Prevalence of Sarcopenic Obesity in Adults with Class II/III Obesity Using Different Diagnostic Criteria

Abstract

Background/Objective. Sarcopenic obesity (SO) is a hidden condition of reduced lean soft tissue (LST) in context of excess adiposity. SO is most commonly reported in older adults and both its risk and prevalence increase with age. A variety of body composition indices and cut points have been used to define this condition, leading to conflicting prevalence and risk prediction. Here, we investigate variability in the prevalence of SO in an adult sample of individuals with class II/III obesity (BMI ≥ 35 kg/m²) using different diagnostic criteria. Methods. SO definitions were identified from a literature review of studies using dual-energy X-ray absorptiometry (DXA) to assess LST. Demographics, anthropometrics, and body composition (by DXA) were measured in n = 120, 86% female (46.9 ± 11.1 years). Results. LST was extremely variable in individuals, even with similar body sizes, and observed across the age spectrum. The prevalence of SO ranged from 0 to 84.5% in females and 0 to 100% in males, depending upon the definition applied, with higher prevalence among definitions accounting for measures of body size or fat mass. Conclusion. SO is present, yet variable, in adults with class II/III obesity. Accounting for body mass or fat mass may identify a higher number of individuals with SO, although risk prediction remains to be studied.

Figure 1

Variability of lean soft tissue by (a) body mass index (BMI) and (b) weight in adults with class II/III obesity (n = 120, females = 103). The box illustrates selected examples of females with (a) the same BMI (40 kg/m²) but LST varying from 41.2 to 74.9 kg and (b) same weight (116 kg) but LST varying from 52.9 to 74.9 kg.

Figure 2

Variability of appendicular skeletal mass index (ASMI) by age (23–69 years) in adults with class II/III obesity (n = 120, females = 103). The line indicated the 20th percentile of ASMI for females; subjects below this level ranged in age from 24 to 69 years.

Figure 3

Body composition phenotype, by decile groups of appendicular skeletal mass index (ASMI) and fat mass index (FMI), for adults with class II/III obesity (n = 120, females = 103) [18].