Clinical studies have shown that groups of multiple sclerosis (MS) patients exhibit a chronically activated hypothalamo-pituitary-adrenal (HPA) axis. However, the association of HPA axis activity and disease progression in MS is unknown. In this longitudinal study over a 3-year follow-up period, we report that patients who exhibited stronger HPA reactivity at baseline were significantly more likely to experience progression as measured by the Expanded Disability Status Scale (EDSS) during the follow-up period. Furthermore, HPA axis activity correlated with progression ratings and cognitive impairment three years later. Tests of HPA axis activity may be useful biomarkers for disease progression in MS.
