Preventing Invasive Aspergillosis in Lung Transplant Recipients: A Cost-Utility Analysis.

Background Invasive aspergillosis (IA) is a major cause of morbidity and mortality in lung transplant recipients. While most centers use universal prophylaxis, others opt for pre-emptive treatment. The optimal prevention strategy remains uncertain.Objective To evaluate the cost-utility of universal antifungal prophylaxis versus pre-emptive therapy for preventing IA during the first post-transplant year, from an Ontario healthcare payer perspective.Methods A state transition model with a lifetime horizon was developed. Transition probabilities, utilities, and costs were sourced from the literature as well as individual patient data. The base-case analysis assumed a relative risk of IA of 0.61 (95% CI: 0.33 to1.12) with universal prophylaxis compared to pre-emptive therapy. Outcomes included cumulative IA risk, quality-adjusted life-years (QALYs), costs and incremental cost-effectiveness ratio (ICER). Incremental net health benefit (INHB) was calculated using a cost-effectiveness threshold of C$50,000 per QALY. Costs and QALYs were discounted at 1.5%. Deterministic and probabilistic sensitivity analyses were conducted.Results The lifetime IA risk was 15.6% with universal prophylaxis and 18.6% with pre-emptive therapy. Universal prophylaxis yielded more QALYs at higher cost, with an ICER of C$30,393 per QALY gained and an INHB of 0.03. Probabilistic sensitivity analysis showed universal prophylaxis was favored at cost-effectiveness thresholds above C$45,000, with considerable uncertainty in the C$35,000-C$45,000 range.Interpretation Universal prophylaxis was the preferred strategy in the base-case scenario, with an ICER below the commonly accepted threshold of C$50,000 per QALY. However, results were sensitive to model inputs, emphasizing the need for robust clinical trials directly comparing these strategies.