Are there age‐related differences in the frequency of post‐reflux peristaltic waves during impedance‐pH monitoring?

OBJECTIVES: The post-reflux swallow-induced peristaltic wave (PSPW) reflects esophageal chemical clearance. Pediatric data on this parameter remain limited. The aim of this study was to evaluate the behavior of the PSPW in children of different ages. METHODS: We conducted a retrospective analysis of pediatric multichannel intraluminal pH/impedance, studies were performed for suspected gastroesophageal reflux (GER). We included those with a normal reflux index, symptom index <50%, symptom association probability <95% and a number of reflux episodes within normal parameters for age. Patients were divided into three groups according to their age: Group I (0-≤2 years), Group II (>2-≤10 years), and Group III (>10-≤18 years). The PSPW index was calculated manually. RESULTS: Two hundred and sixty-one studies were analyzed, 195 were included (median age 6.3 years, 54% female). Group I showed significantly more reflux events (38 vs. 26 and 32 in Groups II-III, p = 0.004) with predominance of non-acid reflux (p < 0.001) and greater proximal extent (p = 0.005). PSPW index was significantly lower in Group I (42.1%) compared to Groups II (52.6%) and III (50.0%) (p = 0.009). CONCLUSIONS: In this pediatric cohort, a higher number of gastroesophageal reflux episodes, a predominance of non-acid reflux and greater proximal extent were observed in infants ≤2 years, as well as reduced chemical clearance, which is reflected in a lower PSPW index compared to the other groups analyzed. Age-specific interpretation of PSPW could improve the evaluation of pediatric GER and therapeutic management.