Family history of asthma in infants with bronchopulmonary dysplasia.

The role of genetic or familial factors in the development of bronchopulmonary dysplasia (BPD) has not been evaluated. Detailed histories concerning asthma, allergy, and other lung diseases were obtained on first and second degree relatives of 17 infants with BPD, and 21 infants who had hyaline membrane disease but who did not develop BPD (HMD group). All infants in the BPD and HMD groups had hyaline membrane disease requiring assisted ventilation and greater than 50% inspired oxygen in the first five days of life. The diagnosis of HMD and BPD were made on radiographic and clinical criteria. Of the 17 infants with BPD, 13 had first or second degree relatives with physician-diagnosed asthma, compared to seven of 21 in the HMD group (P less than .01). In addition, a significantly greater number of relatives of BPD infants (P less than .005) had been hospitalized for their asthma as compared to HMD relatives. There were no differences between the groups for allergic rhinitis, eczema, bronchitis, emphysema, chronic cough, smoking, or wheezing with respiratory illnesses. These results suggest the possibility that airways with a genetic predisposition for reactivity may become highly reactive following neonatal lung disorders and their treatment. These irritable airways may then contribute to the development, or progression, or both of BPD.