Background : Aging is associated with various changes in body composition, such as a decrease in muscle mass, bone mineral density, and an increase in body fat. We assumed that these changes were accompanied by decrease of IGF-1 level. We aimed to define relationship between IGF-1 level and muscle mass, muscle strength and physical function of the middle aged people and the elderly.
Method : In the cross-sectional study, subjects were included who had medical examination in the Ajou University health promotion center. Serum IGF-1 level was measured, and muscle mass was calculated by dual-energy X-ray absorptiometry (DXA). Muscle strength was measured by hand grip strength test and physical performance was tested by 2-m walking test.
Results : Mean IGF-1 level was 191.1 ± 50.8 ng /ml in men and was 168.3 ± 49.0 ng /ml in women respectively. Serum IGF-1 level was associated with muscle mass in both genders. Muscle strength and physical performance were positively associated with IGF-1 in women. We also investigated prevalence of sarcopenia based on the definition of European Working Group on Sarcopenia in Older People (EGWSOP) guideline. The prevalence of sarcopenia was associated with low serum IGF-1 level in women.
Conclusion : We observed IGF-I was associated with muscle mass in both genders and it was related with muscle strength and physical performance in women. In addition, prevalecnce of sarcopenia was associated with low serum IGF-1 level.