Influence of Body Mass Index on B Lymphocyte Repopulation in Multiple Sclerosis Patients Treated with Anti-CD20 Therapy (P7-3.016)

Abstract

<h3>Objective:</h3> Investigate an association with BMI and early B cell repopulation in a large cohort of multiple sclerosis (MS) patients treated with CD20-depleting therapy <h3>Background:</h3> Findings from a prior retrospective cohort of 45 patients indicated larger body surface area (BSA) was associated with faster repopulation of B cells after CD20 depletion, attributed to underestimation of CD20-depleting therapy dosing for patients with high BSA. Body mass index (BMI) is also associated with increased MS risk and radiographic markers of disease in relapsing-remitting disease. We aimed to confirm an association with BMI and early B cell repopulation after CD20 depletion therapy in an approximately 4-fold larger sample of patients than prior data. <h3>Design/Methods:</h3> This is a retrospective cohort study at a single academic referral center. Patients were identified through chart review using ICD billing codes. Normal BMI was defined 18.5–25. Overweight/obese BMI was defined as 25 or greater. The outcome of interest was early B cell repopulation defined as presence of greater than or equal to 1% CD19 cells on serum lymphocyte subset profile. Logistic regression was used to compare the categorical outcome on the normal vs overweight/obese BMI groups. <h3>Results:</h3> An initial 405 patients were identified. After excluding patients with missing ocrelizumab infusion and lymphocyte subset data, a total sample size of 157 patients were analyzed. The mean age and female sex of the cohort were 51.8 years (SD 12.9) and 99 (63.1%), respectively. 67 (42.7%) patients were categorized having normal BMI (18.5–25) and 90 (57.3%) patients as overweight/obese BMI (&gt;25). The model revealed an effect of BMI: patients who were overweight/obese showed an increase in repopulation [Coef=0.49, SE=0.22, p=0.03]. There was no effect of sex or age. <h3>Conclusions:</h3> Our study provides supportive evidence that greater BMI is associated with B cell repopulation after CD20-depleting therapy. <b>Disclosure:</b> An immediate family member of Dr. Loeffler has received research support from National Science Foundation. The institution of an immediate family member of Dr. Loeffler has received research support from Amazon. Dr. Han has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Roche. Dr. Han has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Arena Pharmaceuticals.