Differences in Phosphate and Parathyroid Hormone Concentrations over the Day among Patients on Hemodialysis.

BACKGROUND: Elevated serum phosphate and parathyroid hormone (PTH) concentrations are associated with cardiovascular events, bone disease, and mortality in patients on maintenance hemodialysis. Although circadian changes are known in people with CKD, it is unknown whether differences occur in these parameters over the course of a day in people receiving hemodialysis. METHODS: We used clinical data from Fresenius Medical Care US dialysis clinics to determine how the time of day when measurements were collected (hemodialysis treatment start time) may be associated with serum phosphate and PTH concentrations. We used harmonic regression to assess these associations while accounting for demographic data and treatment parameters. RESULTS: A total of 96,319 patients receiving maintenance hemodialysis were included in this analysis. Patients had a mean age of 64±14 years, 43% were women, and dialysis start times ranged from 3:00 am to 7:59 pm. The mean serum phosphate concentration was 5.2±1.5 mg/dl, and the median PTH was 351 pg/ml (interquartile range [IQR], 214-547). In fully adjusted models, serum phosphate had a nadir at 11:00 am of 4.97 (IQR, 4.94-5.01) mg/dl and a peak at 7:00 pm of 5.56 (IQR, 5.50-5.62) mg/dl. Serum PTH had a nadir at 9:00 am of 385 (IQR, 375-395) pg/ml and a peak at 7:00 pm of 530 (IQR, 516-547) pg/ml. CONCLUSIONS: Among patients receiving maintenance hemodialysis, concentrations of PTH and phosphate before a dialysis session vary with the time of day that these values are measured. Consideration of whether these values were obtained at peak or nadir times of the day may be important in treatment decisions.

Mineral bone disease in autosomal dominant polycystic kidney disease.

Mice with disruption of Pkd1 in osteoblasts demonstrate reduced bone mineral density, trabecular bone volume and cortical thickness. To date, the bone phenotype in adult patients with autosomal dominant polycystic kidney disease (ADPKD) with stage I and II chronic kidney disease has not been investigated. To examine this, we characterized biochemical markers of mineral metabolism, examined bone turnover and biology, and estimated risk of fracture in patients with ADPKD. Markers of mineral metabolism were measured in 944 patients with ADPKD and other causes of kidney disease. Histomorphometry and immunohistochemistry were compared on bone biopsies from 20 patients with ADPKD with a mean eGFR of 97 ml/min/1.73m2 and 17 healthy individuals. Furthermore, adults with end stage kidney disease (ESKD) initiating hemodialysis between 2002-2013 and estimated the risk of bone fracture associated with ADPKD as compared to other etiologies of kidney disease were examined. Intact fibroblast growth factor 23 was higher and total alkaline phosphatase lower in patients with compared to patients without ADPKD with chronic kidney disease. Compared to healthy individuals, patients with ADPKD demonstrated significantly lower osteoid volume/bone volume (0.61 vs. 1.21%) and bone formation rate/bone surface (0.012 vs. 0.026 µm3/µm2/day). ESKD due to ADPKD was not associated with a higher risk of fracture as compared to ESKD due to diabetes (age adjusted incidence rate ratio: 0.53 (95% confidence interval 0.31, 0.74) or compared to other etiologies of kidney disease. Thus, individuals with ADPKD have lower alkaline phosphatase, higher circulating intact fibroblast growth factor 23 and decreased bone formation rate. However, ADPKD is not associated with higher rates of bone fracture in ESKD.

Mortality and Hospitalizations among Sickle Cell Disease Patients with End-Stage Kidney Disease Initiating Dialysis.

BACKGROUND: Sickle cell disease (SCD) is the most common inherited hematological disorder and a well-described risk factor for end-stage kidney disease (ESKD). Mortality and hospitalizations among patients with SCD who develop ESKD remain understudied. Furthermore, prior studies focused only on SCD patients where ESKD was caused by SCD. We aimed to describe mortality and hospitalization risk in all SCD patients initiating dialysis and explore risk factors for mortality and hospitalization. METHODS: We performed a national observational cohort study of African American ESKD patients initiating dialysis (2000-2014) in facilities affiliated with a large dialysis provider. SCD was identified by diagnosis codes and matched to a reference population (non-SCD) by age, sex, dialysis initiation year, and geographic region of care. Sensitivity analyses were conducted by restricting to patients where SCD was recorded as the cause of ESKD. RESULTS: We identified 504 SCD patients (mean age: 47 ± 14 years; 48% females) and 1,425 reference patients (mean age: 46 ± 14 years; 49% females). The median follow-up was 2.4 (IQR 1.0-4.5) years. Compared to the reference, SCD was associated with higher mortality risk (hazard ratio 1.66; 95% confidence interval [CI]: 1.36-2.03) and higher hospitalization rates (incidence rate ratio 2.12; 95% CI: 1.88-2.38) in multivariable analyses. Exploratory multivariable mortality risk models showed the largest mortality risk attenuation with the addition of time-varying hemoglobin and high-dose erythropoietin, but the association of SCD with mortality remained significant. Sensitivity analyses (restricted to ESKD caused by SCD) also showed significant associations between SCD and mortality and hospitalizations, but with larger effect estimates. High-dose erythropoietin was associated with the highest risk for mortality and hospitalization in SCD. CONCLUSIONS: Among ESKD patients, SCD is associated with a higher risk for mortality and hospitalization, particularly in patients where SCD is identified as the cause of ESKD.

Phosphates in medications: Impact on dialysis patients
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Maintaining phosphorus balance in in-center hemodialysis (ICHD) patients is problematic despite recommended dietary restriction, dialysis, and phosphate binder use. Rarely is P content in prescribed medications considered, but this source should raise concern. Data was obtained from the Fresenius Kidney Care (FKC) electronic data warehouse Knowledge Center and MedReview-eRx accessed Surescripts, housing > 80% of US-filled prescriptions. Adult FKC ICHD patients prescribed ≥ 1 medication in the MedReview-eRx database were analyzed (695,759 prescriptions). Information collected included medication dose, dose unit, dose timing, strength, start and stop dates, refills, demographic information, admission history, and modality type. Numbers of patients, prescriptions by individual medication, and drug class were then analyzed. Medications prescribed > 100 times were reported. Median doses/day (number of tablets) were calculated for each medication (open order on randomly selected day). Phosphate content of medications taken in FKC clinics was assessed using routinely used pharmacology references, and potential resulting phosphate and pill burden were also calculated. The top five prescribed drug classes in FKC dialysis patients were calcium-channel blockers (22%), proton pump inhibitors (PPIs; 18%), acetaminophen-opioid (AO; 13%), angiotensin-converting enzyme inhibitors (ACEi; 10%), and α2-agonists (9%). The maximum phosphate added for different medications varied by manufacturer. For instance, at median daily doses, phosphate contributions from the top five medications prescribed were 112 mg for amlodipine, 116.2 mg from lisinopril, 6.7 mg from clonidine, 0 mg from acetaminophen, and 200 mg for omeprazole. Prescribing these together could increase the daily phosphate load by 428 mg, forcing the patient to exceed the recommended daily intake (RDI) with food and drink. Phosphate content in medications prescribed to HD patients can substantially contribute to the daily phosphate load and, in combination, may even exceed the daily recommended dietary phosphate intake. Healthcare providers should monitor all medications containing phosphate prescribed in order to minimize risk of uncontrolled hyperphosphatemia and poor adherence.
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One-Year Historical Cohort Study of the Phosphate Binder Sucroferric Oxyhydroxide in Patients on Maintenance Hemodialysis.

OBJECTIVE: The high pill burden of many phosphate binders (PBs) may contribute to increased prevalence of hyperphosphatemia and poor nutritional status observed among patients undergoing maintenance hemodialysis therapy. We examined the real-world effectiveness of sucroferric oxyhydroxide (SO), a PB with low pill burden, in managing serum phosphorus in patients with prevalent hemodialysis over a 1-year period. DESIGN: Historical cohort analyses of de-identified electronic medical records. SUBJECTS: In-center hemodialysis patients switched from another PB to SO therapy as part of routine care with 12 months of uninterrupted SO prescriptions recorded, and documented serum phosphorus levels were eligible for inclusion. Clinical data were extracted from a pharmacy service, FreseniusRx, database and Fresenius Kidney Care clinical data warehouse. MAIN OUTCOME MEASURES: Comparisons were made between the 91-day period before SO initiation (i.e., baseline) and the 4 consecutive 91-day intervals of SO treatment (Q1-Q4). Clinical measures included achievement of target phosphorus levels (≤5.5 mg/dL) and mean number of PB pills/day. RESULTS: Among 530 analyzed patients, the proportion achieving target serum phosphorus levels increased by >100% 1 year after switching to SO therapy, that is, from 17.7% at baseline to 24.5%, 30.5%, 36.4%, and 36.0% at Q1 through Q4, respectively (P < .0001 for all). Reductions in serum phosphorus were observed at all follow-up timepoints (P < .0001), irrespective of baseline PB. From a mean baseline PB pill burden of 8.5 pills/day, patients experienced an average 50% pill burden reduction during SO treatment (P < .0001). Phosphorus-attuned albumin and phosphorus-attuned protein intake (normalized protein catabolic rate) improved significantly after transition to SO (P < .0001). The effectiveness of SO was evident in prespecified subgroups of interest (i.e., black/African-American patients, Hispanic/Latino patients, and women). CONCLUSION: Among patients on hemodialysis, switching to SO resulted in a 2-fold greater likelihood of achieving target phosphorus levels while halving daily PB pill burden. Increases in phosphorus-attuned albumin and protein intake suggest improved nutritional status.

Association of Smoking Status With Mortality and Hospitalization in Hemodialysis Patients.

RATIONALE & OBJECTIVE: The relationship between tobacco smoking and comorbid condition outcomes in hemodialysis (HD) patients is not well understood. This study examined the association of tobacco smoking status with hospitalization and mortality in HD patients. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Adult HD patients at 2,223 US dialysis centers with HD vintage of 30 days or less who completed a tobacco smoking status survey as part of standard care between April 2013 and June 2015. PREDICTOR: Tobacco smoking category: never smoked, currently living with smoker, former smoker, moderate smoker (<1 pack per day), or heavy smoker (≥1 pack per day). OUTCOMES: Death and hospital admissions within 2 years of the tobacco smoking survey. ANALYTICAL APPROACH: Kaplan-Meier analysis and Cox proportional hazards regression for time to death; cumulative incidence function and Cox proportional hazards regression for time to first hospitalization; negative-binomial regression for number of hospitalizations. RESULTS: Of 22,230 patients studied, 13% were active smokers. Mortality probabilities increased with greater exposure to smoking (17%, 22%, 23%, and 27% for never, moderate, former, and heavy smokers, respectively; P<0.001), as did incidence rates for first hospitalization (23%, 27%, 27%, and 30%, respectively; P<0.001). Compared to never smoked, heavy smokers had the highest mortality rate (HR for heavy smokers, 1.41 [95% CI, 1.18-1.69]; HR for moderate smokers, 1.39 [95% CI, 1.24-1.55]; HR for former smokers, 1.19 [95% CI, 1.11-1.28]). Living with a smoker was not associated with mortality (HR, 0.93; 95% CI, 0.72-1.22). HRs for first hospitalization followed similar patterns. The incidence rate of mortality for active smokers with diabetes was 173.7/1,000 patient-years and 103.5/1,000 patient-years for those who never smoked (incidence rate ratio, 1.68; P<0.001). LIMITATIONS: Self-reported survey without detailed history of smoking/cessation. CONCLUSIONS: Risks for death and hospitalization are elevated among HD patients who smoke, being highest among younger individuals and those with diabetes. Second-hand smoke was not associated with poor clinical outcomes.

Real-World Scenario Improvements in Serum Phosphorus Levels and Pill Burden in Peritoneal Dialysis Patients Treated with Sucroferric Oxyhydroxide.

BACKGROUND: A database analysis was conducted to assess the effectiveness of sucroferric oxyhydroxide (SO) on lowering serum phosphorus and phosphate binder (PB) pill burden among adult peritoneal dialysis (PD) patients prescribed SO as part of routine care. METHODS: Adult PD patients (n = 258) prescribed SO through a renal pharmacy service were analyzed. Baseline was 3 months before SO prescription. SO-treated follow-up was for 6 months or until either a new PB was prescribed, SO was not refilled, PD modality changed, or patient was discharged. In-range serum phosphorus was defined as ≤5.5 mg/dL. RESULTS: At baseline, mean serum phosphorus was 6.59 mg/dL with 10 prescribed PB pills/day. The proportion of patients achieving in-range serum phosphorus increased by 72% from baseline to month 6. Prescribed PB pills/day decreased by 57% (10 at baseline to 4.3 at SO follow-up, p < 0.0001). The mean length of SO follow-up was 5.1 months; SO follow-up ended for 38, 27, and 50 patients at months 4, 5, and 6, respectively, due to no further PB fills, and for 10, 11, and 4 patients at months 4, 5, and 6, respectively, due to another PB prescribed. In patients with baseline serum phosphorus >5.5 mg/dL who achieved in-range serum phosphorus during SO follow-up for ≥1 quarter, a notable improvement in serum phosphorus (6.54 to 5.10 mg/dL, p < 0.0001) was observed, and there was a 53% reduction in PB pill burden (9.9 to 4.7, p < 0.0001). CONCLUSION: Among PD patients prescribed SO as part of routine care, improvements in serum phosphorus control and >50% reduction in PB pills/day were observed.

Real-world effectiveness of sucroferric oxyhydroxide in patients on chronic hemodialysis: A retrospective analysis of pharmacy data
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AIMS: Hyperphosphatemia has been associated with an increased risk of mortality in patients with end-stage renal disease. We sought to assess the real-world effectiveness of sucroferric oxyhydroxide (SO), an iron-based phosphate binder (PB), in control of serum phosphorus levels, and to determine the associated pill burden in hemodialysis patients. MATERIALS AND METHODS: Adult, in-center hemodialysis patients first prescribed SO through a renal pharmacy service as part of routine clinical care between April 1, 2014 and March 31, 2015 were included in the analysis. The proportion of patients with phosphorus levels ≤ 5.5 mg/dL and the mean prescribed PB pills/day were compared between baseline (3 months prior to SO) and SO follow-up at 3 (SO 1 - 3) and 6 months (SO 4 - 6). Mineral bone disease markers, hemoglobin, iron indices, and erythropoiesis-stimulating agents and intravenous iron use were assessed. RESULTS: At baseline, all patients (n = 1,029) were prescribed PB, and 13.9% had mean serum phosphorus ≤ 5.5 mg/dL. Comparing baseline to SO 1 - 3, the mean prescribed PB pills/day declined from 9.6 to 3.8 pills/day (p < 0.001), and the proportion of patients with serum phosphorus ≤ 5.5 mg/dL increased from 13.9 to 26.1% (+88%). Comparing baseline to SO 4 - 6 (n = 424), the mean prescribed PB pills/day declined from 9.7 to 4.0 pills/day (p < 0.001), and the proportion of patients with serum phosphorus ≤ 5.5 mg/dL increased from 15.6 to 30.4% (+95%). CONCLUSIONS: Prescription of SO was associated with an increase in the proportion of patients achieving serum phosphorus levels ≤ 5.5 mg/dL along with fewer prescribed PB pills/day.
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Survival with three-times weekly in-center nocturnal versus conventional hemodialysis.

Whether the duration of hemodialysis treatments improves outcomes remains controversial. Here, we evaluated survival and clinical changes associated with converting from conventional hemodialysis (mean=3.75 h/treatment) to in-center nocturnal hemodialysis (mean=7.85 h/treatment). All 959 consecutive patients who initiated nocturnal hemodialysis for the first time in 77 Fresenius Medical Care facilities during 2006 and 2007 were eligible. We used Cox models to compare risk for mortality during 2 years of follow-up in a 1:3 propensity score-matched cohort of 746 nocturnal and 2062 control patients on conventional hemodialysis. Two-year mortality was 19% among nocturnal hemodialysis patients compared with 27% among conventional patients. Nocturnal hemodialysis associated with a 25% reduction in the risk for death after adjustment for age, body mass index, and dialysis vintage (hazard ratio=0.75, 95% confidence interval=0.61-0.91, P=0.004). With respect to clinical features, interdialytic weight gain, albumin, hemoglobin, dialysis dose, and calcium increased on nocturnal therapy, whereas postdialysis weight, predialysis systolic blood pressure, ultrafiltration rate, phosphorus, and white blood cell count declined (all P<0.001). In summary, notwithstanding the possibility of residual selection bias, conversion to treatment with nocturnal hemodialysis associates with favorable clinical features, laboratory biomarkers, and improved survival compared with propensity score-matched controls. The potential impact of extended treatment time on clinical outcomes while maintaining a three times per week hemodialysis schedule requires evaluation in future clinical trials.

Intensive hemodialysis associates with improved survival compared with conventional hemodialysis.

Patients undergoing conventional maintenance hemodialysis typically receive three sessions per week, each lasting 2.5-5.5 hours. Recently, the use of more intensive hemodialysis (>5.5 hours, three to seven times per week) has increased, but the effects of these regimens on survival are uncertain. We conducted a retrospective cohort study to examine whether intensive hemodialysis associates with better survival than conventional hemodialysis. We identified 420 patients in the International Quotidian Dialysis Registry who received intensive home hemodialysis in France, the United States, and Canada between January 2000 and August 2010. We matched 338 of these patients to 1388 patients in the Dialysis Outcomes and Practice Patterns Study who received in-center conventional hemodialysis during the same time period by country, ESRD duration, and propensity score. The intensive hemodialysis group received a mean (SD) 4.8 (1.1) sessions per week with a mean treatment time of 7.4 (0.87) hours per session; the conventional group received three sessions per week with a mean treatment time of 3.9 (0.32) hours per session. During 3008 patient-years of follow-up, 45 (13%) of 338 patients receiving intensive hemodialysis died compared with 293 (21%) of 1388 patients receiving conventional hemodialysis (6.1 versus 10.5 deaths per 100 person-years; hazard ratio, 0.55 [95% confidence interval, 0.34-0.87]). The strength and direction of the observed association between intensive hemodialysis and improved survival were consistent across all prespecified subgroups and sensitivity analyses. In conclusion, there is a strong association between intensive home hemodialysis and improved survival, but whether this relationship is causal remains unknown.

Kidney Health Initiative ESKD Data Standards Project.

The end-stage kidney disease (ESKD) Data Standards Project was launched by the Kidney Health Initiative (KHI) with the goal of standardizing dialysis-related measurements for research use. KHI is a public-private partnership between the American Society of Nephrology, US Food and Drug Administration, and organizations with an interest in kidney disease. KHI promotes safe and effective patient-centered therapies for people with kidney disease. In 2018, KHI established a workgroup with expertise in nephrology, nursing, quality management, ESKD data, organizational management, and clinical research. The workgroup identified 5 topic areas and 8 specific measures for the development of standards on the basis of the existing ESKD Measurement Specification Manual published by the Centers for Medicare & Medicaid Services. The topic areas were ultrafiltration rate, vascular access, dialysis small solute clearance (3 data standards), hospitalization (2 data standards), and mortality. The research standards were approved by the workgroup, reviewed by external reviewers, and opened to public comment. The data standards attempt to achieve balance between brevity and completeness in the face of knowledge gaps. The ESKD Data Standards are publicly available on the KHI website (https://khi.asn-online.org/projects/project.aspx?ID=78).

Anemia management in patients receiving chronic hemodialysis.

Anemia treatment in hemodialysis-dependent (HDD) CKD patients involves adequate supply of iron and an erythropoiesis-stimulating agent (ESA). Despite widespread usage of these agents, there is no generally accepted "standard dosing algorithm" for treating anemia in HDD-CKD patients. The new anemia Quality Incentive Program (QIP) introduced by the Centers for Medicare & Medicaid Services represents a motivation to standardize and harmonize iron and ESA regimens with interactive electronic algorithms and novel modes of deliveries for IV iron and ESA doses. In addition, quality assessment and performance improvement programs at dialysis facilities include achieving measurable improvement in health outcomes, healthcare cost, and reductions in medical errors. Thus, the Corporate Medical Advisory Board for Fresenius Medical Services (FMS) is evaluating an anemia algorithm that will be incorporated into the automated workflow of a new clinical system at FMS clinics. In the future, such systems might communicate with medication pumps incorporated into state-of-the-art HD machines, thereby eliminating manual data entry of medication orders and other potential errors related to data entry or administration of medications such as ESA and IV iron. In addition, the CritLine III TQA Monitor, which allows real-time blood volume, oxygen, and anemia monitoring during HD in acute and chronic settings, may become an integrated diagnostic tool to improve volume and anemia management through better fluid management and ESA dose adjustment algorithms. These novel interactive electronic algorithms, delivery and monitoring methods, and data transfer may be integrated in the Pharmatech process to meet patient-specific anemia therapy.

Application of kinetic modeling to mineral metabolism management.

Patients with CKD face many consequences of renal failure, including disorders of bone and mineral metabolism. The current approach to management of these mineral metabolism issues lacks comprehensive quantitative assessment, so a kinetic modeling program has been designed to quantify intake and removal of phosphorus and calcium, as well as provide recommendations for treatment and prescriptions based on total mass balance and serum concentrations. This program is known as phosphorus kinetic modeling or PKM. The modeling program and associated graphical reports have been developed as a tool for clinicians in the management of mineral metabolism in CKD patients.

Conversion from Intravenous Vitamin D Analogs to Oral Calcitriol in Patients Receiving Maintenance Hemodialysis.

BACKGROUND AND OBJECTIVES: In the United States, intravenous vitamin D analogs are the first-line therapy for management of secondary hyperparathyroidism in hemodialysis patients. Outside the United States, oral calcitriol (1,25-dihydroxyvitamin D3) is routinely used. We examined standard laboratory parameters of patients on in-center hemodialysis receiving intravenous vitamin D who switched to oral calcitriol. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a retrospective cohort study of adult patients treated within Fresenius Kidney Care clinics. During a 6-month period (December 2013 to May 2014), we identified patients on an intravenous vitamin D analog (doxercalciferol or paricalcitol) who switched to oral calcitriol and matched them to patients receiving an intravenous vitamin D analog. Mean serum calcium, phosphate, and intact parathyroid hormone (iPTH) concentrations were examined for up to 12 months of follow-up. We used Poisson and Cox proportional hazards regression models to examine hospitalization and survival rates. The primary analysis was conducted as intention-to-treat; secondary analyses included an as-treated evaluation. RESULTS: A total of 2280 patients who switched to oral calcitriol were matched to 2280 patients receiving intravenous vitamin D. Compared with patients on intravenous vitamin D, mean calcium and phosphate levels in the oral calcitriol group were lower after the change to oral calcitriol. In contrast, iPTH levels were higher in the oral calcitriol group. At 12 months, the percentage of patients with composite laboratories in target range (calcium <10 mg/dl, phosphate 3.0-5.5 mg/dl, and iPTH 150-600 pg/ml) were comparable between groups (45% versus 45%; P=0.96). Hospital admissions, length of hospital stay, and survival were comparable between groups. An as-treated analysis and excluding those receiving cinacalcet did not reveal significant between-group differences. CONCLUSIONS: Among patients receiving in-center hemodialysis who were switched to oral calcitriol versus those on an intravenous vitamin D analog, the aggregate of all mineral and bone laboratory parameters in range was largely similar between groups.

The International Quotidian Dialysis Registry: Annual report 2008.

Alternative hemodialysis (HD) schedules, including short-daily and nocturnal HD, continue to proliferate, with the hope of offering improved patient outcomes. Three nights per week and every other night, nocturnal HD are now being provided to more patients worldwide, both at home and in-center. However, alternative HD schedules are still experimental in most centers, and studies establishing the efficacy of these therapies with respect to major clinical outcomes are needed. Endorsed by the National Institutes of Health, the International Quotidian Dialysis Registry is an international collaboration that was established in 2002 to prospectively study large numbers of patients treated with alternate HD schedules. The Registry will ultimately allow alternate HD modalities to be compared to conventional thrice-weekly HD with respect to clinical endpoints, including mortality, using a prospective cohort study. To date, the Registry has enrolled 182, 1193, and 740 subjects from Canada, the United States, and Australia, respectively. This report is the fourth annual update and describes recruitment progress, baseline characteristics of enrolled patients, and worldwide prescription patterns.

Survival of patients undergoing hemodialysis with paricalcitol or calcitriol therapy.

BACKGROUND: Elevated calcium and phosphorus levels after therapy with injectable vitamin D for secondary hyperparathyroidism may accelerate vascular disease and hasten death in patients undergoing long-term hemodialysis. Paricalcitol, a new vitamin D analogue, appears to lessen the elevations in serum calcium and phosphorus levels, as compared with calcitriol, the standard form of injectable vitamin D. METHODS: We conducted a historical cohort study to compare the 36-month survival rate among patients undergoing long-term hemodialysis who started to receive treatment with paricalcitol (29,021 patients) or calcitriol (38,378 patients) between 1999 and 2001. Crude and adjusted survival rates were calculated and stratified analyses were performed. A subgroup of 16,483 patients who switched regimens was also evaluated. RESULTS: The mortality rate among patients receiving paricalcitol was 3417 per 19,031 person-years (0.180 per person-year), as compared with 6805 per 30,471 person-years (0.223 per person-year) among those receiving calcitriol (P<0.001). The difference in survival was significant at 12 months and increased with time (P<0.001). In the adjusted analysis, the mortality rate was 16 percent lower (95 percent confidence interval, 10 to 21 percent) among paricalcitol-treated patients than among calcitriol-treated patients. A significant survival benefit was evident in 28 of 42 strata examined, and in no stratum was calcitriol favored. At 12 months, calcium and phosphorus levels had increased by 6.7 and 11.9 percent, respectively, in the paricalcitol group, as compared with 8.2 and 13.9 percent, respectively, in the calcitriol group (P<0.001). The two-year survival rate among patients who switched from calcitriol to paricalcitol was 73 percent, as compared with 64 percent among those who switched from paricalcitol to calcitriol (P=0.04). CONCLUSIONS: Patients who receive paricalcitol while undergoing long-term hemodialysis appear to have a significant survival advantage over those who receive calcitriol. A prospective, randomized study is critical to confirm these findings.

The epidemiology of systolic blood pressure and death risk in hemodialysis patients.

BACKGROUND: This study compares the associations of predialysis systolic blood pressure (SBP) with mortality risk in both incident and prevalent hemodialysis (HD) cohorts by using both conventional and time-varying Cox analyses, thus addressing limitations of prior studies. METHODS: A total of 56,338 incident patients starting HD therapy during 1997 to 2001 and 69,590 prevalent HD patients on January 1, 2002, were grouped into the following categories: (1) SBP less than 120 mm Hg, (2) 120 < or = SBP < 140 mm Hg, (3) 140 < or = SBP < 160 mm Hg, (4) 160 < or = SBP < 180 mm Hg, (5) 180 < or = SBP < 200 mm Hg, and (6) SBP of 200 mm Hg or greater. Conventional and time-varying models evaluated 1-year and 3-year (incident patients only) survival. RESULTS: Nine percent and 26.0% of incident patients and 5.7% and 20.1% of prevalent patients were in categories 1 and 2, respectively. Their associated 1-year hazard ratios (HRs) were 2.63 to 3.68 and 1.57 to 1.68 compared with category 4, the reference group. HRs for categories 3, 5, and 6 were not different from category 4. Time-varying models magnified category 1 and 2 HRs to 5.54 to 7.42 and 1.92 to 2.21, such that 25% to 35% of patients in the target SBP range (< 140 mm Hg) had the greatest risk. A "reversed J-shaped" risk profile emerged in the time-varying models, with very high SBP (category 6) associated with HRs of 1.52 to 1.55, but only 1% of patients were in category 6. Three-year outcomes were similar. CONCLUSION: Epidemiological characteristics of predialysis SBP consistently differ from those in the general population despite different analytic perspectives. The data suggest a need for greater investigative, diagnostic, and therapeutic focus on HD patients with normal and prehypertensive blood pressure ranges.

Epoetin alfa use in patients with ESRD: an analysis of recent US prescribing patterns and hemoglobin outcomes.

BACKGROUND: It is unknown to what degree physicians adjust erythropoietin doses to achieve hemoglobin levels (11.0 to 12.0 g/dL [110 to 120 g/L]) recommended by the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI) for patients with end-stage renal disease receiving hemodialysis. Our objective is to examine epoetin alfa prescribing patterns for achieving the target hemoglobin level range in this population. METHODS: Monthly hemoglobin levels and epoetin alfa doses from 2 large databases were retrospectively analyzed. One data set comprised 31,267 patients from the Fresenius Medical Care-North America (FMC-NA) database, and the other comprised 128,761 patients based on claims for Medicare services. RESULTS: Longitudinal evaluation of the FMC-NA data set showed that hemoglobin levels in patients administered epoetin alfa cycled in and out of the NKF-K/DOQI hemoglobin target range, and doses were decreased in 98.8% of patients with persistent hemoglobin levels greater than 12.0 g/dL (> 120 g/L). Hemoglobin levels in patients from the Medicare data set that initially were outside the target range migrated into the range with epoetin alfa dose titration. FMC-NA patients with a 3-month average hemoglobin level less than 11.0 g/dL (< 110 g/L) were administered significantly greater epoetin alfa doses than those with average hemoglobin levels greater than 12.0 g/dL (> 120 g/L; 21,838 versus 13,503 U/wk; P < 0.0001). Less than 0.4% of patients administered epoetin alfa were persistently anemic (hemoglobin < 11.0 g/dL [< 110 g/L]) and were administered persistently high doses (> 30,000 U/wk), but failed to respond with a 0.5-g/dL or greater (> or = 5-g/L) increase in hemoglobin levels. CONCLUSION: In these analyses, few hemodialysis patients experienced persistent anemia while being administered high epoetin alfa doses. Physicians appeared to appropriately adjust doses to achieve hemoglobin levels recommended by the NKF-K/DOQI guidelines.

Antibody response to Engerix-B and Recombivax-HB hepatitis B vaccination in end-stage renal disease.

Recombivax-HB (REC) and Engerix-B (ENG) are FDA-approved vaccines for hepatitis B virus (HBV) in end-stage renal disease (ESRD). This study compares antibody response rates between them in routine clinical practice. Patients completing the recommended 40 mug dose of REC (3 doses) or ENG (4 doses) between January 1, 2000 to April 30, 2003 were eligible. Patients with prior positive HBV surface antigen (HBsAg) or antibody (HBsAb) test results were excluded. The conversion rate and persistence of protective titer (HBsAb titer>or=10 IU/mL) were tracked for 1 year. A supplemental analysis of a one-to-one matched patient sample was also performed. REC patients (N=885) were older, had longer dialysis vintage, and had a larger proportion of whites than ENG patients (N=13,661). Cumulative conversion response was greater in ENG (58%) than REC (40%) at 1 year (p<0.0001). The odds ratio for response to ENG compared with REC was 1.96 (95% limits: 1.56, 2.45; p<0.0001) adjusted for age, gender, race, diabetes, vintage, BSA, hemoglobin, and eKt/V. Persistent protective HBsAb after 1 year was 77% (ENG) vs. 53% (REC). HBsAg was positive in 208 ENG patients (1.5%) with all but 1 because of transient, vaccine-related antigenemia. The difference in conversion response favoring ENG persisted in a one-to-one sample matched for age, gender, race, modality, and dialysis vintage. The study found higher seroconversion response to ENG compared with REC at several time points up to 1 year. Protective HBsAb disappeared in 23-47% of patients 1 year later, validating CDC recommendations to re-test HBsAb yearly. The observed difference in response rates may be related to the extra ENG dose given at the second month (0, 1, 2, 6 regimen). The study raises a hypothesis that requires confirmation in a prospective clinical trial.

Effect of variability in anemia management on hemoglobin outcomes in ESRD.

BACKGROUND: Hemoglobin (Hgb) levels fluctuate in patients with end-stage renal disease over time. This study quantified Hgb level variability and the likelihood of falling within the Hgb level goal range of 11 to 12 g/dL. Implications on the percentage of patients exceeding 3-month rolling average Hgb levels of 12, 12.5, and 13 g/dL were determined. METHODS: Phase I (n = 65,009) tracked patients with Hgb values initially outside the goal range (<11 or >12 g/dL) during 2000. Correlation with facility-specific thresholds also was evaluated. Phase II (n = 48,133) quantified variation in 3-month rolling average Hgb levels in a subset with greater than 10 months of data (mean Hgb, 11.4 +/- 1.3 g/dL). RESULTS: A total of 24,948 patients (38.4%) had Hgb levels between 11 and 12 g/dL. In only 8% did Hgb levels consistently remain less than 11 g/dL, and in 18%, greater than 12 g/dL all year. Twenty-nine percent (18,633 patients) moved from below to above target range or vice versa. Greater mean facility Hgb level correlated with a greater percentage of patients with Hgb levels greater than 10 g/dL (R2 = 0.49) and greater than 12.5 g/dL (R2 = 0.61). For facilities to have 90% or greater of patients with 3-month rolling average Hgb levels greater than 10 g/dL, 13% to 31% of patients will have 3-month rolling average Hgb values greater than 12.5 g/dL. The average individual patient is expected to have a +/-1.4-g/dL fluctuation in 3-month rolling average Hgb levels per year. Despite increased mean Hgb levels and erythropoietin (EPO) and iron use, the spread of the Hgb distribution curve remained unchanged in the last 6 years. CONCLUSION: Variability caused by laboratory assays, biological factors, and therapeutic response determines patient Hgb level variability. Improving factors that can be manipulated (eg, standardizing EPO and iron algorithms) and adjustment of the target Hgb level range, specifically, by increasing the upper bound, likely will decrease the observed variability and further enhance the quality of anemia management.