David C Wheeler

University College London, Londinium, England, United Kingdom

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Publications (89)644.08 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Fractures are frequent in patients receiving hemodialysis. We tested the hypothesis that cinacalcet would reduce the rate of clinical fractures in patients receiving hemodialysis using data from the Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events trial, a placebo-controlled trial that randomized 3883 hemodialysis patients with secondary hyperparathyroidism to receive cinacalcet or placebo for ≤64 months. This study was a prespecified secondary analysis of the trial whose primary end point was all-cause mortality and non-fatal cardiovascular events, and one of the secondary end points was first clinical fracture event. Clinical fractures were observed in 255 of 1935 (13.2%) patients randomized to placebo and 238 of 1948 (12.2%) patients randomized to cinacalcet. In an unadjusted intention-to-treat analysis, the relative hazard for fracture (cinacalcet versus placebo) was 0.89 (95% confidence interval [95% CI], 0.75 to 1.07). After adjustment for baseline characteristics and multiple fractures, the relative hazard was 0.83 (95% CI, 0.72 to 0.98). Using a prespecified lag-censoring analysis (a measure of actual drug exposure), the relative hazard for fracture was 0.72 (95% CI, 0.58 to 0.90). When participants were censored at the time of cointerventions (parathyroidectomy, transplant, or provision of commercial cinacalcet), the relative hazard was 0.71 (95% CI, 0.58 to 0.87). Fracture rates were higher in older compared with younger patients and the effect of cinacalcet appeared more pronounced in older patients. In conclusion, using an unadjusted intention-to-treat analysis, cinacalcet did not reduce the rate of clinical fracture. However, when accounting for differences in baseline characteristics, multiple fractures, and/or events prompting discontinuation of study drug, cinacalcet reduced the rate of clinical fracture by 16%-29%. Copyright © 2014 by the American Society of Nephrology.
    Journal of the American Society of Nephrology 12/2014; · 9.47 Impact Factor
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    Nitric Oxide 11/2014; 42C:130-131. · 3.18 Impact Factor
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    ABSTRACT: Premature cardiovascular disease limits the duration and quality of life on long-term hemodialysis. The objective of this study was to define the frequency of fatal and nonfatal cardiovascular events attributable to atherosclerotic and nonatherosclerotic mechanisms, risk factors for these events, and the effects of cinacalcet, using adjudicated data collected during the EValuation of Cinacalcet HCl Therapy to Lower CardioVascular Events (EVOLVE) Trial. EVOLVE was a randomized, double-blind, placebo-controlled clinical trial that randomized 3883 hemodialysis patients with moderate to severe secondary hyperparathyroidism to cinacalcet or matched placebo for up to 64 months. For this post hoc analysis, the outcome measure was fatal and nonfatal cardiovascular events reflecting atherosclerotic and nonatherosclerotic cardiovascular diseases. During the trial, 1518 patients experienced an adjudicated cardiovascular event, including 958 attributable to nonatherosclerotic disease. Of 1421 deaths during the trial, 768 (54%) were due to cardiovascular disease. Sudden death was the most frequent fatal cardiovascular event, accounting for 24.5% of overall mortality. Combining fatal and nonfatal cardiovascular events, randomization to cinacalcet reduced the rates of sudden death and heart failure. Patients randomized to cinacalcet experienced fewer nonatherosclerotic cardiovascular events (adjusted relative hazard 0.84, 95% CI 0.74 to 0.96), while the effect of cinacalcet on atherosclerotic events did not reach statistical significance. Accepting the limitations of post hoc analysis, any benefits of cinacalcet on cardiovascular disease in the context of hemodialysis may result from attenuation of nonatherosclerotic processes. Unique identifier: NCT00345839. URL: ClinicalTrials.gov. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
    Journal of the American Heart Association. 10/2014; 3(6).
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    ABSTRACT: Patients with chronic kidney disease (CKD) are unlikely to gain the same benefit from conventional doses of statins as do patients with cardiovascular disease alone. This study investigated whether inflammation accompanying CKD causes statin resistance.
    Nephrology Dialysis Transplantation 06/2014; 29(10). · 3.49 Impact Factor
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    ABSTRACT: Lowering LDL cholesterol reduces the risk of developing atherosclerotic events in CKD, but the effects of such treatment on progression of kidney disease remain uncertain. Here, 6245 participants with CKD (not on dialysis) were randomly assigned to simvastatin (20 mg) plus ezetimibe (10 mg) daily or matching placebo. The main prespecified renal outcome was ESRD (defined as the initiation of maintenance dialysis or kidney transplantation). During 4.8 years of follow-up, allocation to simvastatin plus ezetimibe resulted in an average LDL cholesterol difference (SEM) of 0.96 (0.02) mmol/L compared with placebo. There was a nonsignificant 3% reduction in the incidence of ESRD (1057 [33.9%] cases with simvastatin plus ezetimibe versus 1084 [34.6%] cases with placebo; rate ratio, 0.97; 95% confidence interval [95% CI], 0.89 to 1.05; P=0.41). Similarly, allocation to simvastatin plus ezetimibe had no significant effect on the prespecified tertiary outcomes of ESRD or death (1477 [47.4%] events with treatment versus 1513 [48.3%] events with placebo; rate ratio, 0.97; 95% CI, 0.90 to 1.04; P=0.34) or ESRD or doubling of baseline creatinine (1189 [38.2%] events with treatment versus 1257 [40.2%] events with placebo; rate ratio, 0.93; 95% CI, 0.86 to 1.01; P=0.09). Exploratory analyses also showed no significant effect on the rate of change in eGFR. Lowering LDL cholesterol by 1 mmol/L did not slow kidney disease progression within 5 years in a wide range of patients with CKD.
    Journal of the American Society of Nephrology 05/2014; · 9.47 Impact Factor
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    ABSTRACT: The incidence and prevalence of diabetes mellitus (DM) continue to grow markedly throughout the world, due primarily to the increase in type 2 DM (T2DM). Although improvements in DM and hypertension management have reduced the proportion of diabetic individuals who develop chronic kidney disease (CKD) and progress to end-stage renal disease (ESRD), the sheer increase in people developing DM will have a major impact on dialysis and transplant needs. This KDIGO conference addressed a number of controversial areas in the management of DM patients with CKD, including aspects of screening for CKD with measurements of albuminuria and estimated glomerular filtration rate (eGFR); defining treatment outcomes; glycemic management in both those developing CKD and those with ESRD; hypertension goals and management, including blockers of the renin-angiotensin-aldosterone system; and lipid management.Kidney International advance online publication, 30 April 2014; doi:10.1038/ki.2014.128.
    Kidney International 04/2014; · 8.52 Impact Factor
  • Bertram L Kasiske, David C Wheeler
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    ABSTRACT: Kidney Disease: Improving Global Outcomes (KDIGO) was founded in 2003 to fulfill a need for international cooperation and consolidation in the development and implementation of clinical practice guidelines. KDIGO has experienced a rapid growth in the development of guidelines, producing three guidelines in its first 6 years and another six in the last 3 years. In addition, it has held 12 global conferences on important issues in kidney disease and its treatment. A major effort is under way to support the dissemination and implementation of KDIGO guidelines through various channels, including an Implementation Task Force with official representatives in 86 countries. KDIGO is now under its own management and remains committed to the development of evidence-based guidelines. Future challenges include finding adequate sources of funding and building stronger links with other organizations involved in guideline development and implementation.
    Nephrology Dialysis Transplantation 11/2013; · 3.37 Impact Factor
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    ABSTRACT: The risk of cardiovascular disease is increased by up to 33 to 50× in chronic inflammatory states and convention doses of statins may not provide the same cardiovascular protection as in noninflamed patients. This study investigated whether the increase in 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCoA-R)-mediated cholesterol synthesis observed under inflammatory stress was resistant to the action of statins and if so, whether this was because of interference with the sterol regulatory element binding protein cleavage-activating protein pathway. Inflammatory stress was induced by adding cytokines (interleukin-1β, tumor necrosis factor-α, and interleukin-6) and lipopolysaccharides to vascular smooth muscle cells in vitro and by subcutaneous casein injection in apolipoprotein E/scavenger receptors class A/CD36 triple knockout mice in vivo. Inflammatory stress exacerbated cholesterol ester accumulation and was accompanied in vitro and in vivo by increased HMGCoA-R mRNA and protein expression mediated via activation of the sterol regulatory element binding protein cleavage-activating protein/sterol regulatory element binding protein-2 pathway. Atorvastatin reduced HMGCoA-R enzymatic activity and intracellular cholesterol synthesis in vitro. However, inflammatory stress weakened these suppressive effects. Atorvastatin at concentrations of 16 μmol/L inhibited HMGCoA-R activity by 50% in vascular smooth muscle cells, but the same concentration resulted in only 30% of HMGCoA-R activity in vascular smooth muscle cells in the presence of interleukin-1β. Knocking down sterol regulatory element binding protein cleavage-activating protein prevented statin resistance induced by interleukin-1β, and overexpression of sterol regulatory element binding protein cleavage-activating protein induced statin resistance even without inflammatory stress. In vivo, the amount of atorvastatin required to lower serum cholesterol and decrease aortic lipid accumulation rose from 2 to 10 mg/kg per day in the presence of inflammatory stress. Increased cholesterol synthesis mediated by HMGCoA-R under inflammatory stress may be one of the mechanisms for intracellular lipid accumulation and statin resistance.
    Arteriosclerosis Thrombosis and Vascular Biology 11/2013; · 6.34 Impact Factor
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    ABSTRACT: Context:The clinical course of secondary hyperparathyroidism (sHPT) in patients on hemodialysis is not well described, and the effect of the calcimimetic cinacalcet on disease progression is uncertain.Objective:To describe (a) the clinical course of sHPT in patients treated with phosphate binders and/or vitamin D sterols and (b) the impact of cinacalcet on occurrence of severe unremitting HPT, defined by the persistence of markedly elevated parathyroid hormone (PTH) concentrations together with hypercalcemia or parathyroidectomy (PTX).Design:Randomized, double-blind, placebo-controlled clinical trial.Setting:Global, multicenter.Patients:3883 patients on hemodialysis of 5755 screened with moderate to severe sHPT.Main outcome measures:Parathyroidectomy, severe, unremitting HPT and use of commercial cinacalcet (a protocol violation).Intervention:Cinacalcet (30 to 180 mg daily) or placebo for up to 64 months.Results:In the 1935 patients randomized to placebo, 278 (14%) patients underwent PTX (median PTH 1872 pg/mL within prior 12 weeks of surgery). Age, sex, geographic region, co-morbidity, calcium-containing phosphate binder use, and baseline serum calcium, phosphorus and PTH concentrations were associated with PTX. Commercial cinacalcet was started in 443 (23%) patients (median PTH 1108 pg/mL before treatment began). Severe unremitting HPT developed in 470 (24%) patients. In a multivariable Cox model, the relative hazard (comparing patients randomized to cinacalcet versus placebo) of severe unremitting HPT was 0.31 (95% CI 0.26 to 0.37). The relative hazard differed little when adjusted by baseline clinical characteristics.Conclusions:Severe unremitting HPT develops frequently in patients on hemodialysis despite conventional therapy, and cinacalcet substantially reduces its occurrence.
    The Journal of Clinical Endocrinology and Metabolism 10/2013; · 6.31 Impact Factor
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    ABSTRACT: The amount of irreversible injury on renal allograft biopsy predicts function, but little is known about the early evolution of this damage. In a single-center cohort, we examined the relationship between donor-, recipient-, and transplantation-associated factors and change in a morphometric index of chronic damage (ICD) between protocol biopsies performed at implantation and at 2-3 months. We then investigated whether early delta ICD predicted subsequent biochemical outcomes. We found little evidence to support differences between the study group, who had undergone serial biopsies, and a contemporaneous control group, who had not. In allografts with serial biopsies (n = 162), there was an increase in ICD between implantation (median: 2%, IQR:0-8) and 2-3 months post-transplant (median 8% IQR:4-15; p < 0.0001). Donation from younger or live donors was independently associated with smaller early post-transplant increases in ICD. There was no evidence for a difference in delta ICD between donation after cardiac death vs. donation after brain death, nor association with length of cold ischemia. After adjustment for GFR at the time of the second biopsy, delta ICD after three months did not predict allograft function at one yr. These findings suggest that graft damage develops shortly after transplantation and reflects donor factors, but does not predict future biochemical outcomes.
    Clinical Transplantation 10/2013; · 1.49 Impact Factor
  • Richard Haynes, David C Wheeler
    Nature Reviews Nephrology 07/2013; · 7.94 Impact Factor
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    ABSTRACT: Chronic kidney disease (CKD)-mineral and bone disorder is associated with diverse metabolic and endocrine disturbances that ultimately may contribute to further loss of kidney function, bone demineralization, and fatal or nonfatal cardiovascular events. Recent insights into the pathophysiology of the events that unfold during the development of this disorder suggest that disturbances in phosphate metabolism are pivotal. The consequences of abnormal phosphate homeostasis are evident at estimated glomerular filtration rates <70 mL/min/1.73 m(2), long before serum phosphate levels increase. Healthy individuals with blood phosphate levels in the top quartile of the normal range have an increased risk of developing CKD, reaching end-stage renal disease, and experiencing cardiovascular events. Substantial public health consequences may be related to increased dietary phosphorus exposure from additives that contain phosphate in the food supply and from modest increases in serum phosphate levels; however, it remains to be established whether interventions aimed at these targets can impact on the development of adverse clinical outcomes. Current approaches involving dietary intervention and intestinal phosphate binders are based on principles and assumptions that need to be examined more rigorously. Compelling animal, observational, and clinical data indicate that interventions directed at lowering phosphate exposure and serum phosphate levels should be subject to rigorous clinical trials that use appropriate placebo comparators and focus on key clinical outcomes, such as cardiovascular events, progression of CKD, fractures, quality of life, and mortality.
    American Journal of Kidney Diseases 06/2013; · 5.76 Impact Factor
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    ABSTRACT: BACKGROUND: Arterial calcification (AC) is a major health problem associated with extreme morbidity and a shortened survival. It is currently without any effective treatment. ATP and the purinergic system in general are now emerging as being important in the pathogenesis of AC and potentially provide a new focus for novel therapies. METHODS: This review systematically analyses and discusses the current literature examining the relevance of the purinergic system to AC. Particular emphasis is given to the enzymes associated with ATP metabolism and their role in maintaining a balance between promotion and inhibition of arterial mineralization. Points of controversy are highlighted, and areas for future research are suggested. CONCLUSION: The potential roles of ATP and the purinergic system in AC are beginning to be elucidated. While further work is necessary, current knowledge suggests that several components of the purinergic system could be targeted to develop new treatments for AC.
    European Journal of Clinical Investigation 01/2013; · 3.37 Impact Factor
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    ABSTRACT: Mortality in patients with end-stage renal disease (ESRD) remains unacceptably high. Emerging techniques and advances in dialysis technology have the potential to improve clinical outcomes in the ESRD population. This report summarizes the deliberations and recommendations of a conference sponsored by Kidney Disease: Improving Global Outcomes to address the following questions: (1) what is the appropriate frequency and duration of hemodialysis; (2) how should we optimize water quality and dialysate composition; and (3) what technical innovations in blood purification and bioengineering can result in better clinical outcomes? The conference report will augment our current understanding of clinical practice in blood purification and will pose several high-priority research questions.Kidney International advance online publication, 16 January 2013; doi:10.1038/ki.2012.450.
    Kidney International 01/2013; · 8.52 Impact Factor
  • Bertram L Kasiske, David C Wheeler
    American Journal of Kidney Diseases 12/2012; · 5.76 Impact Factor
  • New England Journal of Medicine 11/2012; · 54.42 Impact Factor
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    ABSTRACT: OBJECTIVE: Asymmetric dimethylarginine is an endogenous inhibitor of NO synthesis that may mediate cardiovascular disease. Alanine-glyoxylate aminotransferase-2 (AGXT2) has been proposed to degrade asymmetric dimethylarginine. We investigated the significance of AGXT2 in methylarginine metabolism in vivo and examined the effect of this enzyme on blood pressure. METHODS AND RESULTS: In isolated mouse kidney mitochondria, we show asymmetric dimethylarginine deamination under physiological conditions. We demonstrate increased asymmetric dimethylarginine, reduced NO, and hypertension in an AGXT2 knockout mouse. We provide evidence for a role of AGXT2 in methylarginine metabolism in humans by demonstrating an inverse relationship between renal (allograft) gene expression and circulating substrate levels and an association between expression and urinary concentrations of the product. Finally, we examined data from a meta-analysis of blood pressure genome-wide association studies. No genome-wide significance was observed, but taking a hypothesis-driven approach, there was a suggestive association between the T allele at rs37369 (which causes a valine-isoleucine substitution and altered levels of AGXT2 substrate) and a modest increase in diastolic blood pressure (P=0.0052). CONCLUSIONS: Although the effect of variation at rs37369 needs further study, these findings suggest that AGXT2 is an important regulator of methylarginines and represents a novel mechanism through which the kidney regulates blood pressure.
    Arteriosclerosis Thrombosis and Vascular Biology 09/2012; · 6.34 Impact Factor
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    ABSTRACT: Some propose using phosphate binders in the CKD population given the association between higher levels of phosphorus and mortality, but their safety and efficacy in this population are not well understood. Here, we aimed to determine the effects of phosphate binders on parameters of mineral metabolism and vascular calcification among patients with moderate to advanced CKD. We randomly assigned 148 patients with estimated GFR=20-45 ml/min per 1.73 m(2) to calcium acetate, lanthanum carbonate, sevelamer carbonate, or placebo. The primary endpoint was change in mean serum phosphorus from baseline to the average of months 3, 6, and 9. Serum phosphorus decreased from a baseline mean of 4.2 mg/dl in both active and placebo arms to 3.9 mg/dl with active therapy and 4.1 mg/dl with placebo (P=0.03). Phosphate binders, but not placebo, decreased mean 24-hour urine phosphorus by 22%. Median serum intact parathyroid hormone remained stable with active therapy and increased with placebo (P=0.002). Active therapy did not significantly affect plasma C-terminal fibroblast growth factor 23 levels. Active therapy did, however, significantly increase calcification of the coronary arteries and abdominal aorta (coronary: median increases of 18.1% versus 0.6%, P=0.05; abdominal aorta: median increases of 15.4% versus 3.4%, P=0.03). In conclusion, phosphate binders significantly lower serum and urinary phosphorus and attenuate progression of secondary hyperparathyroidism among patients with CKD who have normal or near-normal levels of serum phosphorus; however, they also promote the progression of vascular calcification. The safety and efficacy of phosphate binders in CKD remain uncertain.
    Journal of the American Society of Nephrology 07/2012; 23(8):1407-15. · 9.47 Impact Factor
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    ABSTRACT: Secondary hyperparathyroidism (sHPT) and other abnormalities associated with chronic kidney disease-mineral bone disorder can contribute to dystrophic (including vascular) calcification. Dietary modification and variety of medications can be used to attenuate the severity of sHPT. However, it is unknown whether any of these approaches can reduce the high risks of death and cardiovascular disease in patients with end-stage renal disease. The Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events (EVOLVE) trial was designed to test the hypothesis that treatment with the calcimimetic agent cinacalcet compared with placebo (on a background of conventional therapy including phosphate binders +/- vitamin D sterols) reduces time to death or non-fatal cardiovascular events (specifically myocardial infarction, unstable angina, heart failure and peripheral arterial disease events) among patients on hemodialysis with sHPT. This report describes baseline characteristics of enrolled subjects with a focus on regional variation. There were 3883 subjects randomized from 22 countries, including the USA, Canada, Australia, three Latin American nations, Russia and 15 European nations. The burden of overt cardiovascular disease at baseline was high (e.g. myocardial infarction 12.4%, heart failure 23.3%). The median plasma parathyroid hormone concentration at baseline was 692 pg/mL (10%, 90% range, 363-1694 pg/mL). At baseline, 87.2% of subjects were prescribed phosphate binders and 57.5% were prescribed activated vitamin D derivatives. Demographic data, comorbid conditions and baseline laboratory data varied significantly across regions. EVOLVE enrolled 3883 subjects on hemodialysis with moderate to severe sHPT. Inclusion of subjects from multiple global regions with varying degrees of disease severity will enhance the external validity of the trial results.
    Nephrology Dialysis Transplantation 04/2012; 27(7):2872-9. · 3.37 Impact Factor
  • David C Wheeler, Ben Caplin
    Journal of the American Society of Nephrology 04/2012; 23(5):770-3. · 9.47 Impact Factor

Publication Stats

3k Citations
644.08 Total Impact Points


  • 2001–2014
    • University College London
      • Centre for Nephrology
      Londinium, England, United Kingdom
  • 2012–2013
    • Hennepin County Medical Center
      Minneapolis, Minnesota, United States
    • London School of Hygiene and Tropical Medicine
      • Faculty of Epidemiology and Population Health
      Londinium, England, United Kingdom
  • 2006–2013
    • University of Oxford
      • Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU)
      Oxford, ENG, United Kingdom
  • 2010
    • RWTH Aachen University
      Aachen, North Rhine-Westphalia, Germany
  • 2007
    • Universitair Ziekenhuis Ghent
      Gand, Flanders, Belgium
  • 2003
    • University Hospitals Birmingham NHS Foundation Trust
      • Department of Nephrology
      Birmingham, ENG, United Kingdom
  • 2000–2001
    • Queen Elizabeth Hospital Birmingham
      Birmingham, England, United Kingdom
    • University of Wales
      • College of Medicine
      Cardiff, Wales, United Kingdom
  • 1999–2001
    • University of Birmingham
      • Group of Medical Science and Education
      Birmingham, ENG, United Kingdom
    • The Queen Elizabeth Hospital
      Tarndarnya, South Australia, Australia
  • 1994
    • Beverly Hospital, Boston MA
      Beverly, Massachusetts, United States