Cystic fibrosis-related deaths in infancy and the effect of newborn screening

Although newborn screening for cystic fibrosis (CF) is widely advocated, hard evidence in its favor is difficult to obtain, partly because of a dramatically improved life expectancy. Between 1985–l989 infants, born in Wales and the West Midlands were randomized to newborn CF screening by heel‐prick immunoreactive trypsin (IRT) measurement or diagnosis by clinical presentation. Eligible children with CF who died in the first 5 years of life were identified from the local pediatricians and from the National UK CF Survey. In all, 230,076 infants were randomized to be screened, while 234,510 were unscreened. One hundred seventy‐six CF children were identified, of whom 7 died in the first 5 years of life, 3 having presented with meconium ileus. Median age of diagnosis in the screened group was 8 weeks. On an intention to treat analysis, all 4 nonmeconium ileus‐related deaths occurred in the unscreened group (Fisher's exact test, P