Laryngopharyngeal reflux (LPR) as well as gastroesophageal reflux disease (GERD) occur as a result of reflux of gastric contents. The post-reflux swallow-induced peristaltic wave (PSPW) is an esophageal reflex that helps in the chemical clearance of gastric contents after reflux events.

PSPW index is a new parameter endorsed to determine the effectiveness of chemical clearance in GERD, but not in LPR. A study was conducted recently to evaluate chemical clearance in LPR and GERD by measuring PSPW indices in a consecutive series of patients.

Off-therapy impedance-pH tracings were analyzed for 187 patients clinically defined as LPR (n = 105) or GERD (n = 82) by the dominant symptom profile. Investigators assessed conventional impedance-pH measures and PSPW indices.

Mean PSPW index was 39.7% ±17.7% in the LPR group vs. 20.6% ±13.4% in the GERD group. Abnormally low PSPW index (<61%) was noted in around 81% patients in the LPR group, and 97.6% in the GERD group. Area under the ROC curve for PSPW index for diagnosing LPR was 0.83 (p < 0.001).

The investigators noted that PSPW was impaired in patients with LPR as well as GERD. This points to impaired chemical clearance after a reflux event in both the groups. The impairment in PSPW index was more in GERD.

PSPW index can help in the diagnosis of both LPR and GERD.

Source: Park JS, Van der Wall H, Falk GL. Post-reflux swallow-induced peristaltic wave is impaired in laryngopharyngeal and gastro-oesophageal reflux disease. Clin Physiol Funct Imaging. 2022 Jan;42(1):8-14.