Association between hypomagnesemia and severity of primary hyperparathyroidism: a retrospective study.

BACKGROUND: The occurrence of hypomagnesemia in patients with primary hyperparathyroidism (PHPT) has been noted previously; however, the association of hypomagnesemia and severity of primary hyperparathyroidism remains unknown. The present study aimed to evaluate the association of hypomagnesemia with biochemical and clinical manifestations in patients with PHPT. METHODS: This was a retrospective study conducted at a tertiary hospital. We obtained data from 307 patients with PHPT from January 2010 through August 2020. Data on demographics, history, laboratory findings, bone densitometry findings, and clinical presentation and complications were collected and were compared in normal magnesium group vs hypomagnesemia group. RESULTS: Among the 307 patients with PHPT included in our study, 77 patients (33/102 [32.4%] males and 44/205 [21.5%] females) had hypomagnesemia. Mean hemoglobin levels in the hypomagnesemia group were significantly lower than those in the normal magnesium group in both males and females. In contrast, patients with hypomagnesemia had a higher mean serum calcium and parathyroid hormone than individuals with normal magnesium. The typical symptoms of PHPT, such as nephrolithiasis, bone pain/fractures, polyuria, or polydipsia, were more common in the hypomagnesemia group. In addition, patients with hypomagnesemia had a higher prevalence of osteoporosis, anemia, and hypercalcemic crisis. Even after adjusting for potential confounders, including age, sex, body mass index, estimated glomerular filtration rate, and parathyroid hormone levels, these associations remained essentially unchanged. CONCLUSION: Biochemical and clinical evidence indicates that patients with PHPT with hypomagnesemia have more severe hyperparathyroidism than those without hypomagnesemia. In addition, PHPT patients with hypomagnesemia had a higher prevalence of osteoporosis, anemia, and hypercalcemic crisis.

Renal effects of uric acid: hyperuricemia and hypouricemia.

The prevalence of chronic kidney disease (CKD) is increasing worldwide. Although hyperuricemia has been associated with CKD in many studies, it remains controversial whether this is the cause or the result of decreased renal function. Recent observational studies of healthy populations and patients with CKD have reported that uric acid (UA) has an independent role in the development or progression of CKD. Experimental studies have shown several potential mechanisms by which hyperuricemia may cause or promote CKD. However, other reports have indicated an association between hypouricemia and CKD. This opposing effect is hypothesized to occur because UA is a major antioxidant in human plasma and is associated with oxidative stress. In this article, we discuss the potential association between UA imbalance and CKD and how they can be treated.

Predictive and prognostic value of magnesium serum level in FOLFIRI plus cetuximab or bevacizumab treated patients with stage IV colorectal cancer: results from the FIRE-3 (AIO KRK-0306) study.

Magnesium wasting is a frequent side effect of epidermal growth factor receptor (EGFR)-antibody treatment as magnesium-absorption mechanisms are dependent on EGFR signaling. EGFR-inhibition results in decreased renal reabsorption. There is evidence that hypomagnesemia during cetuximab treatment correlates with response. The prognostic role of hypomagnesemia during bevacizumab treatment has not been studied yet. Here, we evaluate the prognostic value of hypomagnesemia in patients with metastatic colorectal cancer treated with FOLFIRI plus cetuximab or bevacizumab as first-line therapy. A total of 391 of 752 patients of the firstline irinotecan study population had magnesium levels measured at baseline and for the first three cycles (6 weeks) of treatment. Of those, 240 had Rat Sarkoma wildtype tumors. Overall hypomagnesemia was more common in the cetuximab compared to the bevacizumab arm (80 vs. 43%, P < 0.005). During therapy, magnesium showed a time-dependent decrease to 80% of baseline in the cetuximab and to 89% in the bevacizumab arm. Whereas magnesium continued to decrease over time in the cetuximab-treated patients, it remained stable in the bevacizumab-treated. Overall response rate (ORR) was associated with higher magnesium at week 6 (20.9 vs. 79.1%, P = 0.041). Bevacizumab-treated patients with magnesium levels below the median value at week 6 had a significantly longer progression-free survival (PFS; 11.7 vs. 9.9 months, P = 0.034; hazard ratio 0.73) and a trend towards longer overall survival (OS) (29.6 vs. 23.2 months, P = 0.089; hazard ratio 0.77). Hypomagnesemia at predefined time points and magnesium nadir had no significant effect on ORR, OS and PFS in the cetuximab arm. Our data show different magnesium kinetics in patients with metastatic colorectal cancer treated with cetuximab or bevacizumab. For patients treated with cetuximab, hypomagnesemia did not have an impact on response and survival. Hypomagnesemia might have a prognostic value in bevacizumab treatment.

U-Shaped Association of Serum Uric Acid With All-Cause and Cause-Specific Mortality in US Adults: A Cohort Study.

BACKGROUND: In addition to the controversy regarding the association of hyperuricemia with mortality, uncertainty also remains regarding the association between low serum uric acid (SUA) and mortality. We aimed to assess the relationship between SUA and all-cause and cause-specific mortality. METHODS: This cohort study included 9118 US adults from the National Health and Nutrition Examination Survey (1999-2002). Multivariable Cox proportional hazards models were used to evaluate the relationship between SUA and mortality. Our analysis included the use of a generalized additive model and smooth curve fitting (penalized spline method), and 2-piecewise Cox proportional hazards models, to address the nonlinearity between SUA and mortality. RESULTS: During a median follow-up of 5.83 years, 448 all-cause deaths occurred, with 100 cardiovascular disease (CVD) deaths, 118 cancer deaths, and 37 respiratory disease deaths. Compared with the reference group, there was an increased risk of all-cause, CVD, cancer, and respiratory disease mortality for participants in the first and third tertiles of SUA. We further found a nonlinear and U-shaped association between SUA and mortality. The inflection point for the curve was found at a SUA level of 5.7 mg/dL. The hazard ratios (95% confidence intervals) for all-cause mortality were 0.80 (0.65-0.97) and 1.24 (1.10-1.40) to the left and right of the inflection point, respectively. This U-shaped association was observed in both sexes; the inflection point for SUA was 6 mg/dL in males and 4 mg/dL in females. CONCLUSION: Both low and high SUA levels were associated with increased all-cause and cause-specific mortality, supporting a U-shaped association between SUA and mortality.

Hypomagnesemia and Survival in Patients with Ovarian Cancer Who Received Chemotherapy with Carboplatin.

BACKGROUND: Hypomagnesemia is a known side effect of several antineoplastic agents, but its impact on outcomes of patients with cancer is not well understood. We examined whether magnesium abnormalities affect survival in patients with ovarian cancer who receive chemotherapy containing carboplatin. MATERIALS AND METHODS: We included patients with advanced ovarian cancer who had undergone surgery and chemotherapy between January 1, 2004, and December 31, 2014, at our institution. Inclusion criteria were age 18 years or older, pathology of high-grade serous carcinoma, first treatment (surgery or chemotherapy) within 60 days of diagnosis, and chemotherapy containing carboplatin. The final cohort consisted of 229 patients. Vital signs and laboratory tests were recorded at baseline and during the treatment course. The associations between magnesium abnormalities (and other clinical characteristics) and survival were analyzed. RESULTS: The median patient age was 64 years. Higher baseline heart rate (beats per minute; hazard ratio [HR] = 1.02, p = .002) and greater frequency of hypomagnesemia during the treatment course (HR = 1.05, p = .002) were significantly associated with shorter survival independent of completeness of tumor reduction (HR = 1.60, p = .02), and International Federation of Gynecology and Obstetrics stage (HR = 1.63, p = .01). CONCLUSION: Baseline heart rate and the frequency of hypomagnesemia episodes during treatment are prognostic of survival for patients with advanced ovarian cancer receiving carboplatin-containing chemotherapy and tumor reductive surgery. Future research is needed for strategies to detect and prevent hypomagnesemia in this patient population. IMPLICATIONS FOR PRACTICE: Despite standard laboratory tests and intravenous magnesium replacement prior to each cycle of chemotherapy, hypomagnesemia remains a common side effect of platinum-based chemotherapy. This study revealed that frequent occurrence of hypomagnesemia during the course of treatment including carboplatin-containing chemotherapy and tumor reductive surgery was strongly predictive of shorter survival in patients with advanced ovarian cancer. Strategies to effectively mitigate hypomagnesemia, such as more frequent detection, dietary recommendations, and timely replacement, should be considered in the overall cancer treatment plan for these patients.

Distribution and Characteristics of Hypouricemia within the Japanese General Population: A Cross-Sectional Study.

Background and objectives: There is insufficient epidemiological knowledge of hypouricemia. In this study, we aimed to describe the distribution and characteristics of Japanese subjects with hypouricemia. Materials and Methods: Data from subjects who underwent routine health checkups from January 2001 to December 2015 were analyzed in this cross-sectional study. A total of 246,923 individuals, which included 111,117 men and 135,806 women, met the study criteria. The participants were divided into quartiles according to their serum uric acid (SUA) levels. We subdivided the subjects with hypouricemia, which was defined as SUA level ≤ 2.0 mg/dL, into two groups and compared their characteristics, including their cardiovascular risks. Results: The hypouricemia rates were 0.46% overall, 0.21% for the men and 0.66% for the women (P < 0.001). The number of the subjects with hypouricemia showed two distributions at SUA levels of 0.4⁻1.1 mg/dL (lower hypouricemia group), which included a peak at 0.7⁻0.8 mg/dL, and at SUA levels of 1.4⁻2.0 mg/dL (higher hypouricemia group). The men in the higher hypouricemia group had lower body mass indexes (BMI) and triglyceride (TG) levels and had higher fasting blood glucose levels than those in the lower hypouricemia group. The women in the higher hypouricemia group were younger; had lower BMI, total protein, TG, total cholesterol and low-density lipoprotein cholesterol levels; and had higher estimated glomerular filtration rates levels compared to those in the lower hypouricemia group. Conclusions: The characteristics of the individuals in the lower and higher hypouricemia groups differed significantly, indicating different pathophysiologies within each group.

Hypomagnesaemia is absent in children with autosomal dominant polycystic kidney disease.

BACKGROUND: Hypomagnesaemia is present in 40-50% of children with autosomal dominant renal cysts and diabetes syndrome (RCAD). On the contrary, the prevalence of hypomagnesaemia in children with autosomal dominant polycystic kidney disease (ADPKD) has never been examined. We aimed to investigate whether hypomagnesaemia is present in children with polycystic kidney diseases. METHODS: Children with cystic kidney diseases were investigated in a cross-sectional study. Serum concentrations of magnesium (S-Mg) and fractional excretion of magnesium (FE-Mg) were tested. Fifty-four children with ADPKD ( n = 26), autosomal recessive polycystic kidney disease (ARPKD) ( n = 16) and RCAD ( n = 12) with median age of 11.2 (0.6-18.6) years were investigated. RESULTS: Hypomagnesaemia (S-Mg < 0.7 mmol/L) was detected in none of the children with ADPKD/ARPKD and in eight children (67%) with RCAD. Median S-Mg in children with ADPKD/ARPKD was significantly higher than in children with RCAD (0.89 vs. 0.65 mmol/L, P < 0.01). The FE-Mg was increased in 23% of patients with ADPKD/ARPKD (all had chronic kidney disease stages 2-4) and in 63% of patients with RCAD, where it significantly correlated with estimated glomerular filtration rate (r = -0.87, P < 0.01). CONCLUSIONS: Hypomagnesaemia is absent in children with ADPKD or ARPKD and could serve as a marker for differential diagnostics between ADPKD, ARPKD and RCAD in children with cystic kidney diseases of unknown origin where molecular genetic testing is lacking. However, while hypomagnesaemia, in the absence of diuretics, appears to rule out ADPKD and ARPKD, normomagnesaemia does not rule out RCAD at least in those aged <3 years.

Short-Term Effect of High-Dose Pantoprazol on Serum and Urinary Magnesium Levels.

BACKGROUND: Proton pump inhibitor (PPI) induced hypomagnesemia is a completely unexplained issue and cases are still being reported. Long-term use is the main factor, but there are a few articles stating that it may also emerge with short-term use. We aimed to evaluate the changes of serum and urine magnesium levels during shortterm high dose pantoprazol treatment. METHODS: The serum and 24-hour urine magnesium levels of 58 patients were evaluated during the course of 2 days. Of 58 patients, 25 were allowed oral intake on the 3rd day of hospitalization and thus, 24-hour urine for 3 days was collected from 33 patients. RESULTS: There were no significant differences in the mean levels of serum magnesium and the median levels of urine magnesium. When the magnesium levels were evaluated by age over and under 60 years, the baseline serum magnesium level was significantly higher than the 1st level in patients aged ≥ 60 years (p = 0.029). The 3rd day serum magnesium level was significantly higher than the baseline and 1st day levels in those aged < 60 years (p = 0.049). CONCLUSIONS: We showed that plasma levels and urinary excretion of magnesium did not change significantly during high-dose pantoprazol treatment. It can be hypothesized that magnesium levels are not affected by PPIs in short-term usage. Age and other contributing factors may have more impact on PPI induced hypomagnesemia. Patients aged over 60 years might be handled carefully under proton pump inhibitors treatment.

Hereditary xanthinuria is not so rare disorder of purine metabolism.

Hereditary xanthinuria (type I) is caused by an inherited deficiency of the xanthine oxidorectase (XDH/XO), and is characterized by very low concentration of uric acid in blood and urine and high concentration of urinary xanthine, leading to urolithiasis. Type II results from a combined deficiency of XDH/XO and aldehyde oxidase. Patients present with hematuria, renal colic, urolithiasis or even acute renal failure. Clinical symptoms are the same for both types. In a third type, clinically distinct, sulfite oxidase activity is missing as well as XDH/XO and aldehyde oxidase. The prevalence is not known, but about 150 cases have been described so far. Hypouricemia is sometimes overlooked, that´s why we have set up the diagnostic flowchart. This consists of a) evaluation of uric acid concentrations in serum and urine with exclusion of primary renal hypouricemia, b) estimation of urinary xanthine, c) allopurinol loading test, which enables to distinguish type I and II; and finally assay of xanthine oxidoreductase activity in plasma with molecular genetic analysis. Following this diagnostic procedure we were able to find first patients with hereditary xanthinuria in our Czech population. We have detected nine cases, which is one of the largest group worldwide. Four patients were asymptomatic. All had profound hypouricemia, which was the first sign and led to referral to our department. Urinary concentrations of xanthine were in the range of 170-598 mmol/mol creatinine (normal < 30 mmol/mol creatinine). Hereditary xanthinuria is still unrecognized disorder and subjects with unexplained hypouricemia need detailed purine metabolic investigation.

Hypomagnesemia During Teriparatide Treatment in Osteoporosis: Incidence and Determinants.

In our clinical experience, we have encountered patients who developed hypomagnesemia after the introduction of teriparatide. Some trials have reported hypomagnesemia as an adverse event during teriparatide treatment, but this issue had never been studied specifically. Our objective was twofold: 1) determine the incidence of hypomagnesemia (serum magnesium <0.7 mmol/L) associated with teriparatide in a retrospective cohort and 2) identify the predisposing factors to hypomagnesemia in this cohort. We reviewed the files of 53 patients treated for severe osteoporosis with teriparatide for 6 to 24 months between May 2008 and January 2016. Serum magnesium levels were measured at 0, 3, 6, 12, 18, and 24 months. In the full cohort, we observed an average decrease of serum magnesium of 0.075 mmol/L, 0.069 mmol/L, 0.085 mmol/L, 0.086 mmol/L (p < 0.001) at 3, 6, 12 months, and at the end of the treatment, respectively. The cumulative incidence of hypomagnesemia during treatment with teriparatide was 35.9% (19 patients). Patients' older age (71.1 versus 65.1 years; p = 0.05) and lower baseline level of magnesium before teriparatide treatment (0.81 mmol/L versus 0.85 mmol/L; p = 0.03) were significant risk factors for teriparatide-induced hypomagnesemia. The average decrease of serum magnesium was greater in the patients who developed hypomagnesemia compared with normomagnesemic patients at 3 months (0.110 mmol/L versus 0.054 mmol/L; p = 0.02), 6 months (0.139 mmol/L versus 0.036 mmol/L; p < 0.001), and 12 months (0.156 mmol/L versus 0.048 mmol/L; p < 0.001). Serum calcium, creatinine, and parathyroid hormone remained normal throughout the treatment period. We observed a statistically significant decrease in the serum magnesium levels in patients treated with teriparatide for severe osteoporosis. Older age and lower baseline magnesium were significant determinants of hypomagnesemia. Closer monitoring of serum magnesium level should be considered in these patients. © 2018 American Society for Bone and Mineral Research.

Uric acid and cognitive decline: a double-edge sword?

PURPOSE OF REVIEW: This narrative review aims to highlight recent findings on the relation between uric acid level and cognitive decline or dementia. RECENT FINDINGS: The antioxidant properties of uric acid, which have supported the hypothesis that uric acid may be neuroprotective, have been questioned by preclinical data. Studies investigating the relation between serum uric acid (SUA) level and Alzheimer disease are mostly cross-sectional, and results are often inconclusive. Similarly, data for an association between uric acid level and cognitive performance are inconsistent. There is some evidence that low SUA level might be associated with Parkinson disease, but studies are limited by methodological heterogeneity and risk of bias. Patients with gout may have decreased risk for Alzheimer disease, but the impact of treatment is unclear. Recent data suggest an increased risk of vascular dementia with high SUA level via increased cerebrovascular burden in older patients. The relation between SUA level and neurologic disorders may be U-shaped. SUMMARY: We lack strong evidence for an association between low SUA level and cognitive decline over time. Conversely, high SUA level might increase the cerebrovascular burden and the risk of vascular dementia; physicians should continue to treat hyperuricemia when appropriate.

Antibody-mediated inhibition of EGFR reduces phosphate excretion and induces hyperphosphatemia and mild hypomagnesemia in mice.

Monoclonal antibody therapies targeting the EGF receptor (EGFR) frequently result in hypomagnesemia in human patients. In contrast, EGFR tyrosine kinase inhibitors do not affect Mg2+ balance in patients and only have a mild effect on Mg2+ homeostasis in rodents at elevated doses. EGF has also been shown to affect phosphate (Pi) transport in rat and rabbit proximal convoluted tubules (PCT), but evidence from studies targeting EGFR and looking at Pi excretion in whole animals is still missing. Thus, the role of EGF in regulating reabsorption of Mg2+ and/or Pi in the kidney remains controversial. Here, we inject mice with the anti-EGFR monoclonal antibody ME-1 for 2 weeks and observe a significant increase in serum Pi and mild hypomagnesemia, but no changes in Pi or Mg2+ excretion. In contrast, a single injection of ME-1 resulted in hyperphosphatemia and a significant reduction in Pi excretion 2 days after treatment, while no changes in serum Mg2+ or Mg2+ excretion were observed. Dietary Mg2+ deprivation is known to trigger a rapid Mg2+ conservation response in addition to hyperphosphatemia and hyperphosphaturia. Interestingly, one dose of ME-1 did not significantly modify the response of mice to 2 days of Mg2+ deprivation. These data show that EGFR plays a significant role in regulating Pi reabsorption in the kidney PCT, but suggest only a minor role in long-term regulation of Mg2+ transport in the distal convoluted tubule.

Genetic causes of hypomagnesemia, a clinical overview.

Magnesium is essential to the proper functioning of numerous cellular processes. Magnesium ion (Mg2+) deficits, as reflected in hypomagnesemia, can cause neuromuscular irritability, seizures and cardiac arrhythmias. With normal Mg2+ intake, homeostasis is maintained primarily through the regulated reabsorption of Mg2+ by the thick ascending limb of Henle's loop and distal convoluted tubule of the kidney. Inadequate reabsorption results in renal Mg2+ wasting, as evidenced by an inappropriately high fractional Mg2+ excretion. Familial renal Mg2+ wasting is suggestive of a genetic cause, and subsequent studies in these hypomagnesemic families have revealed over a dozen genes directly or indirectly involved in Mg2+ transport. Those can be classified into four groups: hypercalciuric hypomagnesemias (encompassing mutations in CLDN16, CLDN19, CASR, CLCNKB), Gitelman-like hypomagnesemias (CLCNKB, SLC12A3, BSND, KCNJ10, FYXD2, HNF1B, PCBD1), mitochondrial hypomagnesemias (SARS2, MT-TI, Kearns-Sayre syndrome) and other hypomagnesemias (TRPM6, CNMM2, EGF, EGFR, KCNA1, FAM111A). Although identification of these genes has not yet changed treatment, which remains Mg2+ supplementation, it has contributed enormously to our understanding of Mg2+ transport and renal function. In this review, we discuss general mechanisms and symptoms of genetic causes of hypomagnesemia as well as the specific molecular mechanisms and clinical phenotypes associated with each syndrome.

Posterior reversible encephalopathy syndrome (PRES) and hypomagnesemia: A frequent association?

Posterior reversible encephalopathy syndrome (PRES) is a serious neurological condition encountered in various medical fields. Pathophysiological factor(s) common to PRES cases of apparently unrelated etiologies are yet to be found. Based on the hypothesis that hypomagnesemia might participate in the cascade leading to PRES, our study sought to verify whether hypomagnesemia is frequently associated with PRES regardless of etiology. From a retrospective study of a cohort of 57 patients presenting with PRES of different etiologies, presented here are the findings of 19 patients with available serum magnesium levels (SMLs) during PRES. In the acute phase of PRES, hypomagnesemia was present in all 19 patients in spite of differences in etiology (including immunosuppressive drugs, hypertensive encephalopathy, eclampsia, systemic lupus erythematosus, iatrogenic etiology and unknown). SMLs were within normal ranges prior to PRES and below normal ranges during the first 48h of PRES, with a significant decrease in SMLs during the acute phase. In this retrospective study, constant hypomagnesemia was observed during the acute phase of PRES regardless of its etiology. These results now require larger studies to assess the particular importance of acute hypomagnesemia in PRES and especially the possible need to treat PRES with magnesium sulfate.

Identification of SLC41A3 as a novel player in magnesium homeostasis.

Regulation of the body Mg(2+) balance takes place in the distal convoluted tubule (DCT), where transcellular reabsorption determines the final urinary Mg(2+) excretion. The basolateral Mg(2+) extrusion mechanism in the DCT is still unknown, but recent findings suggest that SLC41 proteins contribute to Mg(2+) extrusion. The aim of this study was, therefore, to characterize the functional role of SLC41A3 in Mg(2+) homeostasis using the Slc41a3 knockout (Slc41a3(-/-)) mouse. By quantitative PCR analysis it was shown that Slc41a3 is the only SLC41 isoform with enriched expression in the DCT. Interestingly, serum and urine electrolyte determinations demonstrated that Slc41a3(-/-) mice suffer from hypomagnesemia. The intestinal Mg(2+) absorption capacity was measured using the stable (25)Mg(2+) isotope in mice fed a low Mg(2+) diet. (25)Mg(2+) uptake was similar in wildtype (Slc41a3(+/+)) and Slc41a3(-/-) mice, although Slc41a3(-/-) animals exhibited increased intestinal mRNA expression of Mg(2+) transporters Trpm6 and Slc41a1. Remarkably, some of the Slc41a3(-/-) mice developed severe unilateral hydronephrosis. In conclusion, SLC41A3 was established as a new factor for Mg(2+) handling.

Hypomagnesemia Is Associated with Increased Mortality among Peritoneal Dialysis Patients.

OBJECTIVE: Hypomagnesemia has been associated with an increase in mortality among the general population as well as patients with chronic kidney disease or those on hemodialysis. However, this association has not been thoroughly studied in patients undergoing peritoneal dialysis. The aim of this study was to evaluate the association between serum magnesium concentrations and all-cause and cardiovascular mortalities in peritoneal dialysis patients. METHODS: This single-center retrospective study included 253 incident peritoneal dialysis patients enrolled between July 1, 2005 and December 31, 2014 and followed to June 30, 2015. Patient's demographic characteristics as well as clinical and laboratory measurements were collected. RESULTS: Of 253 patients evaluated, 36 patients (14.2%) suffered from hypomagnesemia. During a median follow-up of 29 months (range: 4-120 months), 60 patients (23.7%) died, and 35 (58.3%) of these deaths were attributed to cardiovascular causes. Low serum magnesium was positively associated with peritoneal dialysis duration (r = 0.303, p < 0.001) as well as serum concentrations of albumin (r = 0.220, p < 0.001), triglycerides (r = 0.160, p = 0.011), potassium (r = 0.156, p = 0.013), calcium(r = 0.299, p < 0.001)and phosphate (r = 0.191, p = 0.002). Patients in the hypomagnesemia group had a lower survival rate than those in the normal magnesium groups (p < 0.001). In a multivariate Cox proportional hazards regression analysis, serum magnesium was an independent negative predictor of all-cause mortality (hazard ratio [HR] = 0.075, p = 0.011) and cardiovascular mortality (HR = 0.003, p < 0.001), especially in female patients. However, in univariate and multivariate Cox analysis, △Mg(difference between 1-year magnesium and baseline magnesium) was not an independent predictor of all-cause mortality and cardiovascular mortality. CONCLUSION: Hypomagnesemia was common among peritoneal dialysis patients and was independently associated with all-cause mortality and cardiovascular mortality.