Split-dose preparation for colonoscopy increases adenoma detection rate: a randomised controlled trial in an organised screening programme

OBJECTIVE

Although a split regimen of bowel preparation has been associated with higher levels of bowel cleansing, it is still uncertain whether it has a favourable effect on the adenoma detection rate (ADR). The present study was aimed at evaluating whether a split regimen was superior to the traditional 'full-dose, day-before' regimen in terms of ADR.

DESIGN

In a multicentre, randomised, endoscopist-blinded study, 50-69-year-old subjects undergoing first colonoscopy after positive-faecal immunochemical test within an organised colorectal cancer organised screening programmes were 1:1 randomised to receive low-volume 2-L polyethylene glycol (PEG)-ascorbate solution in a 'split-dose' (Split-Dose Group, SDG) or 'day-before' regimen (Day-Before Group, DBG). The primary endpoint was the proportion of subjects with at least one adenoma. Secondary endpoints were the detection rates of advanced adenomas and serrated lesions at per-patient analysis and the total number of lesions.

RESULTS

690 subjects were included in the study. At per-patient analysis, the proportion of subjects with at least one adenoma was significantly higher in the SDG than in the DBG (183/345, 53.0% vs 141/345, 40.9%, relative risk (RR) 1.22, 95% CI 1.03 to 1.46); corresponding figures for advanced adenomas were 26.4% (91/345) versus 20.0% (69/345, RR 1.35, 95% CI 1.06 to 1.73). At per-polyp analysis, the total numbers of both adenomas and advanced adenomas per subject were significantly higher in the SDG (1.15 vs 0.8, p <0.001; 0.36 vs 0.22, p<0.001).

CONCLUSIONS

In an organised screening setting, the adoption of a split regimen resulted into a higher detection rate of clinically relevant neoplastic lesions, thus improving the effectiveness of colonoscopy. Based on such evidence, the adoption of a split regimen for colonoscopy should be strongly recommended.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02178033.

Carbonated beverages and gastrointestinal system: between myth and reality

A wealth of information has appeared on non-scientific publications, some suggesting a positive effect of carbonated beverages on gastrointestinal diseases or health, and others a negative one. The evaluation of the properties of carbonated beverages mainly involves the carbon dioxide with which they are charged. Scientific evidence suggests that the main interactions between carbon dioxide and the gastrointestinal system occur in the oral cavity, the esophagus and the stomach. The impact of carbonation determines modification in terms of the mouthfeel of beverages and has a minor role in tooth erosion. Some surveys showed a weak association between carbonated beverages and gastroesophageal reflux disease; however, the methodology employed was often inadequate and, on the overall, the evidence available on this topic is contradictory. Influence on stomach function appears related to both mechanical and chemical effects. Symptoms related to a gastric mechanical distress appear only when drinking more than 300 ml of a carbonated fluid. In conclusion there is now sufficient scientific evidence to understand the physiological impact of carbonated beverages on the gastrointestinal system, while providing a basis for further investigation on the related pathophysiological aspects. However, more studies are needed, particularly intervention trials, to support any claim on the possible beneficial effects of carbonated beverages on the gastrointestinal system, and clarify how they affect digestion. More epidemiological and mechanistic studies are also needed to evaluate the possible drawbacks of their consumption in terms of risk of tooth erosion and gastric distress.

Sweetened carbonated drinks do not alter upper digestive tract physiology in healthy subjects

Sweetened carbonated beverages are widely consumed, which has fuelled several conflicting opinions about their effects on upper digestive tract functions. We aimed to evaluate the effect of sweetened carbonated drinks, consumed with a standard meal, on gastro-oesophageal reflux, gastric emptying and gallbladder contraction and postmeal sensations in healthy subjects. Thirteen healthy volunteers (seven women, six males; median age 22 years) were tested following the intake of 300 mL sweetened water containing increasing concentrations of carbon dioxide (seven subjects), and of 300 mL sweetened commercial flavoured drink with and without carbon dioxide (six subjects). Gastro-oesophageal reflux, gastric emptying and gallbladder contraction were studied by pH-impedance, octanoic acid breath test and ultrasound respectively. Gastro-oesophageal refluxes were significantly increased 1 h after meal with both water and commercial beverages; only sweetened water without carbon dioxide determined a persistently increasing number of refluxes 2 h postmeal. No differences were found for gastric emptying, gallbladder contraction or postmeal symptoms with any of the beverages tested. This study shows that 300 mL of sweetened carbonated beverage with different levels of carbonation or a commercial soft drink do not modify the physiology of the upper digestive tract.

Medical treatment of gastro-oesophageal reflux disease

The introduction, in the last two decades, of strongly effective acid suppressant drugs, such as proton pump inhibitors has radically modified the way of treating gastro-oesophageal reflux disease. In clinical trials, these agents have constantly been demonostrated to be more effective than other acid-suppressant agents such as H2-receptor antagonists in relief of symptoms and healing of oesophagitis, the two main goals of gastro-oesophageal reflux disease treatment. They provide a prompt clinical benefit to most patients and can be safely used in long-term gastro-oesophageal reflux disease management for maintenance of clinical and endoscopic remission, because of their negligible adverse-events profile. Therapeutic protocols vary depending on the severity of symptoms and the degree of oesophageal injury. In patients with mild symptoms and with minimal lesions at endoscopy, a "step-down" therapy, in the short-term, is considered the best medical strategy, while in the long-term the therapy "on-demand" appears to be a reasonable approach. Patients with non-erosive disease seem to have a lower response rate to proton pump inhibitor treatment. More severe grades of oesophagitis must be treated with full-dose proton pump inhibitors without withdrawal. Data on the treatment of extra-oesophageal manifestations of gastro-oesophageal reflux disease are few and controversial. Overall, it appears that patients with extra-oesophageal symptoms of gastro-oesophageal reflux disease must be treated with higher doses of pharmacological treatment, principally with proton pump inhibitors, and with longer periods of treatment to achieve complete relief of symptoms, as compared with patients with typical symptoms of gastro-oesophageal reflux disease and erosive oesophagitis.

Oesophageal acid exposure and altered neurocardiac function in patients with GERD and idiopathic cardiac dysrhythmias

BACKGROUND

Oesophageal sensory stimuli alter neurocardiac function through autonomic reflexes.

AIM

To evaluate in patients with idiopathic supraventricular cardiac dysrhythmias and gastro-oesophageal reflux disease (GERD) whether GE reflux alters neurocardiac function and the effect of acid suppression on cardiac symptoms.

METHODS

Thirty-two patients (13 females and 19 males; age: 20-69 years) with dysrhythmias plus GERD, and nine patients (five females and four males; age: 43-58 years) with GERD only, underwent simultaneous 24-h pH-metry and ECG monitoring. Power spectrum analysis of heart rate variability (PSHRV) was obtained with both its low frequency (LF, sympathetic modulation) and high frequency (HF, vagal modulation) components. Hourly mean oesophageal pH and LF/HF ratio were correlated. A 3 months full-dosage PPI therapy (esomeprazole 40 mg/day) was prescribed.

RESULTS

In 18 (56%) of the 32 patients with dysrhythmia and in none with GERD only, a significant (P < 0.05) correlation between oesophageal pH and LF/HF ratio (oesophagus-heart correlation) was observed. A significant reduction of cardiac symptoms after PPI therapy was observed only in these patients (13/16 vs. 4/11, P < 0.01).

CONCLUSIONS

This study has identified a subgroup of dysrhythmic patients in whom the oesophageal acid stimulus elicited cardiac autonomic reflexes. In these patients acid suppression seems to improve GERD and cardiac symptoms.