Functional dyspepsia: bye-bye to PPIs

Clinical effects of STW 5 (Iberogast) are not based on acceleration of gastric emptying in patients with functional dyspepsia and gastroparesis

STW 5, a herbal extract, is effective for the treatment of symptoms in patients with functional dyspepsia (FD). However, its mode of action is still unclear and a modulation of gastric motility is hypothesized. This multicentre, placebo-controlled double-blind study addressed the question of whether STW 5 accelerates gastric emptying in patients with FD and gastroparesis. One-hundred and three patients diagnosed with FD were randomly assigned to a treatment with either STW 5 or a liquid placebo for 28 days. The primary end point of the study was a change of a validated gastrointestinal symptom (GIS) score under treatment. Additionally, patients underwent a (13)C octanoic acid breath test for the assessment of the gastric half-emptying time (t(1/2)). Patients with prolonged t(1/2) were diagnosed with gastroparesis and requested to repeat the test at the end of treatment. A change of t(1/2) was defined a secondary study end point. t(1/2) was prolonged in 48.6% of patients in the STW 5 group and in 43.8% of the placebo group. During treatment, t(1/2) increased non-significantly in patients treated with STW 5 (+23 +/- 109 min; P = 0.51) and slightly accelerated among patients in the placebo arm (-26 +/- 51 min; P = 0.77) (P = 0.49). The improvement of the GIS (P = 0.08) and the proportion of patients with a treatment response (P = 0.03) were more pronounced in the STW 5 group. Our findings suggest that the clinical effects of STW 5 in patients with FD and gastroparesis are not directly mediated by an acceleration of gastric emptying. A clear-cut correlation with symptom improvement is still lacking.

Efficacy and safety of pantoprazole 20 mg once daily treatment in patients with ulcer-like functional dyspepsia

OBJECTIVE

To investigate the efficacy of pantoprazole 20 mg once daily (o.d.) in relieving epigastric pain associated with ulcer-like functional dyspepsia.

RESEARCH DESIGN AND METHODS

In this double-blind, placebo-controlled, multicentre study, patients experiencing ulcer-like functional dyspepsia, with epigastric pain as the predominant symptom, were randomised to receive pantoprazole 20 mg or placebo o.d. for 28 days. Primary endpoint was the complete relief (i.e. absence) from epigastric pain after 28 days' treatment. The odds ratio (OR) for pantoprazole/placebo and its 95% confidence intervals (CIs) were determined. Significant superiority of pantoprazole was concluded if the value 1.0 was above this interval.

RESULTS

Of 419 patients (intention-to-treat [ITT]) randomised to treatment, 207 received pantoprazole and 212 received placebo. Epigastric pain relief was achieved after 28 days' treatment in 55% of pantoprazole recipients and 45% of placebo recipients (per-protocol [PP]: 58% and 47%, respectively). Pantoprazole demonstrated statistically significant superiority compared with placebo in the ITT (OR: 0.68; 95% CI: 0.46-0.99) and PP populations (OR: 0.64; 95% CI: 0.42-0.98). Pantoprazole was more efficacious than placebo in relieving heartburn and acid regurgitation after 7, 14 and 28 days of treatment. The sum score of gastrointestinal symptoms after 28 days was statistically significantly lower in the pantoprazole than placebo group. Fewer patients receiving concomitant psychotropic medication experienced relief from epigastric pain than those not receiving such medication. Adverse events did not significantly differ between pantoprazole and placebo.

CONCLUSIONS

Results of this study suggest that pantoprazole 20 mg is more efficacious than placebo, and is a well-tolerated treatment for relieving epigastric pain in patients with ulcer-like functional dyspepsia. Further research is needed to confirm these findings.

Esomeprazole 40 mg once a day in patients with functional dyspepsia: the randomized, placebo-controlled "ENTER" trial

OBJECTIVE

The etiologies of functional dyspepsia (FD) are unclear, but in some studies, treatment with a proton pump inhibitor has been beneficial. The objective of this study was to evaluate the efficacy of esomeprazole 40 mg once a day compared to placebo in achieving symptom relief in primary care patients with FD.

METHODS

This was a randomized, placebo-controlled trial in adult FD patients, who had at least moderate severity of symptoms, defined as a score of > or =4 on a 7-point Global Overall Symptom (GOS) scale. Patients were excluded if they had predominant symptoms of heartburn or regurgitation; after a normal baseline endoscopy, patients were randomized to esomeprazole 40 mg once daily or placebo for 8 wk. The primary outcome measure was symptom relief (GOS < or =2) at 8 wk.

RESULTS

Of the 502 enrolled patients, 224 were randomized. The main reasons for exclusion were abnormal endoscopic findings, especially esophagitis. A significantly greater proportion of patients in the esomeprazole group achieved symptom relief at 4 but not at 8 wk compared to placebo: 4 wk esomeprazole 50.5% versus placebo 32.2%, p= 0.009; 8 wk esomeprazole 55.1% versus placebo 46.1%, p= 0.16. A similar relationship at 4 and 8 wk was seen for symptom resolution (GOS = 1) and improvement (DeltaGOS > or =2).

CONCLUSION

For the primary outcome measure of symptom relief at 8 wk, there was no statistically significant difference between esomeprazole 40 mg once a day and placebo. However, at 4 wk, esomeprazole was significantly more effective than placebo for symptom relief. The difference in therapeutic gain between 4 and 8 wk was largely due to a higher placebo response rate at 8 wk.

The efficacy of proton pump inhibitors in nonulcer dyspepsia: a systematic review and economic analysis

BACKGROUND AND AIMS

The evidence that proton pump inhibitor (PPI) therapy affects symptoms of nonulcer dyspepsia is conflicting. We conducted a systematic review to evaluate whether PPI therapy had any effect in nonulcer dyspepsia and constructed a health economic model to assess the cost-effectiveness of this approach.

METHODS

Electronic searches were performed using the Cochrane Controlled Trials Register, MEDLINE, EMBASE, CINAHL, and SIGLE until September 2002. Dyspepsia outcomes were dichotomized into cured/improved versus same/worse. Results were incorporated into a Markov model comparing health service costs and benefits of PPI with antacid therapy over 1 year.

RESULTS

Eight trials were identified that compared PPI therapy with placebo in 3293 patients. The relative risk of remaining dyspeptic with PPI therapy versus placebo was .86 (95% confidence interval, .78-.95; P = .003, random-effects model) with a number needed to treat of 9 (95% confidence interval, 5-25). There was statistically significant heterogeneity between trials (heterogeneity chi(2) = 30.05; df = 7; P < .001). The PPI strategy would cost an extra US dollar 278/month free from dyspepsia if the drug cost US dollar 90/month. If a generic price of US dollar 19.99 is used, then a PPI strategy costs an extra US dollar 57/month free from dyspepsia. A third-party payer would be 95% certain that PPI therapy would be cost-effective, provided they were willing to pay US dollar 94/month free from dyspepsia.

CONCLUSIONS

PPI therapy may be a cost-effective therapy in nonulcer dyspepsia, provided generic prices are used.

New developments in the treatment of functional dyspepsia

Functional dyspepsia is a clinical syndrome defined by chronic or recurrent pain or discomfort in the upper abdomen of unknown origin. Although generally accepted, investigators differently interpret this definition and clinical trials are often biased by inhomogeneous inclusion criteria. The poorly defined multifactorial pathogenesis of dyspeptic symptoms has hampered efforts to develop effective treatments. A general agreement exists on the irrelevant role played by Helicobacter pylori in the pathophysiology of functional dyspepsia. Gastric acid secretion is within normal limits in patients with functional dyspepsia but acid related symptoms may arise in a subgroup of them. Proton pump inhibitors appear to be effective in this subset of patients with dyspepsia. Non-painful dyspeptic symptoms are suggestive of underlying gastrointestinal motor disorders and such abnormalities can be demonstrated in a substantial proportion of patients. Postprandial fullness and vomiting have been associated with delayed gastric emptying of solids, and early satiety and weight loss to postcibal impaired accommodation of the gastric fundus. Prokinetics have been shown to exert beneficial effects, at least in some patients with dyspepsia. In contrast, drugs enhancing gastric fundus relaxation have been reported to improve symptoms, although conflicting results have also been published. An overdistended antrum may also generate symptoms, but its potential pathogenetic role and the effects of drugs on this abnormality have never been investigated formally. Visceral hypersensitivity plays a role in some dyspeptic patients and this abnormality is also a potential target for treatment. Both chemo- and mechanoreceptors can trigger hyperalgesic responses. Psychosocial abnormalities have been consistently found in functional digestive syndromes, including dyspepsia. Although useful in patients with irritable bowel syndromes (IBS), antidepressants have been only marginally explored in functional dyspepsia. Among the new potentially useful agents for the treatment of functional dyspepsia, serotonin 5-HT(4) receptor agonists have been shown to exert a prokinetic effect. Unlike motilides, 5-HT(4) receptor agonists do not appear to increase the gastric fundus tone and this may contribute to improve symptoms. 5-HT(3) receptor antagonists have been investigated mainly in the IBS and the few studies performed in functional dyspepsia have provided conflicting results. Also, kappa-opioid receptor agonists might be useful for functional digestive syndromes because of their antinociceptive effects, but available results in functional dyspepsia are scanty and inconclusive. Other receptors that represent potential clinical targets for antagonists include purinoceptors (i. e., P2X2/3 receptors), NMDA receptors (NR2B subtype), protease-activated receptor-2, the vanilloid receptor-1, tachykinin receptors (NK(1)/NK(2)) and cholecystokinin (CCK)(1) receptors.