Table 1.
Description of the studies included in the meta-analysis
| Author | Cohort | Sex | Follow-up (years) | Age (years) | Quality score* | Exposure | Exposure assessment | Outcome assessment† | Incidence | Adjusted variables† |
|---|---|---|---|---|---|---|---|---|---|---|
| Ayas et al. (8) | NHS | Women | 10.0 | 40–65 | 16 | SD | Questionnaire | Validated questionnaire | 2.95‡ | 1, 2, 3, 4, 5, 7, 8, 9 |
| Kawakami et al. (16) | Electrical Co. | Men | 8.0 | NA | 8 | DIS, DMS | Questionnaire | WHO criteria | 1.68‡ | 1, 2, 3, 4, 5, 8 |
| Nilsson et al. (9) | MPP | Men | 15.2 | Mean 46.2 | 17 | DIS | Questionnaire | Questionnaire and FBG | 4.3%§ | 1, 3, 4, 5, 8 |
| Björkelund et al. (10) | Gothenburg | Women | 32.0 | 38–60 | 15 | SD | Interview | Multiple diagnoses | 8.7%§ | 1 |
| Mallon et al. (11) | Co. of Dalarna | Combined | 10 | 40–70 | 17 | SD, DIS, DMS | Questionnaire | Questionnaire | 9.1%, 6.1%§ | 1, 3, 4, 6, 7, 8, 9 |
| Meisinger et al. (17) | MONICA | Combined | 7.5 | 25–74 | 17 | DIS, DMS | Questionnaire | Self-reported validated | 3.85, 2.18‡ | 1, 2, 3, 4, 5, 8 |
| Yaggi et al. (12) | MMAS | Men | 13–17 | 40–70 | 15 | SD | Questionnaire | Evidence of diagnosis | 6.11‡ | 1, 3, 6, 8 |
| Gangwisch et al. (13) | NHANES I | Combined | 8–10 | 32–86 | 16 | SD | Questionnaire | Multiple methods | 4.8%§ | 1, 2, 4, 6, 7, 8 |
| Hayashino et al. (15) | HIPOP-OHP | Combined | 4.2 | 19–69 | 17 | SD, DIS, DMS | Questionnaire | Multiple methods | 3.5%§ | 1, 2, 3, 6 |
| Beihl et al. (14) | IRAS | Combined | 5.0 | 40–69 | 15 | SD | Questionnaire | OGTT | 16.3%§ | 1, 3, 5, 6, 8 |
*Data from ref. 18.
†1, age, body mass, and sex (when combined); 2, leisure-time physical activity; 3, smoking; 4, alcohol consumption; 5, family history of diabetes, hypertension, and high cholesterol; 6, hypertension; 7, depression; 8, socioeconomic variables; 9, snoring.
‡Per 1,000 person-years.
§Cumulative incidence. DIS, difficulty in initiating sleep; DMS, difficulty in maintaining sleep; FBG, fasting blood glucose; NHANES I, National Health and Nutrition Examination Survey I; NHS, Nurses Health Study; HIPOP-OHP, High-Risk and Population Strategy for Occupational Health Promotion; IRAS, Insulin Resistance Atherosclerosis Study; MMAS, Massachusetts Male Aging Study; MONICA, Monitoring Trends and Determinants of Cardiovascular Disease; MPP, Malmo Preventive Project; NA, not applicable; OGTT, oral glucose tolerance test. SD, sleep duration; WHO, World Health Organization.