Maternal use of illicit drugs, tobacco or alcohol and the risk of childhood cancer before 6 years of age

Drug Alcohol Depend. 2019 Jul 1;200:133-138. doi: 10.1016/j.drugalcdep.2019.03.008. Epub 2019 Apr 30.

Abstract

Background: Previous studies provide conflicting evidence of a link between maternal substance use and risk of childhood cancer.

Methods: We analyzed a cohort of 785,438 newborns in Quebec (2006-2016). We identified infants whose mothers had problematic illicit drug, tobacco, or alcohol use before or during pregnancy. The primary outcomes were childhood hematopoietic cancer or solid tumors within 0-5 years of age. Using Cox proportional hazards models, we computed hazard ratios (HR) and 95% confidence intervals (CI) for the association between maternal substance use and childhood cancer, adjusted for potential confounders.

Results: A total of 925 cases of cancer occurred during 3.5 million person-years of follow-up. Children exposed to any maternal substance use had marginally elevated cancer incidence rates compared with unexposed children (29.4 vs. 26.1 per 100,000 person-years). Maternal illicit drug use was associated with the risk of acute lymphoblastic leukemia (HR 1.63, 95% CI 0.79-3.36) and fibrosarcoma (HR 2.11, 95% CI 0.86-5.16). Maternal tobacco use was associated with acute myeloid leukemia (HR 2.01, 95% CI 0.72-5.60) and fibrosarcoma (HR 2.13, 95% CI 1.05-4.32), but a weak association with neuroblastoma (HR 1.21, 95% CI 0.61-2.40) and renal tumors (HR 1.14, 95% CI 0.42-3.13) also appeared to be present.

Conclusions: We found a potential association between maternal substance use and certain types of early childhood cancer. Although effects were modest, maternal substance use may contribute to some types of childhood cancer, especially leukemia and fibrosarcoma.

Keywords: Childhood cancer; Maternal substance use; Pediatric cancer risk factors; Population-based cohort; Prenatal exposure.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alcohol Drinking / epidemiology*
  • Child, Preschool
  • Cohort Studies
  • Female
  • Humans
  • Illicit Drugs / adverse effects*
  • Infant
  • Infant, Newborn
  • Male
  • Neoplasms / diagnosis
  • Neoplasms / epidemiology*
  • Pregnancy
  • Pregnancy Complications / diagnosis
  • Pregnancy Complications / epidemiology*
  • Prenatal Exposure Delayed Effects / diagnosis
  • Prenatal Exposure Delayed Effects / epidemiology*
  • Quebec / epidemiology
  • Risk Factors
  • Substance-Related Disorders / diagnosis
  • Substance-Related Disorders / epidemiology
  • Tobacco Use / epidemiology*

Substances

  • Illicit Drugs