The predictive value of body mass index, waist circumference, and triglycerides/ high-density lipoprotein cholesterol ratio in assessing severity in patients with knee osteoarthritis and metabolic syndrome

Background

Studies have shown the importance of metabolic factors like BMI, waist circumference, and lipid profile in predicting knee osteoarthritis severity. However, their predictive ability in knee osteoarthritis patients with metabolic syndrome still needs to be explored.

Objectives

Evaluate the predictive ability of Body mass index (BMI), waist circumference, and triglyceride/ High-density lipoprotein cholesterol (HDL-c) ratio in determining the severity of knee osteoarthritis in patients with metabolic syndrome.

Materials and methods

A cross-sectional study at Ho Chi Minh City Hospital for Rehabilitation and Professional Diseases from January 2023 to January 2024 included 697 patients meeting ACR 1991 and NCEP-ATP III criteria for knee osteoarthritis and metabolic syndrome, respectively. Logistic regression analyzed the predictive ability of BMI, waist circumference, and triglyceride/HDL-C ratios. Six hundred ninety-seven patients were divided into two groups: severe and non-severe knee osteoarthritis. The criteria for severity were defined as the presence of both: (1) Kellgren-Lawrence grade 3 or higher on knee radiographs and (2) moderate or higher knee pain. Two models were constructed to analyze the predictive ability of severe knee osteoarthritis. Model 1 included univariate factors, while Model 2 incorporated multivariate models.

Results

Among the 697 patients who participated in the study, the average age was 58.7 ± 12.1 years, and females accounted for 71.3 %. The mean BMI and waist circumference were 24.8 ± 2.0 kg/m² and 86.2 ± 6.0 cm, respectively. In model 1 (univariate), the discriminative ability of BMI, waist circumference, and triglycerides/HDL-c in predicting severity was excellent, with respective AUCs of 0.90 (95 % CI: 0.87–0.92, p < 0.001), 0.81 (95 % CI: 0.78–0.85, p < 0.001), and 0.85 (95 % CI: 0.82–0.88, p < 0.001). In model 2 (combined model), the combination of all three factors resulted in an AUC of 0.93 (95 % CI: 0.91–0.95, p < 0.001) with a specificity of up to 90.2 %.

Conclusion

BMI, waist circumference, and triglyceride/HDL-C ratio are individual and combined predictors of knee osteoarthritis severity in patients with metabolic syndrome.