Table 1.
Summary of the Qualified Studies
| No | Author and Year | Study Design | Study Group | Psychosocial Factors Affecting Adherence to Diabetes Treatment | Limitations |
|---|---|---|---|---|---|
| 1 | Rao D et al, 202017 | A longitudinal study | 287 black adult patients with T2DM (56.3% male) aged 52.6±12.03 | Physician communication, beliefs about medicines, self-efficacy, depression, illness perception | - Small sample size - No regression models to assess predictors of adherence |
| 2 | Saffari M et al, 201918 | A longitudinal study | 793 patients with T2DM (55.0% male) aged 70.21± 15.10 years. | Social support, religiosity, religious coping | - Social support and religious coping were context-based - No assessment of other factors associated with religiosity, (locus of control, spiritual coping, and self-efficacy) |
| 3 | Adisa R et al, 201719 | A prospective cross-sectional study | 200 patients with T2DM aged 63.7 ± 12.4 years | Access to family support, monthly income, medicine affordability | - Self-report measure (risk of bias)- No assessment of availability and influence of structural support (knowledge and attitudinal barriers on outcome) - A cross-sectional study design |
| 4 | Smalls BL et al, 201520 | A cross-sectional study | 615 adults with T2DM (61.6% male), 53.6% in aged 45–64 years, 53.6 non-Hispanic Black | Social support, social cohension, comorbidities, age 65+, hispanic race, health insurance – medicaid, being employed, food insecurity | - A convenience sample from only the southeastern United States - A cross-sectional study design |
| 5 | Tiv et al, 201221 | A cross-sectional study | 3637 patients with T2DM aged 65.0 ±11.1 years (54.4% male) | Family and social support, age 65–84 years, professional activity, financial difficulties, presence of microvascular or macrovascular complications, | - Use of self-report data on medication adherence -Cross sectional study |
| 6 | Osborn CY and Egede LE, 201222 | A cross-sectional study | 139 patients with T2DM in mean age 62.7 ±11.9 years (71.9% male), 41.4% African American | Social support, depressive symptoms | - No subgroups analysis (gender, race/ethnicity, health literacy status) - The PHQ-9 used to quantify depressive symptoms (other studies have shown that the tool overestimates the prevalence of major depression in samples of people with diabetes and other comorbidities) - A cross-sectional study design |
| 7 | Bouldin ED et al, 201723 | A cross-sectional study | 253 adults age 30–70 with poorly controlled diabetes (45% white, 25% black, and 43% Hispanic) | Caregiver support | - Risk of bias (social desirability) - Using broad definition of having acaregiver (periodic or minimal assistance) -No information about how long the caregiver had provided assistance, what types of support the caregiver provided, the quality of care, or the caregiver’s confidence in promoting self-care - Small number of patients with caregiver - A cross-sectional study design |
| 8 | Song Y et al, 201324 | A descriptive observational study | 83 Korean Americans with T2DM in mean age 56.5 ± 7.9 years (57.8% male). | Unmet needs for social support, self-efficacy, age | - Study was conducted on a relatively small and homogeneous sample from one ethnic minority group -Social support assessed by measuring the patients’ perceptions |
| 9 | Watkins YJ et al, 201325 | A cross-sectional study | 132 African American adults with T2DM (male 33%), in mean age 52.2±12.8 | Spirituality, religion, age, gender, income | -Study focused on African American adults -Self-reported data -No consideration of religious affiliations and associations and the impact they have on health behaviors (smoking, alcohol) - A cross-sectional study design |
| 10 | Anderson JR et al, 201626 | An observational study | 117 couples in which one partner was diagnosed with T2DM (male patients 57.3%), mean age of patients 57.44 ± 9.83 years | Dietary adherence: diabetes stress, depressive symptoms Exercise adherence: comorbidities, T2DM duration, depressive symptoms |
-The sample was fairly homogenous with respect to race/ethnicity, education, and geographic location-self-report measures |
| 11 | Bell RA et al, 201027 | A cross-sectional study | 696 patients with T2DM divided into 2 groups: with depression (n=586, aged 74.1 ± 5.3 years, 64.6% male) and without depression (n=110, aged 74.1 ± 5.9 years, 35.4% male) | Depression | -A cross-sectional study -Self-report measures |
| 12 | Zhang Y et al, 201528 | A cross-sectional study | 2538 patients with T2DM (53% male) aged 56.4 ± 10.5 years | Depression | - Patients from metropolitan hospital-based clinics only - No assessment of marital status and income which might have prognostic significance for depression -The PHQ-9 used to quantify depressive symptoms - No formal psychiatric examination to confirm a diagnosis of major depression |
| 13 | Carper MM et al, 201429 | A cross-sectional study | 146 patients with T2DM (57.5% male) aged 56.01 ± 9.28 years | Depression, diabetes distress, quality of life (domains: personal relationships, environmental, achievement, psychosocial growth) | - The ratio of participants to measure items (9:1) - High levels of depression severity and diabetes distress of patients - A cross-sectional study design - recruited primarily non-Hispanic White limiting generalizability of the findings to other racial/ethnic groups |
| 14 | Sweileh WM et al, 201430 | A cross-sectional study | 294 patients with T2DM (44.2% male), 73.5% ≤65 years, | Depression | - A cross-sectional study design -Self-report measures - No multivariate analysis of factors associated with adherence |
| 15 | Zuberi SI et al, 201131 | A cross-sectional study | 286 patients with T2DM (44.8% male) aged 31–60 years | Depression | - A cross-sectional study design - No assessment of educational status and household income - Self-report measures |
| 16 | Derakhshan Shahrabad H et al, 201832 | A prospective observational cohort study | 24 females with T2DM (aged 20–40 years) divided into 2 groups: control (n=12) and experimental (n=12) Intervention:12 weeks Lazarus multimodal psychotherapy |
Depression, anxiety | -No adherence assessment - No formal psychiatric examination to confirm a diagnosis of depression -Self-reported data - No multivariate analysis of factors associated with adherence |
| 17 | Ciebiada M et al, 201733 | An observational study | 55 patients with T2DM (34.5% male) aged 73.7 ± 4.4 years | Depression | - No standardised tool to assess adherence - No formal psychiatric examination to confirm a diagnosis of depression -Self-reported data - No multivariate analysis of factors associated with adherence |
| 18 | Górska-Ciebiada M et al, 201734 | An observational study | 82 patients with T2DM and depressive syndrome aged >65 years | Depression | -A single-centre study with a small sample size - Self-reported data - No standardised tool to assess adherence |
| 19 | Akpalu J et al, 201835 | A cross-sectional study | 400 patients with T2DM (21.5% male) aged 52.7 ± 8.7 years | - | - A cross-sectional study design - Patients were selected from a specialized tertiary hospital in urban Ghana - No standardised tool to assess adherence |
| 20 | Linetzky B et al, 201736 | A multinational prospective observational cohort study | 4341 patients with T2DM in mean age 61.77 ± 11.02 years (50% male) | Diabetes duration, high country income, private insurance status, insulin treatment regimen, communication, diabetes-related distress | - A cross-sectional study design - No standardised tool to assess adherence -Self-reported data |
| 21 | Ratanawongsa N et al, 201337 | A cross-sectional study | 9377 patients with T2DM in mean age 59.5±9.8 years (48.3% male) | Communication | - A cross-sectional study design - Risk of recall bias - Only CMG use to assess adherence and does not evaluate early stages of adherence for newly prescribed medications (primary nonadherence) - Limited pharmacy data on insulin use by patients |
| 22 | Kirkman MS et al, 201538 | An observational study | 218,384 patients with T2DM (47% male) aged 64.9±4.8 years | TYPE of therapy (new or continuing), age, gender, education, income, geographic region, prescriber specialization, prescription factors (pill burden, prescription drug channel, out of pocket costs) | - No race/ethnicity data - No primary nonadherence (not filling an initial prescription for a medication) assessment - MPR measures only refill behavior and not actual medication taking |
| 23 | Xie Z et al, 202039 | A secondary data analysis of a 24-week randomized controlled trial (RCT) | 148 patients with T2DM and hypertension (59.5% male), 52.7% aged ≥64 years | Perceived health status, self-efficacy, older age, gender, living status, diabetes duration | - Self-reported data |
| 24 | Mutyambizi C et al, 202040 | A cross-sectional study | 396 patients with T2DM aged 41–60 years (39% male), 35% were African | Older age, being non-African, gender, professional activity, marital status, education | - A cross-sectional study design - The risk of social desirability bias during the face-to-face interviews - Data collected in two hospitals |
| 25 | Alfian SD et al, 201941 | An observational retrospective inception cohort study | 6669 patients with T2DM (55.1% Male) aged 63.2+11.3 years | Older age, type of prevention, the prescription of diuretics, beta-blocking agents or calcium channel blockers as initial drug class, gender | - Assessment of non-adherence and non-persistence based on drug dispensing (risk of underestimate true rates, because of not taking all the drugs collected at the pharmacy) - Coexisting hypertension |
| 26 | Mahfouz EM and Awadalla HI, 201142 | A cross-sectional analytic study | 206 patients with T2DM (39.8% of male) aged 54±6.3 years | Self-monitoring: older age, education dietary adherence: occupation, duration of diabetes |
- A cross-sectional study design - Self-reported data |
| 27 | Mendes R et al, 201943 | A cross-sectional study | 94 patients with T2DM in mean age of 75.2 ±6.7 years (46.8% male) | Anxiety, insulin use | - A cross-sectional study design - Self-reported data |
| 28 | Akturk U et al, 201844 | A descriptive observational study | 264 patients with T2DM aged 52.33±14.6 years (39.4% male) | Education level, acceptance of illness, professional activity, income, support for care, smoking, comorbidities | - Recruited only the patients registered in the Başharık Family Health Center - Self-reported data |
| 29 | Alyami M et al, 201945 | An observational study | 115 Muslim Saudi nationals patients with T2DM, in mean age 56±12.43 years (58% male) | Age, sense of coherence, illness perception – consequences and illness identity | - Participants were recruited from a single diabetes outpatient clinic using convenience sampling - Self-reported data |
| 30 | Özkaptan BB et al, 201946 | A cross-sectional, descriptive study | 200 patients with T2DM in mean age 53.87 ± 11.3 years (37.5% male) | Age, BMI, HbA1c, fasting blood glucose, postprandial blood glucose, acceptance of illness | - A cross-sectional study design - Self-reported data - No analysis of the correlation between acceptance of illness and adherence |
| 31 | Can S et al, 202047 | A cross-sectional, study | 133 patients with T2DM in mean age 57.3±11.7 years (37.6% male) | Acceptance of illness in domain diet, exercise, foot care and total | - A cross-sectional study design - Self-reported data - No analysis of the correlation between acceptance of illness and adherence - No standardised tool to assess adherence |
| 32 | Dhippayom T and Krass I, 201548 | An observational cross-sectional study | 543 T2DM patients (57.6% male) aged 63.0 ± 10.6 years | Age, knowledge of diabetes and treatment, beliefs about medicines - specific-concern, reported having difficulty in paying for medication, insulin use, polypharmacy | - A cross-sectional study design - Self-reported data |
| 33 | Graça Pereira M et al, 201949 | An cross-sectional study | 387 Caucasian patients diagnosed with T2DM (58.1% male) in mean age 59.2 years | Bieliefs about medicines (needs), illness perception (concerns, consequences, personal control, treatment control, emotional response) | - A cross-sectional study design - Self-reported data |
| 34 | Yoel U et al, 201350 | An observational cohort study | 101 low adherent Bedouin patients with diabetes, hypertension and lipid metabolic disorder aged 49.7 ± 12.0 years (51.5% male) and 99 high adherent patients aged 55.3 ± 12.4 years (36.4% male) | Beliefs about medicines | - Coexisting lipid metabolic disorder and hypertension - Questions about the clinic team were asked to patients at the clinic - Self-reported data - Study focused only on Bedouin - No multivariate analysis of factors associated with adherence |
| 35 | Rosland AM et al, 201551 | A community-based participatory study | 108 patients with T2DM divided into 2 groups: intervention (n=56, 25% male, aged 50.2 ±10.2 years) and control (n=52, 32.7% male, aged 56.4 ±12.3 years) Intervention: The six-month intervention included CHW-delivered group diabetes management classes, home visits and accompaniment to physician appointments to model activated participation |
Family and friends support, CHW support | - A cross-sectional study design - Study participants were low-income, racial/ethnic minority adults - Assessment of only one type of diabetes social support(positive support from family and friends) - Self-reported data - No standardised tool to assess adherence |
| 36 | Rosland AM et al, 201452 | An cross-sectional study | 13,366 patients with T2DM (51% male) aged 59±10 years | Healthful eating and physical activity: social support, emotional support | - A cross-sectional study design - Self-reported data - Analysis of 18 multivariable models and risk of one or more false positive findings |
Abbreviations: T2DM, type 2 diabetes mellitus; BMI, body mass index; HbA1c, glycated hemoglobin; CHW, community-based health worker; PHQ-9, Patient Health Questionnaire-9; MPR, Medication Possession Ratio; CMG, Continuous Measure of Medication Gaps.