This study examines the association between recent weight loss and the risk of death among a large US cohort of people with rheumatoid arthritis (RA). It shows that, in contrast to the general population, low body mass index (BMI) and weight loss are associated with greater risk of mortality in RA.

A sample of 1,674 participants from the Veterans Affairs (VA) RA registry was included, and 312 death occurred over 9,183 person-years during the study. Maximum BMI and date of death were obtained from VA medical records. BMI was recorded for each study visit, and the annualized rate of loss was determined from changes (per year) in BMI over visits in the preceding 13 months.

Results show that a loss in BMI of ≥1 kg/m² was associated with a greater risk of death after adjusting for demographics, comorbidities, BMI, smoking, and RA therapies.

Weight loss at an annualized rate of ≥3 kg/m² was associated with the greatest risk of death.

Low BMI (<20 kg/m²) in people who were maximally obese (>30 kg/m²) and lost a lot of weight from maximum past weight, was also associated with the greatest risk.

Researchers conclude that weight loss is a strong predictor of risk of death in RA, and the greater the rate of weight loss, the higher the risk of mortality. They recommend that RA patients who experience unintentional weight loss be monitored closely.