Range of invasive meningococcal disease sequelae and health economic application – a systematic and clinical review

BACKGROUND: Invasive meningococcal disease (IMD) is uncommon, life-threatening, with many diverse sequelae. The aims were to: 1) comprehensively characterise the sequelae; 2) have a systematic application for sequelae impact in economic evaluation (EE). METHODS: Sequelae categorised as physical/neurological or psychological/behavioural were identified from a systematic review of IMD observational studies (OS) and EEs in high-income countries (published 2001-2020). A comprehensive map and EE-relevant list, respectively, included physical/neurological sequelae reported in ≥2OS and ≥ 2OS + 2EE (≥1OS and ≥ 1OS + 1EE for psychological/behavioural). Sequelae proportions were selected from the highest quality studies reporting most sequelae. Three medical experts independently evaluated the clinical impact of findings. RESULTS: Sixty-Six OS and 34 EE reported IMD sequelae. The comprehensive map included 44 sequelae (30 physical/neurological, 14 psychological/behavioural), of which 18 (14 physical/neurological and 4 psychological/behavioural) were EE-relevant. Experts validated the study and identified gaps due to limited evidence, underreporting of psychological/behavioural sequelae in survivors/their families, and occurrence of multiple sequelae in the acute phase and long-term. CONCLUSIONS: The considerable burden of IMD sequelae on survivors and their families is potentially underestimated in EE, due to underreporting and poorly-defined subtle sequelae. When assessing IMD burden and potential interventions e.g., vaccination, sequelae range and duration, underreporting, and indirect burden on dependents should be considered.