Am J Epidemiol. 2024 Apr 6:kwae038. doi: 10.1093/aje/kwae038. Online ahead of print.

ABSTRACT

Animal studies have shown that exposure to cigarette smoke during pregnancy can induce neurobehavioral anomalies in multiple subsequent generations. However, little work has examined such effects in humans. We examined the risk of grandchild autism spectrum disorder (ASD) in association with grandmother smoking during pregnancy, using data from 53,562 mothers and grandmothers, and 120,267 grandchildren in the Nurses’ Health Study II using nurse reporting in 1999 of her mother’s smoking. Grandchildren’s ASD diagnoses were reported by the mothers in 2005 and 2009. Among grandmothers, 13,383 (25.0%) smoked during pregnancy, and 509 (0.4%) grandchildren were diagnosed with ASD. The adjusted odds ratio (aOR) of ASD for grandmother smoking during pregnancy was 1.52 (95% confidence limit [CI]: 1.06, 2.20). Results were similar with direct grandmother reporting in 2001 of her smoking during pregnancy from the Nurses’ Mothers Cohort Study subgroup (n=22,167 grandmothers, 49,917 grandchildren) and stronger among grandmothers who smoked ≥15 cigarettes per day during pregnancy (aOR=1.93; 95% CI: 1.10, 3.40; n=1,895 grandmothers, 4,212 grandchildren). Results were similar when adjusted for mother’s smoking during pregnancy. There was no association with grandfather’s smoking as reported by the grandmother. Our results suggest potential persistent impact of gestational exposure to environmental insults across three generations.

PMID:38583942 | DOI:10.1093/aje/kwae038