The Timing and Factor of Ductus Arteriosus Closure in Infants with Down Syndrome Born at Term and Late-Preterm.

Delayed closure of the ductus arteriosus (DA) is not uncommon in infants with Down syndrome (DS). This retrospective study aimed to clarify the timing of DA closure in DS patients. A total of 101 DS patients born at ≥ 34 weeks' gestation hospitalized over the past 7 years were enrolled. None had received cyclooxygenase inhibitors. Eighty-two patients (81%) had spontaneous DA closure, with no significant difference in the rate of closure based on gestational age. Of these, spontaneous DA closure occurred within the first 3 days in 22%, between days 4-7 in 30%, between 1-2 weeks in 26%, between 2-3 weeks in 9%, and after 3 weeks in 13%. The median age at spontaneous DA closure was 7 days. The frequency of spontaneous DA closure was 67% in males and 26% in females (p = 0.001). The prevalence of the following conditions was compared between infants with and without spontaneous DA closure: persistent pulmonary hypertension (35% vs. 47%, p = 0.33), congenital heart disease (55% vs. 79%, p = 0.054), lymphatic dysplasia (7% vs. 16%, p = 0.36), congenital digestive tract disease (27% vs. 16%, p = 0.39), transient abnormal myelopoiesis (15% vs. 11%, p = 0.64), and hypothyroidism (13% vs. 26%, p = 0.175). DA ligation was performed in 20% of patients with CHD and 10% of those without (p = 0.67). Males were significantly more likely to have spontaneous DA closure than females. The timing of DA closure is often delayed in patients with DS, and the likelihood of spontaneous closure decreases after the first 3 weeks.