Reducing Periconceptional Methylmercury Exposure: Cost-Utility Analysis for a Proposed Screening Program for Women Planning a Pregnancy in Ontario, Canada.

Abstract

BACKGROUND: The assessment of neurodevelopmental effects in children associated with prenatal methylmercury exposure, from contaminated fish and seafood in the maternal diet, has recently been strengthened by adjustment for the negative confounding resulting from co-exposure to beneficial polyunsaturated fatty acids (PUFAs). OBJECTIVES: To determine the cost effectiveness of a periconceptional screening program of blood mercury concentration for women planning to become pregnant in Ontario, Canada. Fish intake recommendations would be provided for those found to have blood mercury levels above the intervention threshold. METHODS: Analysis was conducted using a combined decision tree/Markov model to compare the proposed screening intervention with standard care from a societal perspective over a lifetime horizon. The national blood mercury distributions of women aged 20-49 reported in the Canadian Health Measures Survey from 2009-2011 were used to determine the cognitive deficits associated with prenatal methylmercury exposure for successful planned pregnancies. Outcomes modelled included the loss in quality of life and the remedial education costs. Value of information analysis was conducted to assess the underlying uncertainty around the model results and to identify which parameters contribute most to this uncertainty. RESULTS: The incremental cost per QALY gained for the proposed screening intervention was estimated to be $18,051 and the expected value for a willingness to pay of $50,000/QALY to be $0.61. CONCLUSIONS: Our findings suggest that the proposed periconceptional blood mercury screening program for women planning a pregnancy would be highly cost-effective from a societal perspective. The results of a value of information analysis confirm the robustness of the study's conclusions.