Table 3.
Hazard ratios and 95% CIs for wake-up time associated with MI on weekday.
| Total | >8:00AM | 7:01AM to 8:00AM | 6:01AM to 7:00AM | ≤6:00AM | |
|---|---|---|---|---|---|
| No. of subjects, n | 4,576 | 221 | 602 | 1,415 | 2,338 |
| Person-years | 48,454.8 | 2,022.1 | 6,042.9 | 15,058.1 | 25,331.7 |
| Events, n (%) | 294 (6.4) | 20 (9.0) | 50 (8.3) | 95 (6.7) | 129 (5.5) |
| Morbidity rate§ | 6.1 | 9.9 | 8.3 | 6.3 | 5.1 |
| Hazard ratio for weekday bedtime | |||||
| Univariate models | 1.953 (1.219–3.128) # | 1.618 (1.167–2.242) # | 1.235 (0.947–1.610) | 1(Ref) | |
| Age and sex adjusted | 1.657 (1.031–2.662) * | 1.356 (0.974–1.887) | 1.112 (0.852–1.453) | 1(Ref) | |
| Multivariable adjusteda | 1.520 (0.944–2.446) | 1.384 (0.994–1.928) | 1.133 (0.867–1.480) | 1(Ref) | |
| Multivariable adjustedb | 1.553 (0.934–2.582) | 1.418 (0.991–2.028) | 1.162 (0.883–1.530) | 1(Ref) |
MI, myocardial infarction; 95% CI, 95% confidence interval.
§
Crude event rate per 1,000-person years.
*
P < 0.05;
#
P < 0.01.
a
adjusted for age, sex, race, BMI, smoking status, alcohol use, hypertension, diabetes mellitus, AHI.
b
adjusted by a+ self-reported sleep duration.