Obesity is an inflammatory condition associated with higher rheumatic disease (RD) incidence, increased disease activity, and functional impairment. We hypothesized that metabolic and bariatric surgery (MBS), through weight loss, decreases immunosuppressant use in patients with RDs.
We conducted a retrospective review of MBS procedures in patients using immunosuppressants for RDs between 2008-2020 at two academic institutions. Patient data were analyzed at 3-, 6-, 12-, and 24-month follow-up intervals. We examined paired differences in the number of medications taken at surgery relative to different post-surgical follow-up periods using McNemar tests for the prednisone-only comparisons and paired t-tests for all other comparisons.
We identified 56 patients with RDs who underwent MBS (mean age =53 years, mean follow-up =19 months). Sixty four percent of patients had Roux-en-Y gastric bypass, 30% sleeve gastrectomy, and 5% duodenal switch. Rheumatoid arthritis was the most common RD (43%), followed by psoriasis (18%), and lupus (11%) [Table1]. Mean percent total weight loss and Δ BMI were 34.2% and 10.3 kg/m² at 24 month follow-up. At 24 months, 11 patients (31%) stopped prednisone (p-value 0.004) and 13 (36%) showed a reduction in immunosuppressants (Disease-Modifying Anti-Rheumatic Drugs (DMARDs) or glucocorticoids) (p-value 0.01). One patient started glucocorticoids postoperatively and 2 had an increase in immunosuppressants [Table2]. At the last encounter, 5 patients were off immunosuppressants and all medication classes, except biological DMARDs, showed significant reductions.
There is significant decrease in utilization of immunosuppressants after MBS in patients with RDs. Further studies are needed to confirm correlation.