Table 4.
Associations (HR (95% CI)) between weekend sleep duration and mortality in blacks and whites (age 40 – 79) in the Southern Community Cohort Study, by race
| Weekend sleep duration, hour | ||||
|---|---|---|---|---|
| <6 | 6 | 7–8 | 9+ | |
| white | ||||
| All-cause mortality | ||||
| No. of death (%) | 356 | 483 | 1086 | 377 |
| Model 1 | 1.78 (1.57,2.00) | 1.32 (1.18, 1.47) | ref | 1.21 (1.08, 1.36) |
| Model 2 | 1.25 (1.11, 1.42) | 1.07 (0.96, 1.19) | ref | 1.12 (0.99, 1.26) |
| Model 3 | 1.18 (1.04, 1.33) | 1.02 (0.92, 1.14) | ref | 1.06 (0.94, 1.19) |
| CVD mortality | ||||
| No. of death (%) | 104 | 134 | 262 | 108 |
| Model 1 | 2.25 (1.79,2.83) | 1.54 (1.25, 1.89) | ref | 1.48 (1.19, 1.86) |
| Model 2 | 1.59 (1.26,2.01) | 1.25 (1.02, 1.54) | ref | 1.37 (1.10, 1.72) |
| Model 3 | 1.47 (1.16, 1.85) | 1.20 (0.97, 1.48) | ref | 1.28 (1.02, 1.61) |
| Cancer mortality | ||||
| No. of death (%) | 76 | 90 | 283 | 80 |
| Model 1 | 1.54 (1.20, 1.99) | 0.96 (0.75, 1.22) | ref | 1.02 (0.79, 1.30) |
| Model 2 | 1.19 (0.92, 1.54) | 0.82 (0.64, 1.04) | ref | 0.96 (0.75, 1.23) |
| Model 3 | 1.12 (0.86, 1.46) | 0.80 (0.63, 1.02) | ref | 0.92 (0.72, 1.19) |
| Black | ||||
| All-cause mortality | ||||
| No. of death (%) | 962 | 1294 | 2888 | 1384 |
| Model 1 | 1.16 (1.08, 1.25) | 1.03 (0.96, 1.10) | ref | 1.12 (1.05, 1.20) |
| Model 2 | 1.09 (1.01, 1.17) | 1.02 (0.96, 1.09) | ref | 1.09 (1.02, 1.16) |
| Model 3 | 1.06 (0.98, 1.14) | 1.00 (0.93, 1.07) | ref | 1.06 (0.99, 1.13) |
| CVD mortality | ||||
| No. of death (%) | 296 | 426 | 903 | 398 |
| Model 1 | 1.15 (1.01, 1.31) | 1.09 (0.97, 1.22) | ref | 1.04 (0.92, 1.17) |
| Model 2 | 1.08 (0.95, 1.24) | 1.08 (0.96, 1.21) | ref | 1.01 (0.90, 1.13) |
| Model 3 | 1.06 (0.93, 1.21) | 1.06 (0.95, 1.19) | ref | 1.00 (0.89, 1.12) |
| Cancer mortality | ||||
| No. of death (%) | 241 | 346 | 794 | 348 |
| Model 1 | 1.07 (0.93, 1.24) | 1.01 (0.89, 1.14) | ref | 1.04 (0.92, 1.18) |
| Model 2 | 1.02 (0.88, 1.18) | 1.00 (0.88, 1.14) | ref | 1.01 (0.89, 1.15) |
| Model 3 | 0.99 (0.86, 1.15) | 0.97 (0.85, 1.10) | ref | 0.98 (0.87, 1.12) |
Model 1: adjusted for age (continuous) and sex (male, female).
Model 2: adjusted for variables in Model 1 and education (less than high school, high school, vocational training or some college, college or higher), household income (<$15,000, $15,000-<$25,000, $25,000-<$50,000, ≥$50,000), marital status (Married, separated, divorced or widowed, never married), and employment status (yes, no). P-for-interaction between sleep duration categories and race: 0.04 for all-cause mortality, 0.03 for CVD mortality, and 0.19 for cancer mortality.
Model 3: adjusted for variables in Model 2 and smoking (current, former, never), alcohol (zero, more than zero but less than one, one or more drinks per day), total physical activity (quartiles), total sitting time (quartiles), BMI (<18.5, 18.5-<25.0, 25.0-<30.0, 30.0-<35.0, 35.0-<40.0, ≥40.0, kg/m2), and history of diabetes (yes, no), hypertension (yes, no), hypercholesterolemia (yes, no) and depression (yes, no).
Abbreviations: BMI, body mass index; CI, confidence interval; CVD, cardiovascular disease; HR, hazard ratio