Table 1.
Baseline characteristics.
| Sufficient Sleep (Sleep Duration ≥ 6 h/night, SSI ≥ 0.8) (n = 4,872) | Insufficient Sleep (Sleep Duration ≥ 6 h/night, SSI < 0.8) (n = 1,079) | Short Sleep (Sleep Duration < 6 h/night, any SSI) (n = 839) | |
|---|---|---|---|
| Age, y | 43 (29 – 57) | 37 (27 – 50) | 53 (39 – 67) |
| BMI, kg/m2 | 24.0 ± 4.0 | 24.0 ± 4.1 | 24.9 ± 4.6 |
| Never smokers | 3,017 (62.3%) | 607 (56.7%) | 466 (56.1%) |
| Former smokers | 1,077 (22.2%) | 243 (22.7%) | 202 (24.3%) |
| Current smokers | 748 (15.5%) | 220 (20.6%) | 162 (19.5%) |
| Alcohol dependence | 262 (5.6%) | 83 (8.0%) | 42 (5.5%) |
| No coffee intake | 226 (4.7%) | 55 (5.1%) | 29 (3.5%) |
| 1–2 cups a day | 1,355 (28.1%) | 300 (28.0%) | 218 (26.3%) |
| 3 or more cups a day | 3,241 (67.2%) | 715 (66.8%) | 581 (70.2%) |
| Low physical activity | 792 (16.4%) | 237 (22.2%) | 211 (25.7%) |
| Moderate physical activity | 3,003 (62.2%) | 632 (59.2%) | 503 (61.3%) |
| High physical activity | 1,032 (21.4%) | 199 (18.6%) | 106 (12.9%) |
| No depression | 4,233 (90.1%) | 822 (79.2%) | 579 (73.0%) |
| Possible depression | 339 (7.2%) | 146 (14.1%) | 143 (18.0%) |
| Probable depression | 125 (2.7%) | 70 (6.7%) | 71 (9.0%) |
| No anxiety | 3,465 (73.4%) | 554 (52.6%) | 413 (51.5%) |
| Possible anxiety | 797 (16.9%) | 264 (25.1%) | 178 (22.2%) |
| Probable anxiety | 456 (9.7%) | 235 (22.3%) | 211 (26.3%) |
| Snoring | 1,158 (24.4%) | 285 (26.8%) | 234 (29.5%) |
| Daytime sleepiness | 384 (8.0%) | 288 (27.1%) | 255 (31.3%) |
Data are presented as the median and interquartile range for non–normally distributed continuous variables, the mean and standard deviation for normally distributed continuous variables, and n (%) for categorical variables. Sufficient sleep is defined as sleeping ≥ 6 hours/night and having an SSI of ≥ 0.8. Insufficient sleep is defined as sleeping ≥ 6 hours/night but having an SSI of < 0.8. Short sleep is defined as sleeping < 6 hours/night. BMI = body mass index, SSI = sleep sufficiency index.