Frequency and Characteristics of Hypothyroidism in Neonatal Intensive Care Unit Patients in a Tertiary Care Hospital

Abstract

Objective: To Investigate frequency, clinical and laboratory profiles of hypothyroidism in neonates admitted to the Neonatal Intensive Care Unit (NICU) in a tertiary care hospital.

Methodology: This Prospective, cross-sectional study Neonatology Department, Fatima Memorial Hospital, Lahore, from July 2024 to December 2024. A total of 200 neonates admitted in NICU were included using consecutive non-random sampling. Thyroid function was assessed through serum free T4 and TSH levels, with hypothyroidism diagnosed based on low free T4 or elevated TSH levels and clinical symptoms. Data were analyzed using SPSS 25.0, with statistical significance set at p < 0.05.

Results: Among 200 neonates, 23 (11.5%) were diagnosed with congenital hypothyroidism (CH), while 33 (16.5%) exhibited subclinical hypothyroidism. Low free T4 levels were observed in 21 (10.5%) neonates, and high TSH levels in 36 (18%). Feeding intolerance was the most common clinical symptom noted in 52.5% of cases. Significant maternal factors associated with CH included gestational illness (p = 0.008), antenatal steroid use (p = 0.003), and multiple gestations (p = 0.027). Predominant neonatal risk factors were preterm birth (p < 0.001), cesarean delivery (p = 0.016), and intrauterine growth restriction (IUGR) (p = 0.044). The prevalence of hypothyroidism was higher in preterm (p <0.001) and low-birth-weight neonates (p = 0.191), highlighting the vulnerability of this subgroup.

Conclusion: Congenital hypothyroidism is prevalent in NICU patients, particularly those born preterm or with low birth weight. Maternal and neonatal factors significantly influence the risk.