TABLE 1.
Baseline characteristics of participants according to probable insomnia status in 2004 in the HPFS1
| Insomnia |
|||
| No | Yes | P | |
| Participants, n | 11,457 | 3816 | — |
| Age, y | 67.6 ± 7.82 | 67.0 ± 8.1 | <0.001 |
| BMI, kg/m2 | 25.5 ± 4.3 | 25.8 ± 4.4 | <0.001 |
| Caucasian, % | 97.0 | 96.2 | 0.02 |
| Marriage status (married), % | 89.4 | 87.6 | 0.001 |
| Living alone, % | 7.7 | 9.4 | <0.001 |
| Past smoker, % | 49.7 | 51.3 | 0.13 |
| Current smoker, % | 3.3 | 3.1 | 0.40 |
| Alcohol, g/d | 14.1 ± 16.8 | 12.7 ± 15.7 | <0.001 |
| Physical activity, MET-h/wk | 50.8 ± 48.7 | 42.1 ± 42.1 | <0.001 |
| Alternate Healthy Eating Index | 52.2 ± 11.4 | 51.4 ± 11.4 | <0.001 |
| Total calories, kcal/d | 2049.0 ± 617.3 | 2049.0 ± 631.4 | 0.98 |
| Use of aspirin, % | 58.3 | 58.6 | 0.96 |
| Sleep duration, h/d | 7.1 ± 1.0 | 6.9 ± 1.0 | <0.001 |
| Frequent snoring, % | 33.2 | 37.9 | <0.001 |
| Depression symptom,3 % | 6.3 | 17.5 | <0.001 |
| Elevated cholesterol, % | 55.4 | 60.2 | <0.001 |
| Elevated triglycerides, % | 36.9 | 42.2 | <0.001 |
| High blood pressure,4 % | 47.2 | 53.6 | <0.001 |
| Caffeine, mg/d | 153.4 ± 152.5 | 155.3 ± 151.0 | 0.57 |
1
Values were standardized to the age distribution of the study population except for age. HPFS, Health Professionals Follow-Up Study; MET-h, metabolic equivalent task hours from recreational and leisure-time activities.
2
Mean ± SD (all such values).
3
Defined as the use of antidepressant medications or an affirmative answer to the question “feel blue, sad or depressed?”
4
Considered as either a physician diagnosis of hypertension or use of an antihypertensive medication.