(HealthDay News) – Being overweight or obese reduces the risk of all-cause mortality in rheumatoid arthritis (RA) patients, according to a study published in the October issue of Arthritis Care & Research.
Frederick Wolfe, MD, from the University of Kansas in Wichita, and Kaleb Michaud, PhD., from the University of Nebraska in Omaha, studied mortality in 24,535 patients over 12.3 years. Patients were categorized by age: <50 years, 50–70 years, and >70 years.
The researchers found that 63–68% were obese (body mass index [BMI], 30kg/m² or more) and 2% were underweight (BMI less than 18.5kg/m²). There was a reduction in the relative risk [RR] for all-cause and cardiovascular mortality in overweight (all-cause RR, 0.8; 95% confidence interval [CI], 0.8–0.9) and obese groups (all-cause RR, 0.8; 95% CI, 0.7–0.8), both with and without comorbidity adjustment. There was an increased mortality risk associated with being underweight (all-cause RR, 1.9; 95% CI, 1.7–2.3). However, compared with normal-weight, there was an increase in the risk of diabetes (odds ratio [OR], 4.8); hypertension (OR, 3.4); myocardial infarction (OR, 1.3); joint replacement (OR, 1.4); and work disability (OR, 1.9) among the obese. The obese group also had higher total semiannual direct medical costs ($1,683 more), lower annual household income ($6,481 less), higher pain scores, and lower EuroQol scores.
“Overweight and obesity reduce the RR of all-cause and cardiovascular mortality across different age groups and durations of RA,” the authors write.