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

Monitoring of serum magnesium levels during long-term use of proton pump inhibitors in elderly japanese patients: is it really necessary or not?

BACKGROUND

Long-term use of proton pump inhibitors (PPIs) has been found to significantly lower serum magnesium levels in patients in the USA and Europe. The package inserts of PPIs in these countries clearly state that healthcare professionals should consider monitoring magnesium levels prior to initiation of PPI treatment and periodically thereafter. However, the package inserts of PPIs in Japan do not clearly mention the monitoring of magnesium levels. In this study, we evaluated the relationship between long-term use of PPIs and the lower serum magnesium concentrations in elderly Japanese patients.

METHODS

Using a retrospective observational approach, a total of 264 Japanese outpatients were included in the study. Patients over the age of 75 years were considered elderly. Serum magnesium levels of the patients were measured in units of 0.1 mg/dL between January 2016 and June 2022 at the Higo Internal Medicine Clinic and Ai Pharmacy in Kyoto, Japan.

RESULTS

Four of the 264 eligible patients were diagnosed with hypomagnesemia. Three were PPI non-users, and one was a PPI user. Serum magnesium concentrations were significantly lower in PPI users (n = 47) than in non-users (n = 85; 2.1 ± 0.2 vs. 2.2 ± 0.3 mg/dL, p < 0.05) in the 132 elderly patients. Comorbidity included diabetes mellitus in both PPI users (23.4%) and non-users (57.6%) and hyperlipidemia in both PPI users (61.7%) and non-users (41.2%).

CONCLUSION

PPIs are commonly used oral drugs for elderly patients. There was an association between the long-term use of PPIs and lower serum magnesium concentrations in elderly patients. Although the difference in the decrease in serum magnesium concentrations was within the normal range of serum magnesium levels, health care professionals should consider monitoring serum magnesium levels periodically in elderly patients receiving long-term PPIs.

Magnesium exposure increases hip fracture risks in patients with chronic kidney disease: a population-based nested case-control study

This population-based study demonstrates a strong link between Mg-containing antacid exposure and hip fracture risk in nondialysis CKD and dialysis patients. As an Mg-containing antacid, MgO is also commonly used as a stool softener, which can be effortlessly replaced by other laxatives in CKD patients to maintain bone health.

PURPOSE

Bone fracture is a severe complication in chronic kidney disease (CKD) patients, leading to disability and reduced survival. In CKD patients, blood magnesium (Mg) concentrations are usually above the normal range due to reduced kidney excretion of Mg. The present study examines the association between Mg-containing antacid exposure and the risk of hip fracture of CKD patients.

METHODS

In this nationwide nested case-control study, we enrolled 44,062 CKD patients with hip fracture and 44,062 CKD matched controls, among which the mean age was 77.1 years old, and 87.9% was nondialysis CKD.

RESULTS

As compared to non-users, Mg-containing antacid users were significantly more likely to experience hip fracture (adjusted odds ratio (OR) 1.36, 95% CI, 1.32 to 1.41; p < 0.001). Subgroup analysis showed that such risk exists in both nondialysis CKD patients and long-term dialysis patients. In contrast, aluminum or calcium-containing-antacid use did not reveal such association. Next, we examined the influence of Mg-containing antacid dosage on hip fracture risk, the adjusted ORs in the first quartile (Q1), Q2, Q3, and Q4 were 1.20 (95% CI, 1.15 to 1.25; p < 0.001), 1.35 (95% CI, 1.30 to 1.41; p < 0.001), 1.49 (95% CI, 1.43 to 1.56; p < 0.001), and 1.54 (95% CI, 1.47 to 1.61; p < 0.001), respectively, showing that such risk exists regardless of the antacid dosage. A receiver operating characteristic curve analysis demonstrated that the best cutoff value of the exposed Mg dose to discriminate the hip fracture is 532 mEq during the follow-up period.

CONCLUSION

This population-based study demonstrates a strong link between Mg-containing antacid exposure and the hip fracture risk in both nondialysis CKD and dialysis patients.

Proton pump inhibitor therapy and risk of knee replacement surgery: a general population-based cohort study

OBJECTIVE

Proton pump inhibitors (PPIs) are among the most commonly used medications for patients with osteoarthritis (OA). Various types of PPIs have different impacts on lowering serum magnesium level that may affect knee OA progression. We aimed to compare the risk of clinically relevant endpoint of knee replacement (KR) among initiators of five different PPIs with that among histamine-2 receptor antagonist (H2RA) initiators.

DESIGN

Among patients with knee OA (≥50 years) in The Health Improvement Network database in the UK we conducted five sequential propensity-score matched cohort studies to compare the risk of KR over 5-year among patients who initiated omeprazole (n = 2,672), pantoprazole (n = 664), lansoprazole (n = 3,747), rabeprazole (n = 751), or esomeprazole (n = 827) with those who initiated H2RA.

RESULTS

The prevalence of PPI prescriptions among participants with knee OA increased from 12.7% in 2000-44.0% in 2017. Two-hundred-and-seventy-four KRs (30.8/1,000 person-years) occurred in omeprazole initiators and 230 KRs (25.4/1,000 person-years) in H2RA initiators. Compared with H2RA initiators, the risk of KR was 21% higher in omeprazole initiators (hazard ratio [HR] = 1.21,95% confidence interval [CI]:1.01-1.44). Similar results were observed when pantoprazole use was compared with H2RA use (HR = 1.38,95%CI:1.00-1.90). No such an increased risk of KR was observed among lansoprazole (HR = 1.06,95%CI:0.92-1.23), rabeprazole (HR = 0.97,95%CI:0.73-1.30), or esomeprazole (HR = 0.83,95%CI:0.60-1.15) initiators compared with that among H2RA initiators.

CONCLUSIONS

In this population-based cohort study, initiation of omeprazole or pantoprazole use was associated with a higher risk of KR than initiation of H2RA use. This study raises concern regarding an unexpected risk of omeprazole and pantoprazole on accelerating OA progression.

Higher Soluble ACE2 Levels and Increased Risk of Infection-Related Hospitalization in Patients on Maintenance Hemodialysis

Background

Angiotensin-converting enzyme 2 (ACE2) works as an endogenous counter-regulator of the renin-angiotensin system, which has pivotal roles in preventing both cardiovascular disease (CVD) and inflammation. In general populations, higher plasma soluble ACE2 levels were reported to be associated with increased risks of all-cause death and major CVD. Because infections are fatal in patients on maintenance hemodialysis, we aimed to explore whether soluble ACE2 levels are associated with an increased risk of infection-related hospitalization in these patients.

Methods

Using data from a prospective, multicenter, cohort study conducted in Tokyo, Japan, we performed a post-hoc analyses of 724 clinically stable patients on maintenance hemodialysis. We measured baseline serum soluble ACE2 levels and assessed potential determinants of its with infection-related hospitalization as a primary outcome as well as all-cause death and CVD as secondary outcomes using a Cox proportional hazards model.

Results

The soluble ACE2 level (median, 0.16 ng/ml; interquartile range, 0.07–0.57 ng/ml) showed a weak negative association with age. During a median follow-up of 39 months, 106 patients (14.6%) were hospitalized with infectious diseases. Compared with the lower half of soluble ACE2 levels, the higher half was associated with an increased risk of infection-related hospitalization (hazard ratio, 1.57; 95% confidence interval, 1.02–2.41) with adjustment by other risk factors. On the other hand, there were no significant associations between soluble ACE2 and risks of all-cause death and CVD.

Conclusion

Higher soluble ACE2 levels may associate with an increased risk of infection-related hospitalization in patients on maintenance hemodialysis.

Fibroblast growth factor 23 is independently associated with renal magnesium handling in patients with chronic kidney disease

BACKGROUND

Disturbances in magnesium homeostasis are common in patients with chronic kidney disease (CKD) and are associated with increased mortality. The kidney is a key organ in maintaining normal serum magnesium concentrations. To this end, fractional excretion of magnesium (FEMg) increases as renal function declines. Despite recent progress, the hormonal regulation of renal magnesium handling is incompletely understood. Fibroblast Growth Factor 23 (FGF23) is a phosphaturic hormone that has been linked to renal magnesium handling. However, it has not yet been reported whether FGF23 is associated with renal magnesium handling in CKD patients.

METHODS

The associations between plasma FGF23 levels, plasma and urine magnesium concentrations and FEMg was investigated in a cross-sectional cohort of 198 non-dialysis CKD patients undergoing renal biopsy.

RESULTS

FGF23 was significantly correlated with FEMg (Pearson's correlation coefficient = 0.37, p<0.001) and urinary magnesium (-0.14, p=0.04), but not with plasma magnesium. The association between FGF23 and FEMg remained significant after adjusting for potential confounders, including estimated glomerular filtration rate (eGFR), parathyroid hormone and 25-hydroxyvitamin D.

CONCLUSIONS

We report that plasma FGF23 is independently associated with measures of renal magnesium handling in a cohort of non-dialysis CKD patients. A potential causal relationship should be investigated in future studies.

Association between serum magnesium levels and abdominal aorta calcification in patients with pre-dialysis chronic kidney disease stage 5

BACKGROUND

Several studies have revealed the relationship between serum magnesium levels and vascular calcification in chronic kidney disease patients. Despite excellent predictability of abdominal aorta calcification for cardiovascular disease events, the relationship between serum magnesium levels and abdominal aorta calcification, as evaluated by quantitative methods, in pre-dialysis patients remains unclear. This study aimed to determine the abdominal aorta calcification volume using computerized tomography and its association with serum magnesium levels in pre-dialysis chronic kidney disease stage 5 patients.

METHODS

This single-center cross-sectional study included 100 consecutive patients with pre-dialysis chronic kidney disease stage 5 between January 2016 and May 2020 at Aichi Medical University Hospital, Japan. The relationships between serum magnesium levels and the abdominal aorta calcification volume were assessed using multiple linear regression models after adjusting for clinically relevant factors. We also assessed clinical factors that affect serum magnesium levels.

RESULTS

The mean serum magnesium level was 2.0 mg/dL (interquartile range, 1.8 to 2.3). Multivariate analyses revealed that a higher serum magnesium level (stand. β = -0.245, p = 0.010) was significantly associated with a reduced abdominal aorta calcification volume, and that a history of cardiovascular disease (stand. β = 0.3792, p < 0.001) and older age (stand. β = 0.278, p = 0.007) were significantly associated with an increased abdominal aorta calcification volume. Moreover, multivariate analysis showed that the use of proton pump inhibitor or potassium-competitive acid blocker was significantly associated with lower serum magnesium levels (stand. β = -0.246, p = 0.019).

CONCLUSIONS

The present study revealed that the higher Mg level was significantly associated with lower volume of abdominal aorta calcification in pre-dialysis chronic kidney disease stage 5 patients. Further studies should be undertaken to determine the appropriate magnesium level to suppress vascular calcification.

High serum magnesium levels are associated with favorable prognoses in diabetic hemodialysis patients, retrospective observational study

Background

Recent studies have found hypomagnesemia is linked to a heightened risk of cardiovascular events and mortality in hemodialysis (HD) patients; however, the level of serum magnesium (s-Mg) necessary for promoting overall health in these patients and the effects of s-Mg in diabetes HD patients remains to be clarified.

Methods

HD outpatients (n = 148 under, age ≤ 70 y) were followed over a 6-y period. They were divided into four groups according to their average s-Mg during the first year (L; low level, H; high level) and if they had DM or not (non-DM). The endpoint was mortality and hospitalization for decline of Activities of Daily Living (death/hospitalization). A receiver operating characteristics curve was used in diagnostic tests to identify s-Mg associated with this endpoint. Kaplan–Meier, log-rank test, and a Cox proportional hazards model were used to evaluate prognoses. Fisher's exact test and multiple regressions examined the causes of the endpoints between the four groups and the factors predictive of s-Mg.

Results

s-Mg at 2.7 mg/dL was associated with death/hospitalization. The 5-y survival rate was 38.1%, 86.7%, 73.2% and 87.5%, in the DM/Mg(L), DM/Mg(H), non-DM/Mg(L) and non-DM/Mg(H) groups, respectively (P < 0.001). The Cox proportional hazards model showed significantly lower risk in other groups compared with that in the DM/Mg(L) group [DM/Mg(H); hazard ratio (HR): 0.22, 95% confidence interval (CI): 0.05–0.97, P = 0.046, non-DM/Mg(L); HR: 0.32, 95% CI: 0.15–0.68, P = 0.003, non-DM/Mg(H); HR: 0.17, 95% CI: 0.06–0.44, P < 0.001]. The frequency of the different causes of the endpoints for each group was not significant; s-Mg only associated with age in the DM group.

Conclusions

s-Mg greater than 2.7 mg/dL associated with a favorable prognosis in HD patients with DM, suggesting that s-Mg is a factor independent of diabetes.

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.

Dysfunctional ABCG2 gene polymorphisms are associated with serum uric acid levels and all-cause mortality in hemodialysis patients

Dysfunctional variants of ATP-binding cassette transporter subfamily G member 2 (ABCG2), a urate transporter in the kidney and intestine, are the major causes of hyperuricemia and gout. A recent study found that ABCG2 is a major transporter of uremic toxins; however, few studies have investigated the relationship between ABCG2 gene polymorphisms and mortality. This prospective cohort study of 1214 hemodialysis patients investigated the association between serum uric acid levels and ABCG2 genotype and mortality. Genotyping of dysfunctional ABCG2 variants, Q126X (rs72552713) and Q141K (rs2231142), was performed using the patients’ DNA. During the study period, 220 patients died. Lower serum uric acid levels were associated with higher mortality (hazard ratio [HR] 1.89, 95% confidence interval [CI] 1.14–3.10, P ≤ 0.001). ABCG2 dysfunction, estimated by genetic variants, had a significant positive association with serum uric acid levels (full function: 7.4 ± 1.2 mg/dl, 3/4 function: 7.9 ± 1.3 mg/dl, 1/2 function: 8.2 ± 1.4 mg/dl, ≤ 1/4 function: 8.7 ± 1.3 mg/dl, P ≤ 0.001). This association remained significant on multiple regression analysis. The Cox proportional hazard analysis indicated that the ABCG2 ≤ 1/4 function type was significantly associated with higher mortality (HR 6.66, 95% CI 2.49 to 17.8, P ≤ 0.001) than the other function types. These results showed that ABCG2 plays a physiologically important role in uric acid excretion, and that ABCG2 dysfunction is a risk factor for mortality in hemodialysis patients.

A questionnaire on prescription patterns of proton pump inhibitors for hemodialysis patients in Japan

BACKGROUND

Proton pump inhibitors (PPIs) are widely used in the general population often without an endpoint. The practice of prescribing PPIs in the hemodialysis (HD) population is unknown. Thus, we aimed to identify the practice pattern related to PPI prescription for HD patients in Japan through a questionnaire survey.

METHODS

We conducted a questionnaire survey for physicians engaged in dialysis practice through email. An email was sent to physicians listed in the Japanese Society of Nephrology (JSN) and iHOPE International registry.

RESULTS

We received 187 physicians' answers. One-hundred twelve (60%) physicians would prefer to continuously prescribe PPIs after 8 weeks of treatment for peptic ulcer (PU) or gastroesophageal reflux disease (GERD). The main reason for continuous PPI prescription was the concern for recurrence of PU or GERD. Approximately 20% of physicians responded that they were not accustomed to de-prescribing PPIs for PU or GERD. The reason for PPI de-prescription was the concern for side effects or insurance adaptation period. Even in cases wherein PPIs were prescribed for uncertain reasons, 42% physicians would continuously prescribe PPIs. Most physicians (82%) who answered about stopping PPIs regarded HD patients as a high-risk group for PU.

CONCLUSIONS

PPI prescription is often continued in HD patients. De-prescription is not a common practice in Japan. It remains unclear whether discontinuation of PPIs should be recommended in hemodialysis patients who have a high risk of gastrointestinal ulcer. Yet, considering the side effects and polypharmacy in the HD population, more discussions on preferable de-prescription of PPIs are needed.

Use of proton pump inhibitors is associated with an increase in adverse cardiovascular events in patients with hemodialysis: Insight from the kids registry

BACKGROUND

Proton pump inhibitors (PPIs) are known to increase the risk of mortality and cardiovascular events in the general population. However, in patients with maintenance hemodialysis, PPI effects are under investigated.

METHODS

We analyzed the risk of PPIs for cardiovascular events using the Kagoshima Dialysis (KIDS) registry, a prospective, multicenter, observational study in patients with maintenance hemodialysis in Japan.

RESULTS

In all, 531 patients were enrolled from June 2015 to December 2018. One-year follow-up data were available for 376 patients (Use of PPIs at baseline (PPI group): 217 patients and without PPIs (No PPI group): 159 patients). The incidence of a composite outcome (all-cause mortality, non-fatal myocardial infarction, or non-fatal stroke) was higher in patients in the PPI group than the No PPI group (15.2% vs. 4.4%; hazard ratio (HR): 3.65, 95% confidence interval (CI): 1.61-8.23, P = 0.002). In the multivariate analysis, even after adjustment for covariates, the use of PPIs was an independent risk factor for a composite outcome (HR: 2.38, 95% CI: 1.02-5.54, P = 0.045). We performed propensity score matching analysis as a sensitivity analysis, showing a consistent result. The incidence of bleeding showed no difference between the two groups (15.7% vs. 11.3%; HR: 1.46, 95% CI: 0.83-2.59, P = 0.19).

CONCLUSIONS

These results indicate that the use of PPIs in patients with maintenance hemodialysis might increase mortality and cardiovascular events without decreasing the risk of bleeding. Therefore, it should always be analyzed if a patient truly needs PPIs.

Proton pump inhibitors and hypomagnesemia: A meta-analysis of observational studies

BACKGROUND

Previous meta-analyses have suggested that there might be an association between the use of proton pump inhibitors (PPIs) and the development of hypomagnesemia, although the conclusions were no definitive.

METHODS

To provide an update on this topic, we performed a meta-analysis of all observational studies that examined the association between the use of PPIs and the development of hypomagnesemia. A literature search was conducted in MEDLINE, Scopus and Cochrane Central Register of Controlled Trials (January 1970 to June 2018) to identify observational studies that examined the association between the use of PPIs and the incidence and prevalence of hypomagnesemia.

STUDY ELIGIBILITY CRITERIA

In the absence of randomized controlled trials, we focused primarily on observational studies, including cross-sectional, case-control, retrospective, and prospective cohort studies. There was no limitation on sample size or study duration. Random-effect models meta-analyses were used to compute pooled unadjusted and adjusted odds ratios (ORs) for binary variables.

RESULTS

Sixteen observational studies were identified, including 13 cross-sectional studies, 2 case-control studies, and 1 cohort study, with a total of 131,507 patients. The pooled percentage of PPI users was 43.6% (95% confidence interval [CI] 25.0%, 64.0%). Among PPI users, 19.4% (95% CI 13.8%, 26.5%) had hypomagnesemia compared to 13.5% (95% CI 7.9%, 22.2%) among nonusers. By meta-analysis, PPI use was significantly associated with hypomagnesemia, with a pooled unadjusted OR of 1.83 (95% CI 1.26, 2.67; P = .002) and a pooled adjusted OR of 1.71 (95% CI 1.33, 2.19; P < .001). In subgroup analyses, high-dose PPI use was associated with higher odds for hypomagnesemia relative to low-dose PPI use (pooled adjusted OR 2.13; 95% CI 1.26, 3.59; P = .005).

CONCLUSION

Our findings are in support of the results of the previous meta-analyses. Furthermore, we found a dose-response between the PPI use and development of hypomagnesemia.

Proton Pump Inhibitors and the Kidney: Implications of Current Evidence for Clinical Practice and When and How to Deprescribe

Proton pump inhibitors (PPIs), long thought to be safe, are associated with a number of nonkidney adverse health outcomes and several untoward kidney outcomes, including hypomagnesemia, acute kidney injury, acute interstitial nephritis, incident chronic kidney disease, kidney disease progression, kidney failure, and increased risk for all-cause mortality and mortality due to chronic kidney disease. PPIs are abundantly prescribed, rarely deprescribed, and frequently purchased over the counter. They are frequently used without medical indication, and when medically indicated, they are often used for much longer than needed. In this In Practice review, we summarize evidence linking PPI use with adverse events in general and adverse kidney outcomes in particular. We review the literature on the association of PPI use and risk for hypomagnesemia, acute kidney injury, acute interstitial nephritis, incident chronic kidney disease, kidney disease progression, end-stage kidney disease, and death. We provide an assessment of how this evidence should inform clinical practice. We review the impact of this evidence on patients' perception of risk, synthesize PPI deprescription literature, and provide our recommendations on how to approach PPI use and deprescription.

Low gut microbiota diversity and dietary magnesium intake are associated with the development of PPI-induced hypomagnesemia

Proton pump inhibitors (PPIs) are used by millions of patients for the treatment of stomach acid-reflux diseases. Although PPIs are generally considered safe, about 13% of the users develop hypomagnesemia. Despite rising attention for this issue, the underlying mechanism is still unknown. Here, we examine whether the gut microbiome is involved in the development of PPI-induced hypomagnesemia in wild-type C57BL/6J mice. After 4 wk of treatment under normal or low dietary Mg²⁺ availability, omeprazole significantly reduced serum Mg²⁺ levels only in mice on a low-Mg²⁺ diet without affecting the mRNA expression of colonic or renal Mg²⁺ transporters. Overall, 16S rRNA gene sequencing revealed a lower gut microbial diversity in omeprazole-treated mice. Omeprazole induced a shift in microbial composition, which was associated with a 3- and 2-fold increase in the abundance of Lactobacillus and Bifidobacterium, respectively. To examine the metabolic consequences of these microbial alterations, the colonic composition of organic acids was evaluated. Low dietary Mg²⁺ intake, independent of omeprazole treatment, resulted in a 10-fold increase in formate levels. Together, these results imply that both omeprazole treatment and low dietary Mg²⁺ intake disturb the gut internal milieu and may pose a risk for the malabsorption of Mg²⁺ in the colon.-Gommers, L. M. M., Ederveen, T. H. A., van der Wijst, J., Overmars-Bos, C., Kortman, G. A. M., Boekhorst, J., Bindels, R. J. M., de Baaij, J. H. F., Hoenderop, J. G. J. Low gut microbiota diversity and dietary magnesium intake are associated with the development of PPI-induced hypomagnesemia.

Does the use of proton pump inhibitors increase the risk of hypomagnesemia: An updated systematic review and meta-analysis

BACKGROUND

Proton pump inhibitors (PPIs) are commonly used in the treatment of acid-related diseases; however, the association between the use of PPIs and potential risk of hypomagnesemia is controversial.

METHODS

In the present study, databases including PubMed, EMBASE, MEDLINE, PsycINFO, CINAHL, the Cochrane Library, and 4 Chinese databases were searched since the inception until April 2018. Previous observational studies on the incidence of hypomagnesemia in individuals exposed to PPIs were included.

RESULTS

This systematic review involved 15 studies including 129,347 participants, and the sample size varied from 52 to 95,205. Meta-analysis of 14 studies indicated that the use of PPIs increased the risk of hypomagnesemia [RR, 1.44, 95% CI, 1.13-1.76; I, 85.2%]. Subgroup analysis revealed that the use of PPI was not associated with the incidence of hypomagnesemia in outpatients [RR, 1.49; 95% CI, 0.83-2.14; I, 41.4%] and hospitalized patients [RR, 1.05; 95% CI, 0.81-1.29; I, 62.1%], respectively. The use of PPIs was not related to the risk of hypomagnesemia based on the cut-off values of 1.8 mg/dL [RR, 1.73; 95% CI, 0.87-2.58; I, 65.2%], 1.7 mg/dL [RR, 1.48; 95% CI, 0.90-2.06; I, 87.6%], and 1.6 mg/dL [RR, 0.98; 95% CI, 0.69-1.27; I, 67.9%].

CONCLUSION

The association between the exposure to PPI and the incidence of hypomagnesemia remained unclear. Due to the remarkable heterogeneity in previous studies, a definitive conclusion could not be drawn. Further research should be conducted to investigate the relationship between the use of individual PPI and potential risk of hypomagnesemia, and a dose-response analysis may be required.

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 inhibitor as an independent factor of progression of abdominal aortic calcification in patients on maintenance hemodialysis

BACKGROUNDS

Proton pump inhibitors (PPIs) can be associated with vascular calcification in patients undergoing dialysis through hypomagnesemia. However, only few studies have demonstrated the influence of PPIs on vascular calcification in patients on maintenance hemodialysis (HD). This study aimed to investigate whether the use of PPIs accelerates vascular calcification in patients on HD.

MATERIALS AND METHODS

We retrospectively evaluated 200 HD patients who underwent regular blood tests and computed tomography (CT) between 2016 and 2017. The abdominal aortic calcification index (ACI) was measured using abdominal CT. The difference in the ACI values between 2016 and 2017 was evaluated as ΔACI. Patients were divided into PPI and non-PPI groups, and variables, such as patient background, medication, laboratory data, and ΔACI were compared. Factors independently associated with higher ΔACI progression (≥ third tertile value of ΔACI in this study) were determined using multivariate logistic regression analysis.

RESULTS

The PPI and non-PPI groups had 112 (56%) and 88 (44%) patients, respectively. Median and third tertile value of ΔACIs were 4.2% and 5.8%, respectively. Serum magnesium was significantly lower in the PPI (2.1 mg/dL) than in the non-PPI (2.3 mg/dL) group (P <0.001). Median ΔACI was significantly higher in the PPI (5.0%) than in the non-PPI (3.8%) group (P = 0.009). A total of 77 (39%) patients had a higher ΔACI. Multivariate analysis revealed that PPIs (odds ratio = 2.23; 95% confidence interval = 1.11-4.49), annual mean calcium phosphorus product, ACI in 2016, baseline serum magnesium levels, and HD vintage were independent factors associated with higher ΔACI progression after adjusting for confounders.

CONCLUSION

PPI use may accelerate vascular calcification in patients on HD. Further studies are necessary to elucidate their influence on vascular calcification.

Y. Chiu D, Kalra PA, Green D. Prevalence and outcomes of proton pump inhibitor associated hypomagnesemia in chronic kidney disease

Background

Proton pump inhibitors (PPIs) are one of the most widely prescribed medications across the world. PPIs have been associated with significant electrolyte abnormalities including hypomagnesaemia. We explored the prevalence of PPI associated hypomagnesaemia (PPIH) in different Chronic Kidney Disease (CKD) stages, in different PPI agents, and the impact of PPIH on survival in CKD.

Methods

This was a subgroup analysis of the Salford Kidney Study, a prospective, observational, longitudinal study of non-dialysis CKD patients. Patients with outpatient magnesium samples obtained between 2002 and 2013 were included in the analysis. The prevalence hypomagnesaemia based on mean values over 12 months as well as ‘ever’ hypomagnesaemia were investigated.

Results

1,230 patients were included in this analysis, mean age 64.3± 32.3 years and mean eGFR 29.2±15.8 ml/min/1.73m². Mean serum magnesium in those on PPI was significantly lower than those not on PPI overall (0.85±0.10 mmolL^-1 versus 0.79±0.12 mmolL^-1 respectively, p<0.001). This finding was maintained at all CKD stages. The adjusted odds ratio (OR) for mean hypomagnesaemia in PPI use was 1.12 (95% CI 1.06–1.18) p = <0. ‘Ever hypomagnesaemia’ had an OR of 1.12 (95% CI 1.07–1.16) p = <0.001. The expected rise in serum magnesium with declining eGFR was not observed in those on a PPI but was seen in those not on PPI. There was no difference in serum magnesium between PPI drugs. Thiazide diuretics were also associated with hypomagnesaemia independent of PPI use. Cox regression analysis demonstrated no reduction in survival in patients with PPI associated hypomagnesaemia.

Conclusion

No specific PPI drugs show a favourable profile in regards of risk for hypomagnesaemia in CKD. Avoiding concurrent use of PPI and thiazide may be of value in patients with hypomagnesaemia.

Evaluation of the Predictive Value of the Serum Calcium-Magnesium Ratio for All-Cause and Cardiovascular Mortality in Incident Dialysis Patients

Background/Aim

Cardiovascular disease is the most serious cause of death in patients on hemodialysis. Low serum magnesium (Mg) and high serum calcium (Ca) levels have been associated with poor outcome and cardiovascular mortality in patients on maintenance and initiation dialysis. As a more accurate marker is warranted, we evaluated the efficacy of a novel serum Ca-Mg marker of all-cause and cardiovascular mortality that indicates vessel calcification.

Methods

We recruited 378 consecutive patients with end-stage renal disease who started dialysis between January 2009 and December 2015 at the Japanese Red Cross Ishinomaki Hospital. We collected data of patients' demographic characteristics and comorbidities from their electronic medical records. We retrospectively examined the association of the serum Ca-Mg ratio with all-cause and cardiovascular mortality using the Cox proportional hazard model, and determined the value that predicted cardiovascular death using the receiver operating characteristic (ROC) curve.

Results

Overall, 253 patients with serum Mg and Ca data were analyzed. The 3-year survival rate of this group was 0.70 (95% confidence interval [CI] 0.55-0.80), and the hazard ratio for the risk of death was 3.94 (95% CI 1.37-11.31). The 3-year cardiovascular mortality rate was 0.12 (95% CI 0.05-0.23), which was significantly higher than that of the other groups. The ROC curve of cardiovascular mortality with the Ca-Mg ratio was greater than that of Mg (area under the curve 0.75 vs. 0.69, p = 0.037).

Conclusion

A high Ca-Mg ratio was significantly associated with all-cause and cardiovascular mortality, and it was more accurate than serum Mg.

Ionized and total serum magnesium in hemodialysis: predictors and variability. A longitudinal cross-sectional study

Background

Ionized Magnesium (ion-Mg) represents the active biological fraction of the serum magnesium content. The assessment of total serum Mg (tot-Mg) might not accurately identify patients with hypo-or hyper-magnesaemie. In hemodialysis, serum tot-Mg levels in the upper part of the distribution, have been associated with reduced mortality and fewer vascular calcifications; thus, resulting in the tendency to increase the Mg concentration in the dialysate, traditionally set at 0.5 mmol/L.

Methods

Single-center study in chronic hemodialysis patients, designed in two phases, cross-sectional and longitudinal, aimed to investigate: (1) the sensitivity for pathological values of ion-Mg compared to tot-Mg (2) the predictors of ion-Mg developing ad hoc equations; (3) the inter- and intra-individual variabilities of ion-Mg; and (4) the risk factors for hypermagnesemia. Tot-Mg, ion-Mg, and covariates of 42 hemodialysis sessions, in 42 patients during the cross-sectional phase and of 270 sessions in 27 patients in the longitudinal one were analysed.

Results

Ion-Mg significantly correlates with tot-Mg: β = 0.52; r = 0.88, p < 0.001. Multiple linear regressions in normo- and hypo-albuminemic patients gave the following results: ion-Mg = tot-Mg/2-K⁺/50 + Ca²⁺/5-HCO³⁻/100 and ion-Mg = tot-Mg/2 + albumin/100. Ion-Mg showed a high temporal variability in the longitudinal phase (between months p < 0.001; winter vs. summer, p < 0.027). A high intra-individual variability was also found: coefficient of variation 0.116. Comparing patients with high and low intra-individual variability, we found: age 67 vs. 77 years; p < 0.001; urea 26.3 ± 0.5 vs. 21.2 ± 0.4 mmol/L, p < 0.001; nPCR 0.92 ± 0.1 vs. 0.77 ± 0.1 g/kg day, p < 0.001; PTH 46.3 ± 4 vs. 28.5 ± 3 pmol/L, p < 0.001.

Conclusions

Ion-Mg can be useful in unmasking unrecognized hyper- and hypo-magnesemic and false hyper-magnesemic patients. Ion-Mg is characterized by high intra- and inter-individual variabilities particularly in younger women and those with better nutrition. Patients with greater variability could potentially be at risk if exposed to higher concentrations of magnesium in the dialysate. An interventional study, with controlled increase of magnesium concentrations in the dialysate has been planned.

Magnesium and Risk of Hip Fracture among Patients Undergoing Hemodialysis

Magnesium is an essential mineral for bone metabolism. However, little is known about the relationship between magnesium and the risk of fractures. In this cohort study, we elucidated the association between serum magnesium level and the risk of incident hip fracture among patients undergoing hemodialysis. We identified 113,683 patients undergoing hemodialysis with no history of hip fracture from a nation-wide database of patients undergoing dialysis in Japan. During a 2-year follow-up, a total of 2305 (2%) new hip fractures occurred. The crude incidence rate was significantly higher among patients in the lower quartiles of serum magnesium levels (2.63%, 2.08%, 1.76%, and 1.49% in Q1-Q4, respectively; P<0.001 for trend). The range of serum magnesium levels (in milligrams per deciliter) in each quartile was as follows: Q1, <2.3; Q2, 2.4-2.6; Q3, 2.7-2.8, and Q4, >2.9. After adjustment for demographic and clinical factors, patients in Q1 had a 1.23-fold higher risk for hip fracture than those in Q4 (95% confidence interval, 1.06 to 1.44; P<0.01). Similarly, an inverse probability weighting analysis showed an increased risk of hip fracture among patients in the lower magnesium quartiles. We did not observe significant effect modifications in subgroup analyses. The population-attributable fraction of serum magnesium level for incident hip fractures was 13.7% (95% confidence interval, 3.7% to 22.7%), which was much higher than that of serum calcium, serum phosphate, and parathyroid hormone levels. Thus, mild hypermagnesemia is associated with a lower risk of hip fracture among patients undergoing hemodialysis.

Common single nucleotide polymorphisms in transient receptor potential melastatin type 6 increase the risk for proton pump inhibitor-induced hypomagnesemia: a case-control study

OBJECTIVE

Proton pump inhibitors (PPIs) are effective drugs for the treatment of gastric acid-related disorders. Serious adverse events are rare for PPIs, but recent data suggest that PPIs cause hypomagnesemia. The aim of this study was to estimate the frequency of PPI-induced hypomagnesemia and to define the risk factors for its development.

MATERIALS AND METHODS

A total of 133 chronic users of PPIs were enrolled and patients were distinguished on the basis of their serum Mg concentrations. Common single nucleotide polymorphisms (SNPs) in the candidate gene, transient receptor potential melastatin type 6 (TRPM6), were screened.

RESULTS

Seventeen out of 133 patients had PPI-induced hypomagnesemia. The duration of PPI use was longer in those with hypomagnesemia (7.7 vs. 5.2 years). Two common SNPs in TRPM6 (rs3750425 and rs2274924) increased the risk for PPI-induced hypomagnesemia by 5.8-fold.

CONCLUSION

We found hypomagnesemia in 13% of PPI users. SNPs in TRPM6 drive the risk of developing hypomagnesemia during chronic PPI use.

Proton Pump Inhibitors: More Indigestion than Relief?

Proton pump inhibitors (PPIs) are widely prescribed to treat a number of gastrointestinal (GI) disorders due to excessive acid production. While effective and safe, adverse renal effects have been increasingly described in epidemiological literature. The most well-documented adverse renal outcome is acute interstitial nephritis; however, association with overall acute kidney injury has also been recently reported. Recently, two observational studies have linked PPI use with chronic kidney disease. Finally, hypomagnesemia is another reported complication and is thought to be resulting from GI loss of magnesium. This study will critically review literature on the effect of PPIs on the kidney.

Magnesium Counteracts Vascular Calcification: Passive Interference or Active Modulation?

Over the last decade, an increasing number of studies report a close relationship between serum magnesium concentration and cardiovascular disease risk in the general population. In end-stage renal disease, an association was found between serum magnesium and survival. Hypomagnesemia was identified as a strong predictor for cardiovascular disease in these patients. A substantial body of in vitro and in vivo studies has identified a protective role for magnesium in vascular calcification. However, the precise mechanisms and its contribution to cardiovascular protection remain unclear. There are currently 2 leading hypotheses: first, magnesium may bind phosphate and delay calcium phosphate crystal growth in the circulation, thereby passively interfering with calcium phosphate deposition in the vessel wall. Second, magnesium may regulate vascular smooth muscle cell transdifferentiation toward an osteogenic phenotype by active cellular modulation of factors associated with calcification. Here, the data supporting these major hypotheses are reviewed. The literature supports both a passive inorganic phosphate-buffering role reducing hydroxyapatite formation and an active cell-mediated role, directly targeting vascular smooth muscle transdifferentiation. However, current evidence relies on basic experimental designs that are often insufficient to delineate the underlying mechanisms. The field requires more advanced experimental design, including determination of intracellular magnesium concentrations and the identification of the molecular players that regulate magnesium concentrations in vascular smooth muscle cells.

Dialysate Composition for Hemodialysis: Changes and Changing Risk

Dialysate composition is a critical aspect of the hemodialysis prescription. Despite this, trial data are almost entirely lacking to help guide the optimal dialysate composition. Often, the concentrations of key components are chosen intuitively, and dialysate composition may be determined by default based on dialysate manufacturer specifications or hemodialysis facility practices. In this review, we examine the current epidemiological evidence guiding selection of dialysate bicarbonate, calcium, magnesium, and potassium, and identify unresolved issues for which pragmatic clinical trials are needed.

Effects of Magnesium on the Phosphate Toxicity in Chronic Kidney Disease: Time for Intervention Studies

Magnesium, an essential mineral for human health, plays a pivotal role in the cardiovascular system. Epidemiological studies in the general population have found an association between lower dietary magnesium intake and an elevated risk of cardiovascular events. In addition, magnesium supplementation was shown to improve blood pressure control, insulin sensitivity, and endothelial function. The relationship between magnesium and cardiovascular prognosis among patients with chronic kidney disease (CKD) has been increasingly investigated as it is becoming evident that magnesium can inhibit vascular calcification, a prominent risk of cardiovascular events, which commonly occurs in CKD patients. Cohort studies in patients receiving dialysis have shown a lower serum magnesium level as a significant risk for cardiovascular mortality. Interestingly, the cardiovascular mortality risk associated with hyperphosphatemia is alleviated among those with high serum magnesium levels, consistent with in vitro evidence that magnesium inhibits high-phosphate induced calcification of vascular smooth muscle cells. Furthermore, a harmful effect of high phosphate on the progression of CKD is also attenuated among those with high serum magnesium levels. The potential usefulness of magnesium as a remedy for phosphate toxicity should be further explored by future intervention studies.