Table 1.
Characteristics (Mean ± SD) or N (%) of Older Men by Quartile of D3Cr Muscle Mass (n = 903)
| Characteristic | Quartile 1† (lowest) | Quartile 2‡ | Quartile 3§ | Quartile 4|| (highest) | p-value |
|---|---|---|---|---|---|
| Age (y) | 86.8 ± 4.2 | 84.6 ± 3.8 | 83.2 ± 3.3 | 82.1 ± 2.7 | <.001*** |
| White race (n) | 202 (89.8) | 202 (89.4) | 201 (88.9) | 199 (88.1) | .944 |
| nonsmoker (n) | 83 (43.5) | 83 (43) | 96 (48.2) | 92 (44) | .647 |
| Education¶ (n) | 175 (77.8) | 183 (81) | 184 (81.4) | 191 (84.5) | .339 |
| Body fat (%) | 27.7 ± 6.6 | 27.8 ± 6.0 | 28.1 ± 5.1 | 27.8 ± 5.9 | .894 |
| BMI (kg/m2) | 25.4 ± 3.4 | 26.2 ± 3.5 | 27.2 ± 3.3 | 28.9 ± 3.8 | <.001*** |
| ALM (kg/m2) | 20.1 ± 2.1 | 21.5 ± 2.3 | 22.8 ± 2.3 | 25.4 ± 3 | <.001*** |
| PASE score | 103 ± 69.6 | 118.5 ± 63.5 | 125.7 ± 60.4 | 133.9 ± 64.1 | <.001*** |
| GDS (score) | 19 (8.4) | 17 (7.5) | 9 (4) | 7 (3.1) | .036* |
| Trails B (s) | 160.7 ± 70.8 | 143.8 ± 71.3 | 127.1 ± 61.8 | 124.9 ± 58.9 | <.001*** |
| MMSE score | 90.9 ± 7.2 | 91.6 ± 7.2 | 92.9 ± 6.8 | 93.7 ± 5.9 | <.001*** |
| Diabetes (n) | 42 (18.7) | 24 (10.6) | 49 (21.7) | 29 (12.8) | .004** |
| MI (n) | 41 (18.2) | 32 (14.2) | 27 (12) | 18 (8) | .012* |
| Multivitamin use (n) | 128 (57.7) | 117 (52.7) | 128 (57.1) | 118 (52.7) | .570 |
| Health status (good/excellent; n) | 182 (80.9) | 201 (88.9) | 204 (90.3) | 212 (93.8) | <.001*** |
Notes: D3-creatine (D3Cr), body mass index (BMI), appendicular lean mass (ALM) from dual-energy x-ray absorptiometry (DXA), physical activity scale for the elderly (PASE), geriatric depression score (GDS), Modified Mini-Mental State Examination (MMSE), myocardial infarction (MI).
†11.8 to <21 kg, n = 225.
‡21 to <23.7 kg, n = 226.
§23.7 to <26.7 kg, n = 226.
||26.7 to <36.2 kg, n = 226.
¶At least some college.
*p < 0.05, **p < 0.01, ***p < 0.001.