Using newborns as a long-term indicator of maternal heart health may seem like a far-fetched idea, but a new study by researchers from McGill University and the University of Montreal Hospital Research Center has revealed that women who give birth to infants with congenital heart defects may have an increased risk of cardiovascular hospitalizations later in life. The results of the new study were published today in the journal Trafficin an article entitled “Long-term risk of cardiovascular disease in women who have had infants with heart defects”.
The new study, which involved more than one million women, is the first to show that congenital heart defects in newborns may be a marker of an increased risk of their mothers developing heart problems, including a heart attack and heart failure, years after the pregnancy.
“Caring for infants with severe heart defects is associated with psychosocial and financial stress, which may increase the mothers’ long-term risk of cardiovascular disease,” said study lead researcher Nathalie Auger. , MD, epidemiologist at the Center de recherche du Center hospitalier de l’Université de Montréal. .
The researchers analyzed data on women who gave birth between 1989 and 2013 in Quebec, Canada, and who had critical, non-critical or no heart defects. They followed the women up to 25 years after pregnancy for hospitalizations related to cardiovascular disease, including heart attacks, heart failure, atherosclerotic disorders and heart transplants.
“We studied a cohort of 1,084,251…and identified women whose infants had critical, non-critical, or no heart defects, and followed the women over time for future hospitalizations for cardiovascular disease, with follow-up extending up to 25 years post-pregnancy,” the authors wrote. “We calculated the incidence of cardiovascular hospitalizations per 1000 person-years and used Cox proportional hazards regression to estimate hazard ratios and 95% confidence intervals (CIs) for the association between childhood heart defects and the risk of maternal cardiovascular hospitalization. Models were adjusted for age, parity, preeclampsia, comorbidity, material deprivation, and period.
When the research team compared mothers of infants without congenital heart defects to those with heart problems, they found a 43% higher risk of cardiovascular hospitalization in women whose offspring had critical heart defects. Additionally, scientists found a 24% higher risk of cardiovascular hospitalization in women whose infants had non-critical malformations.
The relationship between heart defects in infants and post-pregnancy cardiovascular disease in their mothers is currently unclear, the study notes, and a genetic component cannot be ruled out. Additionally, given that 85% of infants with heart defects now survive beyond adolescence, the psychosocial impact of congenital heart disease on caregivers may have a long-term cumulative effect.
The researchers believe the study offers these mothers the opportunity to benefit from early prevention strategies and counseling to reduce their risk of cardiovascular disease, the leading cause of death in women. However, some limitations of the research include that the women were young at the start of the study, so for many the 25-year follow-up did not extend beyond menopause, which excluded the most at risk of cardiovascular disease. Also, because the researchers used existing medical data, they didn’t have detailed information about women’s risk factors, such as body weight and smoking status. These are important points that should be considered in future studies, the researchers noted.
Yet healthcare providers, like obstetricians, who treat and follow mothers in the early stages of caring for children with heart defects can help women understand and minimize their risk.
“These physicians are in the best position to educate women about this possibility, the increased risk of heart disease, and to provide recommendations to target other risk factors such as smoking, obesity, and physical activity,” said concluded Dr. Auger.