Societal costs of obstructive sleep apnoea syndrome

Aim To estimate the societal costs of obstructive sleep apnoea syndrome (OSAS) in New Zealand and develop a simulation tool to evaluate treatment options. Method Treatment profiles, availability, uptake, and costs were based on services in the Wellington Region, and were used to develop a decision analytic model with micro costing of each potential outcome. Sensitivity analyses were conducted with 10,000 Monte Carlo simulations randomly varying each model parameter between high and low estimates. Results Total annual societal costs of OSAS for New Zealanders aged 30-60 years were estimated at $40 million (range $33-$90 million) or $419 per case, with accidents being the major contributor. This included 58% direct medical, 13% direct non-medical, 25% indirect, and 3% intangible costs. The estimated incremental net cost of treating OSAS was $389 per case treated (range $338-$427). The estimated incremental net direct medical cost per quality of life year (QALY) gained was $94 (range $56-$310). Conclusion The estimated incremental direct medical cost per QALY gained by OSAS treatment is well below the average QALY cost ($6865) for drugs selected by PHARMAC to receive government subsidy for use in the healthcare system. Thus, the analysis strongly supports the cost effectiveness of OSAS treatment.