Table 2.
Hazard ratio (95% confidence intervals) of ESRD according to sleep duration: Singapore Chinese Health Study (n = 63,147, 1,143 cases)
| Daily sleep duration |
|||||
|---|---|---|---|---|---|
| ≤ 5 hours | 6 hours | 7 hours | 8 hours | ≥ 9 hours | |
| Person-years | 97,496 | 247,706 | 354,731 | 292,877 | 68,340 |
| Cases | 152 | 234 | 325 | 328 | 104 |
| HR (95% CI)a | 1.53 (1.26–1.86) | 0.99 (0.84–1.18) | 1.00 | 1.21 (1.04–1.42) | 1.50 (1.20–1.88) |
| HR (95% CI)b | 1.43 (1.18–1.74) | 1.00 (0.84–1.18) | 1.00 | 1.19 (1.02–1.39) | 1.28 (1.03–1.60) |
The estimates were generated using Cox proportional hazards models.
Hazard ratios were adjusted for age at recruitment (years), gender, dialect (Cantonese, Hokkien), education level (no formal education, primary school, ≥ secondary school), year of interview (1993–1995, 1996–1998), body mass index (kg/m2), physical activity (any weekly moderate activity, vigorous activity or strenuous sports lasting at least 30 minutes: yes or no), smoking status (never-, ever-smokers), alcohol use (none, monthly, weekly, daily), total energy intake (kcal/day), total protein intake (g/day, quartiles), red meat consumption (g/day, quartiles) and coffee consumption (none to < 1 cup/day, 1 cup/day, ≥ 2 cups/day), weekly ginseng intake (yes or no), weekly medicinal soup intake (yes or no) and incense use (current users, non-current users).
In addition to above, hazard ratios were adjusted for self-reported history of physician-diagnosed hypertension, diabetes, coronary artery disease and stroke (yes or no).