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<b><i>Background:</i></b> Hypomagnesaemia is a cardiovascular (CV) risk factor in the general population. The aim of this study was to evaluate the relationship between pre-dialysis magnesium (Mg) and CV risk markers, [including pulse pressure (PP), left ventricular mass index (LVMI) and vascular calcifications (VC)], and mortality in haemodialysis (HD) patients. <b><i>Methods:</i></b> We performed a 48-month prospective study in 206 patients under pre-dilution haemodiafiltration with a dialysate Mg concentration of 1 mmol/l. <b><i>Results:</i></b> Lower Mg concentrations were predictors of an increased PP (≥65 mm Hg) (p = 0.002) and LVMI (≥140 g/m²) (p = 0.03) and of a higher VC score (≥3) (p = 0.01). Patients with Mg <1.15 mmol/l had a lower survival at the end of the study (p = 0.01). Serum Mg <1.15 mmol/l was an independent predictor of all-cause (p = 0.01) and CV mortality (p = 0.02) when adjusted for multiple CV risk factors. <b><i>Conclusions:</i></b> Lower Mg levels seem to be associated with increased CV risk markers, like PP, LVMI and VC, and with higher mortality in HD patients.

These results suggest that lower levels of [25(OH)D3] are a cardiovascular risk marker in HD patients, since they are strongly associated with higher BNP levels, increased PP and with the presence of vascular calcifications. The exact role of [25(OH)D3] deficiency on cardiovascular morbi-mortality needs to be clarified in large randomized controlled trials.

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Background/Aim: Bone alkaline phosphatase (bAP) is known to be an important biochemical marker of bone formation. Through the present study, we intended to find out whether there is any advantage in bAP determination, as a routine biochemical marker, besides intact parathyroid hormone (iPTH) in hemodialysis patients. Methods: In a population of 140 hemodialysis patients, bAP and iPTH were determined on four quarterly consecutive occasions. According to the values of iPTH (pg/ml) and bAP (ng/ml), patients were divided into four groups: group I: iPTH >200 and bAP >20, group II: iPTH >200 and bAP <20, group III: iPTH <200 and bAP <20 and group IV: iPTH <200 and bAP >20. Patients with higher serum phosphorus (P) (group A: p ≧7 mg/dl) were compared with those with lower serum P levels (group B: p <7 mg/dl). Results: The global correlation between iPTH and bAP (total evaluations, n = 503) was 0.32 (p < 0.001). Group IV patients tended to show a slight increase of serum aluminum (sAl) levels, which were 12.48 ± 5.35 µg/l higher than in the patients from group I (sAl = 9.97 ± 4.39 µg/l), group II (sAl = 10.86 ± 4.45 µg/l) or group III (sAl = 10.92 ± 3.92 µg/l). Significance values (Mann-Whitney) in each group, in comparison with group IV, were the following: group I: 0.004; group II: 0.062; group III: <0.001. Group A (n = 66) showed higher iPTH levels than group B (n = 430), although bAP and sAl were both similar in these two groups of patients (Mann-Whitney): iPTH (A) = 631.0 ± 487.7 vs. iPTH (B) = 253.3 ± 191.6, p < 0.001; bAP (A) = 22.9 ± 17.4 vs. bAP (B) = 20.4 ± 13.1, p = n.s.; sAl (A) = 10.2 ± 3.5 vs. sAl (B) = 10.8 ± 4.4, p = n.s. For similar Al and bAP values, group A showed a much stronger iPTH/bAP correlation than group B: r = 0.67 (p < 0.001) vs. r = 0.30 (p < 0.001), respectively. Conclusion: Although iPTH and bAP are frequently in agreement, it seems important to separate parathyroid activity given by iPTH, from bone remodelling reflected by bAP, in the presence of either a higher aluminum exposition or a well-controlled phosphatemia.

Rationale & Objective: Clinical practice guidelines for dietary intake in hemodialysis focus on individual nutrients. Little is known about associations of dietary patterns with survival. We evaluated the associations of dietary patterns with cardiovascular and all-cause mortality among adults treated by hemodialysis.

Background/Aim: Calcium acetate/magnesium carbonate (CaMg) is a recent phosphate binder that has been shown to have protective cardiovascular (CV) effects in animal models. The aim of this study was to evaluate the relationship between CaMg therapy and CV risk markers like pulse pressure (PP), left ventricular mass index (LVMI) and valvular calcifications compared to sevelamer or no phosphate binder (NPB) therapy in chronic hemodialysis (HD) patients. Methods: We performed a 48-month prospective study in 138 HD patients under hemodiafiltration with a dialysate Mg concentration of 0.5 mmol/l. Patients underwent treatment with CaMg or sevelamer for at least 36 months or NPB therapy. Demographic, clinical, biochemical and echocardiographic parameters were evaluated at baseline and after a 48-month period. Results: At the end of the study, patients who had taken CaMg showed a significant reduction in PP (p < 0.001), LVMI (p = 0.003), aortic (p = 0.004) and mitral valve calcifications (p = 0.03) compared with NPB patients. Patients under CaMg showed a significant reduction of PP (p < 0.001), LVMI (p = 0.01) and aortic valve calcifications (p = 0.02) compared to sevelamer patients. In a multivariable analysis, CaMg therapy was negatively associated with progression of LVMI (p = 0.02) and aortic valve calcifications (p = 0.01). Patients under CaMg showed higher serum Mg levels (0.93 ± 0.14 mmol/l) compared to patients under sevelamer (0.87 ± 0.13) or NPB patients (0.82 ± 0.12; p < 0.001). Conclusions: In prevalent HD patients, the use of CaMg over 48 months was associated with a reduction of PP and LVMI and with a stabilization of aortic valve calcifications. These protective and promising results of this new phosphate binder need to be confirmed in randomized controlled studies.

Background: Low levels of 25-hydroxyvitamin D [25(OH)D] are frequent in chronic kidney disease and are associated with adverse outcomes. The aim of this 5-year prospective study was to evaluate the effects of cholecalciferol supplementation on mineral metabolism, inflammation and cardiac parameters in hemodialysis (HD) patients. Methods: The study included 97 patients. Cholecalciferol was given after HD according to 25(OH)D baseline levels measured twice (end of winter and of summer). The 25(OH)D levels, circulating bone metabolism, inflammation parameters, brain natriuretic peptide (BNP), pulse pressure (PP), and left ventricular mass index (LVMI) were evaluated before and after supplementation. Results: There was a significant increase in 25(OH)D levels after supplementation (p < 0.001); however, serum calcium (p = 0.02), phosphorus (p = 0.018), and iPTH (p = 0.03) were decreased. Magnesium levels increased during the study (p = 0.03). A reduction in the number of patients under active vitamin D (p < 0.001) and in the dose and number of patients treated with darbepoetin (p = 0.02) was observed. Serum albumin increased (p < 0.001), and C-reactive protein decreased (p = 0.01). BNP (p < 0.001), PP (p = 0.007), and LVMI (p = 0.02) were significantly reduced after supplementation. Conclusions: Long-term cholecalciferol supplementation allowed correction of 25(OH)D deficiency, improved mineral metabolism with less use of active vitamin D, attenuated inflammation, reduced the dose of the erythropoiesis-stimulating agent, and improved cardiac dysfunction.