Diagnostic cut-offs, prevalence, and biochemical predictors of sarcopenia in healthy Indian adults: The Sarcopenia-Chandigarh Urban Bone Epidemiological Study (Sarco-CUBES)

Abstract

Purpose: Comprehensive data on diagnosis and prevalence of sarcopenia in India are lacking. The present study was undertaken to determine cut-offs for low muscle strength (MS) and low muscle mass (MM), and find out the prevalence of sarcopenia in Indians.

Methods: Apparently healthy individuals aged ≥ 20 years with no prior history of any co-morbidities were recruited from community by door-to-door survey. Participants eligible for study underwent blood sampling. Individuals identified as having biochemical abnormalities that could potentially affect MS and MM were excluded. Enrolled participants underwent DEXA. Muscle mass, MS, and physical performance were expressed as appendicular skeletal muscle index (ASMI), dominant handgrip strength (HGS), and usual gait speed (GS), respectively. Cut-offs for low MS and MM were defined as HGS and ASMI 2SD < mean of young reference population (20-39 years). A GS ≤ 0.8 m/s defined poor physical performance. Using them, the prevalence of sarcopenia was estimated as per EWGSOP2 recommendations.

Results: After exclusion, 804 participants were enrolled (mean age = 44.4 years). Peak HGS, ASMI, and GS were achieved in the 3rd/4th decades. Muscle strength/mass was lower than Caucasians. A HGS < 27.5 kg (males)/18.0 kg (females) and an ASMI < 6.11 kg/m² (males)/4.61 kg/m² (females) defined low MS and MM, respectively. Accordingly, prevalence of 'probable sarcopenia', 'sarcopenia', and 'severe sarcopenia' was 14.6%, 3.2%, and 2.3%, respectively. Corresponding values were higher when European cut-offs were used. Only serum testosterone positively predicted HGS/ASMI/GS in males.

Conclusions: Indians have low MS/MM, and hence, indigenous and not Western cut-offs should be used to define sarcopenia in Indians.

Keywords: Gait speed; India; Muscle mass; Muscle strength; Sarcopenia.