychiatry 30, 1113–1128. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Coulter A, Entwistle VA, Eccles A, Ryan S, Shepperd S and Perera R (2015) Personalised care planning for adults with chronic or long-term health conditions. Cochrane Database of Systematic Reviews. 10.1002/14651858.CD010523.pub2 [DOI] [PMC free article] [PubMed] [Google Scholar]
- CRIS NLP Service (2021) Library of production-ready applications, v1.6. Available at https://www.maudsleybrc.nihr.ac.uk/facilities/clinical-record-interactive-search-cris/cris-natural-language-processing/.
- Das-Munshi J, Ashworth M, Gaughran F, Hull S, Morgan C, Nazroo J, Roberts A, Rose D, Schofield P, Stewart R, Thornicroft G and Prince MJ (2016) Ethnicity and cardiovascular health inequalities in people with severe mental illnesses: protocol for the E-CHASM study. Social Psychiatry and Psychiatric Epidemiology 51, 627–638. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Das-Munshi J, Chang C-K, Dutta R, Morgan C, Nazroo J, Stewart R and Prince MJ (2017) Ethnicity and excess mortality in severe mental illness: a cohort study. The Lancet Psychiatry 4, 389–399. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Das-Munshi J, Chang CK, Dregan A, Hatch S, Morgan C, Thornicroft G, Stewart R and Hotopf M (2021) How do ethnicity and deprivation impact on life expectancy at birth in people with serious mental illness? Observational study in the UK. Psychological Medicine 51, 2581–2589. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Hert M, Cohen D, Bobes J, Cetkovich-Bakmas M, Leucht S, Ndetei DM, Newcomer JW, Uwakwe R, Asai I, Möller H.-J, Gautam S, Detraux J and Correll CU (2011) Physical illness in patients with severe mental disorders. II. Barriers to care, monitoring and treatment guidelines, plus recommendations at the system and individual level. World Psychiatry 10, 138–151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Department for Communities and Local Government (2015) The English Indices of Deprivation 2015 – Technical Report. Available at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/464485/English_Indices_of_Deprivation_2015_-_Technical-Report.pdf.
- Dressler WW, Oths KS and Gravlee CC (2005) Race and ethnicity in public health research: models to explain health disparities. Annual Review of Anthropology 34, 231–252. [Google Scholar]
- Dubath C, Gholam-Rezaee M, Sjaarda J, Levier A, Saigi-Morgui N, Delacrétaz A, Glatard A, Panczak R, Correll CU, Solida A, Plessen KJ, von Gunten A, Kutalik Z, Conus P and Eap CB (2021) Socio-economic position as a moderator of cardiometabolic outcomes in patients receiving psychotropic treatment associated with weight gain: results from a prospective 12-month inception cohort study and a large population-based cohort. Translational Psychiatry 11, 360. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dugravot A, Fayosse A, Dumurgier J, Bouillon K, Rayana TB, Schnitzler A, Kivimaki M, Sabia S and Singh-Manoux A (2020) Social inequalities in multimorbidity, frailty, disability, and transitions to mortality: a 24-year follow-up of the Whitehall II cohort study. The Lancet Public Health 5, e42–e50. [DOI] [PMC free article] [PubMed] [Google Scholar]
- El-Sayed AM, Scarborough P and Galea S (2011) Ethnic inequalities in obesity among children and adults in the UK: a systematic review of the literature. Obesity Reviews 12, e516–e534. [DOI] [PubMed] [Google Scholar]
- Evandrou M, Falkingham J, Feng Z and Vlachantoni A (2016) Ethnic inequalities in limiting health and self-reported health in later life revisited. Journal of Epidemiology and Community Health 70, 653–662. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Freitas DF, Fernandes-Jesus M, Ferreira PD, Coimbra S, Teixeira P, Moura A, Gato J, Marques S and Fontaine AM (2018) Psychological correlates of perceived ethnic discrimination in Europe: a meta-analysis. Psychology of Violence 8, 712–725. [Google Scholar]
- Gaughran F, Stahl D, Stringer D, Hopkins D, Atakan Z, Greenwood K, Patel A, Smith S, Gardner-Sood P, Lally J, Heslin M, Stubbs B, Bonaccorso S, Kolliakou A, Howes O, Taylor D, Di Forti M, David AS, Murray RM and Ismail K (2019) Effect of lifestyle, medication and ethnicity on cardiometabolic risk in the year following the first episode of psychosis: prospective cohort study. British Journal of Psychiatry 215, 712–719. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goosby BJ, Straley E and Cheadle JE (2017) Discrimination, sleep, and stress reactivity: pathways to African American-White cardiometabolic risk inequities. Population Research and Policy Review 36, 699–716. [Google Scholar]
- Halonen JI, Vahtera J, Kivimäki M, Pentti J, Kawachi I and Subramanian SV (2014) Adverse experiences in childhood, adulthood neighbourhood disadvantage and health behaviours. Journal of Epidemiology and Community Health 68, 741–746. [DOI] [PubMed] [Google Scholar]
- Harris R, Tobias M, Jeffreys M, Waldegrave K, Karlsen S and Nazroo J (2006) Effects of self-reported racial discrimination and deprivation on Māori health and inequalities in New Zealand: cross-sectional study. Lancet 367, 2005–2009. [DOI] [PubMed] [Google Scholar]
- Hatch SL and Dohrenwend BP (2007) Distribution of traumatic and other stressful life events by race/ethnicity, gender, SES and age: a review of the research. American Journal of Community Psychology 40, 313–332. [DOI] [PubMed] [Google Scholar]
- Head A, Fleming K, Kypridemos C, Schofield P, Pearson-Stuttard J and O'Flaherty M (2021) Inequalities in incident and prevalent multimorbidity in England, 2004–19: a population-based, descriptive study. The Lancet Healthy Longevity 2, e489–e497. [DOI] [PubMed] [Google Scholar]
- Helgesson M, Johansson B, Nordquist T, Vingård E and Svartengren M (2019) Healthy migrant effect in the Swedish context: a register-based, longitudinal cohort study. BMJ Open 9, e026972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Heurich M, Föcking M, Mongan D, Cagney G and Cotter DR (2022) Dysregulation of complement and coagulation pathways: emerging mechanisms in the development of psychosis. Molecular Psychiatry 27, 127–140.. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Howes OD and McCutcheon R (2017) Inflammation and the neural diathesis-stress hypothesis of schizophrenia: a reconceptualization. Translational Psychiatry 7, e1024. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jackson RG, Patel R, Jayatilleke N, Kolliakou A, Ball M, Gorrell G, Roberts A, Dobson RJ and Stewart R (2017) Natural language processing to extract symptoms of severe mental illness from clinical text: the clinical record interactive search comprehensive data extraction (CRIS-CODE) project. BMJ Open 7, e012012. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnston MC, Crilly M, Black C, Prescott GJ and Mercer SW (2019) Defining and measuring multimorbidity: a systematic review of systematic reviews. European Journal of Public Health 29, 182–189. [DOI] [PubMed] [Google Scholar]
- Jongsma HE, Gayer-Anderson C, Tarricone I, Velthorst E, van der Ven E, Quattrone D, di Forti M, Menezes PR, Del-Ben CM, Arango C, Lasalvia A, Berardi D, La Cascia C, Bobes J, Bernardo M, Sanjuán J, Santos JL, Arrojo M, de Haan L, Tortelli A, Szöke A, Murray RM, Rutten BP, van Os J, Morgan C, Jones PB and Kirkbride JB (2021a) Social disadvantage, linguistic distance, ethnic minority status and first-episode psychosis: results from the EU-GEI case–control study. Psychological Medicine 51, 1–13. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jongsma HE, Karlsen S, Kirkbride JB and Jones PB (2021b) Understanding the excess psychosis risk in ethnic minorities: the impact of structure and identity. Social Psychiatry and Psychiatric Epidemiology 56, 1913–1921. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karlsen S and Nazroo JY (2002) Relation between racial discrimination, social class, and health among ethnic minority groups. American Journal of Public Health 92, 624–631. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karlsen S, Nazroo JY, McKenzie K, Bhui K and Weich S (2005) Racism, psychosis and common mental disorder among ethnic minority groups in England. Psychological Medicine 35, 1795–1803. [DOI] [PubMed] [Google Scholar]
- Kuan V, Denaxas S, Gonzalez-Izquierdo A, Direk K, Bhatti O, Husain S, Sutaria S, Hingorani M, Nitsch D, Parisinos CA, Lumbers RT, Mathur R, Sofat R, Casas JP, Wong IC, Hemingway H and Hingorani AD (2019) A chronological map of 308 physical and mental health conditions from 4 million individuals in the English National Health Service. The Lancet Digital Health 1, e63–e77. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kugathasan P, Wu H, Gaughran F, Nielsen RE, Pritchard M, Dobson R, Stewart R and Stubbs B (2020) Association of physical health multimorbidity with mortality in people with schizophrenia spectrum disorders: using a novel semantic search system that captures physical diseases in electronic patient records. Schizophrenia Research 216, 408–415. [DOI] [PubMed] [Google Scholar]
- Larsen FB, Pedersen MH, Friis K, Glümer C and Lasgaard M (2017) A latent class analysis of multimorbidity and the relationship to socio-demographic factors and health-related quality of life. A national population-based study of 162,283 Danish adults. PLoS One 12, e0169426. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lin L, Wang HH, Lu C, Chen W and Guo VY (2021) Adverse childhood experiences and subsequent chronic diseases among middle-aged or older adults in China and associations with demographic and socioeconomic characteristics. JAMA Network Open 4, e2130143. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lund C, Brooke-Sumner C, Baingana F, Baron EC, Breuer E, Chandra P, Haushofer J, Herrman H, Jordans M, Kieling C, Medina-Mora ME, Morgan E, Omigbodun O, Tol W, Patel V and Saxena S (2018) Social determinants of mental disorders and the sustainable development goals: a systematic review of reviews. The Lancet Psychiatry 5, 357–369. [DOI] [PubMed] [Google Scholar]
- Mansour H, Mueller C, Davis KAS, Burton A, Shetty H, Hotopf M, Osborn D, Stewart R and Sommerlad A (2020) Severe mental illness diagnosis in English general hospitals 2006-2017: a registry linkage study. PLOS Medicine 17, e1003306. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marmot M, Allen J, Boyce T, Goldblatt P and Morrison J (2020) Health Equity in England: The Marmot Review 10 Years On. London: Institute of Health Equity. Available at http://www.instituteofhealthequity.org/resources-reports/marmot-review-10-years-on. [Google Scholar]
- Martin CL, Ghastine L, Lodge EK, Dhingra R and Ward-Caviness C (2022) Understanding health inequalities through the lens of social epigenetics. Annual Review of Public Health 43, 235–254. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mathur R, Hull SA, Badrick E and Robson J (2011) Cardiovascular multimorbidity: the effect of ethnicity on prevalence and risk factor management. British Journal of General Practice 61, e262–e270. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McEwen BS (1998) Stress, adaptation, and disease: allostasis and allostatic load. Annals of the New York Academy of Sciences 840, 33–44. [DOI] [PubMed] [Google Scholar]
- Moore S, Shiers D, Daly B, Mitchell AJ and Gaughran F (2015) Promoting physical health for people with schizophrenia by reducing disparities in medical and dental care. Acta Psychiatrica Scandinavica 132, 109–121. [DOI] [PubMed] [Google Scholar]
- Moreno C, Nuevo R, Chatterji S, Verdes E, Arango C and Ayuso-Mateos JL (2013) Psychotic symptoms are associated with physical health problems independently of a mental disorder diagnosis: results from the WHO world health survey. World Psychiatry 12, 251–257. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morgan C, Knowles G and Hutchinson G (2019) Migration, ethnicity and psychoses: evidence, models and future directions. World Psychiatry 18, 247–258. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morris RM, Sellwood W, Edge D, Colling C, Stewart R, Cupitt C and Das-Munshi J (2020) Ethnicity and impact on the receipt of cognitive–behavioural therapy in people with psychosis or bipolar disorder: an English cohort study. BMJ Open 10, e034913. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nazroo JY (1998) Genetic, cultural or socio-economic vulnerability? Explaining ethnic inequalities in health. Sociology of Health & Illness 20, 710–730. [Google Scholar]
- Nazroo JY and Williams DR (2006) The social determination of ethnic/racial inequalities in health. In Marmot M and Wilkinson RG (eds), Social Determinants of Health. Oxford: Oxford University Press, pp. 238–266. Available at doi: 10.1093/acprof:oso/9780198565895.003.12. [DOI] [Google Scholar]
- Nazroo JY, Falaschetti E, Pierce M and Primatesta P (2009) Ethnic inequalities in access to and outcomes of healthcare: analysis of the health survey for England. Journal of Epidemiology and Community Health 63, 1022–1027. [DOI] [PubMed] [Google Scholar]
- Nazroo JY, Bhui KS and Rhodes J (2020) Where next for understanding race/ethnic inequalities in severe mental illness? Structural, interpersonal and institutional racism. Sociology of Health & Illness 42, 262–276. [DOI] [PMC free article] [PubMed] [Google Scholar]
- NICE (National Institute for Health and Care Excellence) (2016) Multimorbidity: clinical assessment and management. Available at www.nice.org.uk/guidance/ng56.
- O’Connor DB, Thayer JF and Vedhara K (2021) Stress and health: a review of psychobiological processes. Annual Review of Psychology 72, 663–688. [DOI] [PubMed] [Google Scholar]
- Oh H, Glass J, Narita Z, Koyanagi A, Sinha S and Jacob L (2021a) Discrimination and multimorbidity among Black Americans: findings from the national survey of American life. Journal of Racial and Ethnic Health Disparities 8, 210–219. [DOI] [PubMed] [Google Scholar]
- Oh H, Goehring J, Jacob L and Smith L (2021b) Revisiting the immigrant epidemiological paradox: findings from the American panel of life 2019. International Journal of Environmental Research and Public Health 18, 4619. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Paradies Y, Ben J, Denson N, Elias A, Priest N, Pieterse A, Gupta A, Kelaher M and Gee G (2015) Racism as a determinant of health: a systematic review and meta-analysis. PLoS One 10, 1–48. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pearce J, Rafiq S, Simpson J and Varese F (2019) Perceived discrimination and psychosis: a systematic review of the literature. Social Psychiatry and Psychiatric Epidemiology 54, 1023–1044. [DOI] [PubMed] [Google Scholar]
- Perera G, Broadbent M, Callard F, Chang CK, Downs J, Dutta R, Fernandes A, Hayes RD, Henderson M, Jackson R, Jewell A, Kadra G, Little R, Pritchard M, Shetty H, Tulloch A and Stewart R (2016) Cohort profile of the South London and Maudsley NHS foundation trust biomedical research centre (SLaM BRC) case register: current status and recent enhancement of an electronic mental health record-derived data resource. BMJ Open 6, 1–22. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pillinger T, Mccutcheon RA, Vano L, Mizuno Y, Arumuham A, Hindley G, Beck K, Natesan S, Efthimiou O, Cipriani A and Howes OD (2020) Comparative effects of 18 antipsychotics on metabolic function in patients with schizophrenia, predictors of metabolic dysregulation, and association with psychopathology: a systematic review and network meta-analysis. The Lancet Psychiatry 7, 64–77. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rodrigues M, Wiener JC, Stranges S, Ryan BL and Anderson K (2021) The risk of physical multimorbidity in people with psychotic disorders: a systematic review and meta-analysis. Journal of Psychosomatic Research 140, 110315. [DOI] [PubMed] [Google Scholar]
- Schofield P, Saka O and Ashworth M (2011) Ethnic differences in blood pressure monitoring and control in south-east London. British Journal of General Practice 61, e190–e196. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Singer M, Bulled N, Ostrach B and Mendenhall E (2017) Syndemics and the biosocial conception of health. Lancet 389, 941–950. [DOI] [PubMed] [Google Scholar]
- Sproston K and Mindell J (2006) The Health of Minority Ethnic Groups. The Information Centre. Available at http://www.ic.nhs.uk/webfiles/publications/healthsurvey2004ethnicfull/HealthSurveyforEnglandVol1_210406_PDF.pdf. [Google Scholar]
- StataCorp (2017) Stata Statistical Software: Release 15. College Station, TX: StataCorp LLC. [Google Scholar]
- Stewart R, Soremekun M, Perera G, Broadbent M, Callard F, Denis M, Hotopf M, Thornicroft G and Lovestone S (2009) The South London and Maudsley NHS foundation trust biomedical research centre (SLAM BRC) case register: development and descriptive data. BMC Psychiatry 9, 51. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stubbs B, Koyanagi A, Veronese N, Vancampfort D, Solmi M, Gaughran F, Carvalho AF, Lally J, Mitchell AJ, Mugisha J and Correll CU (2016) Physical multimorbidity and psychosis: comprehensive cross-sectional analysis including 242,952 people across 48 low- and middle-income countries. BMC Medicine 14, 1–12. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Verest WJGM, Galenkamp H, Spek B, Snijder MB, Stronks K and van Valkengoed IGM (2019) Do ethnic inequalities in multimorbidity reflect ethnic differences in socioeconomic status? The HELIUS study. European Journal of Public Health 29, 687–693. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Watkinson RE, Sutton M and Turner AJ (2021) Ethnic inequalities in health-related quality of life among older adults in England: secondary analysis of a national cross-sectional survey. The Lancet Public Health 6, e145–e154. [DOI] [PubMed] [Google Scholar]
- Williams DR, Lawrence JA, Davis BA and Vu C (2019) Understanding how discrimination can affect health. Health Services Research 54(S2), 1374–1388. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Woodhead C, Ashworth M, Schofield P and Henderson M (2014) Patterns of physical co-/multi-morbidity among patients with serious mental illness: a London borough-based cross-sectional study. BMC Family Practice 15, 1–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- World Health Organization (2021) Health Equity. Available at https://www.who.int/health-topics/health-equity.
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to the Information Governance framework and Research Ethics Committee approval in place concerning CRIS data use.