Body composition assessment for sarcopenic obesity and 3-year mortality in older adults: A comparison study

There is no universally accepted definition of sarcopenic obesity (SO), and its prevalence is ambiguous. This study aimed to investigate the prevalence of SO in older adults based on different definitions and determine which predicts all-cause mortality.

This prospective longitudinal follow-up study included outpatients aged ≥60 years. SO was defined by sarcopenia definition based on the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria plus obesity. Three different methods were used to define obesity. Body mass index (BMI) ≥ 30 kg/m², waist circumference (WC) ≥ 102 cm for men and ≥88.0 cm for women, and body fat percentage (BF%) ≥ 37.3% for men and ≥51.1% for women. Different definitions of SO and their mortality predictions were compared.

The median age of the 584 patients in the study was 70.0 (interquartile range, 66.0-76.0) years. The prevalence of sarcopenia was 38.5% (47.5% in men and 35.7% in women). The prevalence of SO based on BMI, WC, and BF% was 15.3%, 16.4%, and 10.5%, respectively. The mortality rate was 6.7%. SO based on BMI (odds ratio [OR], 2.73; 95% CI, 1.12-17.9; P = 0.024) and BF% (OR, 1.43; 95% CI, 1.19-3.02; P = 0.007) were significantly associated with 3-year mortality after adjusting for the confounding variables of age, sex, and number of comorbidities. SO based on WC was not associated with mortality (OR, 0.78; 95% CI, 0.07-1.27; P = 0.104).

The use of BF% and BMI for defining SO is appropriate in outpatient older adults.