Body composition, sarcopenia, and frailty among Northern seasonal migrant older adults: a cross-sectional study

Abstract

Abstract Background To provide preliminary data on body composition, muscle health, nutritional status, and frailty among seasonal migrant older adults who overwinter in Hainan, and to identify potential health risks in this growing mobile aging population. Methods A cross-sectional study was conducted among 86 northern migrant elders recruited at Hainan Hospital of the PLA General Hospital between October 2023 and January 2024. Assessments included bioelectrical impedance analysis (BIA), handgrip strength, calf circumference, gait speed, Mini Nutritional Assessment-Short Form (MNA-SF), and frailty evaluation using the FRAIL scale. Adjusted comparisons and multivariable logistic regression were conducted to examine associations. Results No participant met the diagnostic criteria for sarcopenia. Despite regular physical activity and mostly normal nutritional status, excessive adiposity was prevalent: 74.4% exceeded body fat standards and 68.6% had visceral obesity. Early muscle weakness was evident, with 13.9% showing lower grip strength (adjusted P < 0.001). Participants at nutritional risk had significantly lower body mass index (BMI) (adjusted P = 0.0005), fat mass (adjusted P = 0.0040), visceral fat area (adjusted P = 0.0284), and appendicular skeletal muscle mass index (ASMI) (adjusted P = 0.0007). Prefrail individuals exhibited lower grip strength (adjusted P = 0.0116) and lower gait speed ( P < 0.001). Overall, risks of visceral obesity, early sarcopenia features, and prefrailty coexisted despite the absence of diagnosed sarcopenia. Conclusions Seasonal migrant older adults show active lifestyles yet significant hidden vulnerabilities. Strategies including routine screening, resistance training, and nutritional optimization may valuable in future preventive interventions, though further evaluation is required. Clinical trial number ChiCTR2300073205.