A case-control study on association between antenatal exposure to magnesium sulfate and patent ductus arteriosus in preterm infants

Abstract

Objective To identify the association between antenatal exposure to magnesium sulfate and patent ductus arteriosus（PDA） in preterm infants. Methods A 1 ： 1 case-control study was conducted on 93 preterm infants with PDA and 93 cases of matched controls without PDA hospitalized in our neonatal intensive care unit between January 2008 and December 2009. Information on antenatal exposure to magnesium sulfate, neonatal birth weight and other perinatal factors was collected and analyzed with univariate analysis, multivariate Logistic regression analysis. Results There were 51 preterm infants exposed to magnesium sulfate antenatally in PDA group and 34 infants in controls. The median （P25-P75） level of neonatal serum magnesium in PDA cases was 0.98 mmol/L （0.92-1.32 mmol/L） ,significantly higher than that in controls [0.90 mmol/L（0. 82-1. 09） mmol/L] （Z = 3.56, P=0.00）. Logistic regression analysis showed that PDA in preterm infants was significantly associated with antenatal magnesium sulfate exposure（OR=2. 646,95 %CI： 1. 356-5. 163, P=0.004）, fetal distress （OR= 7. 189, 95% CI：1.209-42.756, P=0.030）, neonatal birth weight （OR = 1. 842,95 % CI ： 1. 087-3. 438, P = 0. 049 ）, respiratory failure （OR = 3. 499,95 % CI ： 1.256- 9. 752, P=0. 017）and postnatal oxygen inhalation （OR=O. 482,95% CI：0. 233-0. 999, P=0. 045）. Also, a significant positive correlation was found between PDA and the dose of magnesium sulfate and the concentrations of serum magnesium in preterm infants （Хtrend^ 2= 7.41, P= 0. 007 ;Хtrend^ 2 = 12. 13, P= 0. 000）. Conclusions Antenatal exposure to magnesium sulfate might increase the risk of PDA in preterm infants. Key words: Infant, premature; Ductus arteriosus, patent; Magnesium sulfate