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.

Identification of high-risk groups for complication after arthroplasty: predictive value of patient's related risk factors.

BACKGROUND: Total joint arthroplasty (TJA) benefit patients with osteoarthritis (OA) and rheumatoid arthritis (RA). However, a specific approach to detect patients at higher risk of prosthetic joint infection (PJI) and mechanical complications is absent. The aim of this study is to identify groups at higher risk for infections and mechanical complications after TJA in patients with RA and OA based on their most significant predictors. METHODS: This is a hospital-based cohort study with 1150 recipients of TJA. Risk factors and comorbidities were assessed prior to the index surgery. Multivariate logistic and hazard regression were used to determine the relationship between risk factors and occurrence of complications after TJA. Odds ratios (OR), hazard ratios (HR), 95% confidence intervals (CI), and comparison between areas under the curve (AUC) using DeLong's method are presented. RESULTS: Complications were more frequent in subjects with RA, use of corticosteroids, and previous comorbidities: respiratory disease, infections, diabetes, anemia, mental and musculoskeletal comorbidities than in subjects without these risk factors, and these factors were predictors of infections and mechanical complications (P < 0.05). A model including these factors was superior to a model with only type of joint disease (OA/RA) or age and gender to detect infections or mechanical complications after TJA (P < 0.05 for difference between models). Complication risk proportionally increased with the presence of two or more comorbidities (P < 0.001). CONCLUSIONS: There are two groups at higher risk for infections after TJA: patients with OA with at least two risk factors and patients with RA, who usually present at least one of the risk factors for infection.