Smoking During Pregnancy Linked to Severe Asthma
Exposure to tobacco smoke before birth causes severe asthma in many children, even without later exposure, according to a multicenter study led by researchers at the University of California, San Francisco (UCSF).
This study tapped into two previous, large-scale research projects that together studied 295 children with asthma, aged 8 to 16 years, with Mexican, Puerto Rican and African American heritage. 9.2 percent of these children had mothers who reported smoking while pregnant. Overall, 11 percent of the children with severe asthma were exposed before birth versus 6 percent of children with mild asthma.
Prenatal exposure was also associated with three times the number of daily and night-time asthma symptoms later in the child's life, as well as nearly four times the number of asthma-related emergency room visits, even when the researchers controlled for other risk factors, such as current tobacco exposure, ethnicity and allergies.
The effects of smoking during pregnancy far outweighed exposure to cigarette smoke during the first two years of life, or even current exposure to smoke.
Tobacco exposure had been clearly linked to childhood asthma before, but previous studies were inconclusive on the role of prenatal exposure in the severity of attacks, particularly among the racial and ethnic populations with the highest incidence of asthma. Smoking during pregnancy has been known to have many effects on the fetus and later childhood, including low birth weight, sudden infant death and impaired lung function.
Esteban Burchad, M.D., Clinical Professor of Bioengineering and Therapeutic Sciences and Medicine at UCSF studies asthma genetics. Dr. Burchad said the current study points to genetic changes that occur long before a child takes its first breath and that something happens in the womb that can have a dramatic effect years later.
Sam Oh, PhD, MPH, one of the lead authors on this study at UCSF, said that a parallel study through the tobacco center found that mothers who did not finish school were the most likely to smoke during pregnancy. He further states that the burden on the family of having someone with persistent asthma can be substantial, with the heaviest toll on low-income families, who are at highest risk of asthma, but least able to miss work to care for a child with asthma.
Smoking during pregnancy is not the only factor that leads to asthma, but it was significant even when other factors were taken into account, including allergies, history of family asthma, age, sex and birth site across ethnic groups. An estimated 13.8 percent of American women smoke during pregnancy, according to the U.S. Pregnancy Risk Assessment Monitoring system. The findings in this study give a strong incentive to reduce that to zero.
► Please send any comments or suggestions for this and future Newsletters to us here. Your input is valued and appreciated. Please feel free to distribute this Newsletter to others who may be interested. Tobacco Free Northeast PA at Burn Prevention Network is funded by a grant from the PA Department of Health Division of Tobacco Prevention and Control Program to manage tobacco programming in the 10 counties of the Northeast Health District which includes: Carbon, Lackawanna, Lehigh, Luzerne, Monroe, Northampton, Pike, Susquehanna, Wayne, and Wyoming. Tobacco programming in the District is comprised of teen prevention and advocacy, tobacco free policies and tobacco treatment programs. Please visit our website at www.tobaccofreene.com or call 1-866-974-QUIT (7848) for minformation. Tobacco Free Northeast PA does not discriminate with regard to race, color, religion, national origin, ancestry or place of birth, sex, sexual orientation, gender identity or expression, age, handicap or disability
