TABLE 1.
Baseline participant characteristics
| Overall sample (n = 380) | Subset with repeated mobility (n = 279) | |||||
|---|---|---|---|---|---|---|
| Mean (SD) or N (%) | Range | Correlations with kPCr, p‐value | Mean (SD) or N (%) | Range | Correlations with kPCr, p‐value | |
| Demographics | ||||||
| Age, years | 72.9 (7.8) | 60–91 | <0.001 | 73.9 (7.7) | 60–91 | 0.022 |
| Women | 203 (53) | – | <0.001 | 149 (53) | – | <0.001 |
| Blacks | 83 (22) | – | <0.001 | 53 (19) | – | <0.001 |
| Height, cm | 168 (9) | 147–192 | 0.380 | 168 (9) | 148–192 | 0.931 |
| Body mass index, kg/m2 | 26.7 (4.2) | 17–43 | 0.047 | 26.3 (4.1) | 17–38 | 0.020 |
| kPCr, s−1 | 0.0207 (0.0049) | 0.0114–0.0404 | – | 0.0202 (0.0046) | 0.0114–0.0404 | – |
| PCr depletion, % | 55 (11) | 33–91 | 0.727 | 55 (11) | 33–91 | 0.302 |
| Muscle strength, N·m | 111 (38) (n = 334) | 34–248 (n = 334) | 0.015 (n = 334) | 108 (37) (n = 245) | 34–244 (n = 245) | 0.085 (n = 245) |
| Total fat mass, kg | 26 (9.6) (n = 365) | 5.3–65 (n = 365) | 0.006 (n = 365) | 25.3 (9.3) (n = 273) | 5.3–55 (n = 273) | 0.002 (n = 273) |
| Total lean mass, kg | 46 (9.6) (n = 365) | 31–72 (n = 365) | 0.352 (n = 365) | 46 (9.7) (n = 273) | 31–71 (n = 273) | 0.745 (n = 273) |
| Mobility assessment | ||||||
| 6‐m usual gait speed, m/s | 1.26 (0.17) | 1.00–1.81 | <0.001 | 1.25 (0.16) | 1.00–1.81 | <0.001 |
| 2.5‐min usual gait speed, m/s | 1.26 (0.14) | 0.88–1.64 | <0.001 | 1.26 (0.13) | 0.93–1.61 | <0.001 |
| 6‐m rapid gait speed, m/s | 1.88 (0.30) | 1.32–3.21 | 0.002 | 1.87 (0.31) | 1.32–3.21 | 0.049 |
| 400‐m walk time, sec | 265 (38) (n = 374) | 162–418 (n = 374) | <0.001 (n = 374) | 265 (36) (n = 267) | 162–419 (n = 267) | <0.001 (n = 267) |
| Follow‐up time, years | 2.5 (1.8) | 0–6 | – | 3.5 (1.2) | 1–6 | – |
| Number of visits per participant | 2.4 (1.2) | 1–7 | – | 2.9 (1.0) | 2–7 | – |
p‐Values were based on Pearson's coefficient for continuous variables and independent t tests for binary variables. Bold numbers reflect significant correlations at two‐sided p < 0.05.