Associations of insulin-like growth factor-1 with gait vigor, symmetry, and stability metrics measured by wearable sensors in older adults.

BACKGROUND

Insulin-like growth factor-1 (IGF-1) is a hormone associated with metabolic function and cellular growth. This study investigates the relationship between plasma IGF-1 levels and digital gait characteristics in older adults.

METHODS

Six hundred forty two older adults completed gait measurements and provided blood samples. Wearable sensors were used to measure periodic, kinetic, and spatiotemporal gait parameters. The asymmetry index (AI) and coefficient of variation (CV) were calculated for each parameter. Plasma IGF-1 and related biomarkers were measured. Multiple linear regressions were employed to examine the associations between IGF-1 and gait parameters.

RESULTS

The mean age was 70.46 ± 6.13 years. After adjusting for all covariates, IGF-1 levels (per 1-SD increase) were positively associated with thigh acceleration (β = 0.055, P = 0.001), thigh swing work (β = 0.023, P = 0.004), ground reaction force (β = 0.048, P = 0.001), landing control force (β = 0.151, P < 0.001), gait speed (β = 1.105, P = 0.025), stride frequency (β = 1.223, P = 0.024), and stride length (β = 0.013, P = 0.012). The associations of IGF-1 with kinetic gait parameters and stride length remained significant after false discovery rate correction. Higher IGF-1 levels were associated with lower AIs for thigh acceleration and landing control force, and with lower CVs for swing time, thigh acceleration, landing control force, and toe-off angle. We identified biomarkers concurrently correlated with both IGF-1 and gait characteristics, including albumin, uric acid, leptin, myostatin, brain-derived neurotrophic factor, interleukin-6, superoxide dismutase, and glutathione reductase.

CONCLUSION

Higher circulating IGF-1 levels are associated with better multidimensional gait performance in community-dwelling older adults. The concurrent correlations between IGF-1, gait metrics, and related biomarkers provide preliminary clues for potential biological pathways involving energy metabolism, inflammatory regulation, antioxidation, and neural function, which require validation in future experimental studies.

TRIAL REGISTRATION: Not applicable.