Objective: To estimate the cost-effectiveness of using continuous positive airway pressure (CPAP) in the management of patients suffering from severe obstructive sleep apnoea/hypopnoea syndrome (OSAHS), compared to no treatment, from the perspective of the UK's National Health Service (NHS).
Methods: A Markov model was constructed to assess the cost-effectiveness of CPAP compared to no treatment. The model depicted the management of a 55 year old patient with severe OSAHS as defined by an apnoea-hypopnoea index (AHI) >30 and daytime sleepiness (Epworth scale score >12). The model spans a period of 14 years.
Results: According to the model, 57% of untreated patients are expected to be alive at the end of 14 years compared to 72% of CPAP-treated patients. Untreated patients are expected to cost the NHS £10,645 (95% CI: £7,988; £14,098) per patient over 14 years compared to £9,672 (95% CI: £8,057; £12,860) per CPAP-treated patients. Treatment with CPAP for a period of one year was found not to be a cost-effective option since the cost per QALY gained is expected to be >£20,000, but after two years of treatment the cost per QALY gained is expected to be £10,000 or less and after 13 years of treatment, CPAP becomes a dominant treatment (i.e. more effective than no treatment for less cost).
Conclusion: Within the limitations of our model, CPAP was found to be clinically more effective than no treatment and the cost-effective strategy, from the perspective of the UK's NHS, after a minimum of 2 years' treatment.