Increased mortality in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Context: Reports on mortality in patients with congenital adrenal hyperplasia (CAH) are lacking.

Objective: This study sought to study mortality and causes of death in CAH.

Design, Setting, And Participants: We studied patients with CAH (21-hydroxylase deficiency, n = 588; CYP21A2 mutations known, >80%), and compared them with controls (n = 58 800). Data were derived through linkage of national population-based registers.

Main Outcome Measures: Mortality and causes of death.

Results: Mean age of death was 41.2 ± 26.9 years in patients with CAH and 47.7 ± 27.7 years in controls (P < .001). Among patients with CAH, 23 (3.9%) had deceased compared with 942 (1.6%) of controls. The hazard ratio (and 95% confidence interval) of death was 2.3 (1.2-4.3) in CAH males and 3.5 (2.0-6.0) in CAH females. Including only patients born 1952-2009, gave similar total results but only patients with salt wasting (SW) or with unclear phenotype had an increased mortality. The causes of death in patients with CAH were adrenal crisis (42%), cardiovascular (32%), cancer (16%), and suicide (10%). There were seven additional deaths in CAH individuals with incomplete or reused personal identification number that could not be analyzed using linkage of registers. Of the latter, all except one were deceased before the introduction of neonatal screening in 1986, and most of them in the first weeks of life, probably in an adrenal crisis.

Conclusions: CAH is a potentially lethal condition and was associated with excess mortality due to adrenal crisis. The SW phenotype also seemed to have worse outcome in children and adults due to adrenal crisis and not only before the introduction of neonatal screening.