Risk stratification for treating people at ultra-high risk for psychosis: A cost-effectiveness analysis

People who are at ultra-high risk (UHR) for psychosis receive clinical care with the aim to prevent first-episode psychosis (FEP), regardless of the risk of conversion to psychosis. An economic model from the Canadian health system perspective was developed to evaluate the cost-effectiveness of treating all with UHR compared to risk stratification over a 15-year time horizon, based on conversion probability, expected quality-of-life and costs. The analysis used a decision tree followed by a Markov model. Health states included: Not UHR, UHR with <20 % risk of conversion to FEP (based on the North American Prodrome Longitudinal Study risk calculator), UHR with ≥20 % risk, FEP, Remission, Post-FEP, and Death. The analysis found that: risk stratification (i.e., only treating those with ≥20 % risk) had lower costs ($1398) and quality-adjusted life-years (0.055 QALYs) per person compared to treating all. The incremental cost-effectiveness ratio for 'treat all' was $25,448/QALY, and suggests treating all may be cost-effective. The model was sensitive to changes to the probability of conversion.

Interventions for people at ultra-high risk for psychosis: A systematic review of economic evaluations

AIM

Psychotic disorders have long-term negative consequences for functioning and quality of life. Ultra-high risk (UHR) programs aim to identify and treat people during the prodromal period before their first psychotic episode. Though studies on the clinical effectiveness of treating prodromal symptoms in people at UHR for psychosis exist, no review has exclusively and comprehensively evaluated the economic impact of UHR programs. Our objective was to systematically review the literature on economic evaluations of UHR programs.

METHODS

We searched the Cochrane, EMBASE, MEDLINE, and PsycInfo electronic databases, in addition to grey literature, from inception to March 2020 to identify economic evaluations of UHR programs. We included all cost and cost-effectiveness studies of interventions for people at UHR. The data were synthesized qualitatively, and a risk of bias assessment was performed.

RESULTS

Of the 1916 articles retrieved, six studies met our inclusion criteria. These included three cost analysis studies and three cost-effectiveness studies. Five studies were conducted from the health system perspective and the time horizon varied between six months and ten years. Only two reported quality-adjusted life-years (QALYs) as their outcome. Overall, all cost-effectiveness studies and one cost analysis suggested that UHR programs were cost-effective and cost saving, respectively. The risk of bias assessment suggested moderate levels of bias across all studies.

CONCLUSION

Economic evaluations of UHR programs varied in terms of outcomes and length of follow-up; however, most studies found them to be cost-effective. Future studies would benefit from long-term evaluations of UHR programs and consistent valuation of outcomes.