Cost-effectiveness analysis of invasive EEG monitoring in drug-resistant epilepsy.

Purpose: Our aim was to determine the cost-effectiveness of two intracranial electroencephalography (iEEG) interventions: 1) stereoelectroencephalography (SEEG) and 2) placement of subdural grid electrodes (SDGs) both followed by resective surgery in patients with drug-resistant, partial-onset epilepsy, compared with medical management (MM) in Hungary from payer's perspective.

Methods: The incremental health gains and costs of iEEG interventions have been determined with a combination of a decision tree and prevalence Markov process model over a 30-year time horizon in a cost-utility analysis (CUA). To address the effect of parameter uncertainty on the incremental cost-effectiveness ratio (ICER), deterministic and probabilistic sensitivity analyses were performed.

Results: Our results showed that both SEEG and SDG interventions represent a more expensive but more effective strategy than MM representing the current standard of care. The total discounted cost of SEEG and SDG were € 32,760 and € 25,028 representing € 18,108 and € 10,375 additional cost compared with MM, respectively. However, they provide an additional 3.931 (in SEEG group) and 3.444 quality-adjusted life years (QALYs; in SDG group), correspondingly. Thus, the ICER of SEEG is € 4607 per QALY gain, while the ICER for SDG is € 3013 per QALY gain, compared with MM. At a cost-effectiveness threshold of € 41,058 per QALY in Hungary, both subtypes of iEEG interventions are cost-effective and provide good value for money.

Significance: Because of the high cost of implanting electrodes and monitoring, the invasive EEG for patients with refractory epilepsy is currently not available in the Hungarian national healthcare system. Our study demonstrated that these procedures in Hungary are cost-effective compared with the MM. As a result, the introduction of iEEG interventions to the reimbursement list of the National Health Insurance Fund Administration was initiated.