Objectives The purpose of this study was to analyze the association between the radiographic severity of knee osteoarthritis (OA) and 4 different categories of body composition: normal, sarcopenic nonobesity, nonsarcopenic obesity, and sarcopenic obesity
Methods This was a cross-sectional study using the data from 73 participants with primary knee osteoarthritis ACR criteria. Information on demographics, comorbidities and medication was gathered. Anthropometrical measurements included weight, height and waist circumference. Radiographic knee OA was performed in all patients (based on the classification of kellgren- lawrence). Appendicular skeletal muscle mass (ASM) and whole-body fat mass were measured using dual x-ray absorptiometry. Sarcopenia was defined as a skeletal muscle mass index =ASM/height2 <1.55kg/m2 in women and <7.26 kg/m2 in men according to Baumgartner anthropometric equation.
Results 73 patients were included with a mean age of 61.87±3.93 years with a female predominance (95.9%), the median disease duration was 48 month [21-78].The prevalence of each body composition category was as follows: 38.4% normal, 35.4% nonsarcopenic obesity, 4.1% sarcopenic nonobesity, and 4.2% sarcopenic obesity. In univariate analysis, compared with nonsarcopenic obesity participants, participants with sarcopenic obesity were significantly older, had lower ASM, higher whole-body fat mass, and higher waist circumference. However, there was no significant difference in body weight or BMI. In multivariate analysis, sarcopenic obesity was more closely associated with radiographic severity of knee OA than was nonsarcopenic obesity. Sarcopenic nonobesity showed no significant association with knee OA.
Conclusions Sarcopenic obesity was more closely associated with radiographic severity of knee OA than was nonsarcopenic obesity, although both groups had equivalent body weight. This finding supports the importance of the systemic metabolic effect of obesity in knee OA
Disclosure of Interest None declared