Menopause does not modify disability trajectories in a longitudinal cohort of women with clinically isolated syndrome and multiple sclerosis followed from disease onset

BACKGROUND AND PURPOSE To evaluate the effect of menopause on disability accumulation in women followed from their clinically isolated syndrome (CIS). METHODS We examined the longitudinal changes in Expanded Disability Status Scale (EDSS) scores from CIS until the last follow-up in women belonging to the Barcelona CIS prospective cohort, followed through their menopausal transition. The analysis is based on 13,718 EDSS measurements, with an average of 28 EDSS measurements per patient. Differences in EDSS trajectories between menopausal and nonmenopausal women, controlling for age and disease duration, were evaluated. We performed two sensitivity analyses in women with confirmed MS and in those experiencing early menopause. RESULTS From 764 eligible women, 496 (65%) responded to the questionnaire, and 74 (14.9%) reached menopause over the follow-up. We did not find a significant inflection point in EDSS trajectories around menopause (slope change -0.009; 95% CI -0.066; 0.046). The annual increase in EDSS over the complete course of the disease was significantly higher in menopausal women (0.049; 95% CI, 0.026-0.074) versus nonmenopausal (0.019; 95% CI, 0.008-0.031; interaction p value 0.025). This difference was lost when controlling for age and disease duration (EDSS annual increase of 0.059; 95% CI, 0.025-0.094 vs. 0.038; 95% CI, 0.021-0.057, respectively; interaction p value 0.321). No inflection point was detected when the analysis was restricted to women with confirmed MS or with earlier menopause. CONCLUSIONS Menopause is not associated with an increased risk of disability in a CIS population, considering EDSS trajectories throughout the course of the disease together with age and disease duration.