Stress, Multiple Sclerosis, and Everyday FunctioningA Review of the Literature with Implications for Intervention.

Numerous studies have described an association between stress and the onset or exacerbation of multiple sclerosis (MS). Most of the studies that have been conducted to date, however, have had methodological flaws including: (1) retrospective designs, (2) inadequate or absent control groups, (3) small sample sizes, (4) clinical measures that are insensitive to underlying disease activity, and (5) wide variation in the measurement of stress. Animal models of MS have enabled researchers to examine the effects of stress directly in the central nervous system. Stress affects three biological systems that may be dysregulated in MS: the neuroendocrine system, the sympathetic nervous system, and the serotonergic neurotransmitter system. Future stress-MS research should evaluate the relationship between stress and these systems.