Increased Risk of Fractures and Use of Proton Pump Inhibitors in Menopausal Women: A Systematic Review and Meta-Analysis

Proton pump inhibitors (PPIs) can directly interfere with osteoclastic function, induce hypergastrinemia, and inhibit calcium absorption, leading to reduced bone mineral density (BMD), a measure of bone metabolism that may be associated with the risk of fractures. The current study involves a systematic review and meta-analysis aimed at assessing the relationship between prolonged use of PPI drugs and fractures in menopausal women. A systematic search and meta-analysis were performed on PubMed, Scopus, and Science Direct databases according to PRISMA guidelines. Two independent reviewers analyzed the articles. The five articles found in the databases, which met the eligibility criteria, covered participants who were menopausal women aged between 56 and 78.5 years, using or not using a PPI for a minimum of 12 months. All studies showed an increase in the rate of fractures related to using PPIs, as an outcome. Prolonged use of PPIs in menopausal women can affect bone metabolism and cause fractures. However, other factors, such as the use of other classes of drugs, obesity, low weight, poor diet, replacement hormones, and comorbidities, should also be considered for assessing the risk of fractures.

Omeprazole induces vascular remodeling by mechanisms involving xanthine oxidoreductase and matrix metalloproteinase activation

Proton pump inhibitors (PPI) are commonly used drugs that may increase the cardiovascular risk by mechanisms not entirely known. We examined whether the PPI omeprazole promotes vascular oxidative stress mediated by xanthine oxidoreductase (XOR) leading to activation of matrix metalloproteinases (MMPs) and vascular remodeling. We studied Wistar rats treated with omeprazole (or vehicle) combined with the XOR inhibitor allopurinol (or vehicle) for four weeks. Systolic blood pressure (SBP) measured by tail-cuff plethysmography was not affected by treatments. Omeprazole treatment increased the aortic cross-sectional area and media/lumen ratio by 25% (P < 0.05). Omeprazole treatment decreased gastric pH and induced vascular remodeling accompanied by impaired endothelium-dependent aortic responses (assessed with isolated aortic ring preparation) to acetylcholine (P < 0.05). Omeprazole increased vascular active MMP-2 expression and activity assessed by gel zymography and in situ zymography, respectively (P < 0.05). Moreover, omeprazole enhanced vascular oxidative stress assessed in situ with the fluorescent dye DHE and with the lucigenin chemiluminescence assay (both P < 0.05). All these biochemical changes caused by omeprazole were associated with increased vascular XOR activity (but not XOR expression assessed by Western blot) and treatment with allopurinol fully prevented them (all P < 0.05). Importantly, treatment with allopurinol prevented the vascular dysfunction and remodeling caused by omeprazole. Our results suggest that the long-term use of omeprazole induces vascular dysfunction and remodeling by promoting XOR-derived reactive oxygen species formation and MMP activation. These findings provide evidence of a new mechanism that may underlie the unfavorable cardiovascular outcomes observed with PPI therapy. Clinical studies are warranted to validate our findings.

Community pharmacy-based H. pylori screening for patients with uninvestigated dyspepsia

BACKGROUND

Helicobacter pylori is identified by the World Health Organization as a major risk factor of gastritis, peptic ulcer disease and gastric carcinomas. As point-of-care screening technology becomes more widely available, pharmacists are ideally suited to use this tool to screen patients with H. pylori infection.

PURPOSE

The objective of this study was to evaluate the feasibility of implementing point-of-care screening technology for H. pylori into community pharmacy practice and to assess the number of patients who are positively identified as a result of testing.

METHODS

Three pharmacies in Toronto, Ontario, offered H. pylori screening as part of their clinical programs. Pharmacists enrolled patients with symptoms of dyspepsia and/or receiving acid suppressant therapy for >6 weeks. Decision to screen was based on the Canadian Helicobacter Study Group Consensus (CHSG). Patients were screened using the Rapid Response H. pylori test.

RESULTS

Seventy-one patients were recruited, with a mean age of 46.3 years. Patients were ethnically diverse, with a significant proportion (59.2%) identified as being born outside of North America, including Asia (26.8%), Africa (9.9%), the Middle East (7%), Europe (9.9%) and South and Central America (5.6%). Overall, the detection rate of H. pylori infection was 21%. North Americans had the lowest incidence of an undiagnosed H. pylori infection (6.9%). Europeans (28.6%), Middle Easterners (20%) and Asians (21.1%) had a moderate incidence, followed by the highest prevalence in those of African descent (71.4%).

CONCLUSION

These results highlight the readiness of community pharmacists to adopt H. pylori screening into practice and to leverage this novel technology to positively identify and treat undiagnosed H. pylori infection. Can Pharm J (Ott) 2020;153:xx-xx.

Proton pump inhibitors have pH-dependent effects on the thermostability of the carboxyl-terminal domain of voltage-gated proton channel Hv1

The voltage-gated proton channel Hv1 is highly selective for H⁺ and is activated by membrane depolarization and pH gradient. An increased external and decreased internal pH opens the Hv1 channel. The intracellular C-terminal domain of Hv1 is responsible for channel dimerization, cooperative, and thermosensitive gating. Here, we found that proton pump inhibitors (PPIs) interact with the C-terminal domain of human Hv1. The interaction between PPIs and the C-terminal domain, which is pH-dependent, lowered the thermal and structural stability of the protein at pH 4, but enhanced the thermal and structural stability at pH 8. Furthermore, we investigated in vitro the interaction of PPIs with the C-terminal domain of Hv1 by fluorescence and micro-Raman spectra. Fluorescence quenching measurements revealed that the interaction between the C-terminal domain and PPIs is a mainly hydrophobic interaction. The micro-Raman spectra showed that PPIs did not form stable disulfide bonds with the unique thiol group within this domain (Cys²⁴⁹ residue). The preferential interaction of PPIs with the inactive form of Hv1 stabilizes the high pH inactive state of the C-terminal domain, indicating a mechanism by which PPIs might act explicitly on the stabilization of a closed state of the proton channel.

Long-term use of proton pump inhibitors, dose-response relationship and associated risk of ischemic stroke and myocardial infarction

BACKGROUND

Use of proton pump inhibitors (PPIs) has been associated with cardiovascular disease amongst patients not on antiplatelet therapy. The associations of PPI use, duration and dose, with risk of first-time ischemic stroke and myocardial infarction (MI) are poorly understood.

METHODS

All Danish individuals with no prior history of MI or stroke, who had an elective upper gastrointestinal endoscopy performed between 1997 and 2012, were identified from nationwide registries. We used multiple Poisson regression to test associations with current PPI use and its dose and used multiple cause-specific Cox regression and g-formula methods to analyze long-term use.

RESULTS

Amongst 214 998 individuals, during a median follow-up of 5.8 years, there were 7916 ischemic strokes and 5608 MIs. Current PPI exposure was associated with significantly higher rates of both ischemic stroke (Hazard ratio (HR) 1.13; 95% confidence interval (CI) 1.08-1.19) and MI (HR 1.31, CI 1.23-1.39) after adjusting for age, sex, comorbidities and concomitant medication. High-dose PPI was associated with increased rates of ischemic stroke (HR 1.31, CI 1.21-1.42) and MI (HR 1.43, CI 1.30-1.57). Histamine H2 receptor antagonists (H2RAs) use was not significantly associated with ischemic stroke (HR 1.02, CI 0.84-1.24) or MI (HR 1.15, CI 0.92-1.43). Long-term users of PPIs, compared with nonusers, had a 29% (CI 5%-59%) greater absolute risk of ischemic stroke and a 36% (CI 7%-73%) greater risk of MI within a 6-month period.

CONCLUSION

Use of PPIs was associated with increased risks of first-time ischemic stroke and MI, particularly amongst long-term users and at high doses.

Inappropriate prescribing of proton pump inhibitors in hospitalized patients

BACKGROUND

Proton pump inhibitors have numerous important side effects, yet they are prescribed for outpatients who do not have recognized indications. Less is known with respect to prescribing for inpatients.

OBJECTIVE

To determine the rate of inappropriate prescribing of protein pump inhibitors and to assess reasons why they are prescribed.

DESIGN AND PARTICIPANTS

The study was a retrospective review of administrative data for adult hospital patients discharged from the Medicine service of Denver Health (DH) and from the University HealthSystem Consortium (UHC) between January 1, 2008 and December 31, 2009.

MEASUREMENTS

Valid indications for proton pump inhibitors were sought from discharge diagnoses, prescription records, and, in a randomly selected group of patients from DH, from direct review of records.

RESULTS

Inclusion criteria were met by 9875 DH patients and 6,592,100 UHC patients; of patients receiving a proton pump inhibitor, 61% and 73%, respectively, did not have a valid indication. Increased rates of Clostridium difficile infection were found in both groups of patients receiving proton pump inhibitors. Chart reviews found valid indications for proton pump inhibitors in 19% of patients who did not have a valid indication on the basis of the administrative data, and "prophylaxis" was the justification for inappropriate prescribing in 56%.

CONCLUSION

Proton pump inhibitors are frequently inappropriately prescribed to Medicine inpatients who do not have a valid indication and this practice is associated with an increase in C. difficile infection. Interventions are needed to curtail this inappropriate prescribing practice.