OBJECTIVES : Invasive meningococcal disease (IMD) is an uncommon but still life-threatening disease in industrialized countries, and its economic burden is not well known in France. This study aimed to describe the economic burden of IMD.

METHODS : An observational retrospective case-control cost-of-illness study was conducted from the SNIIR-AM database (A French national healthcare claim system of nearly 66 million patients). Cases comprised all patients with an index hospitalization (first hospitalization for IMD identified by the A39 ICD10 code), recorded between 01-Jan-2012 and 31-Dec-2017, and followed up for health care consumptions and costs until either death or study end. Controls were matched to cases (ratio 3:1) for age, gender and geographical area. Sequelae were identified with algorithms on ICD codes, treatment, medical procedures. The cost analysis was performed from the societal perspective.

RESULTS : There were 3,532 hospitalized patients for IMD; 22% aged 0-2 years and 19.6% aged 15-24 years; median age was 21 years, and 52% were males. The mean (± Standard Deviation-SD) duration of the index hospitalization was 14.8 (±24.0) days. There were 23.3% of the cases with at least one sequela. During the first year following index IMD event, outpatient visits to hospital-based specialist were about two times higher than controls (70.6% vs 38.7%). Cases received more frequent nursing care (46.4% vs 29.2%), physiotherapy (22.6% vs 17.4%) and speech therapy (3.3% vs 2.2%) compared to controls. Mean cost of the index IMD hospitalization was €11,269. During the first year following index IMD hospitalization, mean costs (index IMD hospitalization costs excluded) were €6,554 for cases and €2,890 for controls. Costs of outpatients were 3,153 € for cases and 1,456 € for controls. Index hospitalization costs varied from €9,393 in cases without sequelae to €22,537 in those with multiple sequelae.

CONCLUSIONS : This study provides strong real-world evidence on the substantial economic IMD burden.