Studies have demonstrated that, among patients with rheumatoid arthritis (RA), being overweight or obese appears to be protective against adverse cardiovascular outcomes and mortality, with underweight individuals having the highest relative mortality risk.
To look into this “obesity paradox” further, Bryant England, MD, and colleagues conducted a study—published in Arthritis Care & Research—to examine associations of BMI and weight loss with cause‐specific mortality in patients with RA. “Being obese is a snapshot of where someone’s body weight is at one point in time,” says Dr. England. “But having that information as a clinician doesn’t give you the trajectory. We wanted to look at the trajectory. Is it really being obese? Or is it that patients are not losing weight due to an underlying comorbid condition?” The study team analyzed United States veterans (90% male) with RA until death or through 2013. Weight loss was calculated as the annualized rate of change over the preceding 13 months, and cumulative percent.
Among 1,600 participants and nearly 6,000 patient‐years of follow-up, 303 deaths occurred (95 cardiovascular-related, 74 cancer-related, and 46 respiratory-related). The highest weight‐loss rate and weight‐loss percent were associated with a higher risk of cardiovascular mortality and cancer mortality. Overweight BMI was protective of cardiovascular mortality, while underweight BMI was associated with a nearly three‐fold increased risk of respiratory mortality.
Dr. England stresses that while previous studies have shown that obesity is protective against mortality for patients with RA, being overweight or obese is not a healthy, long-term solution for this patient population.
England B, Baker, J, Sayles H, Body Mass Index, Weight Loss, and Cause‐Specific Mortality in Rheumatoid Arthritis. Arthritis Care Res. 2018; 1, 11-18. Available at: https://onlinelibrary.wiley.com/doi/epdf/10.1002/acr.23258