Table 1.
Baseline Characteristics of the Sample (N = 805) and Stratified by Sex in the Study of Muscle, Mobility and Aging (SOMMA)*
| Characteristics | All (N = 805) | Women (n = 469) | Men (n = 336) | p Value |
|---|---|---|---|---|
| PPFI score | 1.38 [0, 2.89] | 1.72 [0, 2.97] | 0.82 [0, 2.80] | <.001 |
| Age, years | 76.4 ± 5.0 | 76.4 ± 5.0 | 76.3 ± 5.1 | .60 |
| Race, White | 687 (85.3) | 389 (82.9) | 298 (88.7) | .02 |
| Height, cm | 166.0 ± 9.8 | 159.8 ± 6.3 | 174.6 ± 6.9 | <.001 |
| Weight, kg | 76.3 ± 15.3 | 70.1 ± 13.2 | 84.9 ± 13.8 | <.001 |
| BMI, kg/m2 | 27.6 ± 4.6 | 27.5 ± 4.9 | 27.9 ± 4.2 | .20 |
| Smoking status | .67 | |||
| Current smoker | 25 (3.1) | 16 (3.4) | 9 (2.7) | |
| Former smoker | 331 (41.4) | 188 (40.3) | 143 (42.9) | |
| Never smoker | 444 (55.5) | 263 (56.3) | 181 (54.4) | |
| 400 m gait speed, m/s | 1.05 ± 0.18 | 1.02 ± 0.17 | 1.08 ± 0.17 | <.001 |
| SPPB score, 0–12 | 10.2 ± 1.7 | 10.1 ± 1.7 | 10.3 ± 1.8 | .19 |
| Chair stand speed, stands per second | 0.4 ± 0.1 | 0.4 ± 0.1 | 0.4 ± 0.1 | .33 |
| Leg peak power, watts/kg | 4.7 ± 1.7 | 3.9 ± 1.2 | 5.7 ± 1.8 | <.001 |
| VO2peak, mL/kg/min | 20.2 ± 4.9 | 18.7 ± 4.1 | 22.3 ± 5.0 | <.001 |
| PFS Physical score, 0–50 | 15.7 ± 8.6 | 16.8 ± 8.4 | 14.2 ± 8.6 | <.001 |
| RPE fatigability, 6–20 | 8.4 ± 1.9 | 8.5 ± 1.9 | 8.2 ± 1.7 | .01 |
| Hypertension† | 416 (51.7) | 237 (50.5) | 179 (53.3) | .44 |
| Diabetes‡ | 125 (15.6) | 64 (13.7) | 61 (18.3) | .08 |
| Heart diseases‡ | 56 (7.0) | 24 (5.1) | 32 (9.6) | .02 |
| Stroke‡ | 21 (2.6) | 10 (2.1) | 11 (3.3) | .31 |
| Lung disease‡ | 106 (13.2) | 69 (14.7) | 37 (11.1) | .13 |
| Osteoporosis‡ | 140 (17.5) | 129 (27.6) | 11 (3.3) | <.001 |
| Arthritis‡ | 448 (55.9) | 304 (65.1) | 144 (43.1) | <.001 |
| Fall history§ | 223 (27.8) | 142 (30.3) | 81 (24.3) | .06 |
| CES-D, 0–30 | 4.1 ± 3.5 | 4.4 ± 3.5 | 3.7 ± 3.52 | .006 |
Notes: All reported in median (25th percentile, 75th percentile), mean ± SD or n (%). BMI = body mass index; CES-D = Center for Epidemiologic Studies—Depression Scale; PFS = Pittsburgh Fatigability Scale; PPFI = Pittsburgh Performance Fatigability Index; RPE = Borg Rating of Perceived Exertion; SPPB = Short Physical Performance Battery.
*There were n = 1 participant missing SPPB score and chair stand speed, n = 34 participants missing leg peak power, n = 51 missing VO2peak, n = 6 missing PFS Physical score, n = 34 missing RPE fatigability, n = 5 participants missing smoking status.
†Hypertension was classified by systolic blood pressure ≥130 mmHg or diastolic blood pressure ≥80 mmHg.
‡Diabetes and all following health conditions were self-report of physician diagnoses. Heart disease included heart attack or myocardial infarction, heart failure, or atrial fibrillation. Lung diseases included chronic obstructive lung disease, chronic bronchitis, asthma, emphysema, and chronic obstructive pulmonary disease .
§Fall history was self-reported and asked as “During the past 12 months, have you fallen and landed on the floor or ground, or fallen and hit an object like a table or chair?”.