Patients with ulcerative colitis who have a higher BMI are at an increased risk for failing biologic therapy, regardless of the dosing regimen, according to new research published in Alimentary Pharmacology & Therapeutics.
Obesity has long been associated with a higher risk for developing Crohn’s disease, but no such link has been observed for ulcerative colitis (UC). Siddarth Singh, MD, of the division of gastroenterology at the University of California San Diego, and colleagues sought to determine if obesity might affect these patients already seeking treatment for UC.
“We conducted a retrospective cohort study to evaluate the impact of obesity on response to biologic therapy in patients with UC,” they wrote. “We hypothesized that higher BMI is associated with an increased risk of treatment failure in biologic-treated patients with UC, particularly in a subset of patients treated with fixed-dose regimens.”
Singh and colleagues analyzed data from 160 patients with UC treated with biologics at a single center between 2011 and 2016. Half of the patients were men, about half were treated with Remicade (infliximab, Janssen), median age was 36 years (26 – 52) and median BMI was 24.3 kg/m2 (21.428.7).
The primary outcome was treatment failure based on a composite outcome of IBD-related surgery/hospitalization or treatment modification including dose escalation, treatment discontinuation or addition of corticosteroids. Secondary outcomes included risk for IBD-related surgery/hospitalization and endoscopic remission. Investigators conducted a proportional hazard analysis to determine the independent impact of BMI on clinical outcomes.
The researchers found that each 1 kg/m² increase in BMI correlated with a 4% increase in the risk for treatment failure (adjusted HR = 1.04; 95% CI, 1–1.08). Additionally, each 1 kg/m² increase in BMI corresponded to an 8% increased risk for surgery or hospitalization (aHR = 1.08; 95% CI, 1.02–1.14).
Singh and colleagues said their findings could have important clinical implications for managing UC in patients with obesity.
“In clinical practice, physicians may consider aggressive treatment and close proactive monitoring in patients with high BMI treated with biologic agents,” they wrote. “Some potential changes include empirically using higher doses of anti-TNF therapy in overweight and obese patients, frequent therapeutic drug monitoring and/or use of combination therapy with immunomodulators to increase drug concentration and decrease risk of immunogenicity.” – by Alex Young
Singh reports he has received research support from Pfizer and AbbVie. Please see the full study for all other authors’ relevant financial disclosures.