Activation of the Calcium Receptor by Calcimimetic Agents Is Preserved Despite Modest Attenuating Effects of Hyperphosphatemia.

BACKGROUND: Phosphorus levels in the range seen clinically among patients undergoing dialysis have been reported to attenuate calcium receptor activation and modify parathyroid hormone (PTH) release from isolated parathyroid glands in vitro. Some clinicians and providers of dialysis thus have suggested that calcimimetic agents are ineffective and should not be used to manage secondary hyperparathyroidism among those undergoing dialysis when serum phosphorus concentrations exceed certain threshold levels. METHODS: To determine whether hyperphosphatemia diminishes the therapeutic response to calcimimetic agents, we used data from large clinical trials to analyze the effects of etelcalcetide and cinacalcet to lower plasma PTH levels in individuals on hemodialysis who had secondary hyperparathyroidism and varying degrees of hyperphosphatemia. RESULTS: Plasma PTH levels declined progressively during 26 weeks of treatment with either etelcalcetide or cinacalcet without regard to the degree of hyperphosphatemia at baseline. However, with each calcimimetic agent, the decreases in PTH from baseline were less at each interval of follow-up during the trials among participants with serum phosphorus levels above one of three prespecified threshold values compared with those with serum phosphorus levels below these thresholds. CONCLUSIONS: These in vivo findings are the first in humans to support the idea that hyperphosphatemia attenuates calcium receptor activation by calcium ions and by calcimimetic agents. The effect of hyperphosphatemia on the responsiveness to calcimimetic agents appears relatively modest, however, and unlikely to be significant therapeutically. The efficacy of treatment with calcimimetic agents for lowering plasma PTH levels among those with secondary hyperparathyroidism remains robust despite substantial elevations in serum phosphorus.

Overview of the 2017 KDIGO CKD-MBD Update: Practice Implications for Adult Hemodialysis Patients.

Renal dietitians play a pivotal role in the ongoing management of chronic kidney disease in patients on hemodialysis. Awareness of changes to clinical practice guidelines that may impact laboratory parameters associated with chronic kidney disease-mineral and bone disorder is important for optimal patient care. In this article, the Kidney Disease: Improving Global Outcomes 2017 Clinical Practice Guideline Update recommendations related to the treatment of secondary hyperparathyroidism in adults on hemodialysis are reviewed and treatment implications for renal dietitians discussed. Specific attention is given to the integration of updated recommendations such as the use of calcimimetics as part of a combination approach to the existing treatment paradigm. Renal dietitians can directly apply the updated clinical recommendations in the evaluation of diet composition; food additives; medication adherence challenges with phosphate binder type and use and serial monitoring of phosphorus, calcium, and parathyroid hormone levels to inform clinical decisions on treatment options for patients.

Medication prescribing patterns in ambulatory haemodialysis patients: comparisons of USRDS to a large not-for-profit dialysis provider.

BACKGROUND: End-stage renal disease (ESRD) patients are prescribed numerous medications. The United States Renal Data System (USRDS) reported on medication prescribing patterns in 1998. Since then, several new medications, treatment guidelines and recommendations have been introduced. The objective was to analyse and compare haemodialysis (HD) patient medication prescribing patterns between the Dialysis Clinic, Inc. (DCI) database and the USRDS report. METHODS: Point-prevalent (01/01/03) medication use data from the DCI national database was obtained. Data collected included patient demographics, reason for and duration of ESRD, and medication listed on profile. All medications were classified similar to the USRDS and by where taken (clinic vs home). Medication prescribing patterns were compared between DCI and USRDS databases. Comparisons between age groups (<65 and >or=65 years) and diabetic status [diabetes mellitus (DM) vs non-DM] were made. RESULTS: There were 128 477 medication orders categorized in 10 474 patients. DCI patient demographics were similar to present USRDS patients except for fewer Hispanics (P<0.001). Patients were prescribed 12.3+/-5.0 (median 12) different medications (2.6+/-1.4 clinic medications and 10.0+/-4.5 home medications). This is higher than reported by USRDS (median 9 medications). Patient age did not influence number of medications used (P = 0.54). DM patients are prescribed more medications than non-DM (13.3+/-5.0 DM vs 11.6+/-4.8 non-DM; P<0.00001). All medication class prescribing patterns were markedly different. CONCLUSION: The data suggest that medication prescribing patterns in HD patients have changed. The audit identified appropriate and questionable prescribing patterns. Various prescribing patterns identified areas for improvement in care (e.g. increased use of aspirin, beta-blockers and hyperlipidaemia medications) and areas requiring further investigation (e.g. high use of anti-acid, benzodiazepine and non-aluminum/non-calcium phosphate-binding medications).

Medication-related problem type and appearance rate in ambulatory hemodialysis patients.

BACKGROUND: Hemodialysis (HD) patients are at risk for medication-related problems (MRP). The MRP number, type, and appearance rate over time in ambulatory HD patients has not been investigated. METHODS: Randomly selected HD patients were enrolled to receive monthly pharmaceutical care visits. At each visit, MRP were identified through review of the patient chart, electronic medical record, patient interview, and communications with other healthcare disciplines. All MRP were categorized by type and medication class. MRP appearance rate was determined as the number of MRP identified per month/number of months in study. The number of MRP per patient-drug exposures were determined using: [[(number of patients) x (mean number of medications)]/(number of months of study)] /number of MRP identified. Results were expressed as mean +/- standard deviation or percentages. RESULTS: Patients were 62.6 +/- 15.9 years old, had 6.4 +/- 2.0 comorbid conditions, were taking 12.5 +/- 4.2 medications, and 15.7 +/- 7.2 doses per day at baseline. Medication-dosing problems (33.5%), adverse drug reactions (20.7%), and an indication that was not currently being treated (13.5%) were the most common MRP. 5,373 medication orders were reviewed and a MRP was identified every 15.2 medication exposures. Overall MRP appearance rate was 0.68 +/- 0.46 per patient per month. CONCLUSION: MRP continue to occur at a high rate in ambulatory HD patients. Healthcare providers taking care of HD patients should be aware of this problem and efforts to avoid or resolve MRP should be undertaken at all HD clinics.

Drug record discrepancies in an outpatient electronic medical record: frequency, type, and potential impact on patient care at a hemodialysis center.

BACKGROUND: Patients who require hemodialysis take many drugs. Electronic drug records may be discrepant with what patients are actually taking. Record discrepancies are a potential source of drug-related problems. We sought to determine the extent to which drug record discrepancies occur in a hemodialysis population. METHODS: This was a prospective observational study of patients enrolled in a pharmacist clinic at an outpatient hemodialysis center from August-December 2001. Patients participated in monthly drug interviews conducted by a pharmacist, during which patient drug use was determined. Data collected consisted of patient demographics, drug type, and number of drugs. Drug record discrepancies were classified and assigned a potential drug-related problem. Results were compared with the electronic drug record. Patients with documented drug record discrepancies were compared with those patients for whom no discrepancy was identified. RESULTS: Over the 5-month period, 215 drug interviews were conducted in 63 patients. One hundred thirteen drug record discrepancies were identified in 38 patients (60%). Discrepancies (mean +/- SD 1.7 +/- 1.3, range 1-7) were identified during 65 drug interviews (30.2%). Electronic drug records were discrepant by one drug record, two drug records, and more than two drug records 60.0%, 26.2%, and 13.8% of the time, respectively. Drug record discrepancies placed patients at risk for adverse drug events and dosing errors in 49.6% and 34.5%, respectively, of 113 discrepancies. Patient age negatively correlated with the number of drug record discrepancies identified (r = -0.27, p = 0.04). CONCLUSIONS: Drug record discrepancies occur frequently among patients undergoing hemodialysis. Incorporation of a pharmacist into the patient care team may increase the accuracy of the electronic drug record and avert unnecessary drug-related problems.