Abstract
Preterm birth (<37 weeks’ gestational age [GA]) occurs in 8% of live births in Canada. While advancements in neonatal medicine have led to increased survival in preterm births, infants born preterm continue to sustain short- and long-term health sequelae. There is paucity of large population studies evaluating childhood health care outcomes, including endocrine-related outcomes, in recent birth cohorts.
To evaluate the rates of endocrine conditions during the first 5 years of life in children born preterm and term.
The study cohort included liveborn infants at 22-44 weeks’ GA in British Columbia, Canada between 2004-2014. Follow-up data to December 2019 included linked health services use information from four BC provincial databases (perinatal database, hospitalizations, outpatient services, and outpatient prescriptions). Rates of outcomes were compared by GA at birth (37-44 weeks reference category) using robust Poisson regression.
There were 455,960 children included in this study with 42,820 (9.4%) born at <37 weeks GA. Results are summarized in Table 1 and Table 2. Compared to children born at 37-44 weeks’ gestations, infants born at 36 weeks’ gestation or younger have an increased rate of thyroid disorders between 0 months and 5 years (rate ratio [RR]: 1.45, 95% confidence interval [CI]: 0.78-2.43; RR: 1.83, 95% CI 1.51-2.20; RR: 1.41 95% CI 1.26-1.57 for 22-27 weeks, 28-33 weeks and 34-36 weeks GA, respectively). Similarly, infants born at 36 weeks’ gestation or younger have a higher rate of conditions in growth and development (RR: 3.05, 95% CI: 0.76-7.96; RR: 3.20, 95% CI 2.04-4.76; RR: 1.42 95% CI 1.02-1.94 for 22-27 weeks, 28-33 weeks and 34-36 weeks gestations, respectively) and bone health conditions (RR: 1.38, 95% CI: 1.27-1.49; RR: 1.04, 95% CI 1.00-1.08; RR: 1.05 95% CI 1.03-1.07 for 22-27 weeks, 28-33 weeks and 34-36 weeks gestations, respectively). There was no difference in rates of conditions related to glucose metabolism such as diabetes mellitus or hypoglycemia.
Children born preterm have increased rates of endocrine conditions by age 5. Disorders of thyroid, growth and development are increased in infants born preterm. Children born preterm have an increase rate of bone-related disorders, including those born late-preterm. These results provide useful prognostic information for follow-up care for preterm children and for healthcare resource planning. Furthermore, these results highlight areas of future research in endocrine health among preterm infants.
