Nearly a quarter of strong opioid use among patients with rheumatoid arthritis is potentially attributable to obesity and its associated comorbidities, according to data published in Arthritis Care & Research.
“Chronic opioid use has been recognized as an important public health problem, and patients with arthritis commonly experience chronic pain that can lead to the use of these drugs,” Joshua F. Baker, MD, MSCE, of the University of Pennsylvania and the Philadelphia VA Medical Center, told Healio Rheumatology. “It's important to understand what factors lead to chronic use of opioids in order to learn how we might prevent this outcome.”
To analyze whether the rate of incident chronic opioid use is higher among patients with obesity in the rheumatoid arthritis population, Baker and colleagues studied data from Forward, The National Databank for Rheumatic Diseases. According to the researchers, Forward is a patient-based multi-disease, multi-purpose rheumatic disease registry with patients enrolled from community-based rheumatology practices across the United States, and followed-up with bi-annual questionnaires. Focusing on data from Jan. 1, 1999, to Feb. 28, 2019, the researchers included 19,794 individuals with RA in their study.
All Forward participants had been asked about their use of weak and strong opioid medications. Baker and colleagues defined chronic opioid use as new reported use extending through two contiguous follow-up questionnaires — roughly a period of 7 to 12 months. The researchers used Cox proportional hazards models to examine associations between baseline BMI and incident chronic opioid use, as well as predict 5-year cumulative incidence. These models adjusted for demographics, smoking, disease duration, RA treatments, household income and education level.
Investigators reported that 2,802 of the included participants experienced an episode of chronic opioid use during a total of 93,254 person-years of follow-up. Higher BMI was associated with a higher risk for chronic opioid use. For example, severe obesity — defined as a BMI greater than 35 kg/m — was associated with a higher risk for both overall opioid use (HR = 1.74; 95% CI, 1.72-2.04) and strong opioid use (HR = 2.11; 95% CI, 1.64-2.71), compared with the normal BMI range. Ultimately, the attributable risk linked to obesity was 15% for overall opioid use, and 24% for strong opioid use.
According to Baker and colleagues, this association was partially due to greater comorbidity, pain, and disability in patients with obesity.
“These findings are significant because they suggest that interventions to prevent or reverse obesity in this population would have an important effect on reducing the use of these drugs in the long-term,” Baker said. “These observations therefore add to the already substantial evidence that the obesity epidemic needs greater public health attention. They also further highlight that obesity remains an important and common problem in patients with rheumatoid arthritis with important long-term implications for health.”