Effects on lung diseases reactive of transient tachypnea of the newborn in childhood

Objective: Transient tachypnea of the newborn (TTN) is one of the most commonly seen postnatal respiratory problems. Although it does not have same meaning in the asthma, bronchial hyper-reactivity (BHR) is most specific and important diagnostic feature of asthma since it is present in asthma patients at all ages. The BHR is more frequently seen patients with previous TTN. The relationship between TTN and BHR has been discussed in the literature. In this study, it was aimed to identify whether patients followed in neonatal intensive care unit with diagnosis of TTN had experienced reactive airway problems after one year of age and to evaluate relationship between TTN and reactive airway disorders such as asthma. Method: In this study, we retrospectively reviewed files of patient who were diagnosed as TTN and admitted to Neonatal Intensive Care Unit of Gaziosmanpaşa University, Medicine School between 01.05.2015 and 01.05.2018. For all patients, age, gestational age at birth, birth weight, length of stay in neonatal unit, history of antibiotic use during this period and ventilation need. In addition, 100 healthy children (aged 1-5 years) were included as controls. Overall, data regarding reactive airway disease were recorded in 150 patients and 100 controls via telephone interview. Results: During study period, 4777 patients were admitted to neonatal intensive care unit (NICU) including 3370 patients (70.5%) born via C/S and 1407 patients (29.5%) born via normal spontaneous vaginal delivery (NSVD). Among patients admitted, TTN incidence was 3.2%). Overall 160 cases with TTN were detected. The TTN was detected in 3.5% of patients born via C/S while in 2.3% of patients born via NSVD (p<0.064). Of 150 patients with TTN, 79 (52.6%) had history of at least one bronchiolitis. When bronchiolitis incidence was compared between patient and control groups, it was found that previous history of bronchiolitis was found in 52.6% of patient group vs. 44.0% of control group (p=0.179). Mean age at first bronchiolitis attack was found as 5.2±8.66 months in the patient group whereas 4.37±6.6 months in the control group (p<0.417). Mean gestation age was 37.13±1.84 weeks in the patient group and 38.28±1.32 weeks in the control group (p<0.001). Mean number of bronchiolitis attacks was 1.46±1.85 in the patient group vs. 1.07±1.53 in the control group (p<0.071). When daily bronchodilator need was compared, mean daily bronchodilator need was 2.69±3.33 in the patient group whereas 2.1±2.68 in the control group, indicating no significant difference (p<0.138. Mean number of hospitalization for bronchiolitis was found as 0.28±0.69 in the patient group whereas 0.07±0.29 in the control group (p<0.001). The frequency of systemic steroid use during attack was 16.0% in the patient group while 7.0% in the control group (p<0.048). In addition, prophylactic inhaler steroid use was higher in the patient group when compared to controls (p<0.006). Moreover, prophylactic montelukast use rate was significantly higher in the patient group than controls (p<0.012). Conclusion: It was seen that systemic steroid, inhaler steroid and montelukast use were significantly higher during reactive airway disease in patients with TTN. When TTN patient group was hospitalized, the rate of antibiotic use was higher than that of the control group. The hospitalization rate of TTN group was high due to bronchiolitis. With these results, it can be concluded that babies who were followed up with TTN may face a more frequent and heavier clinic with reactive airway problems later in life. Keywords: Transient tachypnea of the newborn, bronchial hyperreactivity, asthma.