Ethnic Variability in Persistent Asthma After In Utero Tobacco Exposure

In a recently published study, faculty member Esteban Gonzalez Burchard, MD, fellow Sam Oh, PhD, MPH and their colleagues relate in utero secondhand smoke exposure to risk of severe asthma. There is a limited number of studies comparing the effects of in utero and postnatal tobacco smoke exposure on asthma severity, and data are even more sparse for minority populations. For these reaons, the authors sought to examine these effects in Latinos and African Americans recruited in two studies: the Genetics of Asthma in Latino Americans (GALA) study and the Study of African Americans: Asthma, Genes and Environments (SAGE). Identification of such effects in minority populations is particularly important because these are the fastest growing populations in the United States. These populations are also disproportionately affected by asthma.

The study’s results indicate that maternal smoking during pregnancy is strongly associated with persistent asthma in a sample of African American, Puerto Rican, and Mexican pediatric asthma patients.  The odds of in utero exposure to tobacco smoke were 3.6 times as likely among persistent asthmatics than among intermittent asthmatics.  The high prevalence of maternal smoking during pregnancy, along with the reported 2009 overall rates of cigarette use of 19.2% for African American women and 9.8% for Hispanic women, have important consequences for public health.

The results indicate that a relatively brief (nine-month) period of tobacco smoke exposure during a crucial period of prenatal pulmonary development has significant consequences in the subsequent risk for persistent asthma and asthma-related outcomes. These effects are measurable at least 8 years post-exposure.  This observation lends deeper insight into the correlation between tobacco smoke exposure and asthma, and will hopefully encourage better translation of research on effective smoking prevention and cessation interventions, particularly among women during pregnancy.

To access the full paper, please click here