The relation between menarche and the age of first symptoms in a multiple sclerosis cohort

BACKGROUND: Previously, multiple sclerosis (MS) has been thought to be associated with changes in hormone levels. This study investigates the association between the age of menarche and the age of onset of the first symptoms of MS. METHODS: A complete list of patients diagnosed with MS in the province of Newfoundland and Labrador was constructed. The age of menarche for our entire relapsing remitting female MS (RRMS) population was requested by mailout survey. Age of symptom onset was ascertained by chart review. RESULTS: A 74% rate of return on the survey results was obtained (150 RRMS patients). A linear regression model demonstrated that the age of first symptoms increased by 1.16 years as the age of menarche increased by one year (R2 = 0.69, P = 0.04). Another analysis showed that the average age of first symptoms for women with reported menarche from 10 to 12 years was 28.96 years compared with 31.83 years for a reported menarche from 13 to 15 years, a significant difference (P = 0.047, t-test). CONCLUSIONS: This study suggests that menarche may be related to the pathogenesis of MS.