Difference of Low Skeletal Muscle Index According to Recommended Protein Intake in Korean

ABSTRACT

BACKGROUND: Sarcopenia has become a major concern owing to its association with a high risk of fall or fracture and metabolic impairments. There is insufficient evidence to support the role of dietary protein intake in reducing the prevalence of sarcopenia. This study was conducted to investigate the variation in low skeletal muscle index (SMI) with the dietary levels of protein intake.METHODS: This study analyzed data of 3,482 male and 4,838 female aged 50 years or older from the Korean National Health and Nutrition Examination Survey (KNHNES) database (2008–2011). Low SMI was indicated by a value <0.789 in male and <0.512 in female. Multiple logistic regression was performed to analyze the association of SMI with protein intake, whereby it was tested whether the dietary intake of proteins met the estimated average requirement (EAR) or the reference nutrient intake (RNI) as stated in the dietary reference intake (DRI) for Koreans, 2015.RESULTS: Irrespective of sex, the prevalence of low SMI was significantly high when the protein intake did not meet the EAR or RNI. Following adjustment for covariates, the odds ratio (OR) for low SMI in subjects with unmet EARs was 1.63 (1.28–2.09) in male and 1.35 (1.10–1.66) in female. The OR for low SMI in subjects with unmet RNI was 1.74 (1.38–2.18) in male and 1.39 (1.14–1.69) in female.CONCLUSION: The prevalence of low SMI was significantly higher when the protein intake did not meet the EAR or RNI as stated in the DRI for Koreans.