Table 1.
Sociodemographic, clinical, and psychosocial characteristics at baseline
| Clinical insomnia (N = 488) | No insomnia (N = 594) | P-value* | Total (n = 1082) | |
|---|---|---|---|---|
| Sociodemographic factors | ||||
| Age, mean (SD) | 60.2 (10) | 62.5 (9) | <0.001 | 61.5 (10) |
| Female gender, n (%) | 130 (27) | 96 (16) | <0.001 | 226 (21) |
| Low education (≤ 12 years), n (%) | 354 (74) | 396 (67) | 0.015 | 750 (70) |
| Living alone, n (%) | 104 (23) | 90 (16) | 0.005 | 194 (19) |
| Clinical factors | ||||
| Coronary index diagnosis | ||||
| Acute myocardial infarction, n (%) | 390 (80) | 468 (79) | 0.648 | 858 (79) |
| Stable or unstable angina, n (%) | 98 (20) | 126 (21) | 224 (21) | |
| More than 1 coronary event prior to the index event, n (%) | 150 (31) | 175 (30) | 0.649 | 234 (30) |
| Participation in cardiac rehabilitation, n (%) | 222 (46) | 287 (48) | 0.055 | 509 (47) |
| Coronary risk factors at interview | ||||
| CRP mg/L, mean (SD)† | 2.8 (3) | 2.3 (3) | 0.001 | 2.5 (3) |
| LDL cholesterol mmol/L, mean (SD) | 2.1 (1) | 2.1 (1) | 0.087 | 2.1 (1) |
| Current smoking, n (%) | 114 (24) | 105 (19) | 0.033 | 219 (21) |
| Diabetes, n (%) | 102 (21) | 81 (14) | 0.002 | 183 (17) |
| Low physical activity‡, n (%) | 310 (64) | 330 (56) | 0.011 | 640 (60) |
| Systolicblood pressure, mmHg mean (SD) | 137 (19) | 140 (19) | 0.017 | 138 (19) |
| Waistcircumference in 1 cm, mean (SD) | 104 (13) | 101 (12) | 0.007 | 102 (12) |
| Not taking statins (past week) n (%) | 42 (9) | 39 (7) | 0.204 | 81 (8) |
| OSA risk (yes/no), n (%) | 243 (58) | 187 (37) | <0.001 | 430(47) |
| Cardiovascular comorbidity | ||||
| Stroke/TIA, n (%) | 24 (5) | 49 (8) | 0.030 | 73 (7) |
| Peripheral artery disease, n (%) | 41 (8) | 49 (8) | 0.928 | 90 (8) |
| Kidney failure, n (%) | 62 (14) | 71 (13) | 0.645 | 133 (13) |
| Heart failure, n (%) | 52 (11) | 84 (14) | 0.085 | 136 (13) |
| Psychosocial factors | ||||
| Bergen Insomnia Scale sum, mean (SD) | 23.3 (9) | 6.4 (5) | <0.001 | 13.9 (11) |
| Taking sleep medication past week, n (%) | 115 (24) | 44 (8) | <0.001 | 159 (25) |
| HADS-A ≥ 8, n (%) | 170 (37) | 51 (9) | <0.001 | 231 (21) |
| HADS-D ≥ 8, n (%) | 113 (24) | 43 (7) | <0.001 | 156 (14) |
*p-values calculated with t-test for mean and chi-square for n.
†Excluded cases > 15 mg/L.
‡Low physical activity is defined as < physical activity for 30 min 2–3 times a week.
SD, standard deviation; CRP, C-reactive protein; LDL, low density lipoprotein; TIA, transient ischemic attack; HADS-A, hospital anxiety and depression rating scale-anxiety subscale; HADS-D, hospital anxiety and depression rating scale-depression subscale.