Children of a parent with alcohol or drug use disorder have a greater risk of intellectual disability, even if the problem only lies with the father, researchers from Karolinska Institutet in Sweden report.
The findings, published in the journal eClinicalMedicine, emphasize the need for preventive measures to address substance use disorders in both mothers and fathers.
ALL FORMS OF SUBSTANCE ABUSE
Traditionally, the focus of preventive measures has primarily cantered on maternal alcohol consumption during pregnancy. However, this study underscores that all forms of substance abuse, regardless of the parent’s gender and whether it occurs during or outside of pregnancy, can contribute to the risk of intellectual disabilities in offspring.
The study, based on extensive data from Swedish registries spanning from 1978 to 2002, analyzed nearly two million births and their parental histories. Key findings revealed that children born to parents without substance use disorders had a 1.2% incidence of intellectual disability. In contrast, those born to parents with diagnoses related to substance use disorders (alcohol or drug abuse) exhibited a higher incidence, at 3%.
Importantly, the study noted that the risk was significantly greater when the parent received a substance use disorder diagnosis before or during pregnancy, as opposed to after birth. Such a diagnosis before birth was associated with more than a twofold increase in the risk of intellectual disability in the child, irrespective of whether it was the mother or father with the diagnosis. The correlation remained statistically significant even after adjusting for socioeconomic factors and parental psychiatric comorbidity.
While the exact mechanisms behind these findings require further investigation, the researchers suggest that a combination of genetic and environmental factors, including the adverse effects of substance abuse on foetal development, may play a role.
IMPROVED DIAGNOSES
Dr. Lotfi Khemiri, a researcher at the Karolinska Institutet, hopes that these results will inform preventive efforts and lead to improved diagnoses and timely interventions for children with intellectual disabilities and parents in need of substance use disorder treatment.
Notably, the study also highlighted that alcohol-related problems during pregnancy presented a particularly high risk, with the likelihood of intellectual disabilities being five to three times higher, depending on whether it was the mother or father with the alcohol use disorder diagnosis.
