Skip to main content
PMC home page
Clinical Practice and Epidemiology in Mental Health : CP & EMH logoLink to Clinical Practice and Epidemiology in Mental Health : CP & EMH
. 2008 Oct 14;4:23. doi: 10.1186/1745-0179-4-23

Excess mortality in persons with severe mental disorder in Sweden: a cohort study of 12 103 individuals with and without contact with psychiatric services

Dag Tidemalm 1,✉, Margda Waern 2, Claes-Göran Stefansson 3, Stig Elofsson 4, Bo Runeson 1
PMCID: PMC2576252  PMID: 18854034

Abstract

Background

Investigating mortality in those with mental disorder is one way of measuring effects of mental health care reorganisation. This study's aim was to investigate whether the excess mortality in those with severe mental disorder remains high in Sweden after the initiation of the Community Mental Health Care Reform. We analysed excess mortality by gender, type of mental health service and psychiatric diagnosis in a large community-based cohort with long-term mental disorder.

Methods

A survey was conducted in Stockholm County, Sweden in 1997 to identify adults with long-term disabling mental disorder (mental retardation and dementia excluded). The 12 103 cases were linked to the Hospital Discharge Register and the Cause of Death Register. Standardised mortality ratios (SMRs) for 1998–2000 were calculated for all causes of death, in the entire cohort and in subgroups based on treatment setting and diagnosis.

Results

Mortality was increased in both genders, for natural and external causes and in all diagnostic subgroups. Excess mortality was greater among those with a history of psychiatric inpatient care, especially in those with substance use disorder. For the entire cohort, the number of excess deaths due to natural causes was threefold that due to external causes. SMRs in those in contact with psychiatric services where strikingly similar to those in contact with social services.

Conclusion

Mortality remains high in those with long-term mental disorder in Sweden, regardless of treatment setting. Treatment programs for persons with long-term mental disorder should target physical as well as mental health.

Background

Increased risk of premature death, both from natural and unnatural causes, has been reported for all common mental disorders [1]. Explanations for this include behaviour putting life at risk or aimed at ending life [1], poorer quality of medical care [2-6], side effects of neuroleptics [7-11], heavy smoking [12], substance use [1], unhealthy diet [13], a generally unhealthy lifestyle [14], vulnerability to violence of others [15] and effects of the mental disorder itself [16]. Differences in patterns of mortality between men and women and among different psychiatric diagnostic groups have been observed [1,6,15]. Some causes of premature death in this group are related to medical treatment and the social environment; thus, patterns of death causes may vary over time [1,17].

In many countries, emphasis has shifted from hospital-based to community-based mental health services [18,19]. In Sweden, the latest phase in this process was the Community Mental Health Care Reform which was initiated in 1995 [20]. A major feature of this reform was that the responsibility for supplying supported housing and daily occupational activities to persons with severe mental disorder was transferred from psychiatric to social services. The number of individuals with long-term mental disorder residing in the community has thus increased. Therefore, it has become increasingly important to study community-based, rather than hospital-based, cohorts of persons with mental disorder.

Previous studies of Swedish inpatient samples have reported a more than twofold increase in overall mortality in schizophrenia, affective disorders and other mental disorders, as compared to general population controls [6,21-23].

Obviously, mortality rates and excess mortality may reflect the availability and quality of mental health services. Investigating mortality in those with mental disorder is thus one way of measuring effects of mental health care reorganisation. We wanted to investigate whether the excess mortality in those with severe mental disorder remains high after the initiation of the Community Mental Health Care Reform. The main objective of this reform was to instigate social service interventions, and, as a result, many persons with severe mental illness now receive care from social services rather than psychiatric services. Therefore, we wanted to examine possible differences in mortality between those in psychiatric treatment and those with social service contact. Should we expect lower natural cause mortality in one or the other group? Monitoring of physical health could be better in the psychiatric health services as staff are medically trained. On the other hand, social service staff interact with their clients in daily-life settings where they might offer support regarding access to primary health care and lifestyle changes.

In a previous study we examined predictors of suicide within a large community-based cohort of persons with a long-term and disabling mental disorder [24]. This sample is to our knowledge unique, in that it is a large cohort which includes severely mentally ill both with and without psychiatric contact. In the present study, which is based on the same cohort, we quantified excess mortality due to both natural and external causes compared to the general population. Mortality was examined by gender, type of mental health service and inpatient psychiatric treatment history. Further, mortality was compared in diagnostic subgroups among those with a history of psychiatric inpatient care.

Methods

The cohort

The National Board of Health and Welfare, the Stockholm County Council and the Stockholm County Association of Local Authorities conducted a survey in 1997, in order to identify the target population for the Community Mental Health Care Reform. Staff from psychiatry and social services were requested to identify all adult individuals with a long-term disabling mental disorder who were in contact with the services (by personal visit or telephone). At the time of the survey, Stockholm County had 1.8 million inhabitants, of which 1.4 million were aged 18 years or older. This corresponds to about one fifth of the Swedish population 1997. The county contains both rural and urban areas; the latter comprised Stockholm City, the capital and largest city of Sweden (population 730 000 in 1997), and also 24 smaller municipalities (9000 to 84 000 inhabitants 1997).

The inclusion criteria specified residents of Stockholm County aged 18 years or older, with mental disorder causing long-term disability requiring psychiatric care or support from social services. Individuals with mental retardation or dementia and no other mental disorder were excluded. The specified duration of disability was six months or more. These criteria were formulated by the Swedish National Board of Health and Welfare. The survey resulted in a register of 12 267 individuals. Every Swedish citizen has a unique personal identification number. One hundred and sixty-four persons were excluded from the study due to missing data or incorrect identification numbers, yielding a study cohort of 12 103 individuals. Data were collected under the auspices of the government and the study was thus not subject to ethics board review. Social services in six municipalities chose not to participate. Here, data were collected from psychiatric services only. Based on information from other surveys, we estimate that 1000 individuals were missing for this reason. The six municipalities had altogether 225 000 inhabitants aged 18 years or older, corresponding to 16% of Stockholm County's adult population at the time.

The survey questionnaire

For each individual, staff completed a questionnaire that covered sociodemographic variables and variables related to psychiatric and social service interventions. Questionnaires were completed by both social service staff and psychiatric service staff for 2105 individuals. In these instances, only responses from the social service questionnaire were utilised. This approach was chosen by the National Board of Health and Welfare in the original collection of data, as social service interventions were the main objective of the 1995 Community Mental Health Care Reform.

The registers

Data were anonymised for linkage and analysis through the use of encryption. Personal identification numbers for the 12 103 cases were encrypted and linked to the Swedish Hospital Discharge Register (HDR) at the Epidemiological Centre of the National Board of Health and Welfare. This register covers all admissions to inpatient care at all hospitals in the country from the mid-1970s. All discharges from psychiatric inpatient care between January 1, 1990, and December 31, 2000 were identified. The diagnostic groups (ICD-10) in this study were derived exclusively from the HDR 1990–2000. Thus, comparisons of SMRs for different diagnostic groups were made only within the subgroup with a history of psychiatric inpatient care (n = 7740). A subject may have received more than one diagnosis. Encrypted personal identification numbers were linked to the Cause of Death Register (the Epidemiological Centre) in order to identify all deaths that occurred in the cohort between January 1, 1997, and December 31, 2000. The Cause of Death Register includes all deaths among persons registered as residents in Sweden at the time of death. Cause of death is determined by a physician. If the cause of death is unclear, an autopsy is performed. Deaths are classified by the ICD-codes for underlying and contributing causes of death. Swedish national registers are generally considered to be of good quality and are regarded as an invaluable resource in epidemiologic and public health research [25].

Statistics

Standardised mortality ratios (SMRs) and 95% CIs were calculated by a person-years at risk method using PAMCOMP 1.41 [26], for the entire cohort, for the subgroups from psychiatric and social services and for the subgroups with and without psychiatric inpatient care. Person-years at risk 1998–2000 were calculated for each 5-year age group, gender and calendar year. We chose 1998 as the starting point, since cases were entered at different times during 1997. The 95% CIs were calculated assuming a Poisson distribution of the observed number of deaths [27]. The reference population was the population of Stockholm County. The number of excess deaths for each cause of death was calculated by subtracting the expected number of deaths from the observed number of deaths.

Results

Table 1 describes the cohort at baseline. Few were married or had children under 18 at home. Employment was uncommon (6.6%). A majority (64.5%) resided in own or rented home. Other types of housing included lodging (5.5%), group/supported housing (9.0%), institution (7.4%) and homelessness (2.1%). Information on housing was missing in 11.5%.

Table 1.

Baseline characteristics in a community-based cohort with severe mental disorder (n = 12 103)

Background variable Frequency/mean Per centa
Service provider Psychiatry 7468 (61.7%)
Social services only 4635 (38.3%)
Gender Male 5809 (48.0%)
Female 6294 (52.0%)
Mean age 1997 46 (sd 14.4)
Native language Swedish 9298 (76.8%)
Marital status Single 9647 (79.7%)
Married/Cohabiting 1949 (16.1%)
Children under 18 1579 (13.0%)
Open in a new tab

a. All percentages do not add up to 100, due to missing values.

There were 663 deaths in the entire cohort during the three-year study period, corresponding to 5.7% of the men and 5.2% of the women (Table 2). The number of excess deaths in the total cohort was 417, corresponding to 70% and 56% of all deaths in men and women, respectively.

Table 2.

Mortality 1998–2000 in a community-based cohort with severe mental disorder, by gender

Men (n = 5809) Women (n = 6294)
Cause of Deatha ICD-10 chapter Obs Exp SMR (95% CI) Excess deaths Obs Exp SMR (95% CI) Excess deaths
All natural causes I-XVIII 255 89.9 2.8 (2.5 – 3.2) 165 278 138.7 2.0 (1.8 – 2.3) 139
 Neoplasms II 31 27.6 1.1 (0.8 – 1.6) 3 54 41.2 1.3 (1.0 – 1.7) 13
 Diseases of the circulatory system IX 113 38.3 3.0 (2.4 – 3.6) 75 133 59.0 2.3 (1.9 – 2.7) 74
  Ischaemic heart diseases IX 66 20.9 3.2 (2.5 – 4.0) 45 56 23.9 2.3 (1.8 – 3.0) 32
  Cerebrovascular diseases IX 18 7.1 2.5 (1.5 – 4.0) 11 33 15.1 2.2 (1.5 – 3.1) 18
 Diseases of the respiratory system X 24 5.7 4.2 (2.7 – 6.3) 18 30 10.1 3.0 (2.0 – 4.3) 20
 Diseases of the digestive system XI 20 4.3 4.7 (2.9 – 7.2) 16 11 5.0 2.2 (1.1 – 4.0) 6
All external causes XX 79 10.3 7.6 (6.0 – 9.5) 69 51 6.8 7.5 (5.6 – 9.9) 44
 Accidents XX 22 4.7 4.7 (3.0 – 7.1) 17 13 3.5 3.8 (2.0 – 6.4) 10
 Suicide and undetermined (X60-84, Y10-34) XX 56 4.9 11.4 (8.6 – 14.8) 51 36 2.9 12.4 (8.7 – 17.1) 33
  Suicide (X60-84) XX 40 3.8 10.6 (7.6 – 14.4) 36 29 2.3 12.5 (8.4 – 17.9) 27
  Undetermined intent (Y10-34) XX 16 1.1 14.3 (8.2 – 23.2) 15 7 0.6 11.9 (4.8 – 24.5) 6
All Causes 334 100.2 3.3 (3.0 – 3.7) 234 329 145.5 2.3 (2.0 – 2.5) 183
Open in a new tab

a. Only causes of death with 15 or more observed deaths in either gender are presented here, to emphasise the more statistically stable results.

Table 2 shows further standardised mortality ratios (SMRs), demonstrating a threefold increase in men and a twofold increase in women for overall mortality, compared to the general population. To emphasise the more statistically stable results, only causes of death with 15 or more observed deaths in either gender are shown in the table. Mortality was significantly increased in almost all these causes of death, in both genders. Additionally, mortality in men was significantly increased in infectious diseases, endocrine diseases, nervous system diseases, urogenital diseases and unspecified diseases (ICD-10 chapter XVIII). Mortality in mental and behavioural disorders was significantly increased for both genders. There were no cause of death categories with decreased mortality. Overall, the number of excess deaths by natural causes (ICD-10 chapter I-XVIII) was almost three times higher than by external causes (ICD-10 chapter XX) (304 cases vs. 113 cases).

The highest SMRs were observed for external causes (ICD-10 chapter XX), especially suicide and undetermined intent, for both genders. The numbers of excess deaths were highest in suicide including undetermined intent (X60-84, Y10-34), closely followed by ischaemic heart disease, for both genders.

The number of excess deaths due to diseases of the circulatory system was particularly high. Common causes of death in this category included ischaemic heart diseases, cerebrovascular diseases, atherosclerosis (I70, ICD-10), pulmonary embolism and heart failure. Pneumonia, emphysema and chronic obstructive pulmonary disease were the most common causes in the respiratory disease category. Gastric and duodenal ulcer, intestinal diseases, alcoholic liver disease and unspecified gastrointestinal haemorrhage dominated in the digestive category.

The causes of death presented in Table 2 were analysed separately for the subgroups reported by social services only and by psychiatry (Table 3). Overall mortality was similar in the two subgroups. SMRs for suicide including undetermined intent were higher for psychiatric services than for social services, but we cannot conclude a significant difference as the confidence intervals overlapped.

Table 3.

Mortality 1998–2000 in a community-based cohort with severe mental disorder, by service provider

Psychiatric services (n = 7468) Social services only (n = 4635)
Men (n = 3484) Women (n = 3984) Men (n = 2325) Women (n = 2310)
Cause of Death Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI)
All natural causes 109 2.5 (2.1 – 3.0) 110 1.8 (1.5 – 2.2) 146 3.1 (2.7 – 3.7) 168 2.1 (1.8 – 2.5)
 Neoplasms 11 0.8 (0.4 – 1.4) 28 1.3 (0.8 – 1.8) 20 1.4 (0.9 – 2.2) 26 1.4 (0.9 – 2.0)
 Diseases of the circulatory system 49 2.7 (2.0 – 3.6) 50 2.2 (1.7 – 3.0) 64 3.1 (2.4 – 4.0) 83 2.3 (1.8 – 2.8)
  Ischaemic heart diseases 30 3.0 (2.0 – 4.3) 26 2.8 (1.8 – 4.1) 36 3.3 (2.3 – 4.5) 30 2.1 (1.4 – 2.9)
  Cerebrovascular diseases 7 2.2 (0.9 – 4.4) 9 1.6 (0.7 – 3.0) 11 2.8 (1.4 – 5.0 24 2.5 (1.6 – 3.8)
 Diseases of the respiratory system 11 4.4 (2.2 – 7.8) 10 2.5 (1.2 – 4.5) 13 4.1 (2.2 – 7.0) 20 3.3 (2.0 – 5.2)
 Diseases of the digestive system 8 3.5 (1.5 – 7.0) 4 1.8 (0.5 – 4.5) 12 6.0 (3.1 – 10.4) 7 2.6 (1.0 – 5.4)
All external causes 53 8.8 (6.6 – 11.5) 32 8.9 (6.1 – 12.5) 26 6.0 (3.9 – 8.8) 19 5.9 (3.6 – 9.3)
 Accidents 12 4.6 (2.4 – 8.0) 4 2.6 (0.7 – 6.6) 10 4.9 (2.3 – 8.9) 9 4.7 (2.2 – 8.9)
 Suicide and undetermined (X60-84, Y10-34) 40 13.6 (9.7 – 18.5) 26 14.1 (9.2 – 20.6) 16 8.2 (4.7 – 13.2) 10 9.4 (4.5 – 17.3)
  Suicide (X60-84) 30 13.3 (9.0 – 19.0) 23 15.7 (9.9 – 23.5) 10 6.6 (3.1 – 12.1) 6 7.0 (2.6 – 15.2)
  Undetermined intent (Y10-34) 10 14.7 (7.0 – 27.0) 3 7.9 (1.6 – 23.0) 6 13.7 (5.0 – 29.8) 4 19.3 (5.3 – 49.4)
All Causes 162 3.3 (2.8 – 3.8) 142 2.2 (1.9 – 2.6) 172 3.4 (2.9 – 3.9) 187 2.3 (2.0 – 2.6)
Open in a new tab

Causes of death were also analysed for the subgroups with and without psychiatric inpatient treatment during the period 1990–2000 (Table 4). There was greater excess mortality in those with a history of psychiatric inpatient care, both for natural and external causes and in both genders. However, mortality in natural and external causes was significantly increased in both genders compared to the general population also in the group without psychiatric inpatient care. Suicide mortality was substantially lower in those without a history of psychiatric inpatient care.

Table 4.

Mortality 1998–2000 in a community-based cohort with severe mental disorder, by hospital treatment history

Psychiatric inpatient care (n = 7740) No psychiatric inpatient care (n = 4363)
Men (n = 3725) Women (n = 4015) Men (n = 2084) Women (n = 2279)
Cause of Death Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI)
All natural causes 170 3.4 (2.9 – 3.9) 200 2.4 (2.1 – 2.8) 85 2.2 (1.7 – 2.7) 78 1.4 (1.1 – 1.8)
 Neoplasms 17 1.1 (0.6 – 1.7) 40 1.6 (1.1 – 2.1) 14 1.2 (0.7 – 2.0) 14 0.9 (0.5 – 1.5)
 Diseases of the circulatory system 71 3.3 (2.6 – 4.2) 91 2.6 (2.1 – 3.2) 42 2.5 (1.8 – 3.3) 42 1.7 (1.3 – 2.3)
  Ischaemic heart diseases 41 3.5 (2.5 – 4.8) 39 2.8 (2.0 – 3.8) 25 2.7 (1.8 – 4.0) 17 1.8 (1.0 – 2.8)
  Cerebrovascular diseases 9 2.3 (1.0 – 4.3) 19 2.1 (1.3 – 3.3) 9 2.8 (1.3 – 5.3) 14 2.3 (1.2 – 3.8)
 Diseases of the respiratory system 16 5.2 (2.9 – 8.4) 20 3.3 (2.0 – 5.1) 8 3.1 (1.3 – 6.1) 10 2.5 (1.2 – 4.5)
 Diseases of the digestive system 12 4.8 (2.5 – 8.4) 9 3.0 (1.4 – 5.7) 8 4.5 (1.9 – 8.8) 2 1.0 (0.1 – 3.7)
All external causes 68 10.6 (8.2 – 13.4) 40 9.6 (6.9 – 13.1) 11 2.8 (1.4 – 5.0) 11 4.2 (2.1 – 7.4)
 Accidents 17 6.0 (3.5 – 9.6) 6 2.9 (1.1 – 6.3) 5 2.7 (0.9 – 6.4) 7 5.0 (2.0 – 10.3)
 Suicide and undetermined (X60-84, Y10-34) 50 16.1 (11.9 – 21.2) 32 17.4 (11.9 – 24.6) 6 3.3 (1.2 – 7.3) 4 3.7 (1.0 – 9.5)
  Suicide (X60-84) 37 15.5 (10.9 – 21.3) 26 17.7 (11.6 – 26.0) 3 2.2 (0.4 – 6.3) 3 3.5 (0.7 – 10.2)
  Undetermined intent (Y10-34) 13 18.1 (9.6 – 30.9) 6 16.2 (6.0 – 35.3) 3 7.5 (1.5 – 21.9) 1 4.6 (0.1 – 25.5)
All Causes 238 4.2 (3.7 – 4.7) 240 2.7 (2.4 – 3.1) 96 2.2 (1.8 – 2.7) 89 1.5 (1.2 – 1.9)
Open in a new tab

Observed values were generally higher than expected in all subgroups for all analysed causes of death except neoplasms. For neoplasms, observed and expected values were by and large similar (tables 2, 3, 4).

Mortality was generally more increased in younger ages, regardless of treatment setting. Some of the age stratified results are unstable, due to small numbers (Table 5, 6).

Table 5.

Mortality 1998–2000, stratified by age, in a community-based cohort with severe mental disorder, by service provider

Psychiatric services (n = 7468) Social services only (n = 4635)
Men (n = 3484) Women (n = 3984) Men (n = 2325) Women (n = 2310)
Age Groups by Cause of Death Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI)
All natural causes
15–39 y 8 4.8 (2.1 – 9.5) 2 1.8 (0.2 – 6.4) 8 8.2 (3.6 – 16.2) 9 15.8 (7.2 – 29.9)
40–89 y 101 2.4 (2.0 – 2.9) 108 1.8 (1.5 – 2.2) 138 3.0 (2.5 – 3.6) 159 2.0 (1.7 – 2.4)
All external causes
15–39 y 24 13.5 (8.7 – 20.1) 6 13.2 (4.9 – 28.8) 8 7.5 (3.3 – 14.9) 4 16.6 (4.5 – 42.6)
40–89 y 29 6.9 (4.6 – 9.9) 26 8.3 (5.4 – 12.1) 18 5.5 (3.3 – 8.7) 15 5.1 (2.8 – 8.3)
Open in a new tab

Table 6.

Mortality 1998–2000, stratified by age, in a community-based cohort with severe mental disorder, by hospital treatment history

Psychiatric inpatient care (n = 7740) No psychiatric inpatient care (n = 4363)
Men (n = 3725) Women (n = 4015) Men (n = 2084) Women (n = 2279)
Age Groups by Cause of Death Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI) Obs SMR (95% CI)
All natural causes
15–39 y 15 8.4 (4.7 – 13.9) 8 7.2 (3.1 – 14.2) 1 1.2 (0 – 6.6) 3 5.1 (1.0 – 14.8)
40–89 y 155 3.2 (2.7 – 3.7) 192 2.3 (2.0 – 2.7) 84 2.2 (1.7 – 2.7) 75 1.4 (1.1 – 1.7)
All external causes
15–39 y 31 16.1 (11.0 – 22.9) 9 19.9 (9.1 – 37.7) 1 1.1 (0 – 6.1) 1 4.2 (0.1 – 23.2)
40–89 y 37 8.2 (5.8 – 11.3) 31 8.4 (5.7 – 11.9) 10 3.3 (1.6 – 6.1) 10 4.1 (2.0 – 7.6)
Open in a new tab

Within the subgroup with a history of psychiatric inpatient care (n = 7740), substance use disorder (F10-19, ICD-10) was the diagnosis with the highest SMRs for natural causes in both men and women (men: 6.1, 95% CI 4.7–7.8; women: 3.9, 95% CI 2.5–5.8). SMRs for external causes were highest for both genders in those with personality disorder (F60-69; men: 20.5, 95% CI 11.9–32.8; women: 29.1, 95% CI 15.5–49.8) and those with substance use disorder (men: 14.7, 95% CI 9.6–21.5; women: 24.6, 95% CI 13.1–42.0). Suicide mortality (including undetermined intent) was especially high in those with a personality disorder (men: 37.6, 95% CI 21.5–61.0; women: 41.7, 95% CI 20.8–74.7) Remaining SMRs for all the analysed mental disorders (including also psychotic disorders (F20-29), mood disorders (F30-39) and anxiety disorders (F40-48)) ranged between 2.0 and 4.3 for natural causes and between 6.3 and 20.0 for external causes. (Data not shown in table.)

Discussion

To the best of our knowledge, this is the first paper to compare mortality in severely mentally ill with and without psychiatric contact. Mortality in the cohort was at similar high levels as in previous Swedish studies of individuals with severe mental disorder hospitalised during the 1970s, 1980s and beginning of 1990s [6,21-23], regardless of whether treatment was delivered by psychiatric or social services.

Some methodological issues require attention. Firstly, inclusion was determined by service providers and what constitutes a "mental disorder causing long-term disability" may vary in different service settings, which may introduce bias [28]. This approach, however, allowed inclusion of persons without psychiatric contact, which is a major strength of the study. Secondly, diagnostic data are lacking for those with outpatient psychiatric care only. Thirdly, SMRs are strictly speaking only comparable between populations which have exactly the same age distribution. However, research has shown that in practice SMRs may be used to compare different subgroups or cohorts, unless the age distributions are extremely different [29], which is not the case in this study. Fourthly, the results were not adjusted for length of duration of mental disorder. The increased mortality is greatest in the early course of mental disorder, especially in suicide, but possibly also in other causes of death [3,5,22,23,30]. The excess mortality in the cohort is therefore probably somewhat underestimated, due to survivorship bias. This, however, does not affect the conclusions of the study. Fifthly, the quality of the data for potentially confounding socioeconomic variables was insufficient to allow for inclusion in models. It should be noted that a model including socioeconomic variables would have to take into consideration that, e.g., socio-economic status may both lie on the causal pathway from mental disorder to premature death and act as a confounder. Finally, the inclusion criteria were broad, which prevents direct comparison with studies that focus on a specific diagnosis.

SMRs where strikingly similar in those reported by psychiatry or social services, respectively. Longer follow-ups are needed to determine whether differences in mortality in these two groups will emerge over time. Most likely, the increased natural cause mortality in those who had had psychiatric inpatient care indicates an association with severity of the mental disorder. It is also possible that medical comorbidity increases the probability of being admitted for psychiatric inpatient care. Mortality was more pronounced among younger persons, which is consistent with the findings of others [5,22,23,31].

Causes of death

The number of excess deaths from natural causes was threefold that of external causes; this result is in line with previous studies [1,32-34] and underlines the need for health interventions for this vulnerable group. Reasons behind the increased mortality in ischaemic heart diseases in those with a severe mental disorder include smoking, overeating, physical inactivity and side-effects of neuroleptics, including metabolic syndrome. Another explanation may be that persons with severe mental disorder do not receive adequate care, e.g., revascularisation procedures [4,35-37]. Two recent studies show that the latter cause may be avoidable [38,39]. The pronounced mortality in respiratory and digestive diseases was possibly due to heavy smoking and alcohol use, but could also be related to unhealthy diet, a generally unhealthy lifestyle or ineffective medical care [6,12-14]. Mortality in cancer was not elevated compared to the general population. Several previous studies have reported observed values for neoplasms similar to expected or lower in those with schizophrenia and other mental disorders, despite presence of heavy smoking and other risk factors [1,5,23,40,41]. This has led to speculation about protective biological or behavioural factors, especially in schizophrenia [42]. A recent study found some support for an intrinsic protection in schizophrenia, but the same authors reported an increased risk of colon cancer, especially in those taking antipsychotic medications [43].

Psychiatric diagnoses and mortality

The high risk of premature death in those with a substance use disorder is well-known [1,44]. Substance use disorders often co-occur with other diagnosed or undiagnosed mental disorders. Treatment of those with concurrent substance use disorder and other mental disorder is considered difficult; validated treatment strategies are lacking [44-48]. Proposed treatment strategies for this group include integrated mental health and substance abuse treatment [44,48,49] or behavioural treatment for substance abuse developed specifically for people with severe and long-term mental disorders [45]. Those with a personality disorder had a particularly high mortality from external causes, compared to the general population. Borderline personality disorder was the strongest diagnostic predictor of suicide within the same cohort [24]. It has been noted that suicide prevention is particularly challenging in individuals with borderline and other personality disorders [50,51].

Possible interventions

The excess mortality in this group is not only a health care problem, but also a societal problem. It is essential that those with a long-term severe mental disorder actually receive the social support and assistance to which they are legally entitled. Social support can include focus on lifestyle factors and facilitate access to primary care and medical and psychiatric services. At this point it is unclear to what extent an increase in the number of psychiatric beds would affect mortality [52,53].

Causality is often a complex issue, for instance regarding the respective influence of lifestyle factors, lack of appropriate medical care, neuroleptic use and metabolic effects, as well as cardiovascular effects of the disease itself [4,37,54]. It may therefore be difficult to target specific causes of premature death in preventive programs. Consequently, a general, broad range improvement of medical care and social services for this group is possibly the most effective means for reduced mortality on a large scale.

Conclusion

Excess mortality in those with long-term mental disorder remains high in Sweden, regardless of gender, type of mental health service or diagnosis. Treatment programs for persons with long-term mental disorder should target physical as well as mental health.

Competing interests

The authors declare that they have no competing interests.

Authors' contributions

DT co-designed the study, performed the statistical analyses, managed the dataset, and wrote the paper. MW and BR co-designed and cowrote the paper. CGS had the original idea for the study, co-designed it and coordinated management of data. SE was adviser on design and statistics. All authors read and approved the final manuscript.

Contributor Information

Dag Tidemalm, Email: dag.tidemalm@ki.se.

Margda Waern, Email: margda.waern@neuro.gu.se.

Claes-Göran Stefansson, Email: claes-goran.stefansson@socialstyrelsen.se.

Stig Elofsson, Email: stig.elofsson@socarb.su.se.

Bo Runeson, Email: bo.runeson@sll.se.

Acknowledgements

This study is a result of collaboration between Northern Stockholm Psychiatry and the National Board of Health and Welfare, Sweden, who provided necessary resources for the project.

We thank Anna Åberg Wistedt (Northern Stockholm Psychiatry) for valuable suggestions and Torbjörn Johansson (Stockholm County Association of Local Authorities) for important background information about the survey.

References

  1. Harris EC, Barraclough B. Excess mortality of mental disorder. Br J Psychiatry. 1998;173:11–53. doi: 10.1192/bjp.173.1.11. [DOI] [PubMed] [Google Scholar]
  2. Druss BG, Bradford WD, Rosenheck RA, Radford MJ, Krumholz HM. Quality of medical care and excess mortality in older patients with mental disorders. Arch Gen Psychiatry. 2001;58:565–572. doi: 10.1001/archpsyc.58.6.565. [DOI] [PubMed] [Google Scholar]
  3. Hoyer EH, Mortensen PB, Olesen AV. Mortality and causes of death in a total national sample of patients with affective disorders admitted for the first time between 1973 and 1993. Br J Psychiatry. 2000;176:76–82. doi: 10.1192/bjp.176.1.76. [DOI] [PubMed] [Google Scholar]
  4. Lawrence DM, Holman CD, Jablensky AV, Hobbs MS. Death rate from ischaemic heart disease in Western Australian psychiatric patients 1980–1998. Br J Psychiatry. 2003;182:31–36. doi: 10.1192/bjp.182.1.31. [DOI] [PubMed] [Google Scholar]
  5. Mortensen PB, Juel K. Mortality and causes of death in first admitted schizophrenic patients. Br J Psychiatry. 1993;163:183–189. doi: 10.1192/bjp.163.2.183. [DOI] [PubMed] [Google Scholar]
  6. Ringback Weitoft G, Gullberg A, Rosen M. Avoidable mortality among psychiatric patients. Soc Psychiatry Psychiatr Epidemiol. 1998;33:430–437. doi: 10.1007/s001270050076. [DOI] [PubMed] [Google Scholar]
  7. Allison DB, Casey DE. Antipsychotic-induced weight gain: a review of the literature. J Clin Psychiatry. 2001;62(Suppl 7):22–31. [PubMed] [Google Scholar]
  8. Henderson DC, Cagliero E, Gray C, Nasrallah RA, Hayden DL, Schoenfeld DA, Goff DC. Clozapine, diabetes mellitus, weight gain, and lipid abnormalities: A five-year naturalistic study. Am J Psychiatry. 2000;157:975–981. doi: 10.1176/appi.ajp.157.6.975. [DOI] [PubMed] [Google Scholar]
  9. Joukamaa M, Heliovaara M, Knekt P, Aromaa A, Raitasalo R, Lehtinen V. Schizophrenia, neuroleptic medication and mortality. Br J Psychiatry. 2006;188:122–127. doi: 10.1192/bjp.188.2.122. [DOI] [PubMed] [Google Scholar]
  10. Koro CE, Fedder DO, L'Italien GJ, Weiss S, Magder LS, Kreyenbuhl J, Revicki D, Buchanan RW. An assessment of the independent effects of olanzapine and risperidone exposure on the risk of hyperlipidemia in schizophrenic patients. Arch Gen Psychiatry. 2002;59:1021–1026. doi: 10.1001/archpsyc.59.11.1021. [DOI] [PubMed] [Google Scholar]
  11. Koro CE, Fedder DO, L'Italien GJ, Weiss SS, Magder LS, Kreyenbuhl J, Revicki DA, Buchanan RW. Assessment of independent effect of olanzapine and risperidone on risk of diabetes among patients with schizophrenia: population based nested case-control study. BMJ. 2002;325:243–247. doi: 10.1136/bmj.325.7358.243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Brown S, Inskip H, Barraclough B. Causes of the excess mortality of schizophrenia. Br J Psychiatry. 2000;177:212–217. doi: 10.1192/bjp.177.3.212. [DOI] [PubMed] [Google Scholar]
  13. McCreadie RG. Diet, smoking and cardiovascular risk in people with schizophrenia: descriptive study. Br J Psychiatry. 2003;183:534–539. doi: 10.1192/bjp.183.6.534. [DOI] [PubMed] [Google Scholar]
  14. Brown S, Birtwistle J, Roe L, Thompson C. The unhealthy lifestyle of people with schizophrenia. Psychol Med. 1999;29:697–701. doi: 10.1017/S0033291798008186. [DOI] [PubMed] [Google Scholar]
  15. Hiroeh U, Appleby L, Mortensen PB, Dunn G. Death by homicide, suicide, and other unnatural causes in people with mental illness: a population-based study. Lancet. 2001;358:2110–2112. doi: 10.1016/S0140-6736(01)07216-6. [DOI] [PubMed] [Google Scholar]
  16. Empana JP, Jouven X, Lemaitre RN, Sotoodehnia N, Rea T, Raghunathan TE, Simon G, Siscovick DS. Clinical depression and risk of out-of-hospital cardiac arrest. Arch Intern Med. 2006;166:195–200. doi: 10.1001/archinte.166.2.195. [DOI] [PubMed] [Google Scholar]
  17. Brown S. Excess mortality of schizophrenia. A meta-analysis. Br J Psychiatry. 1997;171:502–508. doi: 10.1192/bjp.171.6.502. [DOI] [PubMed] [Google Scholar]
  18. Fakhoury WK, Murray A, Shepherd G, Priebe S. Research in supported housing. Soc Psychiatry Psychiatr Epidemiol. 2002;37:301–315. doi: 10.1007/s00127-002-0549-4. [DOI] [PubMed] [Google Scholar]
  19. Priebe S, Finzen A. On the different connotations of social psychiatry. Soc Psychiatry Psychiatr Epidemiol. 2002;37:47–49. doi: 10.1007/s127-002-8214-3. [DOI] [PubMed] [Google Scholar]
  20. Stefansson CG, Hansson L. Mental health care reform in Sweden, 1995. Acta Psychiatr Scand Suppl. 2001. pp. 82–88. [DOI] [PubMed]
  21. Allebeck P, Wistedt B. Mortality in schizophrenia. A ten-year follow-up based on the Stockholm County inpatient register. Arch Gen Psychiatry. 1986;43:650–653. doi: 10.1001/archpsyc.1986.01800070036005. [DOI] [PubMed] [Google Scholar]
  22. Osby U, Brandt L, Correia N, Ekbom A, Sparen P. Excess mortality in bipolar and unipolar disorder in Sweden. Arch Gen Psychiatry. 2001;58:844–850. doi: 10.1001/archpsyc.58.9.844. [DOI] [PubMed] [Google Scholar]
  23. Osby U, Correia N, Brandt L, Ekbom A, Sparen P. Mortality and causes of death in schizophrenia in Stockholm county, Sweden. Schizophr Res. 2000;45:21–28. doi: 10.1016/S0920-9964(99)00191-7. [DOI] [PubMed] [Google Scholar]
  24. Tidemalm D, Elofsson S, Stefansson CG, Waern M, Runeson B. Predictors of suicide in a community-based cohort of individuals with severe mental disorder. Soc Psychiatry Psychiatr Epidemiol. 2005;40:595–600. doi: 10.1007/s00127-005-0941-y. [DOI] [PubMed] [Google Scholar]
  25. Kamper-Jorgensen F, Arber S, Berkman L, Mackenbach J, Rosenstock L, Teperi J. Part 3: International evaluation of Swedish public health research. Scand J Public Health Suppl. 2005;65:46–84. doi: 10.1080/14034950510033282. [DOI] [PubMed] [Google Scholar]
  26. Taeger D, Sun Y, Keil U, Straif K. A stand-alone windows applications for computing exact person-years, standardized mortality ratios and confidence intervals in epidemiological studies. Epidemiology. 2000;11:607–608. doi: 10.1097/00001648-200009000-00019. [DOI] [PubMed] [Google Scholar]
  27. Sahai H, Khurshid A. Statistics in Epidemiology: Methods, Techniques, and Applications. Boca Raton: CRC Press; 1996. [Google Scholar]
  28. Abrams TE, Vaughan-Sarrazin M, Rosenthal GE. Variations in the associations between psychiatric comorbidity and hospital mortality according to the method of identifying psychiatric diagnoses. J Gen Intern Med. 2008;23:317–322. doi: 10.1007/s11606-008-0518-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Goldman DA, Brender JD. Are standardized mortality ratios valid for public health data analysis? Stat Med. 2000;19:1081–1088. doi: 10.1002/(SICI)1097-0258(20000430)19:8<1081::AID-SIM406>3.0.CO;2-A. [DOI] [PubMed] [Google Scholar]
  30. Lawrence D, Jablensky AV, Holman CD, Pinder TJ. Mortality in Western Australian psychiatric patients. Soc Psychiatry Psychiatr Epidemiol. 2000;35:341–347. doi: 10.1007/s001270050248. [DOI] [PubMed] [Google Scholar]
  31. Laursen TM, Munk-Olsen T, Nordentoft M, Mortensen PB. Increased mortality among patients admitted with major psychiatric disorders: a register-based study comparing mortality in unipolar depressive disorder, bipolar affective disorder, schizoaffective disorder, and schizophrenia. J Clin Psychiatry. 2007;68:899–907. doi: 10.4088/jcp.v68n0612. [DOI] [PubMed] [Google Scholar]
  32. D'Avanzo B, La Vecchia C, Negri E. Mortality in long-stay patients from psychiatric hospitals in Italy – results from the Qualyop Project. Soc Psychiatry Psychiatr Epidemiol. 2003;38:385–389. doi: 10.1007/s00127-003-0646-z. [DOI] [PubMed] [Google Scholar]
  33. Joukamaa M, Heliovaara M, Knekt P, Aromaa A, Raitasalo R, Lehtinen V. Mental disorders and cause-specific mortality. Br J Psychiatry. 2001;179:498–502. doi: 10.1192/bjp.179.6.498. [DOI] [PubMed] [Google Scholar]
  34. Stark C, MacLeod M, Hall D, O'Brien F, Pelosi A. Mortality after discharge from long-term psychiatric care in Scotland, 1977–94: a retrospective cohort study. BMC Public Health. 2003;3:30. doi: 10.1186/1471-2458-3-30. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Young JK, Foster DA. Cardiovascular procedures in patients with mental disorders. JAMA. 2000;283:3198–3199. doi: 10.1001/jama.283.24.3198. [DOI] [PubMed] [Google Scholar]
  36. Druss BG, Bradford DW, Rosenheck RA, Radford MJ, Krumholz HM. Mental disorders and use of cardiovascular procedures after myocardial infarction. JAMA. 2000;283:506–511. doi: 10.1001/jama.283.4.506. [DOI] [PubMed] [Google Scholar]
  37. Osborn DP, Nazareth I, King MB. Risk for coronary heart disease in people with severe mental illness: cross-sectional comparative study in primary care. Br J Psychiatry. 2006;188:271–277. doi: 10.1192/bjp.bp.104.008060. [DOI] [PubMed] [Google Scholar]
  38. Jones LE, Carney CP. Mental disorders and revascularization procedures in a commercially insured sample. Psychosom Med. 2005;67:568–576. doi: 10.1097/01.psy.0000170336.87544.74. [DOI] [PubMed] [Google Scholar]
  39. Petersen LA, Normand SL, Druss BG, Rosenheck RA. Process of care and outcome after acute myocardial infarction for patients with mental illness in the VA health care system: are there disparities? Health Serv Res. 2003;38:41–63. doi: 10.1111/1475-6773.00104. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Amaddeo F, Bisoffi G, Bonizzato P, Micciolo R, Tansella M. Mortality among patients with psychiatric illness. A ten-year case register study in an area with a community-based system of care. Br J Psychiatry. 1995;166:783–788. doi: 10.1192/bjp.166.6.783. [DOI] [PubMed] [Google Scholar]
  41. Felker B, Yazel JJ, Short D. Mortality and medical comorbidity among psychiatric patients: a review. Psychiatr Serv. 1996;47:1356–1363. doi: 10.1176/ps.47.12.1356. [DOI] [PubMed] [Google Scholar]
  42. Goldacre MJ, Kurina LM, Wotton CJ, Yeates D, Seagroat V. Schizophrenia and cancer: an epidemiological study. Br J Psychiatry. 2005;187:334–338. doi: 10.1192/bjp.187.4.334. [DOI] [PubMed] [Google Scholar]
  43. Hippisley-Cox J, Vinogradova Y, Coupland C, Parker C. Risk of malignancy in patients with schizophrenia or bipolar disorder: nested case-control study. Arch Gen Psychiatry. 2007;64:1368–1376. doi: 10.1001/archpsyc.64.12.1368. [DOI] [PubMed] [Google Scholar]
  44. Swartz MS, Swanson JW, Hiday VA, Borum R, Wagner HR, Burns BJ. Violence and severe mental illness: the effects of substance abuse and nonadherence to medication. Am J Psychiatry. 1998;155:226–231. doi: 10.1176/ajp.155.2.226. [DOI] [PubMed] [Google Scholar]
  45. Bellack AS, Bennett ME, Gearon JS, Brown CH, Yang Y. A randomized clinical trial of a new behavioral treatment for drug abuse in people with severe and persistent mental illness. Arch Gen Psychiatry. 2006;63:426–432. doi: 10.1001/archpsyc.63.4.426. [DOI] [PubMed] [Google Scholar]
  46. Goldsmith RJ, Garlapati V. Behavioral interventions for dual-diagnosis patients. Psychiatr Clin North Am. 2004;27:709–725. doi: 10.1016/j.psc.2004.07.002. [DOI] [PubMed] [Google Scholar]
  47. Hayes RA, Andrews N, Baron-Jeffrey M, Conley C, Gridley K, Norman R, Wright G. Service enhancement to a dual-diagnosis population: mental illness/substance abuse (MISA) Qual Manag Health Care. 2003;12:133–150. doi: 10.1097/00019514-200307000-00004. [DOI] [PubMed] [Google Scholar]
  48. Ziedonis DM, Smelson D, Rosenthal RN, Batki SL, Green AI, Henry RJ, Montoya I, Parks J, Weiss RD. Improving the care of individuals with schizophrenia and substance use disorders: consensus recommendations. J Psychiatr Pract. 2005;11:315–339. doi: 10.1097/00131746-200509000-00005. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Hickie IB, Groom GL, McGorry PD, Davenport TA, Luscombe GM. Australian mental health reform: time for real outcomes. Med J Aust. 2005;182:401–406. doi: 10.5694/j.1326-5377.2005.tb06759.x. [DOI] [PubMed] [Google Scholar]
  50. Lambert MT. Suicide risk assessment and management: focus on personality disorders. Curr Opin Psychiatr. 2003;16:71–76. doi: 10.1097/00001504-200301000-00014. [DOI] [Google Scholar]
  51. Paris J. Chronic suicidality among patients with borderline personality disorder. Psychiatr Serv. 2002;53:738–742. doi: 10.1176/appi.ps.53.6.738. [DOI] [PubMed] [Google Scholar]
  52. Nordentoft M, Laursen TM, Agerbo E, Qin P, Hoyer EH, Mortensen PB. Change in suicide rates for patients with schizophrenia in Denmark, 1981–97: nested case-control study. BMJ. 2004;329:261–264. doi: 10.1136/bmj.38133.622488.63. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Salokangas RK, Honkonen T, Stengard E, Koivisto AM. Mortality in chronic schizophrenia during decreasing number of psychiatric beds in Finland. Schizophr Res. 2002;54:265–275. doi: 10.1016/S0920-9964(01)00281-X. [DOI] [PubMed] [Google Scholar]
  54. Correll CU, Frederickson AM, Kane JM, Manu P. Metabolic syndrome and the risk of coronary heart disease in 367 patients treated with second-generation antipsychotic drugs. J Clin Psychiatry. 2006;67:575–583. doi: 10.4088/jcp.v67n0408. [DOI] [PubMed] [Google Scholar]

Articles from Clinical Practice and Epidemiology in Mental Health : CP & EMH are provided here courtesy of Bentham Science Publishers

RESOURCES