Proton pump inhibitor omeprazole use is associated with low bone mineral density in maintenance haemodialysis patients

Use of proton pump inhibitors in dialysis patients: a double-edged sword?

Large cohort-based studies have shown that proton pump inhibitors (PPIs) are linked to rare but multiple and varied secondary events when used in the general population. Although clinicians accept the negative effects of PPIs on renal function, there is a lack of available data regarding the potential consequences of their use by dialysis patients in whom the risk of gastrointestinal bleeding is quite high. This review aims to highlight the risks and benefits of PPIs use in dialysis patients. To summarize, the benefit on the reduction of high digestive bleeding seems certain, but without any beneficial impact on overall survival. The impact on quality of life seems to be significant. The data on the occurrence of peritonitis during PPIs treatment are very contradictory. There is evidence regarding the occurrence of hypomagnesaemia in haemodialysis patients with PPIs; which may lead to increase bone fragility. New data show an increased cardiovascular risk and even a risk of death linked to the use of PPIs on dialysis. Several mechanisms of IPP toxicity are advanced to explain these findings.

Proton Pump Inhibitors and the Risk for Fracture at Specific Sites: Data Mining of the FDA Adverse Event Reporting System

Proton pump inhibitors (PPIs) are widely used to treat gastric acid-related disorders. Concerns have been raised about potential fracture risk, especially at the hip, spine and wrist. However, fracture risk at other bone sites has not been as well studied. We investigated the association between PPIs and specific fracture sites using an aggregated knowledge-enhanced database, the Food and Drug Administration Adverse Event Reporting System Data Mining Set (AERS-DM). Proportional reporting ratio (PRR) was used to detect statistically significant associations (signals) between PPIs and fractures. We analyzed both high level terms (HLT) and preferred terms (PT) for fracture sites, defined by MedDRA (Medical Dictionary for Regulatory Activities). Of PPI users reporting fractures, the mean age was 65.3 years and the female to male ratio was 3.4:1. Results revealed signals at multiple HLT and PT fracture sites, consistent for both sexes. These included fracture sites with predominant trabecular bone, not previously reported as being associated with PPIs, such as 'rib fractures', where signals were detected for overall PPIs as well as for each of 5 generic ingredients (insufficient data for dexlansoprazole). Based on data mining from AERS-DM, PPI use appears to be associated with an increased risk for fractures at multiple sites.

A Proton Pump Inhibitor in the Reformulation Setting: Bioequivalence and Potential Implications for Long-Term Safety

Proton pump inhibitors (PPIs) have become known for both their therapeutic effect and good safety profile. An application was submitted to the US Food and Drug Administration for approval of a reformulated PPI product that failed bioequivalence testing, but was submitted on the basis of the long history of PPI use as a "surrogate" for equivalence. This review evaluates the safety data for PPIs, discuss variability of pharmacokinetic parameters of PPIs in the reformulation setting, and potential implications of those changes for long-term safety.

An update on bone imaging and markers in chronic kidney disease

Bone disorders in chronic kidney disease (CKD) are associated with heightened risks of fractures, vascular calcification, poor quality of life and mortality compared to the general population. However, diagnosis and management of these disorders in CKD are complex and appreciably limited by current diagnostic modalities. Areas covered: Bone histomorphometry remains the gold standard for diagnosis but is not widely utilised and lacks feasibility as a monitoring tool. In practice, non-invasive imaging and biochemical markers are preferred to guide therapeutic decisions. Expert commentary: This review aims to summarize the risk factors for, and spectrum of bone disease in CKD, as well as appraise the clinical utility of dual energy X-ray densitometry, peripheral quantitative computed tomography, high-resolution peripheral quantitative computed tomography, and bone turnover markers.

Effects of Proton Pump Inhibitor Administration and Intake of a Combination of Yogurt and Galactooligosaccharides on Bone and Mineral Metabolism in Rats

The aim of this study was to investigate the effects of proton pump inhibitor (PPI), the most potent acid-suppressing drug, administration and intake of a combination of yogurt and galactooligosaccharides (YG) on bone and mineral metabolism in adult rats. Twelve-week-old male Wistar rats were divided into three groups: a control group fed the control diet with vehicle administration, a PPI group fed the control diet with PPI administration and a YG + PPI group fed the YG diet with PPI administration. All of the groups received their respective experimental diets and daily subcutaneous injection of the vehicle or PPI for 12 weeks. The PPI group showed significantly lower bone mineral density (BMD) of the femur and the lumbar vertebrae and serum fibroblast growth factor 23 (FGF23) and significantly higher phosphorus absorption and serum 1,25-dihydroxyvitamin D (1,25(OH)2D) than the control group, although PPI did not affect calcium absorption. The PPI + YG group showed significantly higher BMD and serum FGF23 and significantly lower phosphorus absorption and serum 1,25(OH)2D than the PPI group. Furthermore, the PPI + YG group showed higher calcium absorption than the control group. These results suggest that although PPI administration did not affect calcium absorption, it adversely affected BMD and influenced phosphorus metabolism in adult rats. Furthermore, the YG diet beneficially affected BMD and attenuated the effects of PPI administration on phosphorus metabolism.

Proton Pump Inhibitor Use and Magnesium Concentrations in Hemodialysis Patients: A Cross-Sectional Study

Magnesium concentration is a proven predictor of mortality in hemodialysis patients. Recent reports have indicated that proton pump inhibitor (PPI) use affects serum magnesium levels, however few studies have investigated the relationship between PPI use and magnesium levels in hemodialysis patients. This study aimed to clarify the association between PPI use and serum magnesium levels in hemodialysis patients. We designed this cross sectional study and included 1189 hemodialysis patients in stable condition. Associations between PPI and magnesium-related factors, as well as other possible confounders, were evaluated using a multiple regression model. We defined hypomagnesemia as a value < 2.0 mg/dL, and created comparable logistic regression models to assess the association between PPI use and hypomagnesemia. PPI use is associated with a significantly lower mean serum magnesium level than histamine 2 (H2) receptor antagonists or no acid-suppressive medications (mean [SD] PPI: 2.52 [0.45] mg/dL; H2 receptor antagonist: 2.68 [0.41] mg/dL; no acid suppressive medications: 2.68 [0.46] mg/dL; P = 0.001). Hypomagnesemia remained significantly associated with PPI (adjusted OR, OR: 2.05; 95% CI: 1.14–3.69; P = 0.017). PPI use is associated with an increased risk of hypomagnesemia in hemodialysis patients. Future prospective studies are needed to explore magnesium replacement in PPI users on hemodialysis.

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.

Prophylactic use of omeprazole associated with a reduced risk of peptic ulcer disease among maintenance hemodialysis patients

BACKGROUND

Patients undergoing maintenance hemodialysis (MHD) have a high prevalence of peptic ulcer disease (PUD). Omeprazole is a proton pump inhibitor with proven efficacy in the prevention and treatment of PUD. However, there is little data on the prophylactic use of omeprazole in reducing the risk of PUD among MHD patients.

METHODS

This prospective study included 93 patients undergoing MHD at Zen-Ho Dialysis Center between July 2008 and December 2009. Fifty-three patients were assigned to receive 20 mg of omeprazole daily for 18 months and 40 patients served as control. The Kaplan-Meier method was applied to calculate the cumulative incidence of PUD.

RESULTS

The per-protocol population comprised 85 patients (omeprazole group, 49; control group, 36). Both groups had similar baseline characteristics. The need for endoscopy was found to be significantly less (10.2 vs. 44.4%, p = 0.001) in the omeprazole group than in the control group. Dialysis patients in the omeprazole group required fewer blood transfusions and erythropoietin doses than did the control group patients. Kaplan-Meier analysis revealed a higher cumulative ulcer rate in the control group (log-rank test, p = 0.04). However, omeprazole did not reduce the risk of PUD in MHD patients on regular aspirin or warfarin.

CONCLUSIONS

We conclude that prophylactic use of omeprazole might be effective to lower the incidence of PUD among MHD patients without regular aspirin or warfarin use. Further large-scale controlled trials should be carried out to confirm our findings.

A dairy product fermented by lactobacilli cancels the adverse effects of hypochlorhydria induced by a proton pump inhibitor on bone metabolism in growing rats

The purpose of the present study is to investigate the effects of hypochlorhydria induced by proton pump inhibitor (PPI) administration and intake of a dairy product fermented by lactobacilli (DFL) on bone metabolism in growing rats. Male rats, aged 3 weeks, were divided into two groups: a control group fed a casein-based diet and a group fed a DFL-based diet. Each group was fed its respective experimental diets for 9 d. At day 5 of the feeding period, each group was divided into two subgroups: one that received a saline injection and one that received a PPI injection. Rats were subcutaneously administered saline or PPI for 5 d. Faecal Ca excretion was determined from day 6 to day 9. At the end of the experiment, plasma and femurs were collected. Administration of PPI significantly decreased bone mineral density (shown by X-ray computerised tomography) and bone strength (shown by a three-point bending test) in the control group. Plasma osteocalcin, type I collagen C-telopeptides, 1,25-dihydroxyvitamin D and parathyroid hormone concentrations were elevated by PPI administration in the control group. Faecal Ca excretion and urinary P excretion in the control group were remarkably increased by PPI administration. On the other hand, these adverse effects of PPI were not observed in the DFL group. These results suggest that hypochlorhydria-induced bone loss may result from high bone turnover induced by secondary hyperparathyroidism due to Ca malabsorption and that DFL intake cancels these adverse effects probably via improving Ca malabsorption in growing rats.

Proton pump inhibitors and risk of fractures: a meta-analysis of 11 international studies

BACKGROUND

Concerns have been raised about the risk of fractures with acid-suppressive medications, such as proton pump inhibitors and histamine(2)-receptor antagonists.

METHODS

This meta-analysis evaluated the association between proton pump inhibitor or histamine(2)-receptor antagonist use and fractures. We performed a systematic search of published literature (1970 to October 10, 2010) in MEDLINE, EMBASE, and other sources. Ten publications reporting 11 studies were considered eligible for analysis.

RESULTS

All studies were observational case-control or cohort studies and primarily evaluated older adults. The summary effect estimate for risk of hip fracture increased modestly among individuals taking proton pump inhibitors (relative risk [RR] 1.30, 95% confidence interval [CI], 1.19-1.43). There also was an increase in spine (RR 1.56, 95% CI, 1.31-1.85) and any-site fractures (RR 1.16, 95% CI, 1.04-1.30) among proton pump inhibitor users. These findings were similar in both men and women and after stratification by duration of use. In contrast, histamine(2)-receptor antagonist use was not significantly associated with increased risk of hip fracture (RR 1.12, 95% CI, 0.97-1.30).

CONCLUSION

In this meta-analysis of observational studies, proton pump inhibitors modestly increased the risk of hip, spine, and any-site fractures, whereas histamine(2)-receptor antagonists were not associated with fracture risk. The possibility of residual confounding cannot be excluded. Further skeletal evaluation should be considered for patients who are taking proton pump inhibitors and also at risk for osteoporotic fracture.

Association of long-term proton pump inhibitor therapy with bone fractures and effects on absorption of calcium, vitamin B12, iron, and magnesium

Proton pump inhibitors (PPI) are one of the most widely used classes of drugs. PPIs have a very favorable safety profile, and it is unusual for a patient to stop them because of side effects. However, with increasing numbers of patients chronically taking PPIs for gastroesophageal reflux disease and other common, persistent conditions, the long-term potential adverse effects are receiving increasing attention. An insufficiently studied area receiving much attention is the long-term effect of chronic acid suppression on the absorption of vitamins and nutrients. This increased attention results from the reported potential adverse effect of chronic PPI treatment leading to an increased occurrence of bone fractures. Interest in this area has led to examination of the effects of PPIs on calcium absorption/metabolism and numerous cohort, case-control, and prospective studies of their ability to affect bone density and cause bone fractures. In this article, these studies are systematically examined, as are studies of the effects of chronic PPI use on absorption of VB(12), iron, and magnesium. Studies in each area have led to differing conclusions, but when examined systematically, consistent results of several studies support the conclusion that long-term adverse effects on these processes can have important clinical implications.

Therapeutic effect of Streptococcus thermophilus CRL 1190-fermented milk on chronic gastritis

AIM: To investigate the potential therapeutic effect of exopolysaccharide (EPS)-producing Streptococcus thermophilus (S. thermophilus) CRL 1190 fermented milk on chronic gastritis in Balb/c mice.

METHODS: Balb/c mice were fed with the fermented milk for 7 d after inducing gastritis with acetyl-salicylic acid (ASA, 400 mg/kg body weight per day for 10 d). Omeprazole was included in this study as a positive therapeutic control. The gastric inflammatory activity was evaluated from gastric histology and inflammation score, number of interleukin-10 (IL-10), interferon-γ (INFγ) and tumor necrosis factor-α (TNF-α) cytokine-producing cells in the gastric mucosa, and thickness of the mucus layer.

RESULTS: Animals receiving treatment with the EPS-producing S. thermophilus CRL 1190 fermented milk showed a conserved gastric mucosa structure similar to that of healthy animals. Inflammation scores of the fermented milk-treated mice were lower than those of mice in the gastritis group (0.2 ± 0.03 vs 2.0 ± 0.6, P < 0.05). A marked decrease in INFγ⁺ (15 ± 1.0 vs 28 ± 1.2, P < 0.05) and TNF-α⁺ (16 ± 3.0 vs 33 ± 3.0, P < 0.05) cells and an increase in IL-10⁺ (28 ± 1.5 vs 14 ± 1.3, P < 0.05) cells compared to the gastritis group, was observed. Also, an increase in the thickness of the mucus gel layer (2.2 ± 0.6 vs 1.0 ± 0.3; 5.1 ± 0.8 vs 1.5 ± 0.4 in the corpus and antrum mucosa, respectively, P < 0.05) compared with the gastritis group was noted. A milk suspension of the purified EPS from S. thermophilus CRL1190 was also effective as therapy for gastritis.

CONCLUSION: This study suggests that fermented milk with S. thermophilus CRL 1190 and/or its EPS could be used in novel functional foods as an alternative natural therapy for chronic gastritis induced by ASA.

Hypochlorhydric stomach: a risk condition for calcium malabsorption and osteoporosis?

Malabsorption of dietary calcium is a cause of osteoporosis. Dissolution of calcium salts (e.g. calcium carbonate) in the stomach is one step in the proper active and passive absorption of calcium as a calcium ion (Ca(2+)) in the proximal small intestine. Stomach acid markedly increases dissolution and ionization of poorly soluble calcium salts. If acid is not properly secreted, calcium salts are minimally dissolved (ionized) and, subsequently, may not be properly and effectively absorbed. Atrophic gastritis, gastric surgery, and high-dose, long-term use of antisecretory drugs markedly reduce acid secretion and may, therefore, be risk conditions for malabsorption of dietary and supplementary calcium, and may thereby increase the risk of osteoporosis in the long term.