Table 1a.
Characteristics of older men in the MrOS cohort by quintiles of pseudo F-statistic (rest-activity rhythm robustness)
| Characteristic | Quintile 1 (<640.3; n=600) | Quintile 2 (640.3 – <853.5; n=600) | Quintile 3 (853.5– <1092.8; n=600) | Quintile 4 (1092.8 – <1415.1; n=600) | Quintile 5 (≥ 1415.1; n=601) | p-value |
|---|---|---|---|---|---|---|
| Age (years), mean ± SD | 77.7 ± 5.8 | 77.0 ± 5.7 | 76.1 ± 5.3 | 75.9 ± 5.3 | 75.0 ± 5.0 | <0.001 |
| Non-white race, n (%) | 77 (12.8) | 59 (9.8) | 58 (9.7) | 58 (9.7) | 51 (8.5) | 0.138 |
| BMI (kg/m2), mean ± SD | 28.3 ± 4.4 | 27.5 ± 4.0 | 27.1 ± 3.7 | 26.8 ± 3.4 | 26.4 ± 3.3 | <0.001 |
| Smoking status, n (%) | 0.188 | |||||
| Never | 217 (36.2) | 252 (42) | 236 (39.3) | 251 (41.8) | 223 (37.1) | |
| Past | 364 (60.8) | 340 (56.7) | 354 (59) | 339 (56.5) | 366 (60.9) | |
| Current | 18 (3.0) | 8 (1.3) | 10 (1.7) | 10 (1.7) | 12 (2) | |
| Alcohol intake (drinks/week), n (%) | <0.001 | |||||
| < 1 | 318 (53.4) | 318 (53.2) | 275 (46.1) | 261 (43.6) | 231 (38.7) | |
| 1–13 (moderate) | 251 (42.1) | 256 (42.8) | 286 (47.9) | 307 (51.3) | 314 (52.6) | |
| ≥ 14 (heavy) | 27 (4.5) | 24 (4.0) | 36 (6.0) | 31 (5.2) | 52 (8.7) | |
| History of diabetes mellitus, n (%) | 108 (18.0) | 82 (13.7) | 80 (13.3) | 60 (10) | 71 (11.8) | 0.001 |
| History or coronary heart disease,* n (%) | 272 (45.6) | 198 (33) | 190 (31.7) | 177 (29.6) | 157 (26.2) | <0.001 |
| History of hypertension, n (%) | 346 (57.8) | 309 (51.5) | 313 (52.2) | 288 (48) | 242 (40.3) | <0.001 |
| History of stroke, n (%) | 31 (5.2) | 29 (4.8) | 15 (2.5) | 19 (3.2) | 16 (2.7) | 0.031 |
| Caffeine intake (mg/d), mean ± SD | 220.4 ± 256.4 | 227.0 ± 254.3 | 225.6 ± 227.4 | 246.3 ± 242.5 | 259.6 ± 250.7 | 0.002 |
| Actigraphic mean daytime activity level (counts),** mean ± SD | 2815.8 ± 596.4 | 3308.6 ± 524.1 | 3545.9 ± 519.7 | 3915.9 ± 539.8 | 4337.1 ± 549.3 | <0.001 |
| Depression (GDS ≥ 6), n (%) | 70 (11.7) | 48 (8.0) | 30 (5.0) | 22 (3.7) | 26 (4.3) | <0.001 |
| Benzodiazepine use, n (%) | 40 (6.7) | 25 (4.2) | 24 (4) | 17 (2.8) | 28 (4.7) | 0.026 |
| Antidepressant use, n (%) | 69 (11.5) | 39 (6.5) | 55 (9.2) | 32 (5.3) | 40 (6.7) | <0.001 |
| Use of prescription sleep medication, n (%) | 18 (3) | 10 (1.7) | 9 (1.5) | 11 (1.8) | 12 (2) | 0.374 |
| Femoral neck BMD (g/cm2), mean ± SD | 0.8 ± 0.1 | 0.8 ± 0.1 | 0.8 ± 0.1 | 0.8 ± 0.1 | 0.8 ± 0.1 | 0.617 |
| Femoral neck BMD T-score, mean ± SD | −0.60 ± 1.11 | −0.66 ± 1.12 | −0.60 ± 1.13 | −0.66 ± 1.04 | −0.67 ± 1.01 | 0.617 |
| Femoral neck T-score Category, n (%) | 0.382 | |||||
| ≥−1 (Normal) | 365 (62) | 359 (60) | 375 (63) | 346 (58) | 356 (60) | |
| −1< T-score <−2.5 (Osteopenic) | 206 (35) | 219 (37) | 203 (34) | 239 (40) | 228 (38) | |
| ≤−2.5 (Osteoporotic) | 19 (3.2) | 16 (2.7) | 16 (2.7) | 10 (1.7) | 13 (2.2) | |
| ≥ 1 IADL impairments, n (%) | 226 (37.7) | 131 (21.8) | 107 (17.8) | 86 (14.3) | 81 (13.5) | <0.001 |
| Nocturia (≥ 3 times/week), n (%) | 454 (75.8) | 460 (76.7) | 450 (75) | 433 (72.2) | 428 (71.2) | 0.137 |
| Gait speed (m/s), mean ± SD | 1.1 ± 0.2 | 1.1 ± 0.3 | 1.2 ± 0.2 | 1.2 ± 0.2 | 1.2 ± 0.2 | <0.001 |
P-values for continuous variables are from ANOVA for normally distributed data; the Kruskal Wallis test was used for skewed data. P-values for categorical data from a chi-square test.
*
Coronary heart disease defined as a history of myocardial infarction, angina, congestive heart failure, bypass surgery, angioplasty or pacemaker placement.
**
From the out-of-bed interval; the time men were not in bed trying to sleep (includes naps)