Role of central obesity on pain onset and its association with cardiovascular disease: a retrospective study of a hospital cohort of patients with osteoarthritis

OBJECTIVES: To determine the role of central obesity (CO) in the onset and severity of joint pain and in predicting cardiovascular disease (CVD) in subjects affected with osteoarthritis (OA). DESIGN: Retrospective analysis on the onset of OA joint pain and CO. Waist circumference (WC), Waist-to-height ratio andwaist-to-hip ratio (WHR) were measured at the interview and defined according to the WHO criteria. Cross-sectional analyses on the association of comorbidities, including CVD, pain severity (number of joints and pain score) and CO. SETTINGS AND PARTICIPANTS: Medical records and interviews of a hospital cohort study of 609 patients with OA. Analyses included analysis of variance, mean differences (MDs), SE and logistic regression. Areas under the receiver operating characteristic curve (AUROC) compared the predictive value of the sex-specific CVD models. OUTCOME MEASURES: Onset of OA joint pain (years) and severity according to body mass index (BMI) and WC categories. Predictive value of WC for CVD by sex. Education level, disability, smoking and alcohol use were used to adjust the analysis. RESULTS: Subjects with OA and CO by WHR started 2 years earlier with pain symptoms and had more joints affected than those without CO (MD=1.96 years, SE=0.95, p=0.04 and MD=0.32, SE=0.15 and p=0.04, respectively). Age and hypertension were associated with CVD in both genders, and NSAIDs use only in males. In addition, respiratory disease, hypercholesterolaemia, stairs difficulty, a wider WC and obesity were significant risk factors in females, improving 12.7% in the prediction of CVD cases, compared with only age and BMI (AUROCC=0.793 and 0.666, respectively, p=0.03 for the difference between AUROCs). CONCLUSION: CO is associated with the onset of joint pain, and all pain analysed variables. CO has a role in CVD in women affected with OA and might help predict CVD cases.