Higher body mass index (BMI) was associated with higher risk for incident chronic opioid use among patients with obesity and rheumatoid arthritis (RA), according to study results published in Arthritis Care and Research.
In order to evaluate the rate of incident chronic opioid use among this patient population, investigators conducted a semiannual survey among patients who were a part of the National Databank for Rheumatic Diseases, Forward, from January 1, 1999 to February 28, 2019. Survey participants were categorized according to the World Health Organization body weight index (BWI) classifications of underweight (<18.5 kg/m2), normal weight (18.5-25 kg/m2), overweight (25-30 kg/m2), obese (30-35 kg/m2), and severely obese (35 kg/m2). Patients with a BMI <14 kg/m2 were excluded from participating in the study. The study models were adjusted for demographics, household income, smoking, disease duration, RA treatments, and educational level.
Of the patients who met inclusion criteria (n=19,794), 2802 reported an incident episode of chronic opioid use over 93,254 person-years of follow up.
Researchers found that patients with severe obesity were associated with a higher risk of overall opioid use (hazard ratio [HR], 1.74; P <.0001) and strong opioid use (HR, 2.11; P <.0001) compared to patients with a BMI of 18.5-25 kg/m2.
Greater pain, comorbidity and disability identified in obese groups partially explained increased opioid use. Furthermore, the risk of chronic strong opioid use was more than 2-fold higher for severe obesity compared to normal weight (HR, 2.11; P <.0001).
Limitations of this study included: self-reporting of BMI, which could have led to discrepancies among patient groups; a lack of generalizability considering risk factors may vary among different populations of patients with obesity; and the lack of information investigators had access to regarding the dosage of opioid medications.
Investigators note, “These data support a focus on the prevention and management of obesity in order to stem the use of chronic opioids in patients with arthritis.”
Baker JF, Stokes A, Pedro S, et al. Obesity and the risk of incident chronic opioid use in rheumatoid arthritis [published online May 31, 2020]. Arthritis Care Res. doi:10.1002/ACR.24341