Being born preterm is linked to a higher chance of death from birth through the third and fourth decades of life.
A recent study from Wake Forest University School of Medicine and The Hospital for Sick Children (SickKids) in Toronto suggests that being born preterm is tied to a greater risk of death from birth up until the third and fourth decades of life.
Published today online in JAMA Network Open, the study highlights this concerning issue.
Approximately 10% of all births around the globe are considered preterm, meaning they occur before 37 weeks of gestation. Preterm birth is the leading cause of infant death worldwide and the second leading cause of death in children under 5 years old.
“Gaining insight into the long-term effects of preterm birth can help us formulate prevention strategies and determine interventions to enhance the health of those born preterm,” explained Asma M. Ahmed, M.D., Ph.D., an assistant professor of epidemiology and prevention at Wake Forest University School of Medicine, a former post-doctoral fellow at SickKids, and the lead author of the study.
While most individuals born preterm do survive into adulthood, Ahmed noted that there is mounting evidence indicating a higher likelihood of mortality throughout their lives.
“We aimed to investigate whether those born preterm have a greater risk of both short-term and long-term death when compared to individuals born at full term,” Ahmed said.
This is the first comprehensive population-based analysis of preterm birth conducted in North America, where Ahmed and her team examined a cohort of nearly 5 million live births in Canada, of which 6.9% were preterm. The subjects were born between 1983 and 1996 and were followed until 2019, providing a follow-up duration between 23 and 36 years.
Preterm births were divided into categories based on gestational age: 24-27 weeks, 28-31 weeks, 32-33 weeks, and 34-36 weeks, and compared with full-term births that occurred between 37-41 weeks.
The findings revealed that preterm birth is correlated with a heightened risk of death across all ages up to 36 years, with the most significant risks observed during the neonatal period (0-11 months) and early childhood (1-5 years).
“We also discovered that the likelihood of mortality is increased as gestational age decreases, with those born before 28 weeks experiencing the greatest risks,” Ahmed noted.
The study also uncovered elevated mortality risks linked to various causes, such as respiratory, circulatory, and digestive disorders; diseases affecting the nervous system, endocrine system, and infections; cancers; and congenital defects.
“These results indicate that preterm birth should be acknowledged as a major risk factor for mortality,” Ahmed stated. “This risk persists into the third and fourth decades of life. While immediate neonatal care is vital, ongoing follow-up and monitoring for individuals born preterm are essential to help decrease these risks.”
Ahmed emphasized that further studies are crucial in different populations, particularly in low- and middle-income countries where the rates of preterm birth are notably high. She also pointed out the need for research examining the underlying factors that contribute to the increased mortality risk following preterm birth.
This research received support from the Canadian Institutes of Health Research grant No. 438541.
