Comparison of oral and intravenous alfacalcidol in chronic hemodialysis patients.

BACKGROUND: Activated vitamin D is the mainstay of treatment for secondary hyperparathyroidism (SHPT) in chronic hemodialysis patients. However, the optimal route of administration is still debated. The aim of our study was to compare efficacy of oral vs intravenous (IV) administration of alfacalcidol in hemodialysis. A secondary objective was to determine the cost-effectiveness advantage of oral administration. METHODS: Eighty-eight chronic hemodialysis patients receiving IV alfacalcidol three times a week were included in the study. All were switched to the same dose of alfacalcidol given orally three times a week during the hemodialysis session. A budget impact analysis was performed. RESULTS: Mean patient age was 64 years old and 43% were males. The mean alfacalcidol dose administered was 2.1 µg three times a week. After three months, serum parathormone (PTH) levels decreased from 80 to 59 pmol/L (p = 0.001) and total serum calcium levels increased from 2.34 to 2.40 mmol/L (p = 0.002). After six months, total serum calcium levels were still significantly higher. Alfacalcidol dosage was significantly decreased during study period; the mean reduction was 0.44 µg per dose. Finally, oral administration was associated with an annual cost reduction of 197 678$CAN and an annual nursing time reduction of 25 days. CONCLUSION: Our findings support that switching IV to oral administration of alfacalcidol during hemodialysis sessions may lead to a similar control of SHPT with lower doses of activated vitamin D. This is a good strategy for optimizing compliance and may allow a dose reduction because of a greater efficacy to suppress PTH. Oral administration also has significant cost-effectiveness advantages.

Adherence to antihypertensive agents improves risk reduction of end-stage renal disease.

Uncontrolled hypertension is associated with an increased risk of end-stage renal disease (ESRD). Intensified blood pressure control may slow progression of chronic kidney disease; however, the impact of antihypertensive agent adherence on the prevention of ESRD has never been evaluated. Here we assessed the impact of antihypertensive agent adherence on the risk of ESRD in 185,476 patients in the RAMQ databases age 45 to 85 and newly diagnosed/treated for hypertension between 1999 and 2007. A case cohort study design was used to assess the risk of and multivariate Cox proportional models were used to estimate the adjusted hazard ratio of ESRD. Adherence level was reported as a medication possession ratio. Mean patient age was 63 years, 42.2% male, 14.0% diabetic, 30.3% dyslipidemic, and mean follow-up was 5.1 years. A high adherence level of 80% or more to antihypertensive agent(s) compared to a lower one was related to a risk reduction of ESRD (hazard ratio 0.67; 95% confidence intervals 0.54-0.83). Sensitivity analysis revealed that the effect is mainly in those without chronic kidney disease. Risk factors for ESRD were male, diabetes, peripheral artery disease, chronic heart failure, gout, previous chronic kidney disease, and use of more than one agent. Thus, our study suggests that a better adherence to antihypertensive agents is related to a risk reduction of ESRD and this adherence needs to be improved to optimize benefits.

Pentastarch 10% (250 kDa/0.45) is an independent risk factor of acute kidney injury following cardiac surgery.

UNLABELLED: OBJECTIVE, DESIGN AND PATIENTS: The risk of acute kidney injury (AKI) associated with hydroxyethyl starch may be limited to higher molecular weight agents. We retrospectively evaluated the risk of AKI using pentastarch 10% (250 kDa, 0.45) in a random cohort of 563 patients operated for a cardiac surgery at a university hospital. MEASURES: We assessed previously identified preoperative, perioperative, and postoperative risk factors, and the volume of pentastarch given until the end of the first postoperative day. We defined AKI by a 50% rise in serum creatinine within 4 days after surgery. Different propensity adjustment methods were used to further assess the selection bias. RESULTS: Fifty-four (10%) patients developed AKI. Risk factors of AKI were age, female gender, preoperative creatinine clearance, hypertension, diuretic use, left ventricular ejection fraction, valvular surgery, duration of extracorporeal circulation, duration and dose of postoperative vasopressor support, and the number of red blood cells and fresh frozen plasma transfusions. Patients with AKI received 16 +/- 9 mL/kg of pentastarch as opposed to 10 +/- 7 mL/kg in controls (p < 0.001). Pentastarch remained independently predictive of AKI, with an adjusted odds ratio per mL/kg of 1.08 (95% confidence interval 1.04-1.12, p = 0.001). This risk was dose-dependent, and the optimal cutoff volume predicting AKI was 14 mL/kg. Different propensity adjustment methods were tested, and pentastarch as a risk factor of AKI was identified. CONCLUSIONS: This study identified a dose-dependent risk of AKI with pentastarch following cardiac surgery, given until the end of the first postoperative day.

Enalapril reduces the incidence of diabetes in patients with chronic heart failure: insight from the Studies Of Left Ventricular Dysfunction (SOLVD).

BACKGROUND: Diabetes mellitus is a predictor of morbidity and mortality in patients with heart failure. The effect of angiotensin-converting enzyme (ACE) inhibitors on the prevention of diabetes in patients with left ventricular dysfunction is unknown. The aim of this retrospective study was to assess the effect of the ACE inhibitor enalapril on the incidence of diabetes in the group of patients from the Montreal Heart Institute enrolled in the Studies of Left Ventricular Dysfunction (SOLVD). METHODS AND RESULTS: Clinical charts were evaluated for fasting plasma glucose (FPG) levels by blinded reviewers. A diagnosis of diabetes was made when a FPG > or =126 mg/dL (7 mmol/L) was found at 2 visits (follow-up, 2.9+/-1.0 years). Of the 391 patients enrolled at the Montreal Heart Institute, 291 were not diabetic (FPG <126 mg/dL without a history of diabetes), 153 of these were on enalapril and 138 were on placebo. Baseline characteristics were similar in the 2 groups. Forty patients developed diabetes during follow-up, 9 (5.9%) in the enalapril group and 31 (22.4%) in the placebo group (P<0.0001). By multivariate analysis, enalapril remained the most powerful predictor for risk reduction of developing diabetes (hazard ratio, 0.22; 95% confidence intervals, 0.10 to 0.46; P<0.0001). The effect of enalapril was striking in the subgroup of patients with impaired FPG (110 mg/dL [6.1 mmol/L] < or =FPG <126 mg/dL) at baseline: 1 patient (3.3%) in the enalapril group versus 12 (48.0%) in the placebo group developed diabetes (P<0.0001). CONCLUSIONS: Enalapril significantly reduces the incidence of diabetes in patients with left ventricular dysfunction, especially those with impaired FPG.

Pathophysiology of chronic kidney disease-mineral and bone disorder.

Chronic kidney disease (CKD) alters the metabolism of several minerals, thereby inducing bone lesions and vessel-wall calcifications that can cause functional impairments and excess mortality. The histological bone abnormalities seen in CKD, known as renal osteodystrophy, consist of alterations in the bone turnover rate, which may be increased (osteitis fibrosa [OF]) or severely decreased (adynamic bone disease [AD]); abnormal mineralization (osteomalacia [OM]), and bone loss. Secondary hyperparathyroidism is related to early phosphate accumulation (responsible for FGF23 overproduction by bone tissue), decreased calcitriol production by the kidneys, and hypocalcemia. Secondary hyperparathyroidism is associated with OF. Other factors that affect bone include acidosis, chronic inflammation, nutritional deficiencies, and iatrogenic complications.