Patients with antineutrophil cytoplasmic antibody–associated vasculitis (AAV), including granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), are often prescribed high doses of glucocorticoids and immunosuppressive medication, such as rituximab. Glucocorticoid treatment is commonly associated with weight gain. Despite the well-established link between glucocorticoid use and cardiovascular risk, weight gain is not always an adverse event due to the risks of weight loss associated with increased catabolic activity experienced by patients with these inflammatory conditions.
“The ability to classify increased BMI [body mass index] (e.g., weight gain) accurately as either an adverse event related to glucocorticoid exposure or a positive outcome reflecting improved disease activity is, therefore, important in studies investigating glucocorticoid-sparing strategies,” write Zachary S. Wallace, MD, and colleagues from Massachusetts General Hospital in Boston in their latest research, published in the July 2017 issue of Arthritis Care & Research.
Only one previous study, the Wegener’s Granulomatosis Etanercept Trial, has examined the relationship between AAV treatment and changes to patient BMI. It found weight gain was not associated with glucocorticoid exposure. In their latest research, Dr. Wallace and colleagues set out to replicate these findings, as well as investigate the relationship between increases in BMI and improved disease control.
The researchers used data from the Rituximab in ANCA-Associated Vasculitis (RAVE) trial, which included 197 participants with antineutrophil cytoplasmic antibody positivity with GPA or MPA and severe disease. In the RAVE trial, patients were randomized into two groups: one treated with cyclophosphamide and one with rituximab. Both groups received the same glucocorticoid protocol. Throughout the trial, glucocorticoid use, BMI and disease activity were measured regularly between baseline and 18 months.