Hypochlorhydria from short-term omeprazole treatment does not inhibit intestinal absorption of calcium, phosphorus, magnesium or zinc from food in humans

Guidelines on optimizing the use of proton pump inhibitors: PPI stewardship

Proton pump inhibitors (PPIs) have been available for over three decades and are among the most commonly prescribed medications. They are effective in treating a variety of gastric acid-related disorders. They are freely available and based on current evidence, use of PPIs for inappropriate indications and duration appears to be common. Over the years, concerns have been raised on the safety of PPIs as they have been associated with several adverse effects. Hence, there is a need for PPI stewardship to promote the use of PPIs for appropriate indication and duration. With this objective, the Indian Society of Gastroenterology has formulated guidelines on the rational use of PPIs. The guidelines were developed using a modified Delphi process. This paper presents these guidelines in detail, including the statements, review of literature, level of evidence and recommendations. This would help the clinicians in optimizing the use of PPIs in their practice and promote PPI stewardship.

Proton Pump Inhibitors, Kidney Damage, and Mortality: An Updated Narrative Review

Since their approval by the Food and Drug Administration (FDA) in 1989, proton pump inhibitors (PPIs) have become one of the most highly utilized drugs in the United States, assuming a position as one of the top 10 most prescribed medications in the country. The purpose of PPIs is to limit the amount of gastric acid secreted by the parietal cells via irreversible inhibition of the H+/K+-ATPase pump, therefore maintaining an elevated gastric acid pH of greater than 4 for 15-21 h. Even though PPIs have many clinical uses, they are not without their adverse effects, mimicking achlorhydria. Besides electrolyte abnormalities and vitamin deficiencies, long-term use of PPIs has been linked to acute interstitial nephritis, bone fractures, poor COVID-19 infection outcomes, pneumonia, and possibly an increase in all-cause mortality. The causality between PPI use and increased mortality and disease risk can be questioned since most studies are observational. Confounding variables can greatly affect an observational study and explain the wide-ranging associations with the use of PPIs. Patients on PPIs are generally older, obese, sicker with a higher number of baseline morbidities, and on more medications than the compared PPI non-users. These findings suggest that PPI users are at a higher risk of mortality and complications based on pre-existing conditions. This narrative review aims to update readers on the concerning effects that proton pump inhibitor use can have on patients and give providers a resource to create informed decisions on appropriate PPI use.

Bone microstructure in proton pump inhibitor users

OBJECTIVES

We assessed skeletal microstructure and stiffness in proton pump inhibitor (PPI) users compared to non-users with high resolution peripheral quantitative computed tomography (HRpQCT) and microfinite element analysis (μFEA) and other modalities. Relationships between PPI dose/frequency and bone parameters were evaluated.

METHODS

We cross-sectionally assessed skeletal health in 601 older (≥age 65 years) adults (130 PPI users and 471 non-users) participating in a multi-ethnic population-based study of aging.

RESULTS

PPI users tended to have more comorbidities and take more medications than non-users. Female PPI users (n = 100) were more likely to be non-Caucasian, shorter with higher BMI, and more likely to have diabetes, lower physical activity and be using anti-depressants and thiazide diuretics compared to non-users (n = 302). Male PPI users (n = 30) were more likely to have liver disease than non-users (n = 169). In women, historical fractures (53.0 % vs. 43.4 %, p = 0.05) and falls (38 % vs. 26.8 %, p = 0.04) tended to be more frequent in PPI users compared to non-users. Number of falls was higher in women reporting daily rather than intermittent PPI use (1.8/year vs. 1.0/year, p < 0.001). In women, there were no differences in any HRpQCT or μFEA parameter. By HRpQCT, covariate-adjusted cortical volumetric bone density (Ct.vBMD) was 4.2 % lower in male PPI users vs. non-users at the tibia (p = 0.04), but this did not result in reduced stiffness. There were no other differences by HRpQCT at the tibia or radius.

CONCLUSIONS

PPI use was not associated with altered skeletal microstructure or stiffness in elderly men and women. The results do not support a relationship between PPI use and microstructure.

Proton Pump Inhibitors and Bone Health: An Update Narrative Review

Proton pump inhibitors (PPIs) are an antacid drug often used in acid-related disorders. They decrease acid secretion in the stomach by blocking an enzyme called H+/K+ ATPase which controls acid production. Introduced to the market in 1989, their use has increased rapidly worldwide and they are now among the top 10 most prescribed drugs in the United States. As of 2015, the FDA has already approved six drugs of this class (omeprazole, esomeprazole, lansoprazole, dexlansoprazole, pantoprazole and rabeprazole). Recently, the risks and benefits of long-term PPI use were questioned and many studies indicated that their use should be carefully considered, especially in young patients, whose treatment with these drugs could last many years. Even greater concerns have been raised about a potential positive association between PPIs and osteoporotic fracture risk including the hip, spine and wrist. Although based on observational studies, there is substantial evidence associating the long-term use of PPIs and fracture. This relationship is only partially admitted due to the lack of consistent effects of PPIs on bone mineral density loss. Therefore, this narrative review aimed to discuss the recent findings pertaining to the risk of osteoporotic fracture associated with PPIs, in particular prolonged use, and to call for further research to elucidate the mechanisms associated with this bone fragility.

Micronutrient Improvement of Epithelial Barrier Function in Various Disease States: A Case for Adjuvant Therapy

The published literature makes a very strong case that a wide range of disease morbidity associates with and may in part be due to epithelial barrier leak. An equally large body of published literature substantiates that a diverse group of micronutrients can reduce barrier leak across a wide array of epithelial tissue types, stemming from both cell culture as well as animal and human tissue models. Conversely, micronutrient deficiencies can exacerbate both barrier leak and morbidity. Focusing on zinc, Vitamin A and Vitamin D, this review shows that at concentrations above RDA levels but well below toxicity limits, these micronutrients can induce cell- and tissue-specific molecular-level changes in tight junctional complexes (and by other mechanisms) that reduce barrier leak. An opportunity now exists in critical care—but also medical prophylactic and therapeutic care in general—to consider implementation of select micronutrients at elevated dosages as adjuvant therapeutics in a variety of disease management. This consideration is particularly pointed amidst the COVID-19 pandemic.

Proton Pump Inhibitors Inhibit PHOSPHO1 Activity and Matrix Mineralisation In Vitro

Proton pump inhibitors (PPIs) have been associated with an increased risk of fragility fractures in pharmaco-epidemiological studies. The mechanism is unclear, but it has been speculated that by neutralising gastric acid, they may reduce intestinal calcium absorption, causing secondary hyperparathyroidism and bone loss. Here we investigated that hypothesis that the skeletal effects of PPI might be mediated by inhibitory effects on the bone-specific phosphatase PHOSPHO1. We found that the all PPIs tested inhibited the activity of PHOSPHO1 with IC50 ranging between 0.73 µM for esomeprazole to 19.27 µM for pantoprazole. In contrast, these PPIs did not inhibit TNAP activity. We also found that mineralisation of bone matrix in primary osteoblast cultures was inhibited by several PPIs in a concentration dependent manner. In contrast, the histamine-2 receptor antagonists (H2RA) nizatidine, famotidine, cimetidine and ranitidine had no inhibitory effects on PHOSPHO1 activity. Our experiments show for the first time that PPIs inhibit PHOSPHO1 activity and matrix mineralisation in vitro revealing a potential mechanism by which these widely used drugs are associated with the risk of fractures.

Polypharmacy and Malnutrition Management of Elderly Perioperative Patients with Cancer: A Systematic Review

Malnutrition, which commonly occurs in perioperative patients with cancer, leads to decreased muscle mass, hypoalbuminemia, and edema, thereby increasing the patient's risk of various complications. Thus, the nutritional management of perioperative patients with cancer should be focused on to ensure that surgical treatment is safe and effective, postoperative complications are prevented, and mortality is reduced. Pathophysiological and drug-induced factors in elderly patients with cancer are associated with the risk of developing malnutrition. Pathophysiological factors include the effects of tumors, cachexia, and anorexia of aging. Metabolic changes, such as inflammation, excess catabolism, and anabolic resistance in patients with tumor-induced cancer alter the body's ability to use essential nutrients. Drug-induced factors include the side effects of anticancer drugs and polypharmacy. Drug-drug, drug-disease, drug-nutrient, and drug-food interactions can significantly affect the patient's nutritional status. Furthermore, malnutrition may affect pharmacokinetics and pharmacodynamics, potentiate drug effects, and cause side effects. This review outlines polypharmacy and malnutrition, the impact of malnutrition on drug efficacy, drug-nutrient and drug-food interactions, and intervention effects on polypharmacy or cancer cachexia in elderly perioperative patients with cancer.

Biomechanical and biochemical evaluation of the effect of systemic application of omeprazole on the osseointegration of titanium implants

BACKGROUND

This study aimed to investigate the effects of systemic omeprazole treatment on the osseointegration of titanium implants.

MATERIAL AND METHODS

After surgical insertion of titanium implants into the metaphyseal part of rats' both right and left tibial bones, the animals were randomly divided into three equal groups: control (n = 8), omeprazole dosage-1 (n = 8) (OME-1), and omeprazole dosage-2 (n = 8) (OME-2) and totally 48 implants were surgically integrated. The rats in the control group received no treatment during the four-week postoperative experimental period. In the OME-1 and OME-2 groups, the rats received omeprazole in doses of 5 and 10 mg/kg, respectively, every 3 days for 4 weeks. After the experimental period, the rats were euthanized. One rat died in each group and the study was completed with seven rats in each group. Blood serum was collected for biochemical analysis, and the implants and surrounding bone tissue were used for biomechanical reverse-torque analysis. In the biomechanical analysis, implants that were not properly placed and were not osseointegrated were excluded from the evaluation.

RESULTS

One-way analysis of variance and Tukey's honestly significant difference test and Student's t test were used for statistical analysis. The reverse-torque test (control (n = 9), OME-1 (N = 7), and OME-2 (n = 7)) analysis of biochemical parameters (alkaline phosphatase, calcium, phosphorus, aspartate aminotransferase, alanine amino transferase, urea, and creatinine) revealed no significant differences between the groups (control (n = 7), OME-1 (N = 7), and OME-2 (n = 7)) (P > 0.05).

CONCLUSIONS

Omeprazole had no biomechanical or biochemical effects on the osseointegration process of titanium implants.

Proton Pump Inhibitors and Fractures in Adults: A Critical Appraisal and Review of the Literature

Despite the large number of patients worldwide being on proton pump inhibitors (PPIs) for acid-related gastrointestinal disorders, uncertainty remains over their long-term safety. Particularly, the potential side effects of these drugs on bone health have been evaluated in the last years. The purpose of our narrative review is to gather and discuss results of clinical studies focusing on the interactions between PPIs and fracture risk. Data generated mainly from nested case-control studies and meta-analysis suggest that long-term/high-dose PPIs users are characterized by an increased risk of fragility fractures, mainly hip fractures. However, in these studies, the PPIs-induced bone impairment is often not adjusted for different confounding variables that could potentially affect bone health, and exposure to PPIs was reported using medical prescriptions without adherence evaluation. The mechanisms of the PPI-related bone damage are still unclear, but impaired micronutrients absorption, hypergastrinemia, and increased secretion of histamine may play a role. Clinicians should pay attention when prescribing PPIs to subjects with a preexistent high risk of fractures and consider antiosteoporotic drugs to manage this additive effect on the bone. However, further studies are needed to clarify PPIs action on the bone.

Effect of proton pump inhibitors on dental implants: A systematic review and meta-analysis

Aim

The present systematic review aims to determine the evidence on the impact of proton pump inhibitors (PPIs) on dental implants.

Settings and Design

This secondary qualitative and quantitative research was done using a pre-specified question and inclusion criteria.

Materials and Methods

A systematic search was conducted in electronic databases such as PubMed, Ovid, and Cochrane. All the studies that assessed the effect of PPIs on dental implants were included, irrespective of the design. Literature review, letter to editors, short commentaries, and opinion articles were excluded.

Results and Statistical Analysis Used

A total of three publications fulfilled the inclusion criteria. All these included articles were retrospective cohort studies; the methodological quality was assessed using Newcastle-Ottawa scale. A total of 452 implants were placed in 149 PPI users, whereas 6798 were positioned in 2241 nonusers. Of these, 43 and 212 implants failed in users and nonusers, respectively (odds ratio: 2.91, 95% confidence interval: 2.06-4.11). The meta-analysis was performed using the statistical software Review Manager, and a fixed-effect model was used to obtain the odds ratio. The success rate of implants based on age, gender, smoking, and bone augmentation could be combined only from two studies, which revealed a considerable effect of these factors.

Conclusion

As far as the available evidence is considered, it seems as if the usage of PPI has a detrimental effect on the success of dental implants. This influence needs justification as none of the included studies segregated the data based on confounding factors. Hence, there is a need to conduct well-designed, prospective, randomized clinical trials with balanced confounding factors to derive a proper conclusion.

Potential proton pump inhibitor-related adverse effects

Proton pump inhibitors (PPIs) are one of the most common medications taken by patients worldwide. PPIs are used to treat acid-related disorders, including gastroesophageal reflux disease, peptic ulcer disease, Helicobacter pylori infection, and nonsteroidal anti-inflammatory drug/stress ulceration. For some of these diseases, long-term treatment is necessary. With such prolonged use, concern and investigation into potential adverse effects has increased. In addition, data are available regarding potential anticancer effects of PPIs, especially regarding solid tumors. The aim of this review is to assess the literature on PPIs with regard to common concerns, such as drug-drug interactions, the intestinal microbiome, dementia and central nervous system disease, and osteoporosis, as well as to highlight potential negative and positive impacts of the drug in cancer.

Revising Dietary Phosphorus Advice in Chronic Kidney Disease G3-5D

We summarize how practicing dietitians combined available evidence with clinical experience, to define revised dietary recommendations for phosphorus in chronic kidney disease G3-5D. As well as a review of the evidence base, 4 priority topics were reviewed. These were translated into 3 nutrient level recommendations: the introduction of some plant protein where phosphorus is largely bound by phytate; consideration of protein intake in terms of phosphorus load and the phosphorus to protein ratio; and an increased focus on avoiding phosphate additives. This review summarizes and interprets the available evidence in order to support the development of practical food-based advice for patients with chronic kidney disease.

Adverse Effects of Proton Pump Inhibitors-Evidence and Plausibility

Proton pump inhibitors (PPIs) have been increasingly used over the last decades and there are concerns about overuse and the numerous reported side-effects. It is uncertain whether associations between PPI use and potential side effects are causal. However, important evidence from experimental and mechanistic studies that could support a causal relationship may have been underestimated by epidemiologists and meta-analysists. In the current manuscript we review the combined epidemiological and mechanistic evidence of the adverse effects of PPI use.

Proton pump inhibitor intake negatively affects the osseointegration of dental implants: a retrospective study

Objectives

This study sought to investigate the association between the systemic intake of proton pump inhibitors (PPI) and the early failure of dental implants.

Materials and Methods

A retrospective cohort study involving 1,918 dental implants in 592 patients (69 implants in 24 PPI users and 1,849 implants in 568 nonusers, respectively) was conducted. The effect of PPI intake on the osseointegration of dental implants was evaluated using patient- and implant-level models.

Results

Among 24 PPI users, two patients experienced implant failure, one of whom had three and the other of whom had one failed implant, respectively. Thus, the rate of failure for this population was 8.3%. Separately, 11 nonusers each experienced one implant failure, and the failure rate for these patients was 1.9%. Fisher's exact test revealed statistically significant differences between PPI users and nonusers at the implant level (P=0.002) but failed to show any significance at the patient level (P=0.094). The odds of implant failure were 4.60 times greater among PPI users versus nonusers. Dental implants that were placed in patients using PPIs were found to be 4.30 times more likely to fail prior to loading.

Conclusion

The findings of this study suggest that PPI intake may be associated with an increased risk of early dental implant failure.

Dexlansoprazole and Esomeprazole Do Not Affect Bone Homeostasis in Healthy Postmenopausal Women

BACKGROUND & AIMS

Epidemiological studies have associated proton pump inhibitor (PPI) therapy with osteoporotic fractures, but it is not clear if PPIs directly cause osteoporosis. We evaluated the effect of dexlansoprazole and esomeprazole on bone turnover, bone mineral density (BMD), true fractional calcium absorption (TFCA), serum and urine levels of minerals, and levels of parathyroid hormone (PTH) in healthy postmenopausal women.

METHODS

We performed a prospective, multicenter, double-blind study of 115 healthy, postmenopausal women (45 to 75 years of age) from November 4, 2010, through August 7, 2014. Women were randomly assigned to groups given dexlansoprazole (60 mg), esomeprazole (40 mg), or placebo daily for 26 weeks. We measured plasma levels of procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide of type 1 collagen (CTX) at 0 (baseline), 13, and 26 weeks. Primary outcomes were percent change in P1NP and CTX between weeks 0 and 26. We also measured changes in serum and urine levels of mineral, BMD, PTH (all subjects), and TFCA (n = 30).

RESULTS

Between baseline and week 26, there were no significant within-group differences in markers of bone turnover; there was a nonsignificant increase in CTX levels in the dexlansoprazole group (0.12 ng/mL). The esomeprazole and dexlansoprazole groups had significantly increased levels of P1NP (18.2% and 19.2%, respectively) and CTX (22.0% and 27.4%, respectively) at week 26 compared with the placebo group, although these values remained within normal ranges. There were no statistically significant differences between groups in serum or urine levels of minerals, BMD, or PTH at week 26. PPI therapy did not reduce TFCA.

CONCLUSIONS

In a prospective study of postmenopausal women, we found significant increases in markers of bone turnover in women given PPI therapy compared with women given placebo, but levels remained within the normal reference range. We found no significant differences among groups in changes in BMD, PTH, serum or urine levels of minerals, or TFCA. Our findings indicate that 26 weeks of treatment with a PPI has no clinically meaningful effects on bone homeostasis. Clinicaltrials.gov no: NCT01216293.

Analysis of postmarketing safety data for proton-pump inhibitors reveals increased propensity for renal injury, electrolyte abnormalities, and nephrolithiasis

Proton pump inhibitors, PPIs, are widely prescribed and sold globally. Although initially intended for time-limited treatment of acute disorders, such as gastric ulcers and esophagitis, PPIs are now commonly used for prolonged durations and are considered safe for over the counter access. Recent studies have raised concern over associations between PPI use and acute kidney injury, chronic kidney disease, end-stage renal disease, and electrolyte abnormalities. The growing concern over potentially serious adverse drug reactions warrants an evaluation of post marketing surveillance data. In this study of over ten million FDA Adverse Event Reporting System records, we provided evidence of kidney injury and electrolyte imbalances in an alarming number of patients taking PPIs. Additionally, we assessed differences between specific PPIs and observed significant electrolyte and renal abnormalities for each individual drug with varying magnitudes.

Association of Vitamin D and Parathyroid Hormone With Barrett's Esophagus

BACKGROUND

Esophageal adenocarcinoma has been inversely associated with exposure to ultraviolet radiation. This could be because of vitamin D deficiency or hyperparathyroidism promoting gastroesophageal reflux disease (GERD) and Barrett's esophagus.

AIM

The aim of this study is to determine the association between parathyroid hormone (PTH) and vitamin D deficiency with GERD symptoms, erosive esophagitis, and Barrett's esophagus.

METHODS

We assayed banked serum for PTH and total 25-hydroxy vitamin D from a cross-sectional cohort. Logistic regression was performed to estimate the associations of vitamin D deficiency and hyperparathyroidism with GERD symptoms, erosive esophagitis, and Barrett's esophagus.

RESULTS

Sera from 605 men were assayed, including 150 with GERD, 216 with erosive esophagitis, 145 with Barrett's esophagus, and 174 normal subjects. Contrary to our hypothesis, we found a strong inverse association between Barrett's esophagus and hyperparathyroidism (odds ratio=0.516; 95% confidence interval=0.265, 1.01), and a trend toward an inverse association with vitamin D deficiency. We found no association between vitamin D deficiency or hyperparathyroidism with GERD symptoms or erosive esophagitis.

CONCLUSIONS

Contrary to our hypothesis, we found an inverse association between serum PTH and Barrett's esophagus. Validation of the finding and the mechanism of that association deserves further study.

Proton Pump Inhibitors, Histamine-2 Receptor Antagonists, and Hip Fracture Risk among Patients on Hemodialysis

BACKGROUND AND OBJECTIVES

An association between proton pump inhibitor (PPI) use and hip fracture risk has been described in the general population, where the primary causative hypothesis focuses on impaired gastrointestinal calcium absorption. The impact of acid suppressor use on hip fracture risk in a high-risk subset, patients with ESKD requiring hemodialysis, is unknown and could help further distinguish the reason for higher susceptibility among PPI users.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using the US Renal Data System, we identified all hip fracture events recorded between 2009 and 2014 among patients dependent on hemodialysis. Eligible cases were matched on index date with ten controls. We identified PPI and histamine-2 receptor antagonist use from Medicare Part D claims covering 3 years before the index date and stratified according to proportion of days covered by filled prescriptions. Using logistic regression with multiple imputation for missing data, we estimated unadjusted and multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

We studied 4551 cases and 45,510 controls. Patients were older, more likely to be female and white, and had shorter dialysis vintage; fewer were obese. A larger proportion of patients had any prior PPI (70% versus 63%) or histamine-2 receptor antagonist (25% versus 23%) use. Use of PPI was associated with higher risk of hip fracture (adjusted OR, 1.19; 95% CI, 1.11 to 1.28). This association remained within subgroups of low, moderate, and high PPI use, yielding adjusted ORs of 1.16 (95% CI, 1.06 to 1.27), 1.21 (95% CI, 1.11 to 1.31), and 1.19 (95% CI, 1.08 to 1.31), respectively.

CONCLUSIONS

Among patients with ESKD on hemodialysis, PPIs and not histamine-2 receptor antagonists were associated with hip fracture events.

Proton Pump Inhibitors: Risks and Rewards and Emerging Consequences to the Gut Microbiome

In recent years, proton pump inhibitors (PPIs) have been criticized for their various adverse interactions and side effects, creating a dilemma among practitioners regarding their use. Our goal is to review the proper use and possible side effects that might be caused by or associated with PPI use. Conclusions were drawn based on the evidence supporting or refuting short-term and long-term adverse events associated with PPI use. We also looked for the evidence regarding effects of PPIs on gut microbiota and their overall safety profile. Although there are significant discrepancies in the current literature regarding various adverse effects associated with PPI use, current data suggest that PPI use is not associated with an increased risk of bone fractures, community-acquired pneumonia, cardiovascular events, hypocalcemia, and gastric malignancies. A mild increased risk of vitamin B₁₂ deficiency and chronic kidney disease, and a moderate increase in the risk of rebound hypersecretion, small intestinal bacterial overgrowth, and enteric infections, including Clostridium difficile, has been noted with PPI therapy. PPI's link with dementia and spontaneous bacterial peritonitis is not clear and requires further investigation. When used appropriately, PPIs are safe medications and are associated with minimal side effects. A clear indication and potential short-term and long-term side effects should be considered before starting PPI therapy.

Evidence of Drug-Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update

The long-term use of prescription and over-the-counter drugs can induce subclinical and clinically relevant micronutrient deficiencies, which may develop gradually over months or even years. Given the large number of medications currently available, the number of research studies examining potential drug-nutrient interactions is quite limited. A comprehensive, updated review of the potential drug-nutrient interactions with chronic use of the most often prescribed medications for commonly diagnosed conditions among the general U.S. adult population is presented. For the majority of the interactions described in this paper, more high-quality intervention trials are needed to better understand their clinical importance and potential consequences. A number of these studies have identified potential risk factors that may make certain populations more susceptible, but guidelines on how to best manage and/or prevent drug-induced nutrient inadequacies are lacking. Although widespread supplementation is not currently recommended, it is important to ensure at-risk patients reach their recommended intakes for vitamins and minerals. In conjunction with an overall healthy diet, appropriate dietary supplementation may be a practical and efficacious way to maintain or improve micronutrient status in patients at risk of deficiencies, such as those taking medications known to compromise nutritional status. The summary evidence presented in this review will help inform future research efforts and, ultimately, guide recommendations for patient care.

Proton Pump Inhibitors: Are They a Real Threat to the Patient?

Background

Proton pump inhibitors are among the most frequently prescribed drugs in the world and are generally considered safe. However, there is growing concern regarding their safety.

Summary

A nonsystematic review of the current literature was performed regarding proton pump inhibitors and their adverse effects. Proton pump inhibitors seem to be associated with fundic gland polyp development (without clinical relevance) and Clostridium difficile infection. Also, in cirrhotic patients, their prescription should be carefully reviewed. Regarding their association with other enteric infections, micronutrient deficiency, dementia, and chronic kidney disease, current evidence is still of low quality, and further studies are needed.

Key Messages

Considering the current evidence, most patients with a clear clinical indication for proton pump inhibitor treatment should probably benefit from the maintenance of their treatment without significant adverse effects. However, higher-quality studies are needed to confirm or dismiss most of the proposed adverse effects.

Proton pump inhibitors: Risks of long-term use

Proton pump inhibitors are among the most commonly prescribed classes of drugs, and their use is increasing, in particular for long-term treatment, often being over-prescribed and used for inappropriate conditions. In recent years, considerable attention has been directed towards a wide range of adverse effects, and even when a potential underlying biological mechanism is plausible, the clinical evidence of the adverse effect is often weak. Several long-term side effects have been investigated ranging from interaction with other drugs, increased risk of infection, reduced intestinal absorption of vitamins and minerals, and more recently kidney damage and dementia. The most recent literature regarding these adverse effects and their association with long-term proton pump inhibitor treatment is reviewed, and the mechanisms through which these possible complications might develop are discussed.

A Review of the Novel Application and Potential Adverse Effects of Proton Pump Inhibitors

Proton pump inhibitors (PPIs) are known as a class of pharmaceutical agents that target H⁺/K⁺-ATPase, which is located in gastric parietal cells. PPIs are widely used in the treatment of gastric acid-related diseases including peptic ulcer disease, erosive esophagitis and gastroesophageal reflux disease, and so on. These drugs present an excellent safety profile and have become one of the most commonly prescribed drugs in primary and specialty care. Except for gastric acid-related diseases, PPIs can also be used in the treatment of Helicobacter pylori infection, viral infections, respiratory system diseases, cancer and so on. Although PPIs are mainly used short term in patients with peptic ulcer disease, nowadays these drugs are increasingly used long term, and frequently for a lifetime, for instance in patients with typical or atypical symptoms of gastroesophageal reflux disease and in NSAID or aspirin users at risk of gastrotoxicity and related complications including hemorrhage, perforation and gastric outlet obstruction. Long-term use of PPIs may lead to potential adverse effects, such as osteoporotic fracture, renal damage, infection (pneumonia and clostridium difficile infection), rhabdomyolysis, nutritional deficiencies (vitamin B12, magnesium and iron), anemia and thrombocytopenia. In this article, we will review some novel uses of PPIs in other fields and summarize the underlying adverse reactions.

The Risks and Benefits of Long-term Use of Proton Pump Inhibitors: Expert Review and Best Practice Advice From the American Gastroenterological Association

BACKGROUND & AIMS

The purpose of this review is to evaluate the risks associated with long-term use of proton pump inhibitors (PPIs), focusing on long-term use of PPIs for three common indications: gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and non-steroidal anti-inflammatory drug (NSAID) bleeding prophylaxis.

METHODS

The recommendations outlined in this review are based on expert opinion and on relevant publications from PubMed, EMbase, and the Cochrane library (through July 2016). To identify relevant ongoing trials, we queried clinicaltrials.gov. To assess the quality of evidence, we used a modified approach based on the GRADE Working Group. The Clinical Practice Updates Committee of the American Gastroenterological Association has reviewed these recommendations. Best Practice Advice 1: Patients with GERD and acid-related complications (ie, erosive esophagitis or peptic stricture) should take a PPI for short-term healing, maintenance of healing, and long-term symptom control. Best Practice Advice 2: Patients with uncomplicated GERD who respond to short-term PPIs should subsequently attempt to stop or reduce them. Patients who cannot reduce PPIs should consider ambulatory esophageal pH/impedance monitoring before committing to lifelong PPIs to help distinguish GERD from a functional syndrome. The best candidates for this strategy may be patients with predominantly atypical symptoms or those who lack an obvious predisposition to GERD (eg, central obesity, large hiatal hernia). Best Practice Advice 3: Patients with Barrett's esophagus and symptomatic GERD should take a long-term PPI. Best Practice Advice 4: Asymptomatic patients with Barrett's esophagus should consider a long-term PPI. Best Practice Advice 5: Patients at high risk for ulcer-related bleeding from NSAIDs should take a PPI if they continue to take NSAIDs. Best Practice Advice 6: The dose of long-term PPIs should be periodically reevaluated so that the lowest effective PPI dose can be prescribed to manage the condition. Best Practice Advice 7: Long-term PPI users should not routinely use probiotics to prevent infection. Best Practice Advice 8: Long-term PPI users should not routinely raise their intake of calcium, vitamin B12, or magnesium beyond the Recommended Dietary Allowance (RDA). Best Practice Advice 9: Long-term PPI users should not routinely screen or monitor bone mineral density, serum creatinine, magnesium, or vitamin B12. Best Practice Advice 10: Specific PPI formulations should not be selected based on potential risks.

Influence of proton pump inhibitors and histamine H2 receptor antagonists on serum phosphorus level control by calcium carbonate in patients undergoing hemodialysis: a retrospective medical chart review

Background

Hyperphosphatemia is one of the common complications in patients undergoing hemodialysis. Although calcium carbonate (CaC) is often used to control serum inorganic phosphorus level in dialysis patients, co-administration of gastric acid reducers (ARs) may interfere with the phosphate binding effect of CaC. We performed a retrospective medical chart review to study whether ARs attenuate the hypophosphatemic effect of CaC in patients undergoing hemodialysis.

Methods

One hundred and eight chronic hemodialysis patients receiving either CaC alone or CaC concomitant with one of the ARs (proton pump inhibitors and histamine H₂-receptor antagonists) were retrieved from the medical charts in Juntendo University Nerima Hospital. The patients were subdivided according to the interval between hemodialysis sessions (interdialysis interval of 48 or 72 h). A multivariate analysis was performed to identify clinical covariates associated with the variability of serum inorganic phosphorus levels. The study protocol was approved by the Institutional Review Board before the study was begun.

Results

Among patients on hemodialysis with a 72-h interdialysis interval, the magnitude of increase in serum inorganic phosphorus concentration in patients receiving CaC and AR was significantly greater than in those receiving CaC alone. While a similar trend was observed among patients with a 48-h interdialysis interval, the difference did not reach a significant level. A multivariate regression analysis revealed that concomitant administration of ARs with CaC and a longer interdialysis interval (72 h) were significantly and independently associated with the magnitude of increase in serum phosphorus concentration between dialysis sessions. No significant differences in albumin-corrected serum calcium concentrations and incidence of pathological fractures were observed between patients receiving CaC alone and those receiving CaC with ARs.

Conclusions

Concomitant use of ARs with CaC may attenuate the hypophosphatemic effect of CaC in patients undergoing chronic hemodialysis. When hemodialysis patients require prescription of ARs for the prevention of upper gastrointestinal mucosal diseases (such as peptic ulcer), it may be prudent to choose a phosphate binder other than CaC.

Dietary Sources of Zinc and Factors Affecting its Bioavailability

Zinc is one of the more ubiquitous of nutrients, being found in modest amounts in a large number of foods. Human evolution has undoubtedly shaped the needs for zinc to be absorbed from our beverages and foods of both animal and plant origin in the diet. Different environmental and ecological circumstances modify the amount of zinc that needs to become available to individuals of different regions. We use an acronym approach to review and understand the bioavailability of zinc. The biological availability of zinc can be limited by many factors intrinsic and extrinsic to the host, and it can be enhanced by few. Challenges remain in assessing the bioavailability of zinc compounds as fortificants and in developing strategies to improve the uptake of the metal by reducing phytate and tannin content of diets, either through food technology or plant genetics.

Omeprazole suppressed plasma magnesium level and duodenal magnesium absorption in male Sprague-Dawley rats

Hypomagnesemia is the most concerned side effect of proton pump inhibitors (PPIs) in chronic users. However, the mechanism of PPIs-induced systemic Mg²⁺ deficit is currently unclear. The present study aimed to elucidate the direct effect of short-term and long-term PPIs administrations on whole body Mg²⁺ homeostasis and duodenal Mg²⁺ absorption in rats. Mg²⁺ homeostasis was studied by determining the serum Mg²⁺ level, urine and fecal Mg²⁺ excretions, and bone and muscle Mg²⁺ contents. Duodenal Mg²⁺ absorption as well as paracellular charge selectivity were studied. Our result showed that gastric and duodenal pH markedly increased in omeprazole-treated rats. Omeprazole significantly suppressed plasma Mg²⁺ level, urinary Mg²⁺ excretion, and bone and muscle Mg²⁺ content. Thus, omeprazole induced systemic Mg²⁺ deficiency. By using Ussing chamber techniques, it was shown that omeprazole markedly suppressed duodenal Mg²⁺ channel-driven and Mg²⁺ channel-independent Mg²⁺ absorptions and cation selectivity. Inhibitors of mucosal HCO₃^- secretion significantly increased duodenal Mg²⁺ absorption in omeprazole-treated rats. We therefore hypothesized that secreted HCO₃^- in duodenum decreased luminal proton, this impeded duodenal Mg²⁺ absorption. Higher plasma total 25-OH vitamin D, diuresis, and urine PO₄^3- were also demonstrated in hypomagnesemic rats. As a compensatory mechanism for systemic Mg²⁺ deficiency, the expressions of duodenal transient receptor potential melastatin 6 (TRPM6), cyclin M4 (CNNM4), claudin (Cldn)-2, Cldn-7, Cldn-12, and Cldn-15 proteins were enhanced in omeprazole-treated rats. Our findings support the potential role of duodenum on the regulation of Mg²⁺ homeostasis.

Role of Proton Pump Inhibitors in Calcium Absorption, Bone Resorption, and Risk of Hip Fracture

Objective:

To review the influence of proton pump inhibitors (PPIs) on calcium absorption, bone remodeling, and fracture risk.

Data Sources:

A search via MEDLINE (1966–April 2007) was performed using the search terms proton pump inhibitors, omeprazole, calcium absorption, calcium malabsorption, bone resorption, and fracture risk.

Study Selection and Data Extraction:

English-language literature, including abstracts, preclinical and clinical trials, and review articles, were identified from the data sources and reviewed.

Data Synthesis:

Data on the effect of PPIs on calcium absorption are conflicting; however, the majority of data indicate that PPIs decrease intestinal calcium absorption, which could negatively affect bone strength. In particular, calcium carbonate may be more difficult to absorb in an environment with elevated pH due to PPI use. Data on the role of PPIs in osteoclast function are also conflicting, with one human study indicating decreased bone resorption due to inhibition of osteoclast function and another human study indicating no association between PPIs and osteoclast function. The risk of fracture with PPI use was evaluated in 2 studies, and both studies found an increased risk of fracture of 14–44% after PPI use.

Conclusions:

PPI use may increase a patient's risk of fracture. Additional studies are needed before causality can be established.

A Proton Pump Inhibitor's Effect on Bone Metabolism Mediated by Osteoclast Action in Old Age: A Prospective Randomized Study

Background/Aims

Proton pump inhibitors (PPIs) act by irreversibly binding to the H⁺-K⁺-ATPase of the proton pump in parietal cells and may possibly affect the vacuolar H⁺-ATPase in osteoclasts.

Methods

We investigated the effect of 8 weeks of PPI treatment on the parameters of bone turnover and compared PPI with revaprazan, which acts by reversibly binding to H⁺-K⁺-ATPase in proton pumps. This study was a parallel randomized controlled trial. For 8 weeks, either a PPI or revaprazan was randomly assigned to patients with gastric ulcers. The parameters of bone turnover were measured at the beginning of and after the 8-week treatment period.

Results

Twenty-six patients (PPI, n=13; revaprazan, n=13) completed the intention-to-treat analysis. After the 8-week treatment period, serum calcium and urine deoxypyridinoline (DPD) were increased in the PPI group (serum calcium, p=0.046; urine DPD, p=0.046) but not in the revaprazan group. According to multivariate linear regression analysis, age ≥60 years was an independent predictor for the changes in serum calcium and urine DPD.

Conclusions

In elderly patients, administering a PPI for 8 weeks altered bone parameters. Our study suggested that PPIs might directly alter bone metabolism via the vacuolar H⁺-ATPase in osteoclasts.

Proton pump inhibitor associated hypomagnasaemia - a cause for concern?

AIMS

In recent years, there have been a number of case reports of severe hypomagnesaemia associated with proton pump inhibitor (PPI) use, such that both the FDA and MHRA have issued drug safety warnings. They have recommended periodic serum magnesium testing in patients prescribed PPIs but provide no guidance on timing of these measurements.

METHODS

To our knowledge, we are the first to perform a prospective study to explore specifically proton pump inhibitor associated hypomagnesaemia (PPIAH). We followed 56 patients new to PPIs prospectively as well as a further 100 patients on long term PPIs cross-sectionally to identify what factors may be influencing the development of significant hypomagnesaemia.

RESULTS

For the prospective arm of the study, we measured serum magnesium levels prior to starting a PPI and again at regular intervals for the next 8 months. For the cross-sectional arm of the study we measured serum magnesium levels on patients on PPI therapy ranging from less than 1 year to over 5 years.

CONCLUSION

We found that, although there was a significant downward trend in serum magnesium levels in patients new to PPI therapy with time, clinically relevant hypomagnesaemia was not readily identifiable on regular blood testing. We did however identify patients on concurrent diuretic therapy as being at higher risk and so would recommend regular serum magnesium testing alongside their regular renal function monitoring on a more frequent basis such as annually.

Proton pump inhibitors and hypomagnesemia in the general population: a population-based cohort study

BACKGROUND

Proton pump inhibitor (PPI) use has been associated with hypomagnesemia in case reports and hospital-based cohort studies. Our objective was to determine whether PPI use is associated with hypomagnesemia in the general population and whether this is also found in histamine 2 receptor antagonist (H2RA) users.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

9,818 individuals from the general population (Rotterdam Study).

PREDICTOR

PPI use and H2RA use compared to no use.

OUTCOMES & MEASUREMENTS

Serum magnesium and hypomagnesemia (serum magnesium ≤ 1.44 mEq/L). Analyses were adjusted for age, sex, body mass index, kidney function, comorbid conditions, and alcohol and diuretic use.

RESULTS

Serum magnesium level was 0.022 mEq/L lower in PPI users (n=724; 95% CI, -0.032 to -0.014 mEq/L) versus those with no use. PPI use was associated with increased risk of hypomagnesemia (n=36; OR, 2.00; 95% CI, 1.36-2.93) compared to no use. Effect modification was found between the use of PPIs and loop diuretics; in participants using loop diuretics (n=270), PPI use was associated with a further increased risk of hypomagnesemia (n=5; OR, 7.22; 95% CI, 1.69-30.83) compared to no use. The increased risk with PPIs was only seen after prolonged use (range, 182-2,618 days; OR, 2.99; 95% CI, 1.73-5.15). Including dietary magnesium intake into the model did not alter results (available for 2,504 participants, including 231 PPI users). H2RA users (n=250) also had a lower serum magnesium level (-0.016 [95% CI, -0.032 to -0.002] mEq/L) and increased risk of hypomagnesemia (n=12; OR, 2.00; 95% CI, 1.08-3.72) compared to those with no use, but no interaction with loop diuretics.

LIMITATIONS

Cross-sectional analysis with single serum magnesium measurement.

CONCLUSIONS

PPI use is associated with hypomagnesemia in the general population. Prolonged PPI use and concomitant loop diuretic use are associated with a stronger risk increase. Similar but weaker associations were found in H2RA users, except for interaction with loop diuretics.

Zinc absorption by young adults from supplemental zinc citrate is comparable with that from zinc gluconate and higher than from zinc oxide

The water-soluble zinc salts gluconate, sulfate, and acetate are commonly used as supplements in tablet or syrup form to prevent zinc deficiency and to treat diarrhea in children in combination with oral rehydration. Zinc citrate is an alternative compound with high zinc content, slightly soluble in water, which has better sensory properties in syrups but no absorption data in humans. We used the double-isotope tracer method with (67)Zn and (70)Zn to measure zinc absorption from zinc citrate given as supplements containing 10 mg of zinc to 15 healthy adults without food and compared absorption with that from zinc gluconate and zinc oxide (insoluble in water) using a randomized, double-masked, 3-way crossover design. Median (IQR) fractional absorption of zinc from zinc citrate was 61.3% (56.6-71.0) and was not different from that from zinc gluconate with 60.9% (50.6-71.7). Absorption from zinc oxide at 49.9% (40.9-57.7) was significantly lower than from both other supplements (P < 0.01). Three participants had little or no absorption from zinc oxide. We conclude that zinc citrate, given as a supplement without food, is as well absorbed by healthy adults as zinc gluconate and may thus be a useful alternative for preventing zinc deficiency and treating diarrhea. The more insoluble zinc oxide is less well absorbed when given as a supplement without food and may be minimally absorbed by some individuals. This trial was registered at clinicaltrials.gov as NCT01576627.

Contemporary view of the clinical relevance of magnesium homeostasis

Magnesium is one of the most abundant cations in the body and is essential for a wide variety of metabolically important reactions. Serum magnesium concentration is regulated by the balance between intestinal absorption and renal excretion. Hypomagnesaemia is relatively common, with an estimated prevalence in the general population ranging from 2.5 to 15%. It may result from inadequate magnesium intake, increased gastrointestinal or renal loss or redistribution from extracellular to intracellular space. Drug-induced hypomagnesaemia, particularly related to proton-pump inhibitor (PPI) therapy, is being increasingly recognized. Although most patients with hypomagnesaemia are asymptomatic, manifestations may include neuromuscular, cardiovascular and metabolic features. Due to the kidney's ability to increase fractional excretion to nearly 100% when the renal magnesium threshold is exceeded, clinically significant hypermagnesaemia is uncommon, generally occurring only in the setting of renal insufficiency and excessive magnesium intake. Symptoms include hypotension, nausea, facial flushing, ileus and flaccid muscle paralysis. In most cases, simply withdrawing exogenous magnesium is sufficient to restore normal magnesium concentrations, although occasionally administration of intravenous calcium or even dialysis may be required.

The role of the gastrointestinal tract in calcium homeostasis and bone remodeling

While skeletal biology was approached in a rather isolated fashion in the past, an increasing understanding of the interplay between extraskeletal organs and bone remodeling has been obtained in recent years. This review will discuss recent advances in the field that have shed light on how the gastrointestinal tract and bone relate to each other. In particular, the importance of the GI tract in maintaining calcium homeostasis and skeletal integrity will be reviewed as impaired gastric acid production represents a major public health problem with possible implications for sufficient calcium absorption. Osteoporosis, the most prevalent bone disease worldwide, is caused not only by intrinsic defects affecting bone cell differentiation and function but also by a large set of extrinsic factors including hormonal disturbances, malnutrition, and iatrogenic drug application. Given the skeletal requirements of calcium, amino acids, and energy for bone turnover and renewal, it is not surprising that the gastrointestinal (GI) tract is of major importance for skeletal integrity.

A population-based case-control study: proton pump inhibition and risk of hip fracture by use of bisphosphonate

BACKGROUND

Studies on the risk of osteoporotic fractures related to the use of proton pump inhibitors (PPIs) have been inconsistent. One recent cohort study reported that there was an interaction between PPIs and bisphosphonates (BPs). Thus we performed a case-control study aimed at evaluating the risk of hip fractures related to PPIs and exploring the interaction between PPIs and BPs.

METHODS

A case-control study was performed using the Korean Health Insurance Review and Assessment Service database from 2005 January to 2006 June. The cases were all incident hip fractures identified from July 2005 to June 2006, and up to four controls were matched to each case by age, gender, and osteoporosis. Conditional logistic regression was used to calculate the adjusted odds ratio (aOR) and its 95 % confidence intervals.

RESULTS

A total of 24,710 cases were identified and 98,642 controls were matched to the cases. The aOR and its 95 % CI of hip fractures related to the use of PPIs was 1.34 (95 % CI 1.24-1.44). When the study participants were stratified according to BP use, the aOR was 1.30 (95 % CI 1.19-1.42) in BP non-users, which was significantly different from the 1.71 (95 % CI 1.31-2.23) of BP users. Only BP users showed a decreasing tendency toward fracture risk as exposure to PPI became less recent, and a trend of increasing risk with increasing cumulative doses.

CONCLUSIONS

Our results suggest that the mechanism for increased risk of hip fracture by PPIs may arise mainly from interaction of BP and PPIs.

[Long-term proton pump inhibitor therapy and osteoporosis. Is there a real danger?]

Proton pump inhibitors are widely used in the treatment of acid-related diseases because they are considered to be effective and safe. In the past 10 years the use of proton pump inhibitors increased by over three folds, which is not associated with the increased prevalence of acid-related diseases obviously. However, like any other drugs, they have potential side effects. In recent years many studies have been published about the correlation between long-term proton pump inhibitor therapy and the increase of bone fractures. Most studies showed that long-term proton pump inhibitor therapy moderately increased fracture risk. The underlying mechanisms of increased number of bone fractures are not clarified yet. However, chronic acid suppression caused by long-term proton pump inhibitor therapy may play a crucial role in decreased absorption of calcium and vitamin B12 and, therefore, indirectly affecting the bones resulting in a decrease of bone mineral density. The available data suggest that proton pump inhibitors should be used with caution in patients with increased risk of osteoporosis.

Omeprazole enhances the colonic expression of the Mg(2+) transporter TRPM6

Proton pump inhibitors (PPIs) are potent blockers of gastric acid secretion, used by millions of patients suffering from gastric acid-related complaints. Although PPIs have an excellent safety profile, an increasing number of case reports describe patients with severe hypomagnesemia due to long-term PPI use. As there is no evidence of a renal Mg²⁺ leak, PPI-induced hypomagnesemia is hypothesized to result from intestinal malabsorption of Mg²⁺. The aim of this study was to investigate the effect of PPIs on Mg ²⁺homeostasis in an in vivo mouse model. To this end, C57BL/6J mice were treated with omeprazole, under normal and low dietary Mg²⁺ availability. Omeprazole did not induce changes in serum Mg²⁺ levels (1.48 ± 0.05 and 1.54 ± 0.05 mmol/L in omeprazole-treated and control mice, respectively), urinary Mg²⁺ excretion (35 ± 3 μmol/24 h and 30 ± 4 μmol/24 h in omeprazole-treated and control mice, respectively), or fecal Mg²⁺ excretion (84 ± 4 μmol/24 h and 76 ± 4 μmol/24 h in omeprazole-treated and control mice, respectively) under any of the tested experimental conditions. However, omeprazole treatment did increase the mRNA expression level of the transient receptor potential melastatin 6 (TRPM6), the predominant intestinal Mg²⁺ channel, in the colon (167 ± 15 and 100 ± 7 % in omeprazole-treated and control mice, respectively, P < 0.05). In addition, the expression of the colonic H⁺,K⁺-ATPase (cHK-α), a homolog of the gastric H⁺,K⁺-ATPase that is the primary target of omeprazole, was also significantly increased (354 ± 43 and 100 ± 24 % in omeprazole-treated and control mice, respectively, P < 0.05). The expression levels of other magnesiotropic genes remained unchanged. Based on these findings, we hypothesize that omeprazole inhibits cHK-α activity, resulting in reduced extrusion of protons into the large intestine. Since TRPM6-mediated Mg²⁺absorption is stimulated by extracellular protons, this would diminish the rate of intestinal Mg²⁺ absorption. The increase of TRPM6 expression in the colon may compensate for the reduced TRPM6 currents, thereby normalizing intestinal Mg²⁺ absorption during omeprazole treatment in C57BL/6J mice, explaining unchanged serum, urine, and fecal Mg²⁺ levels.

Indications and safety of proton pump inhibitor drug use in patients with cancer

INTRODUCTION

Although the exact prevalence of proton pump inhibitor (PPI) use in cancer patients is not known, it is generally perceived to be widespread. PPIs are generally well tolerated and carry an excellent safety profile. However, increasing and longer term PPI use has raised concerns about the risk of pneumonia, bone fractures and enteric infections, and a possible interaction with clopidogrel that could increase the risk of cardiovascular events.

AREAS COVERED

We conducted a PubMed search of English language articles addressing the safety and adverse events associated with PPI use with particular emphasis in cancer patients.

EXPERT OPINION

PPIs, frequently used in cancer patients, are generally well tolerated and carry an excellent safety profile. PPI-induced acid suppression may increase the risk of Clostridium difficile or other enteric infections, nutritional deficiencies and community acquired pneumonia, all particularly important in cancer patients. The indications for PPI use in cancer patients should be carefully reviewed prior to use.

The effect of proton pump inhibitors on fracture risk: report from the Canadian Multicenter Osteoporosis Study

A large Canadian cohort was studied over 10 years to see if proton pump inhibitor (PPI) use increased the risk of sustaining a fragility fracture. We found an increased risk of fracture in individuals who used PPIs. The risk remained after controlling for other known fracture risk factors.

INTRODUCTION

Multiple retrospective studies have linked proton pump inhibitor use with increased risk of fragility fracture. We prospectively studied the association between PPI use and fracture in a large cohort over a 10-year period while controlling for known fracture risk factors.

METHODS

We studied 9,423 participants in the Canadian Multicenter Osteoporosis Study. The cohort was formed in 1995-1997 and followed for 10 years with monitoring for incident nontraumatic fracture and PPI use. Cox regression analyses were used to assess the association between PPI use and incident fracture risk.

RESULTS

PPI use, coded as a time-dependent variable, was associated with a shorter time to first nontraumatic fracture, hazard ratio (HR)=1.75 (95% confidence interval (CI) 1.41-2.17, p<0.001). After controlling for multiple risk factors, including femoral neck bone density, the association remained significant, HR=1.40 (95% CI 1.11-1.77, p=0.004). Similar results were obtained after controlling for bisphosphonate use, using PPI "ever" use, or when the outcome was restricted to hip fracture.

CONCLUSIONS

In this large prospective population-based cohort study, we found an association between PPI use and increased risk of fragility fracture. Although the increased risk found was modest, this finding is important, given the high prevalence of PPI use and the excess morbidity and mortality associated with osteoporosis-related fractures.

Proton pump inhibitors have no measurable effect on calcium and bone metabolism in healthy young males: a prospective matched controlled study

OBJECTIVES

Proton pump inhibitors (PPIs) are associated with an increased risk of bone fractures. This study sought to evaluate the effect of PPIs on biochemical markers of calcium and bone metabolism.

METHODS

Prospective matched controlled study involving healthy adult males (age 18-50years) suffering from frequent heartburn. Patients received standard-dose PPI for 12weeks and were matched by age with healthy controls. Blood studies were taken at 0, 1 and 3months for biochemical markers of mineral and bone metabolism. Two-way (time and PPI treatment) repeated measures analysis of variance (RM-ANOVA) and multiple linear regression were used for analysis.

RESULTS

A total of 58 participants (29 per group) completed the study. Mean age of participants was 33.2±7.5years. Baseline characteristics and biomarkers were similar for both groups except for higher BMI (28.6 vs. 25.6kg/m(2), p=0.008) and serum C-terminal cross linked telopeptides of type I collagen [CrossLaps, (300 vs. 228pg/ml, p=0.028)] in the PPI group. There was no difference in parathormone (PTH), ionized calcium, vitamin D, osteocalcin and CrossLaps between the PPI and control subjects (all non-significant; 2-way RM-ANOVA). Multiple linear regression modeling showed no effect of PPIs on any of the studied calcium or bone metabolism biomarkers.

CONCLUSION

PPI intake for 12weeks has no measurable effect on calcium or bone metabolism in healthy young males.

Gastric acid, calcium absorption, and their impact on bone health

Calcium balance is essential for a multitude of physiological processes, ranging from cell signaling to maintenance of bone health. Adequate intestinal absorption of calcium is a major factor for maintaining systemic calcium homeostasis. Recent observations indicate that a reduction of gastric acidity may impair effective calcium uptake through the intestine. This article reviews the physiology of gastric acid secretion, intestinal calcium absorption, and their respective neuroendocrine regulation and explores the physiological basis of a potential link between these individual systems.

Chronic proton pump inihibitor therapy and calcium metabolism

Proton pump inhibitors (PPIs) have been widely used since their introduction in the late 1980s because they are highly effective for acid-related conditions. However, some recent epidemiological studies have suggested a positive association between PPI therapy and the risk of osteoporotic fractures. The potential mechanisms underlying this association may be related to the physiologic effects of chronic acid suppression on calcium metabolism. First, chronic hypergastrinemia induced by PPI therapy may lead to parathyroid hyperplasia, resulting in increased loss of calcium from the bone. Second, profound gastric acid suppression may reduce the bioavailability of calcium for intestinal absorption. I will review the published evidence regarding these potential links and discuss their clinical implications.

Apical acidity decreases inhibitory effect of omeprazole on Mg(2+) absorption and claudin-7 and -12 expression in Caco-2 monolayers

Clinical studies reported hypomagnesaemia in long-term omeprazole usage that was probably due to intestinal Mg(2+) wasting. Our previous report demonstrated the inhibitory effect of omeprazole on passive Mg(2+) transport across Caco-2 monolayers. The present study aimed to identify the underlying mechanism of omeprazole suppression of passive Mg(2+) absorption. By using Caco-2 monolayers, we demonstrated a potent inhibitory effect of omeprazole on passive Mg(2+), but not Ca(2+), transport across Caco-2 monolayers. Omeprazole shifted the %maximum passive Mg(2+) transport-Mg(2+) concentration curves to the right, and increased the half maximal effective concentration of those dose-response curves, indicating a lower Mg(2+) affinity of the paracellular channel. By continually monitoring the apical pH, we showed that omeprazole suppressed apical acid accumulation. Neomycin and spermine had no effect on passive Mg(2+) transport of either control or omeprazole treated monolayers, indicating that omeprazole suppressed passive Mg(2+) transport in a calcium sensing receptor (CaSR)-independent manner. The results of western blot analysis showed that omeprazole significantly suppressed claudin (Cldn)-7 and -12, but not Cldn-2, expression in Caco-2 cells. By using apical solution of pH 5.5, 6.0, 6.5, and 7.0, we found that apical acidity markedly increased passive Mg(2+) transport, Mg(2+) affinity of the paracellular channel, and Cldn-7 and -12 expression in Caco-2 monolayers. Apical acidity abolished the inhibitory effect of omeprazole on passive Mg(2+) transport and Cldn-7 and -12 expression. Our results provided the evidence for the regulation of intestinal passive Mg(2+) absorption by luminal acidity-induced increase in Cldn-7 and -12 expression.

Modeling and simulation of the effect of proton pump inhibitors on magnesium homeostasis. 1. Oral absorption of magnesium

Prolonged use of proton pump inhibitors has reportedly caused rare clinically symptomatic hypomagnesemia. A review of the literature suggests PPI drugs may impair intestinal magnesium absorption. With the goal of preventing PPI-induced hypomagnesemia, an oral absorption-centric model was developed by referencing literature data. Our modeling with human data reveals that magnesium absorption is substantial in the distal intestine. We then perform simulations by referring to the reported reduction in mid to distal intestinal pH caused by one week of oral esomeprazole, and to reported reduction of the divalent cation-sensitive current when the carboxyl side chains of glutamic and aspartic residues in the binding channels of TRPM6/TRPM7 were neutralized. Our simulations reveal that short-term PPI therapy may cause a very small reduction (5%) in the serum magnesium level, which is qualitatively consistent with the reported 1% reduction in magnesium absorption following 1 week of omeprazole in humans. Simulations provide insight into the benefit of frequent but small dose of magnesium supplementation in maintaining the serum magnesium level when magnesium deficiency occurs.

Fracture risk and bone mineral density reduction associated with proton pump inhibitors

Many patients receive prolonged proton pump inhibitor (PPI) therapy for upper gastrointestinal disorders, but the long-term safety of PPIs, particularly increased risk of hip and nonhip fractures, has been questioned. To summarize the current literature on the risk of bone mineral density (BMD) reduction and fracture associated with PPI therapy, we conducted a literature search to identify all pertinent studies from 1980-February 2011. A total of 14 observational studies were included in this review. Most studies evaluated the risk of fracture associated with prolonged PPI exposure. Eight studies found an increased fracture risk at the hip, and five studies found an increased fracture risk at the spine associated with PPIs. Three studies showed reduction in fracture risk associated with PPIs after discontinuation for 1 month-1 year. Three studies evaluated the risk of BMD reduction associated with PPIs but did not find consistent changes in baseline or subsequent BMD. The current data suggest a modest increase in the risk of hip fracture and vertebral fracture associated with PPIs, although some studies showed conflicting results. Further studies will be needed to determine whether the increased risk of fracture is due to PPI exposure or residual confounding.

Effects of omeprazole consumption on serum levels of trace elements

PROJECT

Omeprazole is one of the most frequently prescribed drugs in patients with gastroesophageal reflux disease (GERD). It increases the gastric pH and this in turn may change the intestinal absorption of trace elements. This study was conducted to assess the effects of omeprazole consumption on the serum level of trace elements.

PROCEDURES

The studied subjects were selected from the list of patients referred to the gastroenterology department of 5 Azar hospital in Golestan province of Iran for whom omeprazole was prescribed by a gastroenterologist. Blood samples were obtained before (phase I) and after an eight-week period (phase II) of omeprazole consumption. Serum levels of trace elements were assessed by the photometric method.

RESULTS

Sixty seven patients were recruited of whom, 35.82% were males. There was no significant difference in serum levels of Fe, P, Ca and Cu between phases I and II. Serum concentration of Zn was significantly lower in phase II than I (P=0.02). The proportion of male patients with low Zn levels was significantly higher in phase II (50%) than I (16.7%) (P=0.01). We found no significant difference in the proportion of female patients with low Zn levels between phase I (37.2%) and phase II (27.9%).

CONCLUSIONS

We found no significant reduction in serum levels of Fe, P, Ca and Cu in phase II. However, our results showed that serum level of Zn was significantly lower after omeprazole consumption in males. So, nutritional supplement of Zn should be considered in male patients treated with omeprazole.