Table 2.
Associations of Muscle and Fat Measures With Physical Performance and Incident Outcomes
| Model 1: Independent Associationsa | Model 2: Bivariate Associationsb | Model 3: Associations Including 3 Measuresc | ||||||
|---|---|---|---|---|---|---|---|---|
| Tibial Muscle Density (mg/cm3) | D3Cr Muscle Mass (kg) | Total Body Fat (kg) | Tibial Muscle Density (mg/cm3) | D3Cr Muscle Mass (kg) | Tibial Muscle Density (mg/cm3) | D3Cr Muscle Mass (kg) | Total Body Fat (kg) | |
| Physical performance, β coefficient (95% CI) | ||||||||
| Walking speed (m/s) | 0.06 (0.05, 0.08)† | 0.08 (0.06, 0.09)† | –0.06 (–0.09, –0.03)† | 0.05 (0.03, 0.06)† | 0.06 (0.04, 0.07)† | 0.05 (0.03, 0.06)† | 0.06 (0.04, 0.08)† | 0.01 (–0.026, 0.04) |
| Maximum grip strength (kg) | 1.61 (1.17, 2.06)† | 2.28 (1.77, 2.79)† | –3.22 (–4.15, –2.29)† | 1.05 (0.59, 1.52)† | 1.85 (1.31, 2.39)† | 1.10 (0.63, 1.57)† | 1.37 (0.75, 1.99)† | –1.73 (–2.77, –0.68)† |
| Chair stands (N/10 s) | 0.61 (0.50, 0.71)† | 0.72 (0.60, 0.84)† | –0.76 (–0.98, –0.54)† | 0.45 (0.34, 0.55)† | 0.54 (0.42, 0.66)† | 0.43 (0.33, 0.54)† | 0.49 (0.35, 0.63)† | –0.23 (–0.46, 0.005) |
| Incident outcomes, relative risk (95% CI) | ||||||||
| Mobility limitation | 0.75 (0.64, 0.89)† | 0.76 (0.62, 0.93)‡ | 1.43 (1.01, 2.02)# | 0.79 (0.66, 0.94)‡ | 0.82 (0.66, 1.01) | 0.78 (0.66, 0.93)‡ | 0.86 (0.67, 1.11) | 1.20 (0.80, 1.81) |
| Mobility disability | 0.71 (0.57, 0.87)‡ | 0.54 (0.40, 0.72)† | 1.36 (0.83, 2.22) | 0.80 (0.64, 1.01) | 0.59 (0.43, 0.80)† | 0.82 (0.65, 1.04) | 0.53 (0.36, 0.78)‡ | 0.76 (0.42, 1.34) |
| All-cause mortality, hazard ratio (95% CI) |
0.76 (0.68, 0.86)† | 0.68 (0.58, 0.80)† | 1.27 (0.95, 1.70) | 0.82 (0.72, 0.93)‡ | 0.74 (0.62, 0.88)† | 0.84 (0.74, 0.96)‡ | 0.70 (0.57, 0.86)† | 0.90 (0.64, 1.25) |
Notes: Beta coefficients, relative risks, or hazard ratios and their 95% confidence intervals (CIs), per 1 unit standardized increase.
aEach association adjusted for age, clinic site, height, and weight.
bAdjusted for age, clinic site, height, weight, and including tibial muscle density and D3Cr muscle mass.
cAdjusted for age, clinic site, height, weight, and including D3Cr muscle mass, tibial muscle density, and total body fat measures.
† p ≤ .001. ‡p < .01. #p < .05.