Esophageal Acidification During Nocturnal Acid-breakthrough with Ilaprazole Versus Omeprazole in Gastroesophageal Reflux Disease

BACKGROUND/AIMS: Though nocturnal acid-breakthrough (NAB) is common in gastroesophageal reflux disease (GERD) patients, its clinical importance results from esophageal acidification, which has been shown to be uncommon. Ilaprazole, a long-acting proton pump inhibitor, may cause NAB infrequently. Accordingly, we studied prospectively, (1) frequency and degree of esophageal acidification during NAB, and (2) frequency and severity of NAB while on ilaprazole versus omeprazole. METHODS: Fifty-eight consecutive patients with GERD on once daily ilaprazole, 10 mg (n = 28) or omeprazole, 20 mg (n = 30) for > one month underwent 24-hour impedance-pH monitoring prospectively. NAB was defined as intra-gastric pH one hour during night, and esophageal acidification as pH < 4 for any duration. Nocturnal symptoms (heartburn, regurgitation, and chest pain) were also recorded. RESULTS: Of the 58 patients (age 35.5 [inter-quartile range 26.5–46.0] years, 38 [65.5%], 42 (72.4%) had NAB. Though patients with NAB had lower nocturnal intra-gastric pH than without (2.8 [1.9–4.1] vs 5.7 [4.6–6.8], P < 0.001), frequency and duration of nocturnal esophageal acidification (17/42 vs 4/16, P = 0.360 and 0.0 [0.0–1.0] vs 0.0 [0.0–0.3] minutes, P = 0.260, respectively) and symptoms were comparable (13/42 vs 6/16, P = 0.750). Though ilaprazole was associated with less NABs (1 [range 1–2, n = 19] vs 1 [range 1–3, n = 23], P = 0.010) than omeprazole, the frequency, duration, and mean intra-gastric pH during NAB were comparable (19/28 vs 23/30, P = 0.560; 117 [0–315] vs 159 [69–287] minutes, P = 0.500; 1.02 [0.7–1.4] vs 1.04 [0.44–1.3], P = 0.620, respectively). CONCLUSIONS: Though NAB was common while patients were on a proton pump inhibitor, esophageal acidification was uncommon. Frequency and severity of NAB were comparable among patients on ilaprazole and omeprazole, except for the lesser number of NABs with ilaprazole.

Mapping of Brain Activations to Rectal Balloon Distension Stimuli in Male Patients with Irritable Bowel Syndrome Using Functional Magnetic Resonance Imaging

BACKGROUND/AIMS: Irritable bowel syndrome (IBS) is associated with exaggerated cerebral response including emotional processing following visceral stimulation; though data on this issue is available in female IBS patients, it is scanty among males. Hence, we aimed to study brain response of male IBS patients following rectal balloon distension as compared to healthy controls using functional magnetic resonance imaging (fMRI). Data between diarrhea and constipation predominant IBS (IBS-D and IBS-C) were also compared. METHODS: Rectal balloon distension threshold was assessed in 20 male IBS patients (10 IBS-C and 10 IBS-D) and 10 age-matched male healthy controls. Subsequently, fMRI on all the participants was performed at their respective rectal pain threshold. The fMRI data were analysed using the Statistical Parametric Mapping software. RESULTS: IBS patients showed greater cerebral activations in insula, middle temporal gyrus, and cerebellum in the left hemisphere compared to healthy controls. Neural activation was found in bilateral precuneus/superior parietal lobules in controls but not in patients with IBS. The brain activation differed among IBS-C and IBS-D patients; while the right mid-cingulate cortex was activated in IBS-C, the left inferior orbito-frontal cortex, left calcarine, and bilateral fusiform gyri were activated among patients with IBS-D following rectal balloon distension. CONCLUSIONS: Brain response to rectal balloon distension differed among male patients with IBS and controls and among patients with IBS-C and IBS-D. Differential activation among patients with IBS-C and IBS-D was seen in the brain regions controlling affective motivation, homeostatic emotions, and autonomic responses to pain.