High-sensitivity C-reactive protein and mobility disability in older adults

OBJECTIVE: to determine the association of high sensitivity C-reactive protein (HsCRP) levels with a risk of mobility disability and decline in older adults with and without vascular disease. DESIGN: prospective cohort. SETTING: community-residing population. SUBJECTS: six hundred and twenty-four adults age 70 and older (62% women) with gait and HsCRP assessments. MAIN OUTCOME MEASURES: incident mobility disability (velocity <70 cm/s) and annual rates of decline on gait velocity. RESULTS: elevated HsCRP levels (≥ 3 mg/l) at baseline present in 224 of the 624 eligible subjects was associated with a faster annual decline in gait velocity of 0.91 cm/s (P=0.02). Subjects with elevated HsCRP levels had increased risk of mobility disability (hazard ratio: 1.85, 95% CI: 1.09-3.14). Each one-unit increase in log HsCRP levels in the 406 subjects without prevalent mobility disability was associated with increased risk of mobility disability (hazard ratio: 1.33, 95% CI: 1.05-1.68). The association of baseline HsCRP levels with mobility disability and decline was stronger in the 224 individuals without vascular disease. The associations were not significant in the 400 subjects with vascular disease. CONCLUSIONS: HsCRP levels predict mobility disability and accelerated decline in walking speed in older adults. These associations were stronger in those without vascular disease.