Association between serum magnesium and risk factors of cardiovascular disease in hemodialysis patients.

INTRODUCTION: There are associations between serum magnesium level and some risk factors of cardiovascular disease and atherosclerosis, such as lipid profile, serum albumin, C-reactive protein, serum phosphorus, parathyroid hormone, and diabetes mellitus in hemodialysis patients. The aim of this study was to examine these associations. MATERIALS AND METHODS: This study was conducted on 103 patients with end-stage renal disease on maintenance hemodialysis. Laboratory assessment was performed before hemodialysis session in a 12-hour fasting state. Patients were divided into two groups according to their serum magnesium concentration < 2.6 mg/dL, n = 34 and >= 2.6 mg/dL, n = 69). RESULTS: The mean age of the patients was 57.4 +/- 15.4 years. The mean serum magnesium was 2.80 +/- 0.55 mg/dL (range, 1.7 mg/dL to 7 mg/dL). There were no significant differences in serum magnesium between patients with low and high values of high-density lipoprotein cholesterol, triglycerides, low-density lipoprotein cholesterol, and blood pressure. Of the 103 patients, 1 (1%) had hypomagnesemia, 41 (39.8%) had magnesium levels within normal range, and 61 (59.2%) had hypermagnesemia. Serum magnesium significantly correlated with plasma phosphorus level (r = 0.35, P < .001) and albumin (r = 0.24, P = .01). There were no correlations between serum magnesium level and age, body mass index, systolic blood pressure before dialysis, serum calcium, lipid profile, and apoprotein(a). CONCLUSIONS: In our cohort of hemodialysis patients, there were no correlations between serum magnesium levels and atherogenic lipids, serum calcium, or parathyroid hormone.

Plasma vitamin C concentrations in patients on routine hemodialysis and its relationship to patients' morbidity and mortality.

BACKGROUND: Some studies have hypothesized the protective role of vitamin C against cardiovascular disorders (CVD) in patients with end-stage renal disease (ESRD). This study was designed to assess plasma vitamin C concentration and its relationship to hemodialysis (HD) patients' morbidity and mortality. METHODS: Plasma vitamin C concentrations were assessed in HD patients using spectrophotometry and subjects were prospectively followed for up eighteen months for all-cause mortality. Any association between vitamin C concentration and patients' demographic data, co-morbidities, or the cause of ESRD were investigated using the Chi-square test. RESULTS: Ninety-one patients with a mean age of 56.7 ± 15.7 years were included in this study. The most frequent cause of ESRD was simultaneous hypertension and diabetes in 30 % of patients, followed by hypertension in 25.6 %, and diabetes in 11.1 %, respectively. About 34 % of patients had CVD as the most prevalent co-morbidity. Forty-nine patients (53.8 %) had low levels of vitamin C concentration. There was a significant relationship between vitamin C insufficiency and presence of any co-morbidity in HD patients (p < 0.05). There was a significant difference in vitamin C concentrations between patients without co-morbidities and those with cardiovascular ones (F[2,88]=3.447, p = 0.036). Twenty-two (24.2 %) patients died over a median duration of 227 days. There was a significant difference in time to death of patients with and without low levels of vitamin C concentration (p = 0.04). CONCLUSIONS: The results showed lower plasma vitamin C levels in HD patients who suffered any co-morbidity and sooner time to death in these patients.