This scoping review characterizes the co-occurrence, diagnostic sequence, and clinical relevance of immune-mediated comorbidities in people with multiple sclerosis (PwMS). It covers conditions including autoimmune thyroid disease, type 1 diabetes (T1D), psoriasis, inflammatory bowel disease (IBD), bullous pemphigoid, rheumatoid arthritis, systemic lupus erythematosus, vitiligo, atopic dermatitis, asthma, systemic sclerosis, and primary Sjögren's syndrome.
Autoimmune thyroid disease, T1D, psoriasis, IBD, and bullous pemphigoid showed some of the most recurrent evidence of higher co-occurrence with MS. Findings for rheumatoid arthritis, systemic lupus erythematosus, vitiligo, atopic dermatitis, asthma, and less frequently studied conditions were more variable. For diseases diagnosed after MS, associations were heterogeneous and condition-specific, with higher subsequent occurrence for psoriasis, IBD, and bullous pemphigoid in some populations. For immune-mediated diseases diagnosed before MS, higher estimates were reported for selected conditions including T1D, psoriasis, IBD, bullous pemphigoid, systemic sclerosis, and primary Sjögren's syndrome, though magnitude, precision, and consistency varied.
Evidence on MS activity, disability, or progression was limited and heterogeneous. A small number of studies indicated adverse disability or MRI outcomes associated with T1D, whereas findings for other conditions were mixed, outcome-specific, or inconclusive. The authors note that current evidence is insufficient to establish an MS prodrome or biologically distinct MS subgroups.
Potential explanations for the observed associations include shared susceptibility, surveillance bias, diagnostic delay, treatment exposure, residual confounding, or coincidental coexistence. Longitudinal studies are needed to clarify clinical and prognostic relevance.
How this fits prior evidence
This scoping review extends prior coverage of immune-mediated and neuroinflammatory mechanisms by mapping co-occurrence patterns across multiple autoimmune conditions in MS. It contrasts with the prior item on resistance training and BDNF in MS, which addressed a modifiable lifestyle factor with low-certainty evidence, by focusing instead on comorbid disease associations. The review's conclusion that evidence is insufficient to establish an MS prodrome or distinct subgroups aligns with the cautious framing used in prior coverage of immune dysregulation across rheumatologic and neurodegenerative conditions.
