CREATING BIOMARKER BURDEN AND ROBUSTNESS INDICES FOR PHYSICAL PERFORMANCE IN OLDER ADULTS

The human aging process is associated with decline in physical performance resulting from dysregulated inflammatory and metabolic systems; each has an effect on circulating serum markers of inflammation and metabolism. Biomarker burden and robustness indices were developed from twenty inflammatory and metabolic markers using a combination of three cross-sectional studies conducted in older adults. Each biomarker was individually correlated with gait speed, and all biomarkers underwent selection by step-wise regression on multiple bootstrap samples with respect to burden and robustness of physical performance. Twelve and eight biomarkers, respectively, were included in the indices that correlated with steady, step-wise change in outcome. The biomarker indices predict physical performance better than individual markers and are the first of such indices to link multiple inflammatory/metabolic markers with physical performance. The biomarkers included in the model have physiological and clinical implications on development of, or resilience to, physical performance decline in the older adults.