Table 2.
Characteristics of the SOF cohort among categories of incident clinical cognitive status.
| Characteristic | Normal N = 767 |
MCI N = 287 |
Dementia N = 178 |
P-value |
|---|---|---|---|---|
| Age, years | 82.3 ± 3.1 | 82.8 ± 3.3 | 83.7 ± 4.0 | <0.0001 |
| Median (range) | 82 (70–92) | 83 (73–91) | 83.5 (73–96) | |
| African American | 74 (9.7) | 36 (12.5) | 24 (13.5) | 0.20 |
| Education, years | 13.1 ± 2.6 | 12.4 ± 2.5 | 12.7 ± 2.6 | 0.0001 |
| Median (range) | 12 (1–19) | 12 (7–19) | 12 (5–19) | |
| BMI, kg/m2 | 27.5 ± 4.8 | 27.6 ± 4.6 | 27.2 ± 5.3 | 0.74 |
| Median (range) | 26.8 (17.4–51.7) | 27.5 (18.8–46.0) | 26.8 (17.2–45.8) | |
| Any medical history* | 436 (56.9) | 158 (55.1) | 106 (59.6) | 0.63 |
| COPD | 89 (11.6) | 36 (12.5) | 23 (12.9) | 0.84 |
| Diabetes | 69 (9.0) | 29 (10.1) | 20 (11.2) | 0.62 |
| Stroke | 66 (8.6) | 30 (10.5) | 24 (13.5) | 0.13 |
| Cardiovascular disease† | 172 (22.4) | 60 (20.9) | 42 (23.6) | 0.78 |
| Cancer | 187 (24.4) | 54 (18.8) | 38 (21.3) | 0.14 |
| Parkinson’s disease | 1 (0.1) | 1 (0.3) | 1 (0.6) | 0.53 |
| History of hypertension | 455 (59.3) | 163 (56.8) | 114 (64.0) | 0.30 |
| Depression (GDS score ≥ 6) | 46 (6.0) | 28 (9.8) | 25 (14.0) | 0.0009 |
| Current antidepressant user | 58 (7.6) | 37 (12.9) | 35 (19.7) | <0.0001 |
| Current benzodiazepine user | 51 (6.6) | 17 (5.9) | 15 (8.4) | 0.57 |
| Current sleep medication user | 9 (1.2) | 1 (0.3) | 4 (2.2) | 0.17 |
| Current smoker | 14 (1.8) | 10 (3.5) | 3 (1.7) | 0.23 |
| Alcohol consumption, drinks/week | 1.2 ± 3.1 | 1.2 ± 2.8 | 0.5 ± 1.4 | <0.0001 |
| Median (range) | 0 (0–42) | 0 (0–17.5) | 0 (0–7) | |
| Caffeine intake, mg/day | 159.9 ± 156.5 | 158.0 ± 157.6 | 137.6 ± 143.5 | 0.23 |
| Median (range) | 140 (0–950) | 110 (0–815) | 95 (0–760) | |
| Walks for exercise | 330 (43.5) | 119 (41.8) | 61 (34.9) | 0.11 |
| IADL impairments (of 6) | 1.0 ± 1.5 | 1.2 ± 1.6 | 1.6 ± 1.8 | <0.0001 |
| Median (range) | 0 (0–6) | 0 (0–6) | 1 (0–6) | |
| Self-reported health status, fair/poor/very poor | 136 (17.7) | 61 (21.3) | 41 (23.0) | 0.17 |
| MMSE score (0–30) | 28.7 ± 1.2 | 28.3 ± 1.4 | 27.7 ± 1.5 | <0.0001 |
| Median (range) | 29 (24–30) | 29 (24–30) | 28 (24–30) | |
| Trails B time to complete, seconds | 123.9 ± 53.9 | 157.2 ± 69.6 | 164.0 ± 76.9 | <0.0001 |
| Median (range) | 111 (46–421) | 138 (55–421) | 145.5 (66 – 421) | |
| Actigraphic sleep efficiency, % | 79.6 ± 10.6 | 78.5 ± 11.3 | 78.0 ± 10.5 | 0.10 |
| Median (range) | 82.2 (30.5–96.8) | 81.7 (9.8–95.2) | 80.4 (34.8–97.1) | |
| Actigraphic total sleep time, minutes | 407.7 ± 69.4 | 407.0 ± 70.7 | 410.0 ± 67.2 | 0.90 |
| Median (range) | 414.5 (142.7–618.8) | 415 (59.8–564.8) | 415 (199–576.5) | |
| Time wearing actigraph, days | 3.6 ± 0.6 | 3.6 ± 0.6 | 3.5 ± 0.7 | 0.17 |
| Median (range) | 3.5 (2.3–7.3) | 3.5 (2.3–6.6) | 3.4 (2.3–6.4) |
SOF, Study of Osteoporotic Fractures; MCI, mild cognitive impairment; BMI, body mass index; COPD, chronic obstructive pulmonary disease; GDS, Geriatric Depression Scale; IADL, instrumental activities of daily living; MMSE, Mini-Mental State Examination; SD, standard deviation.
All continuous data are mean ± SD; P-values are from an ANOVA if normally distributed or Kruskal-Wallis test if skewed. All categorical data are N (%); P-values are from a χ2 test for homogeneity.
*Any medical history indicates prior physician diagnosis of one or more of the following: COPD, diabetes, stroke, cardiovascular disease, cancer, or Parkinson’s disease.
†Cardiovascular disease includes myocardial infarction, angina, congestive heart failure, or other heart disease.