Compliance with mineral metabolism targets in haemodialysis patients: moving backwards?

BACKGROUND: To standardize therapy and improve the clinical outcome for chronic haemodialysis (HD) patients, guidelines have been developed for mineral metabolism management. We evaluated compliance with different mineral metabolism guidelines. METHODS: 2,951 chronic HD patients from 61 dialysis centres in Spain were studied. Mineral metabolism management data from a 1-year period were analysed according to KDOQI, KDIGO, and Spanish guidelines. RESULTS: Only 1% (KDOQI), 6% (KDIGO) and 11% (Spanish guidelines) of patients continuously achieved total calcium (Ca), phosphate (P) and parathyroid hormone (PTH) target-range values during the year with higher percentages if we considered the 1-year average. The yearly Ca, P and iPTH average accomplished Spanish guidelines with different percentage among centres: CA 62-100%, P 59-91%, PTH 61-89%, and 28-77% considering all three targets together. The KDIGO guidelines recommend similar percentages except for P (33-77%). No differences were found related to eKt/V, online haemodiafiltration/HD, weight, body mass index, or dialysis vintage. They were only related to age, blood flow, effective treatment time, and dialysate calcium but without relevant clinical differences. Patients outside the target ranges generated significantly higher treatment costs. CONCLUSIONS: Compliance with mineral metabolism targets in HD patients was poor and showed a wide variation between treatment centres.

[How can we improve symptomatic hypotension in hemodialysis patients: cold dialysis vs isothermic dialysis]. / Cómo mejorar la hipotensión sintomática en hemodiálisis: diálisis fría versus diálisis isotérmica.

BACKGROUND: Symptomatic hypotension is the most frequent acute complication affecting patients during chronic hemodialysis treatment sessions. Many reports have demonstrated that the use of cool dialysate has a protective effect on blood pressure during hemodialysis treatments. In the present study, we investigated whether preventing the hyperthermic response had favourable effects on hemodynamic stability during the hemodialysis procedure while affording good tolerance to patients. METHODS: We investigated the effect of thermal control of dialysate on hemodynamic stability in hypotension-prone patients in our center. Patients were eligible for the study if they had symptomatic hypotensive episodes (> 3/12session/ month) during the screening phase. The study was designed with two phases for the same selected patients and two treatment arms, each phase lasting 4 weeks. In the first phase, we adjusted dialysate temperature on 36 masculineC for 12 sessions (cold dialysis) and in the second phase we used a device allowing the regulation of thermal balance (Blood Temperature Monitor; Fresenius Medical Care, Bad Homberg, Germany), that keep body temperature unchanged (isothermic dialysis). RESULTS: Nine HD patients were enrolled and completed the study. During the screening phase the mean ultrafiltration was 4 1% of dry weight, and blood pressure decreased from 9916 to 8016 mm Hg (p<0.001). In 5.01.7 sessions of 12 treatments were complicated by hypotension. In the first and second phase we observed a decrease of complicated treatments with symptomatic hypotension (5.01.7 versus 2.71.6 y 2.81.7; p<0.01). Both procedures: Cold dialysis and Isothermic dialysis was well tolerated by patients. CONCLUSION: Results show that active control of body temperature can significantly improve intradialytic tolerance in hypotension-prone patients.

Cumulative iron dose and resistance to erythropoietin.

INTRODUCTION: Optimizing anemia treatment in hemodialysis (HD) patients remains a priority worldwide as it has significant health and financial implications. Our aim was to evaluate in a large cohort of chronic HD patients in Fresenius Medical Care centers in Spain the value of cumulative iron (Fe) dose monitoring for the management of iron therapy in erythropoiesis-stimulating agent (ESA)-treated patients, and the relationship between cumulative iron dose and risk of hospitalization. METHODS: Demographic, clinical and laboratory parameters from EuCliD(®) (European Clinical Dialysis Database) on 3,591 patients were recorded including ESA dose (UI/kg/week), erythropoietin resistance index (ERI) [U.I weekly/kg/gr hemoglobin (Hb)] and hospitalizations. Moreover the cumulative Fe dose (mg/kg of bodyweight) administered over the last 2 years was calculated. Univariate and multivariate analyses were performed to identify the main predictors of ESA resistance and risk of hospitalization. Patients belonging to the 4th quartile of ERI were defined as hypo-responders. RESULTS: The 2-year iron cumulative dose was significantly higher in the 4th quartile of ERI. In hypo-responders, 2-year cumulative iron dose was the only iron marker associated with ESA resistance. At case-mix adjusted multivariate analysis, 2-year iron cumulative dose was an independent predictor of hospitalization risk. DISCUSSION: In ESA-treated patients cumulative Fe dose could be a useful tool to monitor the appropriateness of Fe therapy and to prevent iron overload. To establish whether the associations between cumulative iron dose, ERI and hospitalization risk are causal or attributable to selection bias by indication, clinical trials are necessary.

[Plasma renin activity, arterial blood pressure and response to beta-adrenergic blockade: a non-demostrated correlation. Practical view points (author's transl)]. / Actividad renina plasmática, presión arterial y respuesta al bloqueo beta-adrenérgico: una correlación no demostrada. Consideraciones prácticas.

Nineteen patients have been treated with timolol maleate (a non selective beta-blocking) and the decrease of their blood arterial pressure was correlated with the suppression of renine secretion. The patients which controlled their arterial pressure (63%) as well as those who did not (37%) showed a significative decrease of the plasmatic renine. The patients were diagnosed of essential hypertension, with normal renal function and formed an homogenous group. The sodium intake was similar in all of them. The results showed that although the beta-blocking can act in hypertensive patients through the suppression of the renine angiotensine system, this is not the only maintenance factor of the arterial pressure, nor its only way of action. A relevant point to be stressed in the possibility of ARP stimulation by walking, in spite of the beta-blocking, which means that this is not a total blocking or that there are other factors regulating the ARP secretion, and that act together with the autonomous nervous system.

[Paradoxical correlation between plasma renin activity and hypotensive effect of beta-adrenergic blocking (author's transl)]. / Correlación paradójica entre actividad renina plasmática y efecto hipotensor del bloqueo beta-adrenérgico.

A group of 39 patients has been divided in three categories according to their plasmatic renine activity and the correlation of the hipotensive answer to the Timolol Maleate (betadrenergic blocking). The control is more favourable in the normorreninemic than in the hiporreninemic patients and, paradoxically, even more than in the hyperreninemic. This unexpected answer is probably due to the lowest sodium intake of this last group. Hyperreninemia is more than a factor determining their basal hypertension: it is a regulation factor by hiposodic diet and probably, drug resistant. Nor quantitative neither qualitative correlation among the basal plasmatic renine activity and the hipotensive activity has been observed.