Low Magnesium Exacerbates Osteoporosis in Chronic Kidney Disease Patients with Diabetes

To evaluate the relationship between serum magnesium and parathyroid hormone levels in peritoneal dialysis and hemodialysis patients

OBJECTS

This study aimed to determine the relationship between magnesium and PTH levels in peritoneal dialysis (PD) and hemodialysis (HD) patients.

METHODS

This cross-sectional study was performed on HD and PD patients in Kerman, Iran. After recording demographic and clinical data, the pre-dialysis levels of hemoglobin, 25-hydroxy vitamin D, ferritin, creatinine, calcium, phosphorus, albumin, PTH, and magnesium were measured for all patients. The P value of less than 0.05 was considered statistically significant.

RESULTS

Magnesium levels in PD patients were significantly higher than in HD patients (P < 0.001). The median PTH level in PD patients was significantly lower than in HD patients (P = 0.046). The correlation between PTH and serum magnesium levels was not significant in PD or HD patients. In the regression model, dialysis modality (PD or HD) was the only significant variable in determining serum magnesium levels (P = 0.005).

CONCLUSION

Magnesium is a neglected ion in peritoneal dialysis and hemodialysis patients. In dialysis centers that use a dialysate with standard magnesium concentration (0.5 mmol/L in HD and 0.75 mmol/L in PD), special attention is necessary to hypomagnesia and its complications because magnesium levels in PD patients were significantly higher than in HD patients. As the correlation between magnesium and PTH levels in both PD and HD patients were not significant, the association of high magnesium levels with low PTH in PD patients should be considered in terms of increasing the potential for adynamic bone disease. It seems that ordering serum magnesium in the routine tests of dialysis patients is necessary.

Proton pump inhibitors and osteoporosis risk: exploring the role of TRPM7 channel

BACKGROUND

Long-term use of proton pump inhibitors (PPIs) has been linked to an increased risk of osteoporosis, with various indirect mechanisms so far identified. Although no direct underlying mechanism for effect on bone cells have been investigated with the use of PPIs. Melastatin-like transient receptor potential 7 (TRPM7)channel has been engaged in the proliferation of bone cells. TRPM7 channel is regulated by extracellular Mg²⁺ and Ca²⁺ level, that further encourages to analyse if any imbalance with pantoprazole usage could alter bone remodelling process mediated by TRPM7.

OBJECTIVES

The present study was conducted to investigate the effect of pantoprazole on the calcium and magnesium level, the cations involved in the bone remodelling process, as well as role of the TRPM7 channel in the proliferation of bone cells.

METHODS

A cytotoxicity study was carried out to study the effect of pantoprazole on the bone cell using MC3T3-E1 cell line, together with the expression of TRPM7 was determined post-pantoprazole treatment. An in vivo study in rats was carried out for estimation of Ca²⁺, Mg²⁺ and Ca²⁺/Mg²⁺ ratio as well as bone strength was measured over a duration of 4 weeks and 8 weeks with the treatment of pantoprazole. A pilot-scale clinical study was carried out in patients with a fracture to support the evidence of preliminary findings from in-vitro and in vivo studies.

RESULTS

MC3T3-E1 cell line treated with pantoprazole showed decreased cell viability in a dose-dependent manner and reduced expression of TRPM7 channel, evidencing interaction of TRPM7 and pantoprazole in the bone remodelling process. A pilot study conducted on 12 patients having major fractures showed changes in serum Mg²⁺ and Ca²⁺ levels over a period of 1 month as well as the animal study also showed ionic imbalance over 8-week treatment with pantoprazole. Bone density measured for the patient at the end of the 1-month treatment was found to be in the osteopenic category, together with the animal study which showed a decrease in femur bone strength for the animal treated with pantoprazole over a period of 8 weeks.

CONCLUSION

The study findings proved a negative impact of pantoprazole use on Ca²⁺ and Mg²⁺ levels, which can impact TRPM7-mediated bone remodelling which serves to be a possible mechanism for osteoporosis upon pantoprazole use.

An update on magnesium and bone health

In 2009 EFSA Panel concludes that a cause and effect relationship has been established between the dietary intake of magnesium (Mg) and maintenance of normal bone. After 2009, numerous studies have been published, but no reviews have made an update on this topic. So, the aim of this narrative review was to consider the state of the art since 2009 on relationship between Mg blood levels, Mg dietary intake and Mg dietary supplementation (alone or with other micronutrients; this last topic has been considered since 1990, because it is not included in the EFSA claims) and bone health in humans. This review included 28 eligible studies: nine studies concern Mg blood, 12 studies concern Mg intake and seven studies concern Mg supplementation, alone or in combination with other nutrients. From the various studies carried out on the serum concentration of Mg and its relationship with the bone, it has been shown that lower values are related to the presence of osteoporosis, and that about 30–40% of the subjects analyzed (mainly menopausal women) have hypomagnesaemia. Various dietetic investigations have shown that many people (about 20%) constantly consume lower quantities of Mg than recommended; moreover, in this category, a lower bone mineral density and a higher fracturing risk have been found. Considering the intervention studies published to date on supplementation with Mg, most have used this mineral in the form of citrate, carbonate or oxide, with a dosage varying between 250 and 1800 mg. In all studies there was a benefit both in terms of bone mineral density and fracture risk.

The Role of Bone Biopsy in the Management of CKD-MBD

A bone biopsy is still considered the gold standard for diagnosis of renal osteodystrophy. It allows to measure both static and dynamic parameters of bone remodeling and is the only method able to evaluate mineralization and allows analysis of both cortical and trabecular bone. Although bone volume can be measured indirectly by dual-energy X-ray absorptiometry, mineralization defects, bone metal deposits, cellular number/activity, and even turnover abnormalities are difficult to determine by techniques other than qualitative bone histomorphometry. In this review, we evaluate the role of bone biopsy in the clinical practice.

Chronic kidney disease-related osteoporosis is associated with incident frailty among patients with diabetic kidney disease: a propensity score-matched cohort study

Chronic kidney disease (CKD)-related osteoporosis is a major complication in patients with CKD, conferring a higher risk of adverse outcomes. We found that among those with diabetic kidney disease, this complication increased the risk of incident frailty, an important mediator of adverse outcomes.

INTRODUCTION

Renal osteodystrophy and chronic kidney disease (CKD)-related osteoporosis increases complications for patients with diabetic kidney disease (DKD). Since musculoskeletal degeneration is central to frailty development, we investigated the relationship between baseline osteoporosis and the subsequent frailty risk in patients with DKD.

METHODS

From the Longitudinal Cohort of Diabetes Patients in Taiwan (n = 840,000), we identified 12,027 patients having DKD with osteoporosis and 24,054 propensity score-matched controls having DKD but without osteoporosis. The primary endpoint was incident frailty on the basis of a modified FRAIL scale. Patients were prospectively followed-up until the development of endpoints or the end of this study. The Kaplan-Meier technique and Cox proportional hazard regression were used to analyze the association between osteoporosis at baseline and incident frailty in these patients.

RESULTS

The mean age of the DKD patients was 67.2 years, with 55.4% female and a 12.6% prevalence of osteoporosis at baseline. After 3.5 ± 2.2 years of follow up, the incidence rate of frailty in patients having DKD with osteoporosis was higher than that in DKD patients without (6.6 vs. 5.7 per 1000 patient-year, p = 0.04). A Cox proportional hazard regression showed that after accounting for age, gender, obesity, comorbidities, and medications, patients having DKD with osteoporosis had a significantly higher risk of developing frailty (hazard ratio, 1.19; 95% confidence interval, 1.02-1.38) than those without osteoporosis.

CONCLUSIONS

CKD-related osteoporosis is associated with a higher risk of incident frailty in patients with DKD.

Magnesium and Human Health: Perspectives and Research Directions

Magnesium is the fourth most abundant cation in the body. It has several functions in the human body including its role as a cofactor for more than 300 enzymatic reactions. Several studies have shown that hypomagnesemia is a common electrolyte derangement in clinical setting especially in patients admitted to intensive care unit where it has been found to be associated with increase mortality and hospital stay. Hypomagnesemia can be caused by a wide range of inherited and acquired diseases. It can also be a side effect of several medications. Many studies have reported that reduced levels of magnesium are associated with a wide range of chronic diseases. Magnesium can play important therapeutic and preventive role in several conditions such as diabetes, osteoporosis, bronchial asthma, preeclampsia, migraine, and cardiovascular diseases. This review is aimed at comprehensively collating the current available published evidence and clinical correlates of magnesium disorders.

Serum Magnesium and Related Factors in Long-Term Renal Transplant Recipients: An Observational Study

BACKGROUND

Low serum magnesium (MgS) is a known risk factor for cardiovascular and mineral bone disease. In renal transplant recipients (RTRs), low MgS levels have been related to higher glomerular filtration rates (GFR) and with calcineurin inhibitors, particularly tacrolimus. We aimed to evaluate MgS in renal transplant recipients with over 1 year of follow-up to establish related risk factors and the impact of the use of cyclosporine versus tacrolimus.

METHODS

Cross-sectional study of 94 RTRs with more than 12 months of follow-up. Hypomagnesemia was defined as serum magnesium level <1.5 mg/dL.

RESULTS

Hypomagnesemia was found in 5.3% of patients. MgS showed a negative correlation with creatinine clearance. A positive correlation between MgS with urinary magnesium and phosphorus was found. Cyclosporine versus tacrolimus analysis did not show a significant difference regarding MgS when considering all the population and the subgroup of patients with GFR >45 mL/min/1.73 m². On the subgroup with GFR <45 mL/min/1.73 m², those on tacrolimus had lower MgS than those on cyclosporine, but those same patients presented with significantly different GFR, higher in the tacrolimus subgroup.

CONCLUSIONS

Hypomagnesemia has a low prevalence in RTRs with more than 1 year of follow-up. MgS levels evidenced a strong correlation with GFR. A significant difference on MgS levels between patients on tacrolimus and cyclosporine was found only when considering GFR <45 mL/min/1.73 m², in which patients on tacrolimus had significantly higher GFR than patients on cyclosporine, which may explain these results.