Allergies Are Associated with Increased Disease Activity in Multiple Sclerosis (P2.187)

Abstract

Objective: To assess the association between previous history of allergies and multiple sclerosis (MS) activity. Background: Studies exploring the association between allergic diseases and MS risk have shown conflicting results. However, the association between allergies and MS activity has not been investigated. Design/Methods: Patients enrolled in the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women’s Hospital (CLIMB) study who completed a self-administered questionnaire on environmental, drug and food allergies were included in the analysis. Patients were classified into two groups: allergic (at least one known allergy was reported) or never-allergic (NA, no allergies were reported). Patients with clinically isolated syndrome or allergy to any disease modifying therapy were excluded. To compare the relapse rate since disease onset between both groups, we used a negative binomial regression model, adjusting for age at disease onset and sex and using disease duration (DD) as the offset parameter. Results: 922 (68[percnt]) allergic (21[percnt] males, mean age 49±12 years, mean DD 16±10 years) versus 427 (32[percnt]) NA patients (35[percnt] males, mean age 50±12, mean DD 16±11 years) were analyzed. Of the allergic patients, 238 (26[percnt]), 586 (64[percnt]) and 574 (62[percnt]) patients reported food, environmental and drug allergies, respectively. The adjusted relapse rate (ARR) was higher in the allergic group than in the NA group but this difference was not statistically significant (0.2516 vs. 0.2213; Wald p=0.1331). When we stratified by type of allergy, patients reporting any food allergy had a higher ARR than NA patients (0.2398 vs. 0.1893; Wald p=0.048). No significant differences in the ARR were found when comparing the environmental (p=0.1255) or drug (p=0.4339) groups with the NA group. Conclusions: Our findings suggest that patients who have food allergies have a more active disease than those without allergies. Exploration of allergy-associated immune mechanisms that modulate MS disease course is required.

Disclosure: Dr. Diaz-Cruz has received research support from Merck Serono. Dr. Chua has nothing to disclose. Dr. Healy has received research support from Merck Serono, Novartis and Genzyme. Dr. Sattarnezhad has received research support from Merck Serono. Dr. Glanz has received research support from Merck Serono. Dr. Weiner has nothing to disclose. Dr. Chitnis has received personal compensation for activities with Novartis and Biogen. Dr. Chitnis has received research support from Merck-Serono and Novartis Pharmaceuticals.