Table 1.
Baseline characteristics by category of GDS score
| Characteristic | Overall (n=2,464) | GDS <6 (n=2,328) | GDS ≥6 (n=136) | p value |
|---|---|---|---|---|
| Age, years, mean (SD) | 75.7 (5.2) | 75.7 (5.1) | 76.7 (5.8) | 0.03 |
| Race, n (%) | 0.08 | |||
| White | 2,222 (90.2) | 2,106 (90.5) | 116 (85.3) | |
| Black | 89 (3.6) | 79 (3.4) | 10 (7.4) | |
| Asian | 78 (3.2) | 74 (3.2) | 4 (2.9) | |
| Hispanic/Other | 75 (3.0) | 69 (3.0) | 6 (4.4) | |
| BMI, kg/m2, mean (SD) | 27.2 (3.7) | 27.1 (3.7) | 27.5 (4.2) | 0.38 |
| Weight change from sleep visit to follow-up visit, kg, mean (SD) | −1.15 (4.45) | −1.12 (4.38) | −1.66 (5.58) | 0.27 |
| Hip BMD, mean (SD) | 0.96 (0.14) | 0.96 (0.14) | 0.93 (0.16) | 0.05 |
| Self-reported health, n (%) | <0.001 | |||
| Excellent/good | 2,174 (88.3) | 2,097 (90.1) | 77 (56.6) | |
| Fair/poor/very poor | 289 (11.8) | 230 (9.9) | 59 (43.4) | |
| No. of IADLs, range 0–5, mean (SD) | 0.27 (0.69) | 0.23 (0.63) | 0.89 (1.18) | <0.001 |
| 5 chair stand, s, mean (SD) | 11.4 (3.4) | 11.4 (3.3) | 12.9 (4.3) | <0.001 |
| Walking speed, (m/s), mean (SD) | 1.17 (0.22) | 1.18 (0.21) | 1.01 (0.25) | <0.001 |
| Falls within previous 12 months, n (%) | 700 (28.4) | 634 (27.2) | 66 (48.6) | <0.001 |
| Current smoker, n (%) | 53 (2.2) | 45 (1.9) | 8 (5.9) | 0.01 |
| Calcium use, n (%) | 798 (32.4) | 761 (32.7) | 37 (27.4) | 0.20 |
| MMSE, range 0–100, mean (SD) | 93.5 (5.1) | 93.6 (4.9) | 91.4 (7.4) | 0.001 |
| ≥1 comorbidities, n (%) | 942 (38.2) | 864 (37.1) | 78 (57.4) | <0.001 |
| Alcohol use (drinks/week) | ||||
| 0–2 | 1,424 (58.1) | 1,328 (57.3) | 96 (70.6) | 0.008 |
| 2–13 | 886 (36.1) | 850 (36.7) | 36 (26.5) | |
| 14+ | 142 (5.8) | 138 (6.0) | 4 (2.9) | |
| Thiazide use, n (%) | 459 (18.6) | 433 (18.6) | 26 (19.3) | 0.85 |
| Vitamin D use, n (%) | 1,567 (63.6) | 1,495 (64.2) | 72 (53.3) | 0.01 |
| Bisphosphonate use, n (%) | 110 (4.5) | 102 (4.4) | 8 (5.9) | 0.40 |
| Antidepressant use, n (%) | 170 (6.9) | 137 (5.9) | 33 (24.4) | <0.001 |
| Oral corticosteroid use, n (%) | 35 (1.4) | 30 (1.3) | 5 (3.7) | 0.04 |
| PASE score, mean (SD) | 151.2 (70.4) | 153.2 (70.3) | 116.5 (64.0) | <0.001 |
p values for continuous variables are from t test, except for IADL and m-MMSE which are from Wilcoxon rank sum tests due to skewness; p values for categorical data are from chi-squared tests, except oral corticosteroid use, smoking status and race which are from Fisher’s exact test due to small expected cell counts
BMI body mass index, BMD bone mineral density, IADLs instrumental activities of daily living, MMSE mini mental state exam, PASE physical activity scale for the elderly