Does short-term treatment with proton pump inhibitors cause rebound aggravation of symptoms?

Rebound Acid Hypersecretion after Withdrawal of Long-Term Proton Pump Inhibitor (PPI) Treatment-Are PPIs Addictive?

Proton pump inhibitors (PPIs) are widely used in the long-term treatment of gastroesophageal reflux disease (GERD) and other upper gastrointestinal disorders, such as the healing of peptic ulcers and/or prophylactic treatment of peptic ulcers. PPIs are also widely used as symptomatic treatment in patients with functional dyspepsia. One of the adverse effects of the long-term use of PPI is rebound acid hypersecretion (RAHS), which can occur after the withdrawal of PPI therapy due to a compensatory increase in gastric acid production. Mechanisms of the RAHS have been well established. Studies have shown that pentagastrin-stimulated acid secretion after the discontinuation of PPIs increased significantly compared to that before treatment. In healthy volunteers treated with PPIs, the latter induced gastrointestinal symptoms in 40-50% of subjects after the discontinuation of PPI therapy but after stopping the placebo. It is important for practicing physicians to be aware and understand the underlying mechanisms and inform patients about potential RAHS before discontinuing PPIs in order to avoid continuing unnecessary PPI therapy. This is important because RAHS may lead patients to reuptake PPIs as symptoms are incorrectly thought to originate from the recurrence of underlying conditions, such as GERD. Mechanisms of RAHS have been well established; however, clinical implications and the risk factors for RAHS are not fully understood. Further research is needed to facilitate appropriate management of RAHS in the future.

Problems Associated with Deprescribing of Proton Pump Inhibitors

Proton pump inhibitors (PPIs) are recommended as a first-line treatment for gastroesophageal reflux disease (GERD) and other acid related disorders. In recent years, concerns have been raised about the increasing prevalence of patients on long-term PPI therapy and inappropriate PPI use. It is well known that short-term PPI therapy is generally well tolerated and safe; however, their extensive long-term use is a major global issue. One of these long-standing concerns is PPI-induced gastrin elevation secondary to hypoacidity. Hypergastrinemia is believed to play a role in rebound hyperacidity when PPIs are discontinued resulting in induced dyspeptic symptoms that might result in the reinstitution of therapy. Gastrin exerts tropic effects in the stomach, especially on enterochromaffin-like (ECL) cells, and concerns have also been raised regarding the potential progression to dysplasia or tumor formation following long-term therapy. It is well known that a substantial number of patients on long-term PPI therapy can discontinue PPIs without recurrence of symptoms in deprescribing trials. What is unknown is how sustainable deprescribing should be undertaken in practice and how effective it is in terms of reducing long-term outcomes like adverse drug events, morbidity and mortality. Moreover, there is no clear consensus on when and how deprescribing strategies should be attempted in practice. This review sought to summarize the harms and benefits of long-term PPI therapy with special focus on gastrin elevation and its relation to deprescribing studies and future interventions that may improve PPI use.

The effects of long-term therapy with proton pump inhibitors on meal stimulated gastrin

BACKGROUND

Dyspepsia develops in healthy volunteers after withdrawal of proton-pump inhibitors. This phenomenon, attributed to rebound acid hypersecretion, is thought to be mediated by reflex hypergastrinemia.

AIMS

To measure fasting and postprandial gastrin in patients on long-term proton-pump inhibitor treatment and correlate gastrin levels with the duration of treatment and other potential predictors.

METHODS

In this cross sectional study patients, with erosive esophagitis, on long-term proton-pump inhibitor treatment and healthy controls underwent gastrin measurements at baseline and four times following a meal and Helicobacter pylori status was determined.

RESULTS

A total of 100 patients and 50 controls were studied. Pre- and postprandial gastrin levels were higher in patients (p<0.001). No significant correlation was found between the area under the gastrin-curve and the treatment duration. Female patients had significantly higher gastrin levels than males pre- and postprandial, whereas such differences was not found in the control group. Female gender was the only independent predictor of s-gastrin levels (OR 2.50 compared to males, 95% CI: 1.08-5.76, p=0.032) in the patient group.

CONCLUSION

Gastrin values were higher in patients compared to controls. There was no correlation between gastrin levels and treatment duration. Female patients had significantly higher gastrin values than males.

Safety of long-term PPI therapy

Proton pump inhibitors have become the mainstay of medical treatment of acid-related disorders. Long-term use is becoming increasingly common, in some cases without a proper indication. A large number of mainly observational studies on a very wide range of possible associations have been published in the past decade and are critically reviewed in this article and the existing evidence is evaluated and translated into possible clinical consequences. Based on the existing evidence the benefits of PPI treatment seem to outweigh potential risks in the large majority of patients especially if PPI use is based on a relevant indication. The concern for complications should primarily be directed at elderly, malnourished with significant co-morbidity. In this population an increased risk for enteric infections, fractures and nutritional deficiencies might have clinical consequences and should lead to a careful evaluation of the indication for PPI treatment.

Systematic review: symptoms of rebound acid hypersecretion following proton pump inhibitor treatment

INTRODUCTION

While the physiological existence of rebound acid hypersecretion (RAHS) after withdrawal of proton pump inhibitors (PPI) therapy is established, the clinical implications are less certain. It has been speculated that a clinical relevant rebound phenomenon may be responsible for difficulties in getting off acid-suppressive medication and partly explain the increase in long-term use of PPI. A number of studies addressing this issue have been published recently. The authors aimed to systematically review the existing evidence of clinically relevant symptoms caused by acid rebound following PPI treatment.

MATERIAL AND METHODS

PubMed was searched using the terms "rebound acid hypersecretion" and generic names of PPIs.

RESULTS

Five studies were included. Two studies on asymptomatic volunteers found that 44% experienced acid-related symptoms up to 4 weeks after treatment was withdrawn. Symptoms were generally mild to moderate and mainly heartburn and regurgitation. Three studies, using patients with reflux disease, found no signs of symptoms caused by acid rebound.

CONCLUSION

Gastric acid rebound hypersecretion following PPI therapy induces reflux-like symptoms post-treatment in asymptomatic volunteers, but the significance of this in patient populations is not clear. The studies in patients with reflux disease found no evidence of symptomatic RAHS, but these studies were hampered by severe methodological weaknesses.

Inappropriate prescribing of proton pump inhibitors in older patients: effects of an educational strategy

BACKGROUND

An increasing number of older patients are prescribed proton pump inhibitors (PPIs). However, the extent of inappropriate PPI prescribing in this group is largely unknown.

OBJECTIVE

We sought to identify clinical and demographic factors associated with inappropriate PPI prescribing in older patients and to assess the effects of a targeted educational strategy in a controlled hospital environment.

METHODS

Clinical and demographic characteristics and full medication exposure on admission were recorded in 440 consecutive older patients (mean ± SD age 84 ± 7 years) admitted to a teaching hospital between 1 February 2011 and 30 June 2011. A 4-week educational strategy to reduce inappropriate PPI prescribing during hospital stay, either by stopping or reducing PPI doses, was conducted within the study period. The main outcome measures of the study were the incidence of inappropriate PPI prescribing and the effects of interventions to reduce it.

RESULTS

On admission, PPIs were established therapy in 164 patients (37%). This was considered inappropriate in 100 patients (61%). Lower Charlson Comorbidity Index score (odds ratio [OR] 0.76; 95% CI 0.57, 0.94; p = 0.006) and history of dementia (OR 1.65; 95% CI 1.28, 1.83; p = 0.005) were independently associated with inappropriate PPI prescribing. Interventions to reduce inappropriate PPI prescribing occurred more frequently during and after the education phase (frequency of interventions in patients with inappropriate PPI prescribing: pre-education phase 9%, during education phase 43%, and post-education phase 46%, p = 0.006). Prescribing interventions were not associated with acid rebound symptoms.

CONCLUSIONS

Inappropriate PPI prescribing in older patients is frequent and independently associated with co-morbidities and dementia. A targeted in-hospital educational strategy can significantly and safely reduce inappropriate PPI prescribing in the short term.

Withdrawing PPI therapy after healing esophagitis does not worsen symptoms or cause persistent hypergastrinemia: analysis of dexlansoprazole MR clinical trial data

OBJECTIVES

Withdrawal of proton pump inhibitors (PPIs) may induce symptoms in healthy volunteers, suggesting that discontinuing PPI therapy induces acid-peptic disease. Similar assessments in patients with documented acid-related disorders are lacking.

METHODS

We performed a retrospective analysis of data from 287 Helicobacter pylori-negative erosive esophagitis (EE) patients healed after 4 or 8 weeks of therapy with dexlansoprazole modified release (MR) or lansoprazole, and then randomized to placebo in 6-month maintenance trials. We compared serum gastrin levels and 24-h heartburn severity before enrollment in the healing trials (baseline) and after receiving placebo in the 6-month maintenance trials.

RESULTS

Mean gastrin values at maintenance months 1 and 3 were essentially unchanged (median changes, 1.0 and -1.0 pg/ml), showing that gastrin normalized within 1 month of discontinuing PPIs and remained flat. Mean heartburn severity at maintenance month 1 was <1 on a 5-point scale (1=mild) and significantly lower than at baseline (median decrease, 0.41 points; P≤0.001). Heartburn severity in patients healed at week 4 or 8 with either PPI was generally similar, suggesting that neither longer exposure nor more potent therapy was associated with rebound. In those with month 2 data, mean heartburn severity at months 1 and 2 was significantly lower than baseline (median decrease, 0.54 and 0.58 points; both P<0.001), indicating an ongoing symptom response for 2 months after PPI withdrawal.

CONCLUSIONS

In H. pylori-negative EE patients, there was no indication of recurring heartburn symptom worsening beyond baseline levels within 2 months of discontinuing 4-8 weeks of PPI therapy.

Pharmacokinetic drug interaction profiles of proton pump inhibitors

Proton pump inhibitors are used extensively for the treatment of gastric acid-related disorders because they produce a greater degree and longer duration of gastric acid suppression and, thus, better healing rates, than histamine H(2) receptor antagonists. The need for long-term treatment of these disorders raises the potential for clinically significant drug interactions in patients receiving proton pump inhibitors and other medications. Therefore, it is important to understand the mechanisms for drug interactions in this setting. Proton pump inhibitors can modify the intragastric release of other drugs from their dosage forms by elevating pH (e.g. reducing the antifungal activity of ketoconazole). Proton pump inhibitors also influence drug absorption and metabolism by interacting with adenosine triphosphate-dependent P-glycoprotein (e.g. inhibiting digoxin efflux) or with the cytochrome P450 (CYP) enzyme system (e.g. decreasing simvastatin metabolism), thereby affecting both intestinal first-pass metabolism and hepatic clearance. Although interactions based on the change of gastric pH are a group-specific effect and thus may occur with all proton pump inhibitors, individual proton pump inhibitors differ in their propensities to interact with other drugs and the extent to which their interaction profiles have been defined. The interaction profiles of omeprazole and pantoprazole have been studied most extensively. A number of studies have shown that omeprazole carries a considerable potential for drug interactions, since it has a high affinity for CYP2C19 and a somewhat lower affinity for CYP3A4. In contrast, pantoprazole appears to have lower potential for interactions with other medications. Although the interaction profiles of esomeprazole, lansoprazole and rabeprazole have been less extensively investigated, evidence suggests that lansoprazole and rabeprazole seem to have a weaker potential for interactions than omeprazole. Although only a few drug interactions involving proton pump inhibitors have been shown to be of clinical significance, the potential for drug interactions should be taken into account when choosing a therapy for gastric acid-related disorders, especially for elderly patients in whom polypharmacy is common, or in those receiving a concomitant medication with a narrow therapeutic index.

On-demand PPI requirements in patients with endoscopy-negative GERD

GOALS

To evaluate the need for on-demand treatment with proton pump inhibitor in patients with endoscopy-negative GERD.

BACKGROUND

Studies indicate that on-demand therapy is suitable for patients without mucosal disease, but the need for PPI in a monotherapy situation is not known.

STUDY

Forty-one patients with heartburn and/or acid reflux of more than 3 months duration participated in the study. All were endoscopy-negative and had responded positive to a test with lansoprazole 60 mg x 1 for 7 days. Twenty-four hour pH monitoring was attempted in all, but failed in 4. Twenty-eight had pH <4 more than 4% of the time, 9 had less. During a 3-month period, the patients were allowed to take 1 capsule 30 mg lansoprazole on-demand, maximum 2 capsules a day. The remaining capsules were counted monthly.

RESULTS

In the 3-month period, the median mean daily consumption was 1.06 capsule (95% CI: 0072-1.09). No significant difference was found between those with normal or abnormal 24-hour pH-metry. Sixty-three percent used 6 or more capsules a week.

CONCLUSION

Patients with longstanding negative-endoscopy reflux disease, whether abnormal or normal 24-hour pH-metry, have symptoms that demand effective therapy. Using PPI on-demand as monotherapy, most patients will need 1 capsule per day.

Rebound hypersecretion after inhibition of gastric acid secretion

Drugs inhibiting gastric acid secretion are widely used because of the high prevalence of acid-related disorders. However, from clinical experience it seems that symptom relapse is common after withdrawal of these drugs. Experimental as well as clinical studies have demonstrated an increased acid secretion after a period of treatment with either histamine 2 receptor antagonists or proton pump inhibitors. Rebound hypersecretion is likely to reflect the following sequence of events: Long-term inhibition of acid output is accompanied by elevated serum gastrin levels, leading to enterochromaffin-like cell activation and proliferation, resulting in increased amounts of histamine being mobilized from these cells to stimulate the parietal cells. The clinical consequences of rebound hypersecretion have not been settled.

Personal view: rationale and proposed algorithms for symptom-based proton pump inhibitor therapy for gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease and non-erosive reflux disease are chronic, highly prevalent conditions requiring long-term treatment that is both effective and practical. On-demand therapy with a proton pump inhibitor may meet that need. It is becoming a mainstay of long-term treatment because it reduces the risk of over- and under-treatment, is cost-effective and user friendly. Epidemiological and clinical observations speak also in its favour. However, for the anticipated benefits of on-demand therapy to accrue in clinical practice, on-demand treatment algorithms are required. These algorithms must specify the initial evaluation and treatment of candidates, and follow-up protocols for an on-demand strategy. Our group has developed such algorithms, which are presented here.