How many deaths can be prevented by newborn screening for congenital adrenal hyperplasia?

BACKGROUND/AIMS Congenital adrenal hyperplasia (CAH) is increasingly being included in newborn screening programs. Screening can prevent neonatal mortality in children with salt-wasting CAH, but the number of deaths prevented is not known. Cost-effectiveness analyses of screening require estimates of the probability of mortality in CAH. METHODS We reviewed the literature to identify cohort studies of children with CAH ascertained clinically in the absence of screening. We abstracted the numbers of infant deaths attributable to CAH. We also addressed sex ratios among children with clinically detected CAH and the contribution of ascertainment bias to unbalanced ratios. RESULTS The evidence suggests a probability of infant death due to adrenal crises in salt-wasting CAH of 4% or less in contemporary advanced economies without screening for CAH. This is lower than previous estimates, although the rate of mortality could be considerably higher in populations with limited clinical awareness or access. CONCLUSION Although screening for CAH is conducted in a number of countries, further research is still needed to provide reliable estimates on the numbers of prevented deaths, along with evidence-based assessments of the potential benefits, harms, and costs of screening.