A Thickened Formula Does Not Reduce Apneas Related to Gastroesophageal Reflux in Preterm Infants

Abstract

Background: Apnea of prematurity (AOP) occurs frequently in preterm infants and a variable proportion of AOP can be induced by gastroesophageal reflux (GER). Conservative treatment, including dietary modifications, should be the first-line approach for both GER and GER-related apneas in this population. Objectives: To evaluate the efficacy of a starch-thickened preterm formula (PF) in reducing the frequency of apneas related to GER. Methods: Preterm infants with AOP were studied by combined impedance and pH monitoring and polysomnography. The 6-hour study period included two feeds, one of a commercially available PF and one of the same formula thickened with amylopectin (TPF). GER indexes, apneas and GER-related apneas detected after TPF and PF feeds were compared by Wilcoxon signed-rank test. Results: 24 infants were studied. During 140 h of registration, 289 apneas (147 after TPF and 142 after PF; p = 0.876), and 861 GER episodes (400 after TPF and 461 after PF; p = 0.465) were recorded. No difference in the number of AOP was found between TPF and PF. A significant reduction in acid exposure was found after TPF; there was no influence on non-acid GER indexes. The frequency of GER-related apneas did not differ between TPF and PF. Conclusions: A formula thickened with amylopectin did not reduce the number of AOP or GER-related apneas. It reduced acid GER features but had no effect on non-acid GER indexes. Future research should focus on exploring different conservative strategies to treat GER-related apneas in preterm infants.

Pharmacological Therapy of Gastroesophageal Reflux in Preterm Infants

“…Moreover, as we have subsequently shown [30], the number of apneas is significantly higher after nonacid GER episodes, which prevail in the early postprandial period [31], confirming Wenzl's previous findings [32]. In accordance with these results, neither thickened formulas [33] nor the administration of sodium alginate [34] was found to improve the rate of apneas in symptomatic preterm infants. Eventually, a significant temporal association between cardiorespiratory events and GER, particularly remarkable among obstructive apneas and MII-GER, has been recently reported by Nunez et al [35] in a small cohort of both term and preterm infants.…”

Gastro-Oesophageal Reflux and Apnoea: Is There a Temporal Relationship?

“…There were, however, no significant differences in the frequency of apnoeas in the epochs either preceding or following a reflux event (but only 6 preterm infants were investigated). Another study, suggesting that GOR does not cause apnoea, concerned the lack of effectiveness of feed-thickening in reducing apnoeas [24]. Twenty-four infants with apnoea of prematurity underwent oesophageal pH, MII, and cardiorespiratory monitoring after alternating formula thickened with amylopectin with unmodified formula.…”

“…Twenty-four infants with apnoea of prematurity underwent oesophageal pH, MII, and cardiorespiratory monitoring after alternating formula thickened with amylopectin with unmodified formula. The feed thickener was effective in significantly reducing the oesophageal acid exposure, but there was no significant difference in the frequency of clinically relevant apnoea [24]. Indeed, an editorial on the above paper suggested that apnoea of prematurity should not be treated with anti-reflux medications unless clear data proves a causal relationship [25].…”

Apnea of prematurity: challenges and solutions

“…32 Also, thickened formulas do not seem to reduce acid or nonacid gastroesophageal reflux in preterm infants more than non-thickened formulas. 33 …”