Table 1. Characteristics of the included studies.
| Study | Country | Design | Population | Sample size | Mean age | Male | Definition of PreD | No. of people with PreD | Diagnosis for depression | No. of subjects with depression | Variables adjusted |
|---|---|---|---|---|---|---|---|---|---|---|---|
| years | % | ||||||||||
| Paile 2007 | Finland | CS | Community-derived population | 2003 | 61.5 | 46.3 | IFG and/or IGT | 635 | BDI | 383 | Age, sex, BMI, and prevalence of CVD |
| Knol 2007 | The Netherlands | CS | Community-derived population | 4747 | 39.4 | 46.7 | IFG | 671 | SCL-90 | 916 | Age, sex, education, BMI, smoking, alcohol drinking, physical exercise, and number of chronic diseases |
| Holt 2009 | UK | CS | Community-derived population | 2995 | 66.1 | 52.7 | IFG and/or IGT | 996 | HAD-D | 161 | Age, sex, BMI, smoking, social class and alcohol consumption |
| Aujla 2009 | UK | CS | Community-derived population | 6009 | 58 | 47.4 | IFG and/or IGT | 855 | WHO-5 | 1231 | Age, sex, BMI, smoking, WC, exercise, and Index of Multiple Deprivation score |
| Gale 2010 | The US | CS | US veterans | 4293 | 38.8 | 100 | IFG | 492 | MMPI | 276 | Age, ethnicity, clinical characteristics, and health behaviors, intelligence, educational attainment, and household income |
| Poongothai 2010 | India | CS | Community-derived population | 23787 | 38.1 | 49.3 | IFG | 7657 | PHQ-9 | 3391 | Age, sex, BMI, hypertension, and SES |
| Bouwman 2010 | The Netherlands | CS | Community-derived population | 2667 | 53.4 | 47.3 | IFG and/or IGT | 425 | CES-D | 348 | Age, sex, education, family history of DM, TG, HDL-C, TC, hypertension, smoking, and WC |
| Tsai 2012 | China | CS | Community-derived population | 9561 | 46.3 | 61.1 | IFG and/or IGT | 2440 | BSRS-50 | NR | Age, sex, BMI, marital status, educational level, hypertension, SCr, TG, and HDL-C, current smoking and alcohol use, regular exercise, and family history of DM |
| Sun 2015 | China | CS | Community-derived population | 229047 | 57.4 | 34.4 | IFG and/or IGT | 59512 | PHQ-9 | 10994 | Age, sex, BMI, HbA1c, physical activity, smoking and alcohol drinking status, education level, occupation and marital status |
| Natasha 2015 | Bangladesh | CS | Community-derived population | 2293 | 41.8 | 36.7 | IFG and/or IGT | 197 | MARDS | 351 | Age, sex, marital status, BMI, waist to hip ratio, physical activity, and hypertension |
| Albertorio 2017 | The US | CS | Community-derived population | 7717 | 53.5 | 49.3 | IFG or HbA1c (5.7~6.4%) | 2024 | PHQ-9 | 216 | Age, sex education, race-ethnicity, poverty, and BMI |
| Breyer 2019 | Austria | CS | Community-derived population | 11014 | 44.9 | 47.8 | IFG or HbA1c (5.7~6.4%) | 2225 | HAD-D | NR | Age, sex, smoking, LDL-C, HDL-C, and TG |
| Xu 2021 | China | CS | Community-derived population | 1728 | 40.1 | 38.4 | IFG and/or IGT | 536 | PHQ-9 | 83 | Age, sex, BMI, physical activity at work, and systolic pressure |
| Cui 2021 | China | CS | Community-derived population | 3300 | 40.6 | 40.2 | IFG and/or IGT | 771 | ZSDS | 179 | Age, sex, area, education, marriage, monthly income, occupation |
| Yang 2023 | Korea | CS | Community-derived population | 4063 | 52 | 0 | IFG or HbA1c (5.7~6.4%) | 1577 | PHQ-9 | 261 | Age, SES, alcohol drinking, smoking, BMI, menopausal status |
| de Ritter 2023 | The Netherlands | CS | Community-derived population | 7639 | 58.8 | 50 | IFG and/or IGT | 1141 | PHQ-9 | 328 | Age, sex, education, alcohol use, smoking, BMI, physical activity, and healthy diet score, total cholesterol-to-HDL cholesterol ratio, systolic BP, and medications |
PreD, prediabetes; CS, cross-sectional; IFG, impaired fasting glucose; IGT, impaired glucose tolerance; HbA1c, glycolated hemoglobin; BDI, Beck Depression Inventory; SCL-90, Symptom Check List 90; HAD-D, Hospital Anxiety and Depression–Depressive symptoms; WHO-5, World Health Organization Five Wellbeing Index 5; MMPI, Minnesota Multiphasic Personality Inventory; PHQ-9, Patient Health Questionnaire 9 items; CES-D, Centre for Epidemiologic Studies Depression Scale; BSRS-50, Questionnaire of Brief Symptoms Rating Scale; MARDS, Montgomery Asberg Depression Rating Scale; CIDI, Composite International Diagnostic Interview; ZSDS, Zung self-rating depression scale; BMI, body mass index; CVD, cardiovascular disease; WC, waist circumference; SES, socioeconomic status; DM, diabetes mellitus; TG, triglyceride; HDL-C, high-density lipoprotein cholesterol; TC, total cholesterol; SCr, serum creatinine; LDL-C, low-density lipoprotein cholesterol; BP, blood pressure.