Children with grandmothers who smoke during pregnancy at risk for asthma

Swedish children whose grandmothers smoked during pregnancy were at an increased risk for asthma, regardless of whether or not their mother was a smoker, according to data presented at the European Respiratory Society’s International Congress in Amsterdam.

“We found that smoking in previous generations can influence the risk of asthma in subsequent generations,” Caroline J. Lodge, PhD, research fellow at the University of Melbourne, Australia, said in a news release. “This may also be important in the transmission of other exposures and diseases.”

The researchers analyzed data from the Swedish Registry, including 44,583 grandmothers who gave birth to 46,197 mothers between 1982 and 1986. Those daughters subsequently gave birth to 66,271 children between 1996 and 2000. Exposure to smoking was recorded for grandchildren at 10 to 12 weeks’ gestational age, from both mothers and grandmothers. The researchers tracked later development of asthma in grandchildren by analyzing any purchases of inhaled steroids from 2005 to 2013.

Study data showed that grandmothers who smoked during early pregnancy were associated with an increased risk for asthma in grandchildren aged 1 to 6 years, with the greatest risk among children aged 2 to 3 years (OR = 1.22; 95% CI, 0.99-1.31). The granchildren had an increased risk for asthma that ranged from 10% to 22%.

“For us to understand more about the asthma epidemic, we require a greater understanding of how harmful exposures over your lifetime may influence the disease risks of generations to come,” Lodge said in the release. “Additionally, researchers in this area need to be aware, when interpreting the asthma risk from current exposures and genetic predisposition, that individuals may carry an inherited, nongenetic, risk from exposures in previous generation. This knowledge will help to clarify the findings concerning current risk factors in asthma research.”

Reference:
Lodge CJ, et al. Oral Abstract 4762. Presented at: European Respiratory Society International Congress; Sept. 26-30, 2015; Amsterdam, Netherlands.

Disclosure: The researchers report no relevant financial disclosures.