Table 2.
Hazard ratiosa (95% CI) of incident hepatic steatosis (regardless of fibrosis score) by sleep duration and subjective sleep quality
| Sleep duration (hr) | P for trend | Subjective sleep quality | ||||||
| ≤5 | 6 | 7 | 8 | ≥9 | Good | Poor | ||
| PY | 78,095 | 204,972 | 216,532 | 97,316 | 21,668 | 498,010 | 120,573 | |
| Incident cases | 4,128 | 10,567 | 9,326 | 3,244 | 552 | 22,982 | 4,835 | |
| Incidence density (/103 PY) | 52.9 | 51.6 | 43.1 | 33.3 | 25.5 | 46.1 | 40.1 | |
| Multivariable-adjusted HR | ||||||||
| Model 1 | 1.24 (1.19–1.28) | 1.09 (1.06–1.12) | 1.0 | 0.97 (0.94–1.01) | 0.94 (0.86–1.03) | <0.001 | 1.0 | 1.07 (1.04–1.11) |
| Model 2 | 1.19 (1.14–1.23) | 1.07 (1.04–1.10) | 1.0 | 0.98 (0.94–1.02) | 0.95 (0.87–1.03) | 0.002 | 1.0 | 1.00 (0.97–1.04) |
| Model 3 | 1.07 (1.03–1.11) | 1.02 (0.99–1.05) | 1.0 | 0.99 (0.96–1.04) | 1.00 (0.91–1.09) | 0.001 | 1.0 | 1.05 (1.02–1.09) |
| Model 4 | 1.10 (1.05–1.14) | 1.03 (1.00–1.06) | 1.0 | 0.97 (0.93–1.01) | 0.95 (0.87–1.04) | <0.001 | 1.0 | 1.03 (1.00–1.07) |
| Time-dependent model 1b | 1.20 (1.15–1.25) | 1.07 (1.04–1.10) | 1.0 | 0.97 (0.93–1.01) | 0.88 (0.80–0.97) | <0.001 | 1.0 | 0.97 (0.94–1.01) |
| Time-dependent model 2b | 1.06 (1.02–1.10) | 1.01 (0.99–1.04) | 1.0 | 0.99 (0.95–1.03) | 0.95 (0.86–1.04) | 0.001 | 1.0 | 1.02 (0.99–1.06) |
| Time-dependent model 3b | 1.16 (1.06–1.15) | 1.03 (1.001–1.06) | 1.0 | 0.98 (0.94–1.02) | 0.91 (0.83–1.001) | <0.001 | 1.0 | 1.00 (0.96–1.03) |
BMI, body mass index; CI, confidence interval; HR, hazard ratio; PY, person-years.
Estimated from parametric proportional hazard models. Multivariable model 1 was adjusted for age and sex; model 2: model 1 plus adjustment for center, year of screening examination, season, alcohol consumption, smoking, physical activity, total energy intake, marital status, season, education level, depression, history of diabetes, and history of hypertension; model 3: model 2 plus adjustment for BMI; and model 4: model 2 plus adjustment for waist circumference.
Estimated from parametric proportional hazard models with sleep duration, smoking, alcohol consumption, physical activity, total energy intake, marital status, season, depression, history of diabetes, and history of hypertension as time-dependent categorical variables and baseline age, sex, center, year of screening examination, education level as time-fixed variables: time-dependent model 2; time-dependent model 1 plus adjustment for BMI as time-varying variable; time-dependent model 3; time-dependent model 1 plus adjustment for waist circumference as time-varying variable.