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The effect of maternal smoking on respiratory and arousal patterns in preterm infants during sleep
Hemant Sawnani1, Tonya Jackson, Thomas Murphy
1Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA.
Insights
Maternal smoking during pregnancy increases obstructive apnea events in preterm infants. These infants also show a reduced arousal response to breathing pauses, potentially increasing their vulnerability.
Area of Science:
- Neonatal Medicine
- Respiratory Physiology
- Sleep Medicine
Background:
- Prenatal cigarette smoke exposure is linked to Sudden Infant Death Syndrome (SIDS).
- The impact of maternal smoking on infant apnea and arousal patterns, particularly in preterm infants, remains unclear.
Purpose of the Study:
- To investigate the effects of prenatal cigarette smoke exposure on apnea and arousal patterns in preterm infants.
Main Methods:
- Multichannel polysomnography was used to study 30 preterm infants.
- 16 infants had prenatal exposure to cigarette smoke (S group), and 14 were controls (C group).
- No significant differences in gestational or postconceptional age were observed between groups.
Main Results:
- The smoking group exhibited a significantly higher apneic index (28.6/hour vs. 13.2/hour), primarily due to obstructive events during active sleep.
- The arousal index was significantly lower in the smoking group (34.5/hour vs. 46.3/hour).
- A notable decrease in the percentage of arousal following respiratory events was observed in the smoking group (10.7% vs. 29.4%).
Conclusions:
- Prenatal exposure to cigarette smoke leads to increased obstructive apnea during active sleep in preterm infants.
- These infants may have a higher arousal threshold, indicating a potential vulnerability.
- Altered respiratory and arousal patterns suggest increased risk for preterm infants of smoking mothers.
Abstract:
Prenatal exposure to cigarette smoke is associated with an increased risk of sudden infant death syndrome. The effect of maternal smoking on apnea and arousal patterns in preterm infants is currently unknown. Multichannel polysomnographic studies were performed in preterm infants. Thirty infants were enrolled into the study: 16 exposed prenatally to cigarette smoke (S) and 14 control infants (C). There was no difference in the gestational and postconceptional ages at the time of study. Maternal smoking was associated with a significant increase in the apneic index in these infants (28.6 +/- 6.4/hour [S] vs. 13.2 +/- 3.9 [C]; p<0.05), and the difference was noted for obstructive events and only during active sleep. The arousal index was significantly decreased in the maternal smoking group (34.5 +/- 2.3/hour [S] vs. 46.3 +/- 5.6/hour [C]; p<0.05), with a specific decrease in percentage of arousal after respiratory events (10.7 +/- 2.1% [S] vs. 29.4 +/- 5.4% [C]; p<0.05). In conclusion, preterm infants exposed prenatally to cigarette smoke have increased respiratory events during active sleep, predominantly due to obstructive apnea, and possibly a higher arousal threshold during apneic events. These alterations in respiratory and arousal patterns in preterm infants born to smoking mothers may lead to significant vulnerability in this population.
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