Congenital anomalies and comorbidities in neonates with Down Syndrome.

Introduction: In Chile, Down syndrome has a prevalence of 2.5 in 1,000 live births. These patients present more congenital anomalies and comorbidities than the general population, increasing their hospitaliza tion rate.

Objective: To describe congenital anomalies and comorbidities of neonates with Down syndrome born and/or hospitalized between 2008 and 2018.

Patients and method: We conducted a retrospective review of patient's medical records born and/or hospitalized during their first 28 days of life between January 1st, 2008, and December 31st, 2018. For each patient, we recorded maternal age, familiar cases of Down Syndrome, pre and perinatal history, genetic study result, as well as age at admission, reason for hospitalization, comorbidities, length of stay, and death. Two patients that had more than 50% of incomplete medical records were excluded. We studied the associations between comorbidities, congenital anomalies, and death.

Results: 140 in 79,506 newborns (0.2%) were diagnosed at our center with Down Syndrome in their neonatal period. 24.7% were born preterm and 26.4% had low birth weight for gestational age. Morbidities and hospitalizations were present in 83.6% and 90%, of the study population, respectively. The main reason for hospitalization was polycythemia and the most frequent was hyperbilirubinemia. Four patients died (2.9%) and 70.7% presented at least one congenital anomaly, mainly heart disease. Median maternal age was 36 years and 57.1% of mothers were aged 35 or older.

Conclusions: This cohort of patients with Down Syndrome provides important information for the optimization of their perinatal management and follow-up.