NMO often causes relapses leading to ED visits and inpatient hospitalizations. Little has been published about the direct and indirect economic burden of relapses to patients.

Participants were recruited through NMO-related Facebook groups (08–09/2021). Inclusion criteria were age >=18 years and self-reported NMO diagnosis. Participants completed a 20-minute survey about the quantity and outcomes of their ED visits and hospitalizations over the past three years. Primary outcomes were direct (out-of-pocket medical) and indirect (childcare and housework) costs.

Of 103 respondents (mean age 45.8 years; 85% female; 69% U.S. residents; 79% White, 15% Black, 9% Asian; 13% Hispanic/Latinx), the average NMO disease duration was 3.1 years (range <1–9). The median household income was 83,000USD. The average number of ED visits was 3.6, and the average number of hospital admissions (including inpatient rehabilitation stays) was 1.7, with a mean duration of 15 days. Hospitalizations were for new relapses (66%), NMO treatment (18%), and complications of prior relapses (16%).

Participants reported no out-of-pocket costs for 48% of ED visits and hospitalizations. For the 52% of events for which these costs were reported, the mean cost to participants for each event was 3326 USD (95%CI [2378,4274]). Participants reported indirect costs such as childcare and housework expenses for 26% of visits, with average cost of 1907 USD (95%CI [1159,2655]) per visit. Sixty-nine percent of participants lost income from not working because of hospital visits, and financial hardships were experienced in 59% of hospitalizations.