Oligohydramnios increases the risk of respiratory hospitalization in childhood: a population-based study

Abstract

Background: Pulmonary hypoplasia is associated with reduced lung function in infancy. The aim of this study was to evaluate the hypothesis that children exposed to oligohydramnios display an increased risk of hospitalization for respiratory illness by using a population-based matched-cohort design. Methods: We used three nationwide population-based data sets to identify 5,228 women who gave birth during 2004 to 2007 and were diagnosed with oligohydramnios during the third trimester of pregnancy. A cohort of 20,912 unaffected pregnant women was matched with these cases, according to neonatal sex and gestational age, maternal age and education, and level of prenatal care. Respiratory hospitalization and respiratory failure were defined using discharge diagnostic codes. results: Oligohydramnios-exposed children had an 8% higher incidence rate of respiratory hospitalization and an 80% higher incidence rate of respiratory failure, compared with children without oligohydramnios exposure. This risk remained after adjusting for all potential risk factors. Cox regression analyses indicated that the adjusted hazard ratios of respiratory hospitalization and respiratory failure were 1.07 (95% confidence interval (CI): 1.01-1.15; P = 0.030) and 2.20 (95% CI: 1.26-3.84; P = 0.005), respectively. conclusion: Children exposed to oligohydramnios during the third trimester of pregnancy display an increased risk of hospitalization for respiratory illness. P ulmonary hypoplasia is uncommon in the perinatal period but is a critical cause of death in newborn infants. Oligohydramnios is one of the abnormalities most commonly associated with pulmonary hypoplasia (1). Lung growth is influenced by physical factors such as the intrauterine space, lung liquid volume and pressure, and breathing movements. For lungs to develop, the physical space in the fetal thorax must be adequate, and amniotic fluid must be drawn into the lungs through fetal breathing movements, leading to their distension. Physical forces play vital roles in regulating fetal lung growth and maturation (2,3). During lung development, the main physical force experienced by the lung is stretching induced by breathing movements and lung fluid in the air spaces (4). Oligohydramnios reduces the intrathoracic cavity size, disrupting fetal lung growth and leading to the development of pulmonary hypoplasia (5,6).Oligohydramnios is a critical factor affecting short-and long-term clinical prognoses. In a study by Lindner et al. (7), neonates exposed to oligohydramnios experienced shortterm respiratory morbidity (including high ventilator settings, increased incidence of hypoxemia and hypercapnia, and pulmonary hypertension) and tended to experience more air leaks than did healthy neonates. Pulmonary hypoplasia is also associated with reduced lung function in infancy (8). Previous studies have reported the short-term perinatal outcomes of pregnancies complicated by oligohydramnios (9-12). A small case-control study found that infants born following the preterm rupture of membranes a...

Development of the lung

“…These conditions are encountered due to a fetal exposure to an oligohydramnios. It causes pulmonary hypoplasia and an 80% higher risk of respiratory failure as compared to unaffected fetuses (Chien et al 2014 ). An oligohydramnios is often part of an autosomal recessive polycystic kidney disease.…”

Isolated oligohydramnios and long-term neurological morbidity of the offspring

“…17,18 However, little has been reported regarding long-term outcomes in children born after pregnancies complicated by IO, especially when assessed as an independent variable. Long-term complications of IO were previously reported by Chien et al 19 , in which an increased risk of respiratory-related hospitalizations was suggested in IO exposed offspring. In addition, an increased risk for cerebral palsy (CP) or even death at 18 months was described by Sasahara et al, 20 though, unlike our study, this study was designed for preterm small for gestational age infants born with oligohydramnios.…”

Pulmonary Hypoplasia Induced by Oligohydramnios: Findings from Animal Models and a Population-Based Study

“…48 However, the long-term effects of oligohydramnios on the respiratory system are unknown. In a retrospective cohort study, Chien et al 49 observed that oligohydramnios-exposed children had an 8% higher incidence rate of respiratory hospitalization (ICD-9-CM: 493, 494, 496, 512, 518, 786.00, 786.05, 786.07, 786.09, 786.1e786.4, 799.02, or 799.1, 466, 480e487, 490, 491, 510, or 513, 786) and an 80% higher incidence rate for respiratory failure (ICD-9-CM: 96.70, 96.71, or 96.72) compared with children without oligohydramnios exposure. This risk remained following adjustment for neonatal characteristics, parental demographics, insurance eligibility group, urbanization level of insurance registration area, level of prenatal care, and maternal risk factors.…”

“…However, the underlying mechanism by which oligohydramnios alters the respiratory system and its effects on long-term respiratory outcomes remain unclear. According to a series of studies with an established animal model 29,34,37,42 and a population-based study, 49 a schematic diagram illustrating prenatal exposure to oligohydramnios and the implications for subsequent respiratory disease is provided in Figure 2.…”