Insomnia - treatment pathways, costs and quality of life

BACKGROUND: Insomnia is perhaps the most common sleep disorder in the general population, and is characterised by a range of complaints around difficulties in initiating and maintaining sleep, together with impaired waking function. There is little quantitative information on treatment pathways, costs and outcomes. The aims of this New Zealand study were to determine from which healthcare practitioners patients with insomnia sought treatment, treatment pathways followed, the net costs of treatment and the quality of life improvements obtained. METHODS: The study was retrospective and prevalence based, and was both cost effectiveness (CEA) and a cost utility (CUA) analysis. Micro costing techniques were used and a societal analytic perspective was adopted. A deterministic decision tree model was used to estimate base case values, and a stochastic version, with Monte Carlo simulation, was used to perform sensitivity analysis. A probability and cost were attached to each event which enabled the costs for the treatment pathways and average treatment cost to be calculated. The inputs to the model were prevalence, event probabilities, resource utilisations, and unit costs. Direct costs and QALYs gained were evaluated. RESULTS: The total net benefit of treating a person with insomnia was $482 (the total base case cost of $145 less health costs avoided of $628). When these results were applied to the total at-risk population in New Zealand additional treatment costs incurred were $6.6 million, costs avoided $28.4 million and net benefits were $21.8 million. The incremental net benefit when insomnia was "successfully" treated was $3,072 per QALY gained. CONCLUSIONS: The study has brought to light a number of problems relating to the treatment of insomnia in New Zealand. There is both inadequate access to publicly funded treatment and insufficient publicly available information from which a consumer is able to make an informed decision on the treatment and provider options. This study suggests that successful treatment of insomnia leads to direct cost savings and improved quality of life.