Presentation (CTI)

OBJECTIVES: Sex differences in myasthenia gravis (MG) are reported across epidemiology, clinical and patient-reported outcome (PRO) domains. Whether sex influences disease burden and engagement with research remains poorly understood. This study examined sex-based differences in patient-reported disease burden and PRO questionnaire engagement in adults with MG enrolled in the multi-country, longitudinal, real-world Vitaccess Real MG Registry (VRMG).
METHODS: VRMG collects data from neurologists, individuals’ electronic medical records and directly from MG patients. This study retrospectively analyzed data from adults with recorded sex and at least one completed PRO questionnaire (N=177). Disease burden was defined using PRO scores (MG Activities of Daily Living (MG-ADL), Fatigue score, MG Quality of Life-15 revised (MGQoL-15r) and Neuro-QoL Fatigue Short Form); engagement as completing 1+ PRO questionnaire. Median PRO questionnaire scores for males (n=91) and females (n=86) were compared cross-sectionally at registry enrolment (Wilcoxon tests) and longitudinally over the first 6 months (mixed models adjusted for age and years since diagnosis). Proportions of males vs. females completing at least one monthly PRO for the first 6 months were compared using one-proportion z-tests.
RESULTS: Males were significantly younger at registry entry (median 59 vs. 69 years, p<0.001). Time since diagnosis did not differ by sex (p=0.3). Baseline PRO scores were significantly higher in males across all PRO instruments (p<=0.001). Mixed models confirmed consistently elevated male scores over six months (p<0.05 for sex coefficient in each model). Engagement remained above 67% at six months (67.7% female, 71.9% male). There were no significant sex differences in PRO completion at any monthly timepoint.
CONCLUSIONS: Males in VRMG reported consistently higher disease burden than females. Equivalent engagement rates suggest this reflects genuine clinical heterogeneity rather than participation bias, supporting registry-derived estimates. Sex should be a stratifier in MG registry analyses, with implications for health economic modelling and real-world evidence generation in health technology assessment.