No large-scale studies of the incidence or disease severity of cystic fibrosis (CF) in black patients have been reported to date. In this study, the CF Foundation National Patient Registry was used to establish new incidence figures and to compare the clinical status of U.S. black (n = 601) and white patients (n = 17,755) with CE Results indicate that the incidence of CF is approximately 1 in 3,200 white and 1 in 15,000 black live births in the United States. Black patients with CF are currently, and were at diagnosis, younger and have poorer nutritional status and pulmonary function than white patients with CF. Fewer have meconium ileus, but more have distal intestinal obstruction syndrome. To control for genotype, each black deltaF508 homozygote (n = 47) was compared with four age- and sex-matched white deltaF508 homozygotes. Only the difference in nutritional status remained. The deltaF508 mutation is associated with higher levels of meconium ileus than other genotypes, independent of race. In conclusion, the clinical manifestations of CF are similar in black and white patients except for poorer nutritional status in black patients, which appears to be independent of age and genotype.

Department of Pediatrics and Center for Medical Genetics Johns Hopkins University School of Medicine Baltimore Maryland 21287 3914 USA