Table 3.
Participant Characteristics by Inflammatory Component Level: TNF-Related Component and CRP-Related Component (N = 1,269*)
| Variable | Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | P for Trend |
| TNF-α-related component | |||||
| Age (y) | 73.0 ± 2.9 | 73.5 ± 2.7 | 73.8 ± 2.9 | 74.1 ± 2.9 | <.001 |
| Black (%) | 65.1 | 43.7 | 30.8 | 25.2 | <.001 |
| Female (%) | 58.8 | 53.5 | 45.6 | 47.3 | .001 |
| Physical activity (kcal/wk) | 842 ± 1,431 | 1,074 ± 1,822 | 1,131 ± 1,989 | 1,045 ± 2,062 | .781† |
| Smoking (%) | |||||
| Never | 49.4 | 45.4 | 41.8 | 40.4 | |
| Current | 12.6 | 9.5 | 9.4 | 10.7 | .857 |
| Former | 38.1 | 45.1 | 48.7 | 48.9 | .005 |
| Alcohol use (%) | |||||
| None in past year | 50.6 | 47.8 | 49.5 | 58.5 | |
| Less than once/wk | 22.3 | 19.6 | 19.2 | 17.1 | .049 |
| Once to –seven times/week | 18.6 | 26.6 | 25.2 | 15.5 | .130 |
| More than seven times/wk | 8.5 | 6.0 | 6.0 | 8.9 | .725 |
| Prevalent clinical pulmonary disease (%) | 10.4 | 10.5 | 14.5 | 15.2 | .019 |
| Prevalent heart disease (%) | 21.8 | 29.1 | 35.3 | 31.2 | .003 |
| Prevalent diabetes (%) | |||||
| Not impaired | 61.3 | 60.8 | 65.5 | 58.9 | |
| Impaired fasting glucose | 17.7 | 19.9 | 16.8 | 16.6 | .620 |
| Diabetic fasting glucose | 4.8 | 5.6 | 2.5 | 2.2 | .037 |
| Known diabetic | 16.1 | 13.7 | 15.2 | 22.3 | .079 |
| Anti-inflammatory drug use (%) | 49.7 | 57.8 | 62.6 | 56.8 | .035 |
| Total lean mass (kg) | 46.4 ± 10.3 | 46.7 ± 10.1 | 47.5 ± 9.7 | 46.8 ± 9.8 | .4213 |
| Total fat mass (kg) | 26.6 ± 8.8 | 27.2 ± 9.2 | 27.4 ± 8.8 | 27.5 ± 8.8 | .2307 |
| Knee strength (Nm/kg) | 108.8 ± 42.8 | 106.1 ± 42.8 | 107.2 ± 37.7 | 102.5 ± 35.8 | .098 |
| 400-m walk time | 332.9 ± 59.9 | 328.8 ± 63.6 | 328.5 ± 71.6 | 335.8 ± 58.2 | .661† |
| Walking speed for 20 m | 1.30 ± 0.25 | 1.35± 0.27 | 1.34 ± 0.25 | 1.33 ± 0.25 | .210 |
| HPPB | 2.20 ± 0.51 | 2.17 ± 0.56 | 2.17 ± 0.57 | 2.08 ± 0.65 | .014 |
| Grip strength | 30.3 ± 10.5 | 29.6 ± 10.0 | 30.1 ± 10.4 | 29.0 ± 9.8 | .211† |
| CRP-related component | |||||
| Age (y) | 73.7 ± 2.8 | 73.8 ± 2.9 | 73.6 ± 2.9 | 73.4 ± 2.9 | .158 |
| Black (%) | 29.7 | 36.5 | 41.3 | 57.4 | <.001 |
| Female (%) | 47.3 | 49.4 | 51.7 | 56.8 | .014 |
| Physical activity (kcal/wk) | 1,305 ± 2,064 | 997 ± 1,712 | 918 ± 1,621 | 872 ± 1,922 | <.001† |
| Smoking (%) | |||||
| Never | 47.3 | 51.3 | 42.6 | 35.8 | |
| Current | 8.2 | 8.5 | 9.5 | 16.1 | <.001 |
| Former | 44.5 | 40.3 | 48.0 | 48.1 | .009 |
| Alcohol use (%) | |||||
| None in past year | 48.4 | 49.4 | 54.8 | 53.9 | |
| Less than once/wk | 19.6 | 23.6 | 18.4 | 16.7 | .088 |
| Once to seven times/wk | 25.0 | 22.3 | 19.9 | 18.6 | .027 |
| More than seven times/wk | 7.0 | 4.7 | 7.0 | 10.7 | .151 |
| Prevalent clinical pulmonary disease | 7.9 | 9.8 | 16.5 | 16.5 | <.001 |
| Prevalent heart disease | 20.4 | 28.4 | 32.1 | 36.6 | <.001 |
| Prevalent diabetes (%) | |||||
| Not impaired | 74.4 | 67.1 | 54.7 | 50.3 | |
| Impaired fasting glucose | 12.8 | 17.9 | 19.7 | 20.5 | <.001 |
| Diabetic fasting glucose | 1.3 | 1.9 | 5.2 | 6.7 | <.001 |
| Known diabetic | 11.5 | 13.1 | 20.4 | 22.4 | <.001 |
| Anti-inflammatory drug use (%) | 56.7 | 56.6 | 56.2 | 57.4 | .879 |
| Total lean mass (kg) | 45.5 ± 9.9 | 46.8 ± 10.5 | 47.0 ± 9.6 | 48.1 ± 9.6 | .0012 |
| Total fat mass (kg) | 22.9 ± 6.7 | 26.8 ± 8.2 | 27.6 ± 8.1 | 31.4 ± 10.2 | <.0001 |
| Knee strength (Nm/kg) | 108.1 ± 39.8 | 107.4 ± 39.7 | 105.7 ± 39.4 | 103.33 ± 41.1 | .143 |
| 400-m walk time | 315.1 ± 55.4 | 329.4 ± 56.0 | 335.6 ± 70.7 | 351.6 ± 69.2 | <.001† |
| Walking speed for 20 m | 1.40 ± 0.26 | 1.35± 0.25 | 1.32 ± 0.24 | 1.25 ± 0.25 | <.001 |
| HPPB | 2.32 ± 0.48 | 2.18 ± 0.58 | 2.14 ± 0.56 | 1.97 ± 0.62 | <.001 |
| Grip strength | 30.6 ± 10.7 | 30.2 ± 10.37 | 30.0 ± 9.85 | 28.1 ± 9.63 | .010† |
Notes: CRP = C-reactive protein; HPPB = Health ABC physical performance battery; TNF = tumor necrosis factor.
*
Sample size was 1,269 except for smoking (n = 1,268), alcohol use (n = 1,267), prevalent heart disease (n = 1,236), prevalent diabetes (n = 1,246), anti-inflammatory drug use (n = 1,266), total lean mass (n = 1,258), total fat mass (n = 1,258), knee strength (n = 1,099), 400-m walk time (n = 928), walking speed for 20 m (n = 1,095), HPPB (n = 1,246), and grip strength (n = 1,200).
†
After log transformation.