James S Kaufman

CUNY Graduate Center, New York, New York, United States

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Publications (71)537.33 Total impact

  • Mae Thamer · James S Kaufman · Yi Zhang · Qian Zhang · Dennis J Cotter · Heejung Bang
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    ABSTRACT: A shared decision-making tool could help elderly patients with advanced chronic kidney disease decide about initiating dialysis therapy. Because mortality may be high in the first few months after initiating dialysis therapy, incorporating early mortality predictors in such a tool would be important for an informed decision. Our objective is to derive and validate a predictive risk score for early mortality after initiating dialysis therapy. Retrospective observational cohort, with development and validation cohorts. US Renal Data System and claims data from the Centers for Medicare & Medicaid Services for 69,441 (aged ≥67 years) patients with end-stage renal disease with a previous 2-year Medicare history who initiated dialysis therapy from January 1, 2009, to December 31, 2010. Demographics, predialysis care, laboratory data, functional limitations, and medical history. All-cause mortality in the first 3 and 6 months. Predicted mortality by logistic regression. The simple risk score (total score, 0-9) included age (0-3 points), low albumin level, assistance with daily living, nursing home residence, cancer, heart failure, and hospitalization (1 point each), and showed area under the receiver operating characteristic curve (AUROC)=0.69 in the validation sample. A comprehensive risk score with additional predictors was also developed (with AUROC=0.72, high concordance between predicted vs observed risk). Mortality probabilities were estimated from these models, with the median score of 3 indicating 12% risk in 3 months and 20% in 6 months, and the highest scores (≥8) indicating 39% risk in 3 months and 55% in 6 months. Patients who did not choose dialysis therapy and did not have a 2-year Medicare history were excluded. Routinely available information can be used by patients with chronic kidney disease, families, and their nephrologists to estimate the risk of early mortality after dialysis therapy initiation, which may facilitate informed decision making regarding treatment options. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
    American Journal of Kidney Diseases 06/2015; DOI:10.1053/j.ajkd.2015.05.014 · 5.76 Impact Factor
  • Journal of Vascular Surgery 06/2015; 61(6):109S-110S. DOI:10.1016/j.jvs.2015.04.213 · 2.98 Impact Factor
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    ABSTRACT: Background: There is an epidemic of chronic kidney disease (CKD) of unknown etiology in Central American workers. Objectives: To investigate changes and job-specific differences in kidney function over a 6-month sugarcane harvest season, explore the potential role of hydration, and measure proteinuria. Methods: We recruited 284 Nicaraguan sugarcane workers performing seven distinct tasks. We measured urine albumin and serum creatinine and estimated glomerular filtration rate (eGFR). Results: eGFR varied by job and decreased during the harvest in seed cutters (-8·6 ml/min/1·73 m(2)), irrigators (-7·4 ml/min/1·73 m(2)), and cane cutters (-5·0 ml/min/1·73 m(2)), as compared to factory workers. The number of years employed at the company was negatively associated with eGFR. Fewer than 5% of workers had albumin-to-creatinine ratio (ACR) >30 mg/g. Conclusions: The decline in kidney function during the harvest and the differences by job category and employment duration provide evidence that one or more risk factors of CKD are occupational.
    International journal of occupational and environmental health 01/2015; DOI:10.1179/2049396714Y.0000000102 · 1.10 Impact Factor
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    ABSTRACT: Background: Epoetin therapy used to treat anemia among ESRD patients has cost Medicare ∼$40 billion. Since January 2011, epoetin has been reimbursed via a new bundled prospective payment system (PPS). Our aim was to determine changes in epoetin dosing and hematocrit levels in response to PPS by different types of dialysis providers. Methods: Data from the USRDS were used to identify 187,591 and 206,163 Medicare-eligible ESRD patients receiving hemodialysis during January 2010 (pre-PPS) and December 2011 (post-PPS). Standardized weekly mean epoetin dose administered pre- and post-PPS and adjustment in dose (titration) based on previous hematocrit level in each facility was disaggregated by profit status, chain membership and size. Results: Major declines in epoetin use, dosing and achieved hematocrit levels were observed after PPS. Among the three largest dialysis chains, the decline in standardized epoetin dose was 29% at Fresenius, 47% at DaVita, and 52% at DCI. The standardized weekly epoetin dose among profit and nonprofit facilities declined by 38 and 42%, respectively. Changes in titration patterns suggest that a new hematocrit target of 30-33% was in place after PPS, replacing the erstwhile 33-36% hematocrit target used before PPS. Conclusion: Historically, important differences in anemia management were evident by dialysis organizational status. However, the confluence of financial incentives bundling epoetin payments and mounting scientific evidence linking higher hematocrit targets and higher epoetin doses to adverse outcomes have culminated in lower access to epoetin and lower doses across all dialysis providers in the first year after PPS. © 2015 S. Karger AG, Basel.
    American Journal of Nephrology 01/2015; 40(6):554-560. DOI:10.1159/000370334 · 2.65 Impact Factor
  • Journal of Vascular Surgery 09/2014; 60(3):832. DOI:10.1016/j.jvs.2014.06.077 · 2.98 Impact Factor
  • Mae Thamer · Yi Zhang · Onkar Kshirsagar · Dennis J Cotter · James S Kaufman
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    ABSTRACT: In a landmark study, TREAT (Trial to Reduce Cardiovascular Events With Aranesp Therapy) examined the use of erythropoiesis-stimulating agent (ESA) therapy to treat anemia among patients with chronic kidney disease (CKD) and found no benefit compared to placebo.
    American Journal of Kidney Diseases 07/2014; 64(5). DOI:10.1053/j.ajkd.2014.05.013 · 5.76 Impact Factor
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    ABSTRACT: Randomized trials found that use of erythropoiesis-stimulating agents to target normal hematocrit (Hct) levels (>39%) compared with 27%-34.5% increases cardiovascular risk and mortality among chronic kidney disease patients. However, the effects of the most widely used Hct target in the past 2 decades, 34.5%-39%, have never been examined. To compare the effects of 2 Hct target strategies-30.0%-34.5% (low) and 34.5%-39.0% (mid) in a high-risk population: elderly dialysis patients with significant comorbidities. Observational data from the US Renal Data System were used to emulate a randomized trial in which patients were assigned to either Hct strategy. Follow-up started after completing 3 months of hemodialysis and ended 6 months later. We conducted the observational analogs of intention-to-treat and per-protocol analyses. Inverse-probability weighting was used to adjust for measured time-dependent confounding by indication. A total of 22,474 elderly patients with both diabetes and cardiovascular disease who initiated hemodialysis in 2006-2008. Hazard ratios (HRs) and survival probabilities for all-cause mortality and a composite cardiovascular and mortality endpoint. The intention-to-treat HR (95% confidence interval) for mid versus low Hct strategy was 1.05 (0.99-1.11) for all-cause mortality and 1.03 (0.98-1.08) for the composite endpoint. The per-protocol HR (95% confidence interval) for mid versus low Hct strategy was 0.98 (0.78-1.24) for all-cause mortality and 1.00 (0.81-1.24) for the composite outcome. Among hemodialysis patients, we did not find differences in 6-month survival or cardiovascular risk between clinical strategies that target Hct at 30.0%-34.5% versus 34.5%-39.0%.
    Medical care 03/2014; 52 Suppl 3:S132-9. DOI:10.1097/MLR.0b013e3182a53ca8 · 2.94 Impact Factor
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    ABSTRACT: Aims: The concentration of fibroblast growth factor 23 (FGF-23) is elevated in patients on dialysis. FGF receptors have been implicated in the pathogenesis of left ventricular (LV) hypertrophy. The objective of this study was to examine the associations between high plasma FGF-23 concentration and LV systolic dysfunction. Methods: We tested the hypothesis that high plasma FGF-23 concentration is associated with LV dysfunction in 110 chronic dialysis patients from the Homocysteine study who had paired echocardiograms performed for clinical indications. C-terminal FGF-23 concentrations were measured in stored plasma samples. Multivariate regression analyses were performed to evaluate the association of FGF-23 concentration with LV dysfunction. Results: Participants had a mean age of 60 ± 11 years. Median FGF-23 level and mean ejection fraction (EF) at baseline were 4,632 (1,384 - 14,997) RU/ml and 50 ± 13%, respectively. Median follow-up time was 1.9 years. Higher FGF-23 concentration was directly associated with decreases in EF during follow-up. After adjustment for demographics, baseline EF, hypertension, diabetes, cardiovascular disease, body mass index, systolic blood pressure, hemoglobin and markers of mineral metabolism, participants with FGF-23 in the highest tertile had an 8% decrease in EF compared to participants in the lowest tertile (β -8.0, 95% CI -15.5 to -0.53; p = 0.04). When FGF-23 was evaluated as a continuous variable, for every log10 increase in FGF-23, EF decreased during follow-up by 6.5% (β -6.5, 95% CI -11.3 to -1.73; p = 0.01). Conclusion: In conclusion, higher FGF-23 concentration is independently associated with LV systolic dysfunction in chronic dialysis patients.
    Clinical nephrology 07/2013; 80(5). DOI:10.5414/CN107991 · 1.23 Impact Factor
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    ABSTRACT: Contrast-induced AKI (CI-AKI) is a common condition associated with serious, adverse outcomes. CI-AKI may be preventable because its risk factors are well characterized and the timing of renal insult is commonly known in advance. Intravenous (IV) fluids and N-acetylcysteine (NAC) are two of the most widely studied preventive measures for CI-AKI. Despite a multitude of clinical trials and meta-analyses, the most effective type of IV fluid (sodium bicarbonate versus sodium chloride) and the benefit of NAC remain unclear. Careful review of published trials of these interventions reveals design limitations that contributed to their inconclusive findings. Such design limitations include the enrollment of small numbers of patients, increasing the risk for type I and type II statistical errors; the use of surrogate primary endpoints defined by small increments in serum creatinine, which are associated with, but not necessarily causally related to serious, adverse, patient-centered outcomes; and the inclusion of low-risk patients with intact baseline kidney function, yielding low event rates and reduced generalizability to a higher-risk population. The Prevention of Serious Adverse Events following Angiography (PRESERVE) trial is a randomized, double-blind, multicenter trial that will enroll 8680 high-risk patients undergoing coronary or noncoronary angiography to compare the effectiveness of IV isotonic sodium bicarbonate versus IV isotonic sodium chloride and oral NAC versus oral placebo for the prevention of serious, adverse outcomes associated with CI-AKI. This article discusses key methodological issues of past trials investigating IV fluids and NAC and how they informed the design of the PRESERVE trial.
    Clinical Journal of the American Society of Nephrology 05/2013; 8. DOI:10.2215/CJN.11161012 · 5.25 Impact Factor
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    ABSTRACT: Background Northwestern Nicaragua has a high prevalence of chronic kidney disease (CKD) of unknown cause among young adult men. In addition, frequent occurrence of urinary tract infections (UTI) among men and a dysuria syndrome described by sugarcane workers as “chistata” are both reported. This study examines health professionals´ perceptions regarding etiology of these conditions and their treatment approaches, including use of potentially nephrotoxic medications. Methods Nineteen in-person semi-structured interviews were conducted in November 2010 among ten physicians and nine pharmacists practicing in the region. Results Health professionals perceived CKD as a serious and increasing problem in the region, primarily affecting young men working as manual laborers. All interviewees regarded occupational and environmental exposure to sun and heat, and dehydration as critical factors associated with the occurrence of CKD. These factors were also considered to play a role in the occurrence of chistata in the region. Health professionals indicated that reluctance among workers to hydrate might be influenced by perceptions of water contamination. Symptoms often were treated with non-steroidal anti-inflammatory drugs (NSAIDs), diuretics and antibiotics. Physicians acknowledged that the diagnosis of UTI usually was not based on microbial culture and opined that the use of potentially nephrotoxic medications may be contributing to CKD. Conclusions Interviews provided evidence suggesting that medications such as diuretics, antibiotics and NSAIDs are widely used and sold over the counter for symptoms that may be related to dehydration and volume depletion. These factors, alone or in combination, may be possible contributors to kidney damage. Acute kidney damage coupled with volume depletion and exposures including medications and infectious agents should be further evaluated as causal factors for CKD in this region.
    BMC Public Health 04/2013; 13(1):350. DOI:10.1186/1471-2458-13-350 · 2.32 Impact Factor
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    ABSTRACT: Background: Fibroblast growth factor 23 (FGF23) has been associated with death in dialysis patients. Since FGF23 shares structural features with FGF19 subfamily members that exert hormonal control of fat mass, we hypothesized that high circulating FGF23 concentrations would be associated with the development of a uremic lipid profile and lower body mass index (BMI). Methods: This study was conducted among 654 patients receiving chronic hemodialysis. C-terminal FGF23 concentrations were measured in stored plasma samples. Linear regression was used to examine the cross-sectional associations of plasma FGF23 concentrations with BMI, total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides. Cox proportional hazard models were used to examine the association between FGF23 concentrations and all-cause mortality. Results: Participants had a mean age of 60 ± 11 years and a median (IQR) FGF23 concentration of 4,212 (1,411-13,816) RU/ml. An increase per SD in log(10) FGF23 was associated with lower BMI (β = -1.11; p = 0.008), TC (β = -6.46; p = 0.02), LDL-C (β = -4.73; p = 0.04) and HDL-C (β = -2.14; p = 0.03); after adjusting for age, gender, race, cardiovascular risk factors, serum albumin, markers of mineral metabolism, and use of lipid-lowering drugs. The association of FGF23 with death was attenuated after adjustment for HDL-C (HR of highest quartile 1.53, 95% CI 1.06-2.20 compared to lowest quartile). Conclusion: These results indicate that higher plasma FGF23 levels are associated with lower BMI and dyslipidemia in dialysis patients. The association between FGF23 and death may be mediated through unexplored metabolic risk factors unrelated to mineral metabolism.
    American Journal of Nephrology 02/2013; 37(3):183-190. DOI:10.1159/000346941 · 2.65 Impact Factor
  • James S Kaufman
    American Journal of Kidney Diseases 02/2013; 61(2):191-3. DOI:10.1053/j.ajkd.2012.12.001 · 5.76 Impact Factor
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    ABSTRACT: Recent reports have described an apparent epidemic of CKD along the Pacific coast of Central America, such that CKD is a leading cause of death among working-age men in lower-altitude agricultural communities in this region. Given the limited availability of kidney replacement therapies in this region, CKD often is a terminal diagnosis, lending greater urgency to the identification of a modifiable cause. This article discusses the epidemiology of CKD in this region, reviews the clinical features of this CKD outbreak, discusses potential causes and the evidence supporting these hypotheses, and highlights the wider implications of this epidemic of CKD.
    Clinical Journal of the American Society of Nephrology 10/2012; 8(3). DOI:10.2215/CJN.05050512 · 5.25 Impact Factor
  • Z Rafeq · J D Roh · P Guarino · J Kaufman · J Joseph
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    ABSTRACT: BACKGROUND & AIMS: Hyperhomocysteinaemia (HHCY), a common finding in patients with chronic kidney disease (CKD), has been shown to contribute to adverse cardiac remodelling and failure. We hypothesised that in human subjects with CKD, HHCY would be associated with myocardial dysfunction, and that homocysteine (HCY)-lowering therapy would improve myocardial remodelling and heart-failure (HF) outcomes. METHODS AND RESULTS: Post hoc analysis of the Homocysteinemia in Kidney and End Stage Renal Disease (HOST) trial (n=2056) was performed to determine if HCY-lowering therapy with high dose B vitamins affects HF outcomes in patients with CKD. In addition, effects on myocardial remodelling were assessed in a subgroup of 220 trial subjects who had transthoracic echocardiograms done before study randomisation and during the course of the study as part of their routine clinical care. HF outcomes were not significantly affected by treatment compared to the placebo. HCY levels were inversely correlated with diastolic function (R=-0.21; p=0.038). Vitamin therapy resulted in a significant increase in left atrial size (+0.15±0.8cm vs. -0.13±0.07cm; p=0.0095). No other echocardiographic parameters were significantly associated with baseline HCY levels or changes with vitamin therapy. CONCLUSION: HHCY is associated with diastolic dysfunction in patients with CKD. However, B-vitamin therapy did not improve HF outcomes despite lowering of plasma HCY levels, and was associated with an increase in left atrial size, which is a surrogate for worsening left ventricular diastolic dysfunction. These findings suggest that high-dose B vitamin therapy may be harmful in patients with CKD.
    Nutrition, metabolism, and cardiovascular diseases: NMCD 08/2012; 23(9). DOI:10.1016/j.numecd.2012.07.002 · 3.88 Impact Factor
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    ABSTRACT: Background: Patients with chronic kidney disease (CKD) not requiring dialysis have a high prevalence of 25-hydroxyvitamin D (25(OH)D) deficiency but the relationship between 25(OH)D levels and metabolic syndrome is unknown in this population. Methods: This study analyzed stored plasma samples from 495 non-diabetic subjects with severe kidney disease, not yet on dialysis, who participated in the homocysteine in kidney and end stage renal disease study. Metabolic syndrome was defined as the presence of all three of the following: (1) Serum triglycerides ≥ 150 mg/dl or drug treatment for hypertriglyceridemia; (2) serum high density lipoprotein-cholesterol (HDL-C) < 50 mg/dl for women or < 40 mg/dl for men or drug treatment for dyslipidemia; and (3) blood pressure ≥ 130/85 mmHg or drug treatment for hypertension. Multivariate logistic regression models were used to evaluate the cross-sectional association between plasma 25(OH)D levels and metabolic syndrome. Results: The prevalence of metabolic syndrome increased as 25(OH)D levels declined, with the highest prevalence in participants with 25(OH)D levels < 20 ng/ml. Participants with 25(OH)D levels < 20 ng/ml had a significantly increased risk of metabolic syndrome compared to subjects with levels > 30 ng/ml after adjustment for multiple confounders (OR 2.25, 95% CI 1.25 - 4.07). Plasma 25(OH)D levels were inversely associated with diastolic blood pressure (R = -0.10, p = 0.029) and serum triglyceride levels (R = -0.14, p = 0.002). Conclusion: 25(OH)D deficiency is strongly associated with an increased risk of metabolic syndrome in non-diabetic patients with severe CKD not yet on dialysis, independent of cardiometabolic risk factors and other important regulators of mineral metabolism.
    Clinical nephrology 07/2012; 78(6). DOI:10.5414/CN107498 · 1.23 Impact Factor
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    ABSTRACT: Low vitamin D concentrations are prevalent in patients with chronic kidney disease (CKD). We investigated the relationship between plasma 25-hydroxyvitamin D (25[OH]D) or 1,25-dihydroxyvitamin D (1,25[OH](2)D) concentrations with death, cardiovascular events, and dialysis therapy initiation in patients with advanced CKD. The HOST (Homocysteinemia in Kidney and End Stage Renal Disease) Study was a randomized double-blind trial evaluating the effects of high doses of folic acid on death and long-term dialysis therapy initiation in patients with advanced CKD (stages 4 and 5 not yet on dialysis therapy). 25(OH)D and 1,25(OH)(2)D were measured in stored plasma samples obtained 3 months after trial initiation and evaluated at clinically defined cutoffs (<10, 10-30, and >30 ng/mL) and tertiles (<15, 15-22, and >22 pg/mL), respectively. Cox proportional hazard models were used to examine the association between vitamin D concentrations and clinical outcomes. 1,099 patients with advanced CKD from 36 Veteran Affairs Medical Centers. 25(OH)D and 1,25(OH)(2)D concentrations. Death, cardiovascular events, and time to initiation of long-term dialysis therapy. After a median follow-up of 2.9 years, 41% (n = 453) died, whereas 56% (n = 615) initiated dialysis therapy. Mean 25(OH)D and 1,25(OH)(2)D concentrations were 21 ± 10 ng/mL and 20 ± 11 pg/mL, respectively. After adjustment for potential confounders, the lowest tertile of 1,25(OH)(2)D was associated with death (HR, 1.33; 95% CI, 1.01-1.74) and initiation of long-term dialysis therapy (HR, 1.78; 95% CI, 1.40-2.26) compared with the highest tertile. The association with death and initiation of dialysis therapy was moderately attenuated after adjustment for plasma fibroblast growth factor 23 (FGF-23) concentrations (HRs of lower tertiles of 1.20 [95% CI, 0.91-1.58] and 1.56 [95% CI, 1.23-1.99], respectively, compared with highest tertile). There was no association between 25(OH)D concentrations and outcomes. Participants were mostly men. Low plasma 1,25(OH)(2)D concentrations are associated with death and initiation of long-term dialysis therapy in patients with advanced CKD. FGF-23 level may attentuate this relationship.
    American Journal of Kidney Diseases 05/2012; 60(4):567-75. DOI:10.1053/j.ajkd.2012.04.014 · 5.76 Impact Factor
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    ABSTRACT: AKI remains an important clinical problem, with a high mortality rate, increasing incidence, and no Food and Drug Administration-approved therapeutics. Advances in addressing this clinical need require approaches for rapid diagnosis and stratification of injury, development of therapeutic agents based on precise understanding of key pathophysiological events, and implementation of well designed clinical trials. In the near future, AKI biomarkers may facilitate trial design. To address these issues, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a meeting, "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers," in December of 2010 that brought together academic investigators, industry partners, and representatives from the National Institutes of Health and the Food and Drug Administration. Important issues in the design of clinical trials for interventions in AKI in patients with sepsis or AKI in the setting of critical illness after surgery or trauma were discussed. The sepsis working group discussed use of severity of illness scores and focus on patients with specific etiologies to enhance homogeneity of trial participants. The group also discussed endpoints congruent with those endpoints used in critical care studies. The second workgroup emphasized difficulties in obtaining consent before admission and collaboration among interdisciplinary healthcare groups. Despite the difficult trial design issues, these clinical situations represent a clinical opportunity because of the high event rates, severity of AKI, and poor outcomes. The groups considered trial design issues and discussed advantages and disadvantages of several short- and long-term primary endpoints in these patients.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):856-60. DOI:10.2215/CJN.12821211 · 5.25 Impact Factor
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    ABSTRACT: AKI is an important clinical problem that has become increasingly more common. Mortality rates associated with AKI remain high despite advances in supportive care. Patients surviving AKI have increased long-term mortality and appear to be at increased risk of developing CKD and progressing to ESRD. No proven effective pharmacologic therapies are currently available for the prevention or treatment of AKI. Advances in addressing this unmet need will require the development of novel therapeutic agents based on precise understanding of key pathophysiological events and the implementation of well designed clinical trials. To address this need, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored the "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" workshop in December 2010. The event brought together representatives from academia, industry, the National Institutes of Health, and the US Food and Drug Administration. We report the discussions of workgroups that developed outlines of clinical trials for the prevention of AKI in two patient populations: patients undergoing elective surgery who are at risk for or who develop AKI, and patients who are at risk for contrast-induced AKI. In both of these populations, primary prevention or secondary therapy can be delivered at an optimal time relative to kidney injury. The workgroups detailed primary and secondary endpoints for studies in these groups, and explored the use of adaptive clinical trial designs for trials of novel preventive strategies to improve outcomes of patients with AKI.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):851-5. DOI:10.2215/CJN.12811211 · 5.25 Impact Factor
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    ABSTRACT: Acute kidney injury (AKI) remains a complex clinical problem associated with significant short-term morbidity and mortality and lacking effective pharmacologic interventions. Patients with AKI experience longer-term risks for progressive chronic ESRD, which diminish patients' health-related quality of life and create a larger burden on the healthcare system. Although experimental models have yielded numerous promising agents, translation into clinical practice has been unsuccessful, possibly because of issues in clinical trial design, such as delayed drug administration, masking of therapeutic benefit by adverse events, and inadequate sample size. To address issues of clinical trial design, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a workshop titled "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" in December 2010. Workshop participants included representatives from academia, industry, and government agencies whose areas of expertise spanned basic science, clinical nephrology, critical care medicine, biostatistics, pharmacology, and drug development. This document summarizes the discussions of collaborative workgroups that addressed issues related to patient selection, study endpoints, the role of novel biomarkers, sample size and power calculations, and adverse events and pilot/feasibility studies in prevention and treatment of AKI. Companion articles outline the discussions of workgroups for model trials related to prevention or treatment of established AKI in different clinical settings, such as in patients with sepsis.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):844-50. DOI:10.2215/CJN.12791211 · 5.25 Impact Factor
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    ABSTRACT: This study examined differences in the concentration of markers of mineral metabolism across race in patients with advanced CKD not requiring dialysis and ESRD. Concentrations of 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)(2)D), intact parathyroid hormone (iPTH), and fibroblast growth factor 23 (FGF-23) were measured in stored plasma samples of 1497 patients with advanced CKD not yet on dialysis and ESRD who participated in the Homocysteine in Kidney and End Stage Renal Disease study. Linear regression models were used to examine the relationship between race and 25(OH)D, 1,25(OH)(2)D, iPTH, and FGF-23 concentrations. Non-Hispanic white patients comprised 58% of the cohort, whereas non-Hispanic blacks comprised 42%. Median (interquartile range) FGF-23 concentrations were lower in blacks compared with whites with CKD (323 [181-655] versus 431 [232-1026] RU/ml; P<0.001) but not in ESRD. In adjusted linear regression models, blacks with CKD not requiring dialysis had significantly lower plasma FGF-23 concentrations (difference, -159; 95% confidence interval, -205 to -106; P<0.001) compared with whites, independent of plasma 25(OH)D, 1,25(OH)(2)D, and iPTH concentrations. This difference was not observed in the ESRD group. The magnitude of correlation for the relationships between 1,25(OH)(2)D with iPTH, FGF-23 with 1,25(OH)(2)D, and FGF-23 with iPTH were stronger among blacks than whites with CKD not requiring dialysis. In advanced CKD not requiring dialysis, blacks have lower FGF-23 concentrations than whites. Blacks with CKD and ESRD have lower 25(OH)D and higher iPTH compared with whites, independent of FGF-23 concentrations.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(4):640-7. DOI:10.2215/CJN.07020711 · 5.25 Impact Factor

Publication Stats

2k Citations
537.33 Total Impact Points

Institutions

  • 2015
    • CUNY Graduate Center
      New York, New York, United States
  • 2014–2015
    • NYU Langone Medical Center
      New York, New York, United States
    • VA Long Beach Healthcare System
      Long Beach, California, United States
  • 2001–2013
    • Boston University
      • • Department of Medicine
      • • Renal Section
      Boston, Massachusetts, United States
    • U.S. Department of Veterans Affairs
      Washington, Washington, D.C., United States
  • 2012
    • Indiana University-Purdue University Indianapolis
      • Department of Medicine
      Indianapolis, IN, United States
  • 2010–2012
    • Beverly Hospital, Boston MA
      BVY, Massachusetts, United States
  • 2007–2010
    • University of Massachusetts Boston
      Boston, Massachusetts, United States
  • 2006–2009
    • Medical Technology and Practice Patterns Institute (MTPPI)
      Maryland, United States
  • 2005–2009
    • University of Iowa
      • Division of Nephrology
      Iowa City, Iowa, United States
    • The Ohio State University
      Columbus, Ohio, United States
  • 2004
    • Johns Hopkins University
      Baltimore, Maryland, United States