Immunomodulatory Therapies Related to Comorbid Autoimmune Diseases in MS Patients

Background: Comorbidity of autoimmune diseases (AID) has been reported in multiple sclerosis (MS) patients. The relation between use of disease modifying therapies (DMT) and the occurrence of comorbid autoimmune diseases in MS patients is unclear. 

Objective:  To investigate type and prevalence of AID comorbidity occurring in MS patients treated with different DMT’s vs patients that remained DMT naïve  during a longitudinal follow up study.

Methods: Data was extracted from the New York State MS Consortium registry and comprised of subjects with a minimum of 5 years follow-up, known date of disease onset, and no report of AID prior to or at time of registration (n=314). Chi-square and independent samples t-tests were conducted to examine differences in AID occurrence between DMT naïve and DMT users. A general linear model was used to test differences in duration between symptom onset and first AID between the DMT users group and DMT naïve subjects, while adjusting for sex, age at symptom onset, Kurtzke Expanded Disability Status Scale (EDSS) at registration, and year of registration.

Results: Females represented 90.0% of the DMT naïve group and 85.1% of the DMT group. 89.5%  had occurring comorbid AID after DMT initiation, compared to 10.5% of the DMT naïve group. The most frequent AID was thyroid disease. The mean time from symptom onset to first AID was significantly shorter in the DMT user group (mean 192.1 (114.2) months) compared to DMT naïve group (mean 261.9 (106.7) months) (p=0.002). This effect remained after adjusting for confounders in regression modeling (p=0.000).

Conclusion: Comorbid AID may be triggered by use of immunomodulatory therapies in MS patients. Identifying risk factors associated with the development of AID in the context of DMT use warrants investigation. Our study results may contribute to identifying more appropriate personalized therapeutic management decisions for MS patients.