How then to explain the negative findings of Kuribayashi et al? One need only examine Table 1 of their treatise to resolve this seeming contradiction. The median number of reflux events during sleep among the 20 patients with GERD (with or without OSA) studied (one event) was no different than the number of reflux events observed in the 15 control subjects (two events) or in the subjects with OSA and without GERD (one event). Evidently, for whatever reason, these patients had minimal reflux during the night of the study. Further suggesting that they had mild disease, many of them were defined as patients with GERD on the basis of exhibiting symptomatic response to therapy rather than by pH monitoring, none of them had a fixed hiatus hernia, and as a group, their mean BMI was no different than for the control population. Contrast this to the patients studied by Tawk et al,7 who were awakening from sleep with heartburn at least once per week, had a mean BMI of 35.1, and had a baseline esophageal acid exposure time of 12.4%, making it a virtual certainty that most if not all of them had a hiatal hernia. Quite simply, the two studies were looking at dissimilar GERD populations.