The cost-effectiveness of seven behavioural interventions to prevent drug misuse in vulnerable populations.

BACKGROUND: The National Institute for Health and Care Excellence (NICE) developed a guideline on drug misuse prevention in vulnerable populations. Part of the guideline development process involved evaluating cost-effectiveness and determining which interventions represented good value for money.

METHODS: Economic models were developed for seven interventions which aimed to prevent drug use in vulnerable populations. The models compared the costs (to the health and crime sectors) and health benefits (in quality-adjusted life years (QALYs)) of each intervention and its comparator. Sensitivity analysis explored the uncertainty associated with the cost of each intervention and duration of its effect.

RESULTS: The reduction in drug use for each intervention partly offset the costs of the intervention, and improved health outcomes (QALYs). However, with high intervention costs and low QALY gains, none of the interventions were estimated to be cost-effective in the base case. Sensitivity analysis found that some of the interventions could be cost-effective if they could be delivered at a lower cost, or if the effect could be sustained for more than two years.

CONCLUSIONS: For drug misuse prevention to be prioritised by funders, the consequences of drug misuse need to be understood, and interventions need to be shown to be effective and cost-effective. Quantifying the wider harms of drug misuse and wider benefits of prevention interventions poses challenges in evaluating the cost-effectiveness of drug misuse prevention interventions. A greater understanding of the consequences of drug misuse and causal factors could facilitate development of cost-effective interventions to prevent drug misuse.