Knee Osteoarthritis and Metabolic Disorders: Practical Aspects from Primary Healthcare

Background/Objectives: Knee osteoarthritis (KOA) is one of the most common musculoskeletal disorders worldwide, causing pain and disability. In addition to mechanical overload, increasing evidence suggests that metabolic disorders and abdominal obesity may contribute to the pathogenesis and progression of OA through mild inflammation and metabolic dysregulation. Methods: This cross-sectional, single-center study included 108 patients with radiologically confirmed KOA and 33 control subjects aged 45-80 years. KOA severity was assessed using the Kellgren-Lawrence scale and the Osteoarthritis Research Society International (OARSI) scale. Anthropometric and metabolic measurements, namely body mass index (BMI), waist-to-height ratio (WHtR), body shape index (ABSI), body roundness index (BRI), lipid accumulation product (LAP), visceral adiposity index (VAI), and dysfunctional obesity index (DAI), were analyzed. Correlation and multivariate regression analyses were performed to identify factors associated with KOA severity. Results: Over 85% of KOA patients were overweight or obese, and 63.9% met the criteria for metabolic syndrome. KOA patients had a significantly higher BMI, WHtR, waist circumference, BRI, LAP, and a higher prevalence of obesity than the control group. WHtR, BRI, and serum glucose levels positively correlated with OARSI scores. In multivariate linear regression analysis, age remained the only independent predictor of higher OARSI scores. Saturated fat intake exceeded recommended levels in both groups, but macronutrient intake was not associated with KOA severity. Conclusions: Age is the strongest independent predictor of structural KOA severity; however, visceral fat distribution and serum glucose levels correlate with the OARSI score, and modifying them may help improve cardiometabolic health in patients with KOA.