Table 1.
Baseline Characteristics by Hours of Sleep Excluding Those With No Following or Missing Exposure or Falls Data
| Hours of sleep | |||||||
|---|---|---|---|---|---|---|---|
| 5 or less | 6 | 7 | 8 | 9 | 10 or more | p (test of trend) | |
| n (%) | 13,119 (8.3) | 43,306 (27.5) | 58,962 (37.4) | 35,029 (22.2) | 6,080 (3.9) | 810 (0.5) | |
| Age (years), mean ± SD | 63.2 (7.6) | 63.1 (7.4) | 63.0 (7.2) | 63.5 (7.0) | 64.0 (7.1) | 63.2 (7.4) | <0.001 |
| Race/ethnicity, n (%) | <0.001 | ||||||
| American Indian or Alaskan Native | 107 (0.8) | 190 (0.4) | 209 (0.4) | 140 (0.4) | 26 (0.4) | 4 (0.5) | |
| Asian or Pacific Islander | 628 (4.8) | 1,614 (3.7) | 1,305 (2.2) | 464 (1.3) | 69 (1.1) | 10 (1.2) | |
| Black or African‐American | 2,580 (19.7) | 5,086 (11.8) | 3,754 (6.4) | 1,849 (5.3) | 410 (6.8) | 152 (18.8) | |
| Hispanic/Latino | 794 (6.1) | 1,806 (4.2) | 1,944 (3.3) | 1,105 (3.2) | 206 (3.4) | 107 (13.2) | |
| White (not of Hispanic origin) | 8,735 (66.8) | 33,925 (78.5) | 51,042 (86.8) | 31,047 (88.9) | 5,303 (87.4) | 531 (65.6) | |
| Other | 239 (1.8) | 573 (1.3) | 573 (1.0) | 331 (0.9) | 53 (0.9) | 5 (0.6) | |
| Education, n (%) | <0.001 | ||||||
| High school or less | 3,847 (29.6) | 10,038 (23.4) | 11,986 (20.5) | 7,383 (21.2) | 1,381 (22.9) | 262 (32.7) | |
| Some college or vocational training | 5,426 (41.7) | 16,792 (39.1) | 21,655 (37.0) | 12,882 (37.0) | 2,289 (37.9) | 292 (36.4) | |
| College grad or more | 3,725 (28.7) | 16,129 (37.5) | 24,927 (42.6) | 14,525 (41.8) | 2,372 (39.3) | 248 (30.9) | |
| Missing | 2,314 (17.6) | 7,991 (18.5) | 10,842 (18.4) | 6,268 (17.9) | 1,047 (17.2) | 133 (16.4) | |
| Physical activity (MET hours/week), n (%) | <0.001 | ||||||
| ≤2.5 | 4,034 (32.0) | 11,201 (27.0) | 13,240 (23.6) | 7,861 (23.5) | 1,577 (27.2) | 263 (34.1) | |
| 2.5 to <5 | 1,594 (12.7) | 4,836 (11.7) | 6,104 (10.9) | 3,748 (11.2) | 666 (11.5) | 100 (13.0) | |
| 5 to <12 | 2,865 (22.8) | 9,778 (23.6) | 13,734 (24.4) | 7,949 (23.8) | 1,355 (23.4) | 171 (22.2) | |
| ≥12 | 4,095 (32.5) | 15,676 (37.8) | 23,128 (41.1) | 13,847 (41.5) | 2,190 (37.8) | 238 (30.8) | |
| Alcohol intake, n (%) | <0.001 | ||||||
| ≤2 drinks/day | 12,746 (97.4) | 41,829 (96.8) | 56,586 (96.3) | 33,203 (95.1) | 5,641 (93.2) | 756 (93.8) | |
| >2 drinks/day | 338 (2.6) | 1,365 (3.2) | 2,191 (3.7) | 1,725 (4.9) | 414 (6.8) | 50 (6.2) | |
| Smoking status, n (%) | <0.001 | ||||||
| Never smoked | 6,758 (52.1) | 21,768 (50.9) | 29,890 (51.3) | 17,533 (50.6) | 2,896 (48.2) | 367 (45.9) | |
| Past smoker | 5,063 (39.1) | 17,788 (41.6) | 24,604 (42.2) | 14,969 (43.2) | 2,702 (45.0) | 351 (43.9) | |
| Current smoker | 1,138 (8.8) | 3,245 (7.6) | 3,802 (6.5) | 2,122 (6.1) | 409 (6.8) | 81 (10.1) | |
| Hormone therapy, n (%) | <0.001 | ||||||
| Never used | 6,415 (49.0) | 19,399 (44.8) | 24,907 (42.3) | 14,775 (42.2) | 2,632 (43.3) | 404 (49.9) | |
| Past user | 2,362 (18.0) | 7,072 (16.3) | 9,099 (15.4) | 5,527 (15.8) | 1,002 (16.5) | 123 (15.2) | |
| Current user | 4,326 (33.0) | 16,795 (38.8) | 24,907 (42.3) | 14,706 (42.0) | 2,439 (40.2) | 282 (34.9) | |
| Depressive symptoms (CESD >0.06), n (%) | <0.001 | ||||||
| No | 9,514 (75.0) | 36,628 (86.6) | 53,040 (91.8) | 31,901 (92.8) | 5,298 (89.4) | 597 (76.1) | |
| Yes | 3,173 (25.0) | 5,644 (13.4) | 4,768 (8.2) | 2,461 (7.2) | 625 (10.6) | 188 (23.9) | |
| Dietary caffeine (mg/day), mean ± SD | 150.6 (140.8) | 164.7 (137.3) | 169.7 (133.4) | 168.6 (131.2) | 166.9 (137.1) | 146.6 (142.3) | <0.001 |
| Total calcium (mg/day), mean ± SD | 1059 (705) | 1137 (710) | 1200 (708) | 1201 (705) | 1195 (725) | 1108 (752) | <0.001 |
| Antidepressants (yes), n (%) | 922 (7.0) | 2,675 (6.2) | 3,710 (6.3) | 2,820 (8.1) | 836 (13.8) | 172 (21.2) | <0.001 |
| Anti‐anxiety pills (yes), n (%) | 607 (4.6) | 1,481 (3.4) | 1,645 (2.8) | 1,003 (2.9) | 237 (3.9) | 34 (4.2) | <0.001 |
| Hypnotics (yes), n (%) | 576 (4.4) | 1,449 (3.3) | 1,435 (2.4) | 757 (2.2) | 146 (2.4) | 22 (2.7) | <0.001 |
| Analgesic narcotics (yes), n (%) | 517 (3.9) | 878 (2.0) | 957 (1.6) | 582 (1.7) | 150 (2.5) | 33 (4.1) | <0.001 |
| Oral glucocorticosteroid (yes), n (%) | 140 (1.1) | 326 (0.8) | 332 (0.6) | 225 (0.6) | 45 (0.7) | 8 (1.0) | <0.001 |
| Fracture (age ≥55 years), (yes), n (%) | 1,705 (17.4) | 5,488 (16.7) | 7,140 (15.9) | 4,415 (16.2) | 843 (17.7) | 96 (15.9) | <0.001 |
| Parental history of broken bone (age >40 years) (yes), n (%) | 4,397 (37.7) | 15,630 (39.4) | 22,280 (40.6) | 13,028 (39.8) | 2,225 (39.5) | 242 (33.4) | <0.001 |
| Parental history of broken hip (yes), n (%) | 1,488 (12.7) | 5,429 (13.7) | 7,726 (14.1) | 4,715 (14.4) | 805 (14.3) | 85 (11.7) | <0.001 |
| Weight (kg), mean ± SD | 75.8 (18.6) | 73.9 (17.2) | 72.7 (16.4) | 73.3 (16.4) | 74.6 (17.2) | 77.8 (19.3) | <0.001 |
| Height (cm), mean ± SD | 160.7 (6.8) | 161.4 (6.7) | 162.0 (6.6) | 162.2 (6.6) | 162.4 (6.4) | 161.2 (7.1) | <0.001 |
| Diabetes treated (pills or shots) (yes), n (%) | 976 (7.4) | 2,039 (4.7) | 2,174 (3.7) | 1,290 (3.7) | 299 (4.9) | 57 (7.0) | <0.001 |
| In general, health is fair/poor, n (%) | 2586 (19.8) | 4305 (9.9) | 3950 (6.7) | 3798 (6.8) | 633 (10.3) | 203 (25.3) | <0.001 |
| Times fell down last 12 months, n (%) | <0.001 | ||||||
| None | 8,124 (64.3) | 27,647 (66.3) | 38,506 (68.1) | 23,247 (69.2) | 3,931 (67.5) | 511 (66.0) | |
| 1 | 2,413 (19.1) | 8,462 (20.3) | 11,519 (20.4) | 6,661 (19.8) | 1,130 (19.4) | 124 (16.0) | |
| 2 | 1,258 (10.0) | 3,778 (9.1) | 4,427 (7.8) | 2,462 (7.3) | 503 (8.6) | 80 (10.3) | |
| ≥3 | 843 (6.7) | 1,812 (4.3) | 2,052 (3.6) | 1,240 (3.7) | 261 (4.5) | 59 (7.6) | |
| Physical function score, mean ± SD a | 73.9 (24.1) | 80.4 (20.3) | 83.1 (18.4) | 82.3 (19.1) | 78.4 (21.7) | 69.5 (25.8) | <0.001 |
a
Rand‐36 physical function score (34).