[Use of iron in nephrology: Results of a French practical survey]. / Utilisation du fer en néphrologie : enquête sur les pratiques des néphrologues français.

The French-speaking Society of Nephrology, Dialysis and Transplantation conducted, in 2018, a survey among French nephrologists into their iron prescribing habits for patients with chronic kidney disease stages 3 to 5 before dialysis. The results show that 73% of nephrologists use intravenous iron before dialysis stage. When a patient has gastrointestinal symptoms under oral iron therapy, only 48% of nephrologists use intravenous route. The starting thresholds for iron are for 78% of nephrologists a transferrin saturation <20% and for 80% a serum ferritin <100 µg/L. Only 14% start iron when a transferrin saturation <25% or higher and 29% start iron when serum ferritin <200 µg/L or higher. High dosages of iron (500 and 1000 mg) are used by 58% of nephrologists. Finally, about 30% of nephrologists refer to various barriers to intravenous iron prescription, such as cost, unavailability of intravenous iron in their facility or lack of day hospital unit. The correction of iron deficiency without anemia remains controversial. It is performed by only 43% of nephrologists. These results show an improvement of the practices compared to a 2006 survey. However, they indicate a sub-prescription of iron compared to the European recommendations which recommend a starting threshold of iron of transferrin saturation <25% and ferritinemia <200 µg/L in anemic patients not treated with erythropoietin-stimulating agents.

Randomized Clinical Trial of Sevelamer Carbonate on Serum Klotho and Fibroblast Growth Factor 23 in CKD.

BACKGROUND AND OBJECTIVES: Epidemiologic studies suggest that higher serum phosphaturic hormone fibroblast growth factor 23 levels are associated with increase morbidity and mortality. The aim of the FGF23 Reduction Efficacy of a New Phosphate Binder in CKD Trial was to evaluate the effect of sevelamer carbonate on serum C-terminal fibroblast growth factor 23 levels in normophosphatemic patients with CKD stage 3b/4. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Patients with CKD, eGFR between 45 and 15 ml/min per 1.73 m2, fasting serum phosphate concentration >3.1 mg/dl, and serum C-terminal fibroblast growth factor 23 >80 relative units/ml were included in our double-blind, placebo-controlled, randomized multicenter study. All patients received 100,000 IU cholecalciferol at time of randomization. Participants received either placebo or sevelamer carbonate 4.8 g daily during a 12-week period. Biologic parameters, including serum C-terminal fibroblast growth factor 23, intact fibroblast growth factor 23, and α-klotho, were evaluated at baseline and 12 weeks after inclusion. RESULTS: Of 96 screened patients, 78 (mean±SD age: 63±13 years old; 70% men; mean eGFR: 27±9 ml/min per 1.73 m2) met the inclusion criteria. At baseline, mean eGFR was 27±9 ml/min per 1.73 m2, mean serum phosphate level was 3.8±0.5 mg/dl, and median (interquartile range) serum C-terminal fibroblast growth factor 23 level was 157 (120-241) relative units/ml. After 12 weeks of treatment, urinary phosphate-to-creatinine ratio fell significantly in the sevelamer group. The sevelamer and placebo groups did not differ significantly in terms of median change in serum C-terminal fibroblast growth factor 23 levels: the median (interquartile range) change was 38 (-13-114) relative units/ml in the placebo group and 37 (-1-101) relative units/ml in the sevelamer group (P=0.77). There was no significant difference in serum intact fibroblast growth factor 23, α-klotho, or phosphate levels changes between the two groups. Serum total and LDL cholesterol levels fell significantly in the sevelamer group. CONCLUSIONS: In our double-blind, placebo-controlled, randomized study performed in normophosphatemic patients with CKD, a 12-week course of sevelamer carbonate significantly reduced phosphaturia without changing serum phosphorus but did not significantly modify serum C-terminal fibroblast growth factor 23 and intact fibroblast growth factor 23 or α-klotho levels.

Recent changes in therapeutic approaches and association with outcomes among patients with secondary hyperparathyroidism on chronic hemodialysis: the DOPPS study.

BACKGROUND AND OBJECTIVES: Elevated parathyroid hormone levels may be associated with adverse clinical outcomes in patients on dialysis. After the introduction of practice guidelines suggesting higher parathyroid hormone targets than those previously recommended, changes in parathyroid hormone levels and treatment regimens over time have not been well documented. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Using data from the international Dialysis Outcomes and Practice Patterns Study, trends in parathyroid hormone levels and secondary hyperparathyroidism therapies over the past 15 years and the associations between parathyroid hormone and clinical outcomes are reported; 35,655 participants from the Dialysis Outcomes and Practice Patterns Study phases 1-4 (1996-2011) were included. RESULTS: Median parathyroid hormone increased from phase 1 to phase 4 in all regions except for Japan, where it remained stable. Prescriptions of intravenous vitamin D analogs and cinacalcet increased and parathyroidectomy rates decreased in all regions over time. Compared with 150-300 pg/ml, in adjusted models, all-cause mortality risk was higher for parathyroid hormone=301-450 (hazard ratio, 1.09; 95% confidence interval, 1.01 to 1.18) and >600 pg/ml (hazard ratio, 1.23; 95% confidence interval, 1.12 to 1.34). Parathyroid hormone >600 pg/ml was also associated with higher risk of cardiovascular mortality as well as all-cause and cardiovascular hospitalizations. In a subgroup analysis of 5387 patients not receiving vitamin D analogs or cinacalcet and with no prior parathyroidectomy, very low parathyroid hormone (<50 pg/ml) was associated with mortality (hazard ratio, 1.25; 95% confidence interval, 1.04 to 1.51). CONCLUSIONS: In a large international sample of patients on hemodialysis, parathyroid hormone levels increased in most countries, and secondary hyperparathyroidism treatments changed over time. Very low and very high parathyroid hormone levels were associated with adverse outcomes. In the absence of definitive evidence in support of a specific parathyroid hormone target, there is an urgent need for additional research to inform clinical practice.

[IV iron or oral iron in anaemic patient with CKD]. / Administration orale ou intraveineuse de fer au cours de la maladie rénale chronique.

Population-based study demonstrated that iron deficiency is really frequent, and anaemia not rare. Nevertheless, iron deficiency afflicts anaemic patients at all stages of chronic kidney disease (CKD). Bioavailability of oral iron supplements is highly variable, particularly in case of CKD. Moreover, efficacy is in favour of intravenous (i.v.) iron over oral iron. And safety of i.v. iron sucrose is today definite. Finally, recommended targets, i.e. Hb > 11 g/dl and transferring saturation > 20%, necessitate i.v. iron.