Full title: Cost-effectiveness of the newborn screening of congenital adrenal hyperplasia
Authors: Castilla I, Vallejo-Torres L, Rica-Echevarría I, Rodríguez-Sánchez A, Dulín-Íñiguez E, Espada M, Rausell D, Valcárcel-Nazco C, Cuéllar-Pompa L, Serrano-Aguilar P.
Contact person: Iván Castilla Rodríguez (ivan.castillarodriguez@sescs.es)
Summary
Introduction
The Ministry of Health, Social Services and Equality aims to reduce the inequalities in the newborn screening programmes offered in the different regions in Spain. After the decision to increase to seven the number of conditions included in the early detection programme offered nationally, decisions makers are now considering the inclusion of three additional conditions, including congenital adrenal hyperplasia. Newborn screening programmes have to meet a series of requirements, including providing evidence on the cost-effectiveness of the programme, by comparing the costs and health outcomes of early detection to those related to the clinical diagnosis.
Objectives
To evaluate the cost-effectiveness of incorporating congenital adrenal hyperplasia to the series of conditions being screened in the newborn screening programme in Spain, and to determine the budget impact of its implementation.
Method
We developed a cost-effectiveness model that compared two options: including congenital adrenal hyperplasia to the diseases screened in the national screening programme and to no include this condition in the early detection programme and diagnose the condition by clinical diagnosis. The model takes into account to the life expectancy of the newborns, capturing the impact on the long term of the early detection. The perspective of the analysis was that of the National Health Service in Spain, expressing the costs in 2013 prices. We estimated the cost related to the screening programme including screening tests, confirmation tests, as well as treatment and follow up costs of those detected by the programme. These costs were compared with those related to the clinical diagnosis of the condition. The differences in the costs were then compared with the difference on the effectiveness. Effectiveness was measured using life expectancy, by taking into account deaths avoided by screening, and expressed as life-years gained (LYG). Health outcomes and costs were discounted at a 3% rate. We undertook a one-way sensitivity analysis on those parameters with the highest impact on the results and those surrounded by the highest uncertainty, and a probabilistic sensitivity analysis using Monte Carlo simulation.
Results
According to the results of this study, newborn screening for congenital adrenal hyperplasia is more costly and more effective than clinical detection. For a lifetime horizon, the incremental costs per newborn are € 1.71, and the incremental life years per newborn are 0.00022, giving an incremental cost effectiveness ratio of € 7,899/LYG, which is below € 30,000/LYG, i.e. the usual threshold used in Spain. The sensitivity analysis estimated that newborn screening for congenital adrenal hyperplasia is cost-effective with a probability of 88.5% and for a willingness to pay per life year gain of € 30,000/LYG. Nevertheless, there is a high uncertainty surrounding the sensitivity of the clinical detection (especially in the salt-wasting form).
Conclusions
According to the available evidence when developing this report, the introduction of neonatal screening for congenital adrenal hyperplasia would be cost effective for a willingness to pay € 30,000/LYG, assuming a clinical sensitivity for the salt-wasting form of 85% when screening is not available. Nevertheless, these results should be considered carefully due to the high uncertainty surrounding the estimation of the clinical sensitivity.