The Prevalence of Comorbidities and Their Association With Disability Progression in Individuals With Multiple Sclerosis: A Study From Brazil.

Background: Comorbidities negatively impact the course of multiple sclerosis (MS). Identifying them is essential, as they represent potentially modifiable prognostic factors that can adversely influence the disease course. However, comorbidity prevalence remains underexplored in certain populations, including in individuals in Brazil.

Methods: In this cross-sectional study, we describe the frequency of comorbidities and their correlation with MS disability progression in a Brazilian population by reviewing the medical records of patients from a single MS center in Brazil. Preexisting comorbidities and those present at the time of MS diagnosis were screened. We assessed the prevalence of comorbidities, their prevalence ratios (PR) and the association between them, their number, and the confirmed disability worsening (CDW) that emerged during the follow-up visits.

Results: Comorbidities were present in 68.9% of individuals. The most prevalent comorbidities included cardiovascular diseases (19.3%), migraine (13.3%), psychiatric disorders (12.4%), smoking (12.4%), autoimmune diseases (12.0%), respiratory diseases (10.3%), and neoplasms (5.6%). Patients with 1 comorbidity and those with multiple comorbidities (≥ 3) had a significant PR for CDW (2.67, P = .01; 1.25, P = .03, respectively). Cardiovascular and autoimmune diseases presented significant PR for CDW (2.28, P = .03; 4.2, P = .004, respectively).

Conclusions: Comorbidities are more prevalent among Brazilian individuals with MS than in the general population and are associated with disease progression. Identifying and managing them may mitigate their adverse effects on disease course.