Prevalence of metabolic syndrome and its associated factors in Chinese patients with ankylosing spondylitis

Purpose: We assessed the prevalence of metabolic syndrome (MetS) and associated factors in mainland Chinese patients with ankylosing spondylitis (AS). Patients and methods: A retrospective study was conducted in 117 AS patients and 117 age- and sex-matched healthy controls. Parameters of MetS based on the criteria established by the Chinese Diabetes Society in 2013 were tabulated. Demographic features, laboratory data, and clinical characteristics were also collected. Independent factors correlated with MetS in AS patients were identified by backward stepwise multivariate analysis. Results: The prevalence of MetS was higher in AS patients than in healthy controls (P= 0.026). AS patients also had higher blood pressure and fasting serum glucose levels, but generally lower serum lipid levels. AS patients with and without MetS had no distinct differences in disease duration, medication usage, disease activity, or biomarkers of inflammation. Multivariable logistic regression analysis showed that hyperuricemia (odds ratio [OR] = 2.385, 95% confidence interval [95% CI] = 1.019–5.582, P= 0.045) and high body mass index (BMI, OR = 5.165; 95% CI = 1.935–13.787, P=0.001) were independent factors for MetS in AS patients. Conclusion: Chinese AS patients living in the mainland have an increased risk of developing MetS. Hyperuricemia and high BMI are predictors of MetS in AS patients.