BODY COMPOSITION IS MORE CLOSELY RELATED TO KNEE OSTEOARTHRITIS IN WOMEN THAN MEN: A CROSS-SECTIONAL STUDY USING KNHANES DATA

초록

Purpose (the aim of the study): This study aimed to assess the association between knee osteoarthritis (OA) and body composition parameters and to evaluate the impact of both obesity and lower extremity muscle mass on radiographic knee OA in relation to sex. Methods: Data from 4,246 participants aged 50 years and older were analyzed from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1,2). Body composition, including fat and muscle mass in the lower extremities, was measured using dual-energy X-ray absorptiometry. Logistic regression was employed to assess associations between knee OA and body composition quartiles by sex, adjusting for age, smoking, alcohol consumption, physical activity, diabetes, and hypertension. Results: In women, a higher fat mass and a lower lower extremity muscle mass were significantly associated with knee OA presence and severity (p < 0.05). The odds ratios (ORs) for knee OA increased across fat mass quartiles, whereas lower extremity muscle mass showed a decreasing trend (p < 0.05). These associations were not observed in men, indicating a sex-specific relationship between body composition and knee OA. Conclusions: Body composition, particularly lower extremity muscle mass, is more strongly correlated with knee OA in women than in men, suggesting that targeted prevention and management strategies focusing on muscle mass may benefit women with OA. Association between radiographic knee OA and the four subgroups classified according to BMI and percentage of muscle mass in both lower extremities Odds ratio (OR) and 95% confidence interval (95% CI); NN, non-obesity with a normal percentage of muscle mass in both lower extremities; NL, non-obesity with a low percentage of muscle mass in both lower extremities; ON, obesity with a normal percentage of muscle mass in both lower extremities; OL, obesity with a low percentage of muscle mass in both lower extremities.