Increased follistatin associated with decreased gait speed among old adults.

Low gait speed is associated with inflammation and muscle strength. Follistatin, a glycosylated plasma protein, is involved in inflammatory diseases, bone metabolism, muscle strength and cognition. However, research regarding the relationship between follistatin and gait speed in elderly individuals is limited. In this study, we aimed to examine the association between follistatin and gait speed in older adults.This cross-sectional, observational study included 205 ambulatory individuals aged ≥ 65 years. The baseline measures included 15-foot walking time, a structured questionnaire, grip strength and biomarkers, including follistatin and myostatin levels. Multiple linear regression was used to determine the change in gait speed for each 1 pg/mL increase in serum follistatin level. An extended model approach with a quartile-based analysis of serum follistatin levels was conducted.In the linear regression model, the β coefficient, representing the change in gait speed for each 1 pg/mL increase in serum follistatin level, was -0·308 (P < 0·001). After additional adjustment for relevant covariates, the β coefficient changed slightly, although the negative correlation remained (all P ≤ 0·001). After controlling for multiple covariates, participants in the highest serum follistatin level quartile had a significantly lower gait speed than those in the lowest quartile (all P for trend < 0·001).A higher follistatin level was independently associated with lower gait speed in community-dwelling elderly individuals; this suggests that serum follistatin level may be an indicator of mobility in elderly persons and may more particularly represent lower extremity function.