Female hormonal exposures and neuromyelitis optica symptom onset in a multicenter study.

Objective: To study the association between hormonal exposures and disease onset in a cohort of women with neuromyelitis optica spectrum disorder (NMOSD).

Methods: Reproductive history and hormone use were assessed using a standardized reproductive survey administered to women with NMOSD (82% aquaporin-4 antibody positive) at 8 clinical centers. Using multivariable regression, we examined the association between reproductive exposures and age at first symptom onset (FS).

Results: Among 217 respondents, the mean age at menarche was 12.8 years (SD 1.7). The mean number of pregnancies was 2.1 (SD 1.6), including 0.3 (SD 0.7) occurring after onset of NMOSD symptoms. In the 117 participants who were postmenopausal at the time of the questionnaire, 70% reported natural menopause (mean age: 48.9 years [SD 3.9]); fewer than 30% reported systemic hormone therapy (HT) use. Mean FS age was 40.1 years (SD 14.2). Ever-use of systemic hormonal contraceptives (HC) was marginally associated with earlier FS (39 vs 43 years, = 0.05). Because HC use may decrease parity, when we included both variables in the model, the association between HC use and FS age became more significant (estimate = 2.7, = 0.007). Among postmenopausal participants, 24% reported NMOSD onset within 2 years of (before or after) menopause. Among these participants, there was no association between age at menopause or HT use and age at NMOSD onset.

Conclusions: Overall, age at NMOSD onset did not show a strong relationship with endogenous hormonal exposures. An earlier onset age did appear to be marginally associated with systemic HC exposure, an association that requires confirmation in future studies.