TABLE 1—
Covariates at Phase 3 and Prevalence and OR (95% CI) for Associations With Major Depressive Disorder at Phase 5: Whitehall II Study, London, UK, 1988–1999
| Major Depressive Disorder at Phase 5 |
|||
| Covariate | Proportion (No.) | Prevalence (No.) | ORa (95% CI) |
| Age, y | |||
| 45–54 | 79.2 (3123) | 4.45 (139) | 1.00 (Ref) |
| 55–64 | 20.8 (819) | 2.32 (19) | 0.51 (0.32, 0.83) |
| Gender | |||
| Male | 74.0 (2919) | 3.56 (104) | 1.00 (Ref) |
| Female | 26.0 (1023) | 5.28 (54) | 1.50 (1.07, 2.10) |
| Employment grade | |||
| Administrative | 42.4 (1671) | 2.87 (48) | 1.00 (Ref) |
| Executive or professional | 46.9 (1847) | 4.87 (90) | 1.62 (1.13, 2.33) |
| Clerical or other | 10.8 (424) | 4.72 (20) | 1.50 (0.85, 2.67) |
| Age of completion of education, y | |||
| ≤ 16 | 29.9 (1178) | 3.48 (41) | 1.00 (Ref) |
| 17–18 | 24.9 (980) | 4.49 (44) | 1.26 (0.81, 1.94) |
| > 18 | 45.3 (1784) | 4.09 (73) | 1.11 (0.74, 1.65) |
| Marital status | |||
| Married or cohabiting | 78.8 (3107) | 3.73 (116) | 1.00 (Ref) |
| Single | 13.9 (547) | 4.39 (24) | 1.07 (0.68, 1.70) |
| Widowed, divorced, or separated | 7.31 (288) | 6.25 (18) | 1.61 (0.96, 2.73) |
| Smoking | |||
| Never | 49.3 (1942) | 3.55 (69) | 1.00 (Ref) |
| Ex-smoker | 36.6 (1444) | 4.57 (66) | 1.41 (0.99, 1.99) |
| Current | 14.1 (556) | 4.14 (23) | 1.17 (0.72, 1.90) |
| Alcohol intake, units/wk | |||
| None | 15.8 (624) | 3.04 (19) | 1.00 (Ref) |
| 1–14 (women)/1–21 (men) | 67.7 (2669) | 4.20 (112) | 1.47 (0.89, 2.42) |
| ≥ 15 (women)/ ≥ 22 (men) | 16.5 (649) | 4.16 (27) | 1.46 (0.80, 2.67) |
| Physical activity | |||
| Vigorous | 54.6 (2153) | 3.11 (67) | 1.00 (Ref) |
| Moderate | 31.8 (1252) | 5.35 (67) | 1.69 (1.19, 2.40) |
| None | 13.6 (537) | 4.47 (24) | 1.40 (0.86, 2.30) |
| Confiding and emotional support | |||
| High | 32.9 (1298) | 4.08 (53) | 1.00 (Ref) |
| Intermediate | 31.5 (1243) | 4.26 (53) | 1.12 (0.76, 1.66) |
| Low | 35.5 (1401) | 3.71 (52) | 1.09 (0.74, 1.61) |
| Social network | |||
| High | 36.6 (1441) | 4.23 (61) | 1.00 (Ref) |
| Medium | 37.3 (1470) | 4.01 (59) | 0.93 (0.65, 1.35) |
| Low | 26.2 (1031) | 3.69 (38) | 0.88 (0.58, 1.33) |
| Longstanding physical illness | |||
| No | 67.2 (2648) | 3.29 (87) | 1.00 (Ref) |
| Yes | 32.8 (1294) | 5.49 (71) | 1.77 (1.28, 2.45) |
| GHQ caseness at phase 1 | |||
| Noncase | 72.9 (2859) | 3.11 (75) | 1.00 (Ref) |
| Case | 27.1 (1065) | 6.48 (72) | 2.05 (1.48, 2.84) |
| GHQ caseness at phase 2 | |||
| Noncase | 70.4 (2562) | 2.93 (75) | 1.00 (Ref) |
| Case | 29.6 (1076) | 6.69 (72) | 2.30 (1.65, 3.21) |
| GHQ caseness at phase 3 | |||
| Noncase | 77.9 (3007) | 2.86 (86) | 1.00 (Ref) |
| Case | 22.1 (855) | 7.60 (65) | 2.63 (1.88, 3.67) |
Note. CI = confidence interval; GHQ = General Health Questionnaire; OR = odds ratio. The sample size was n = 3942.
a
ORs for covariates are adjusted for age and gender. Age and gender are mutually adjusted.