OBJECTIVES: Invasive meningococcal disease (IMD) is a rare but potentially fatal infection that can cause long-term disabilities in survivors. Previous studies have identified people with sequelae using International Classification of Diseases codes; however, this approach only captures a narrow range of potential outcomes. The current study aims to use a clustering method to identify patients who may have sequelae, allowing for a better quantification of the economic burden of IMD over time (up to 12 years following the index date).

METHODS: To describe long-term (3-12 years after index date) healthcare resource use and costs of IMD between 2008 and 2019, a retrospective, case-control, real-world study was conducted using the French National Insurance database (SNDS). To assess the long-term burden of IMD sequelae, a clustering method (K-modes method) was used to identify two distinct patient groups: CARE+ subgroup, which includes those with a care pathway suggesting sequelae; and CARE– subgroup, which includes those without consumption of care. Healthcare resource utilization (HCRU) variables were combined with socioeconomic factors (age and gender) for this purpose.

RESULTS: Cluster analysis identified 23% of IMD patients as CARE+. HRCU was higher in CARE+ patients than in CARE – patients and their associated controls. The average cost per capita for CARE+ patients was higher than that of their controls in the long term: €21,186 versus €6,583 for out-of-hospital costs and €16,532 versus €5,260 for hospital costs, during the long-term follow-up. The additional cost of care for CARE+ patients varied depending on the year of follow-up but was in average 2.2 times higher than for their associated controls.

CONCLUSIONS: This is the first study to use a clustering method to identify patients with higher HRCU, suggesting sequelae. These results are consistent with those reported in the literature, which also highlights the correlation between long-term sequelae of IMD and higher healthcare costs.