Chirag R Parikh

Yale-New Haven Hospital, New Haven, Connecticut, United States

Are you Chirag R Parikh?

Claim your profile

Publications (191)1157.35 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Acute kidney injury (AKI) after pediatric cardiac operations is associated with poor outcomes and is difficult to predict. We conducted a prospective study to evaluate whether preoperative brain natriuretic peptide (BNP) levels predict postoperative AKI among children undergoing cardiac operations. This was a three-center, prospective study (2007-2009) of 277 children undergoing cardiac operations (n = 121, aged <2 years) with available preoperative BNP values. Preoperative BNP was measured and categorized into tertiles. The performance of BNP was evaluated alone and in combination with clinical factors. AKI was defined as doubling of serum creatinine or need for acute dialysis. Postoperative AKI occurred in 165 children (60%), with 118 cases (43%) being mild and 47 cases (17%) severe. Preoperative BNP was not associated with increased risk of mild or severe postoperative AKI and did not significantly improve AKI risk prediction when added to clinical models. Preoperative BNP was, however, associated with several clinical outcomes, including length of stay and mechanical ventilation. The results were similar when the analysis was repeated in the subset of children younger than 2 years of age or when the association of postoperative BNP and AKI was evaluated. Preoperative BNP levels did not predict postoperative AKI in this cohort of children undergoing cardiac operations. Both preoperative and postoperative BNP levels are associated with postoperative outcomes. Clinical Trial Registration at Clinicaltrials.gov as NCT00774137.
    The Annals of thoracic surgery 04/2014; · 3.74 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Acute kidney injury (AKI) is a serious complication of cardiac operations for which there remains no specific therapy. Animal data and several observational studies suggest that statins prevent AKI, but the results are not conclusive, and many studies are retrospective in nature. We conducted a multicenter prospective cohort study of 625 adult patients undergoing elective cardiac operations. All patients were taking statins and were grouped according to whether statins were continued or held in the 24 hours before operation. The primary outcome was AKI as defined by a doubling of serum creatinine or dialysis. The secondary outcome was the peak level of several kidney injury biomarkers. The results were adjusted for demographic and clinical factors. Continuing (vs holding) a statin before operation was not associated with a lower risk of AKI, as defined by a doubling of serum creatinine or dialysis (adjusted relative risk [RR] 1.09; 95% confidence interval [CI] 0.44, 2.70). However, continuing a statin was associated with a lower risk of elevation of the following AKI biomarkers: urine interleukin-18, urine neutrophil gelatinase-associated lipocalin, urine kidney injury molecule-1, and plasma neutrophil gelatinase-associated lipocalin (adjusted RR 0.34; 95% CI 0.18, 0.62), (adjusted RR 0.41; 95% CI 0.22, 0.76), (adjusted RR 0.37; 95% CI 0.20, 0.76), (adjusted RR 0.62; 95% CI 0.39, 0.98), respectively. Statins may prevent kidney injury after cardiac operations, as evidenced by lower levels of kidney injury biomarkers.
    The Annals of thoracic surgery 04/2014; · 3.74 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Some studies but not others suggest angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) use prior to major surgery associates with a higher risk of postoperative acute kidney injury (AKI) and death. We conducted a large population-based retrospective cohort study of patients aged 66 years or older who received major elective surgery in 118 hospitals in Ontario, Canada from 1995 to 2010 (n = 237,208). We grouped the cohort into ACEi/ARB users (n = 101,494) and non-users (n = 135,714) according to whether the patient filled at least one prescription for an ACEi or ARB (or not) in the 120 days prior to surgery. Our study outcomes were acute kidney injury treated with dialysis (AKI-D) within 14 days of surgery and all-cause mortality within 90 days of surgery. After adjusting for potential confounders, preoperative ACEi/ARB use versus non-use was associated with 17% lower risk of post-operative AKI-D (adjusted relative risk (RR): 0.83; 95% confidence interval (CI): 0.71 to 0.98) and 9% lower risk of all-cause mortality (adjusted RR: 0.91; 95% CI: 0.87 to 0.95). Propensity score matched analyses provided similar results. The association between ACEi/ARB and AKI-D was significantly modified by the presence of preoperative chronic kidney disease (CKD) (P value for interaction < 0.001) with the observed association evident only in patients with CKD (CKD - adjusted RR: 0.62; 95% CI: 0.50 to 0.78 versus No CKD: adjusted RR: 1.00; 95% CI: 0.81 to 1.24). In this cohort study, preoperative ACEi/ARB use versus non-use was associated with a lower risk of AKI-D, and the association was primarily evident in patients with CKD. Large, multi-centre randomized trials are needed to inform optimal ACEi/ARB use in the peri-operative setting.
    BMC Nephrology 04/2014; 15(1):53. · 1.64 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Accurate and reliable assessment tools are needed in transplantation. The objective of this prospective, multi-center study was to determine the associations of the alpha and pi iso-enzymes of glutathione S-transferase (GST), measured from perfusate solution at the start and end (base and post) of kidney allograft machine perfusion, with subsequent delayed graft function (DGF). We also compared GST iso-enzyme perfusate levels from discarded versus transplanted kidneys. A total of 428 kidneys were linked to outcomes as recorded by the United Network of Organ Sharing. DGF, defined as any dialysis in the first week of transplant, occurred in 141 recipients (32%). Alpha- and pi-GST levels significantly increased during machine perfusion. The adjusted relative risks (95% confidence interval) of DGF with each log-unit increase in base and post pi-GST were 1.14 (1.0-1.3) and 1.36 (1.1-1.8), respectively. Alpha-GST was not independently associated with DGF. There were no significant differences in GST values between discarded and transplanted kidneys, though renal resistance was significantly higher in discarded kidneys. We found pi-GST at the end of machine perfusion to be independently associated with DGF. Further studies should elucidate the utility of GST for identifying injured kidneys with regard to organ allocation, discard and recipient management decisions.
    American Journal of Transplantation 02/2014; · 6.19 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: The influence of deceased-donor AKI on post-transplant outcomes is poorly understood. The few published studies about deceased-donor preimplant biopsy have reported conflicting results regarding associations between AKI and recipient outcomes. This multicenter study aimed to evaluate associations between deceased-donor biopsy reports of acute tubular necrosis (ATN) and delayed graft function (DGF), and secondarily for death-censored graft failure, first adjusting for the kidney donor risk index and then stratifying by donation after cardiac death (DCD) status. Between March 2010 and April 2012, 651 kidneys (369 donors, 4 organ procurement organizations) were biopsied and subsequently transplanted, with ATN reported in 110 (17%). There were 262 recipients (40%) who experienced DGF and 38 (6%) who experienced graft failure. DGF occurred in 45% of kidneys with reported ATN compared with 39% without ATN (P=0.31) resulting in a relative risk (RR) of 1.13 (95% confidence interval [95% CI], 0.9 to 1.43) and a kidney donor risk index-adjusted RR of 1.11 (95% CI, 0.88 to 1.41). There was no significant difference in graft failure for kidneys with versus without ATN (8% versus 5%). In stratified analyses, the adjusted RR for DGF with ATN was 0.97 (95% CI, 0.7 to 1.34) for non-DCD kidneys and 1.59 (95% CI, 1.23 to 2.06) for DCD kidneys (P=0.02 for the interaction between ATN and DCD on the development of DGF). Despite a modest association with DGF for DCD kidneys, this study reveals no significant associations overall between preimplant biopsy-reported ATN and the outcomes of DGF or graft failure. The potential benefit of more rigorous ATN reporting is unclear, but these findings provide little evidence to suggest that current ATN reports are useful for predicting graft outcomes or deciding to accept or reject allograft offers.
    Clinical Journal of the American Society of Nephrology 02/2014; · 5.07 Impact Factor
  • Chirag R Parikh, Justin M Belcher
    Hepatology 01/2014; · 12.00 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: We frequently fail to identify articles relevant to the subject of acute kidney injury (AKI) when searching the large bibliographic databases such as PubMed, Ovid Medline or Embase. To address this issue, we used computer automation to create information search filters to better identify articles relevant to AKI in these databases. We first manually reviewed a sample of 22 992 full-text articles and used prespecified criteria to determine whether each article contained AKI content or not. In the development phase (two-thirds of the sample), we developed and tested the performance of >1.3-million unique filters. Filters with high sensitivity and high specificity for the identification of AKI articles were then retested in the validation phase (remaining third of the sample). We succeeded in developing and validating high-performance AKI search filters for each bibliographic database with sensitivities and specificities in excess of 90%. Filters optimized for sensitivity reached at least 97.2% sensitivity, and filters optimized for specificity reached at least 99.5% specificity. The filters were complex; for example one PubMed filter included >140 terms used in combination, including 'acute kidney injury', 'tubular necrosis', 'azotemia' and 'ischemic injury'. In proof-of-concept searches, physicians found more articles relevant to topics in AKI with the use of the filters. PubMed, Ovid Medline and Embase can be filtered for articles relevant to AKI in a reliable manner. These high-performance information filters are now available online and can be used to better identify AKI content in large bibliographic databases.
    Nephrology Dialysis Transplantation 01/2014; · 3.37 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: INTRODUCTION: Steroids In caRdiac Surgery trial (SIRS) is a large international randomised controlled trial of methylprednisolone or placebo in patients undergoing cardiac surgery with the use of a cardiopulmonary bypass pump. At the time of surgery, compared with placebo, methylprednisolone divided into two intravenous doses of 250 mg each may reduce the risk of postoperative acute kidney injury (AKI). METHODS AND ANALYSIS: With respect to the study schedule, over 7000 substudy eligible patients from 81 centres in 18 countries were randomised in December 2013. The authors will use a logistic regression to estimate the adjusted OR of methylprednisolone versus placebo on the primary outcome of AKI in the 14 days following surgery (a postoperative increase in serum creatinine of ≥50%, or ≥26.5 μmol/L, from the preoperative value). The stage of AKI will also be considered, as will the outcome of AKI in those with and without preoperative chronic kidney disease. After receipt of grant funding, the authors began to record additional perioperative serum creatinine measurements in consecutive patients enrolled at substudy participating centres, and patients were invited to enroll in a 6-month serum creatinine collection. In these trial subpopulations, the authors will consider the outcome of AKI defined in alternate ways, and the outcome of a 6-month change in kidney function from the preoperative value. ETHICS AND DISSEMINATION: The authors were competitively awarded a grant from the Canadian Institutes of Health Research for this SIRS AKI substudy. Ethics approval was obtained for additional serum creatinine recordings in consecutive patients enrolled at participating centres. The additional kidney data collection first began for patients enrolled after 1 March 2012. In patients who provided consent, the last 6-month kidney outcome data will be collected in 2014. The results will be reported no later than 2015. CLINICAL TRIAL REGISTRATION: Number NCT00427388.
    BMJ Open 01/2014; 4(3):e004842. · 1.58 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Background Kidney damage and reduced kidney function are potent risk factors for heart failure, but existing studies are limited to assessing albuminuria or estimated glomerular filtration rate (eGFR). We evaluated the associations of levels of urinary biomarkers of kidney tubular injury (interleukin 18 [IL-18] and kidney injury molecule 1 [KIM-1]) with future risk of heart failure. Study Design Retrospective cohort study. Setting & Participants 2,917 participants without heart failure in the Health, Aging, and Body Composition (Health ABC) cohort. Predictors Ratios of urine KIM-1, IL-18, and albumin to creatinine (KIM-1:Cr, IL-18:Cr, and ACR, respectively). Outcomes Incident heart failure over a median follow-up of 12 years. Results Median values of each marker at baseline were 812 (IQR, 497-1,235) pg/mg for KIM-1:Cr, 31 (IQR, 19-56) pg/mg for IL-18:Cr, and 8 (IQR, 5-19) mg/g for ACR. 596 persons developed heart failure during follow-up. The top quartile of KIM-1:Cr was associated with risk of incident heart failure after adjustment for baseline eGFR, heart failure risk factors, and ACR (HR, 1.32; 95% CI, 1.02-1.70) in adjusted multivariate proportional hazards models. The top quartile of IL-18:Cr also was associated with heart failure in a model adjusted for risk factors and eGFR (HR, 1.35; 95% CI, 1.05-1.73), but was attenuated by adjustment for ACR (HR, 1.15; 95% CI, 0.89-1.48). The top quartile of ACR had a stronger adjusted association with heart failure (HR, 1.96; 95% CI, 1.53-2.51). Limitations Generalizability to other populations is uncertain. Conclusions Higher urine KIM-1 concentrations were associated independently with incident heart failure risk, although the associations of higher ACR were of stronger magnitude.
    American Journal of Kidney Diseases 01/2014; · 5.29 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Objective Cardiac surgery is a major cause of acute kidney injury. In this setting receipt of blood transfusions appears to associate with a higher risk of AKI, as measured using serum creatinine values. We examined this association further, using urinary biomarkers of kidney injury. Methods 1210 adults underwent cardiac surgery and were divided into three groups based on the receipt of intraoperative packed red blood cell units (PRBC): no blood (n=894), ≤ 2 PRBC (n=206) and > 2 PRBC (n=110). AKI was defined as: i) Doubling of serum creatinine from the pre-operative value; ii) first post-operative urinary interleukin-18 in the 5th quintile; iii) first post-operative urinary neutrophil gelatinase-associated lipocalin in the 5th quintile. We determined the relative risk for AKI outcome according to PRBC group after adjusting for 12 pre-operative and surgical variables. Using the Sobel test for mediation analysis, we also evaluated the role of biomarkers in causing AKI through alternative pathways. Results AKI was more common in those who received >2 PRBC. In patients receiving > 2 PRBC, the adjusted RRs were 2.3 (95% CI 1.2-4.4, p 0.01), 1.36 (95% CI 1.0-1.9, p 0.05), and 1.34 (95% CI 1.0-1.8, p 0.06) for doubling of serum creatinine, urinary IL-18 in the 5th quintile (>60 pg/ml), and urinary NGAL in the 5th quintile (>102 ng/ml), respectively. Furthermore, the effect of PRBC transfusion on AKI was partially mediated by IL-18. Conclusions Receipt of two or more PRBC during cardiac surgery is associated with a greater risk of AKI defined by serum creatinine and kidney injury biomarkers.
    The Journal of Thoracic and Cardiovascular Surgery. 01/2014;
  • [show abstract] [hide abstract]
    ABSTRACT: Background The study of novel urinary biomarkers of acute kidney injury has expanded exponentially. Effective interpretation of data and meaningful comparisons between studies require awareness of factors that can adversely affect measurement. We examined how variations in short-term storage and processing might affect the measurement of urine biomarkers. Study Design Cross-sectional prospective. Setting & Participants Hospitalized patients from 2 sites: Yale New Haven Hospital (n = 50) and University of California, San Francisco Medical Center (n = 36). Predictors We tested the impact of 3 urine processing conditions on these biomarkers: (1) centrifugation and storage at 4°C for 48 hours before freezing at −80°C, (2) centrifugation and storage at 25°C for 48 hours before freezing at −80°C, and (3) uncentrifuged samples immediately frozen at −80°C. Outcomes Urine concentrations of 5 biomarkers: neutrophil gelatinase-associated lipocalin (NGAL), interleukin 18 (IL-18), kidney injury molecule 1 (KIM-1), liver-type fatty acid–binding protein (L-FABP), and cystatin C. Measurements We measured urine biomarkers by established enzyme-linked immunosorbent assay methods. Biomarker values were log-transformed, and agreement with a reference standard of immediate centrifugation and storage at −80°C was compared using concordance correlation coefficients (CCCs). Results Neither storing samples at 4°C for 48 hours nor centrifugation had a significant effect on measured levels, with CCCs higher than 0.9 for all biomarkers tested. For samples stored at 25°C for 48 hours, excellent CCC values (>0.9) also were noted between the test sample and the reference standard for NGAL, cystatin C, L-FABP and KIM-1. However, the CCC for IL-18 between samples stored at 25°C for 48 hours and the reference standard was 0.81 (95% CI, 0.66-0.96). Limitations No comparisons to fresh, unfrozen samples; no evaluation of the effect of protease inhibitors. Conclusions All candidate markers tested using the specified assays showed high stability with both short-term storage at 4°C and without centrifugation prior to freezing. For optimal fidelity, urine for IL-18 measurement should not be stored at 25°C before long-term storage or analysis.
    American Journal of Kidney Diseases 01/2014; 63(4):567–572. · 5.29 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Background Acute kidney injury (AKI) is a serious complication of cardiac operations for which there remains no specific therapy. Animal data and several observational studies suggest that statins prevent AKI, but the results are not conclusive, and many studies are retrospective in nature. Methods We conducted a multicenter prospective cohort study of 625 adult patients undergoing elective cardiac operations. All patients were taking statins and were grouped according to whether statins were continued or held in the 24 hours before operation. The primary outcome was AKI as defined by a doubling of serum creatinine or dialysis. The secondary outcome was the peak level of several kidney injury biomarkers. The results were adjusted for demographic and clinical factors. Results Continuing (vs holding) a statin before operation was not associated with a lower risk of AKI, as defined by a doubling of serum creatinine or dialysis (adjusted relative risk [RR] 1.09; 95% confidence interval [CI] 0.44, 2.70). However, continuing a statin was associated with a lower risk of elevation of the following AKI biomarkers: urine interleukin-18, urine neutrophil gelatinase-associated lipocalin, urine kidney injury molecule-1, and plasma neutrophil gelatinase-associated lipocalin (adjusted RR 0.34; 95% CI 0.18, 0.62), (adjusted RR 0.41; 95% CI 0.22, 0.76), (adjusted RR 0.37; 95% CI 0.20, 0.76), (adjusted RR 0.62; 95% CI 0.39, 0.98), respectively. Conclusions Statins may prevent kidney injury after cardiac operations, as evidenced by lower levels of kidney injury biomarkers.
    The Annals of Thoracic Surgery. 01/2014;
  • [show abstract] [hide abstract]
    ABSTRACT: -Rather than the absolute dose of diuretic or urine output, the primary signal of interest when evaluating diuretic responsiveness is the efficiency with which the kidneys can produce urine after a given dose of diuretic. As a result, we hypothesized that a metric of diuretic efficiency (DE) would capture distinct prognostic information beyond that of raw fluid output or diuretic dose. -We independently analyzed two cohorts: 1) consecutive admissions at the University of Pennsylvania (Penn) with a primary discharge diagnosis of HF (n=657) and 2) patients in the ESCAPE dataset (n=390). DE was estimated as the net fluid output produced per 40 mg of furosemide equivalents, then dichotomized into high vs. low DE based on the median value. There was only a moderate correlation between DE and both the IV diuretic dose and net fluid output (r(2) ≤ 0.26 for all comparisons), indicating that the diuretic efficiency was describing unique information. With the exception of metrics of renal function and pre-admission diuretic therapy, traditional baseline characteristics including right heart catheterization variables were not consistently associated with DE. Low DE was associated with worsened survival even after adjusting for in-hospital diuretic dose, fluid output, in addition to baseline characteristics (Penn HR=1.36, 95% CI 1.04-1.78, p=0.02; ESCAPE HR= 2.86, 95% CI 1.53-5.36, p=0.001. -Although in need of validation in less selected populations, low diuretic efficiency during decongestive therapy portends poorer long-term outcomes above and beyond traditional prognostic factors in patients hospitalized with decompensated heart failure.
    Circulation Heart Failure 12/2013; · 6.68 Impact Factor
  • Chirag R Parikh, Gang Han
    American Journal of Kidney Diseases 12/2013; 62(6):1023-1026. · 5.29 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Acute kidney injury (AKI) is common in patients with cirrhosis and associated with significant mortality. The most common etiologies of AKI in this setting are pre-renal azotemia (PRA), acute tubular necrosis (ATN) and hepatorenal syndrome (HRS). Accurately distinguishing the etiology of AKI is critical as treatments differ markedly. However, establishing an accurate differential diagnosis is extremely challenging. Urinary biomarkers of kidney injury distinguish structural from functional causes of AKI and may facilitate more accurate and rapid diagnoses. We conducted a multi-center, prospective cohort study of patients with cirrhosis and AKI assessing multiple biomarkers for differential diagnosis of clinically adjudicated AKI. Patients (n=36) whose creatinine returned to within 25% of their baseline within 48 hours were diagnosed with PRA. 76 patients with progressive AKI were diagnosed via blinded retrospective adjudication. Of these progressors, thirty-nine (53%) patients were diagnosed with ATN, 19 (26%) with PRA and 16 (22%) with HRS. Median values for neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18), kidney injury molecule-1 (KIM-1), liver-type fatty acid binding protein (L-FABP) and albumin differed between etiologies and were significantly higher in patients adjudicated with ATN. The fractional excretion of sodium (FENa) was lowest in patients with HRS, 0.10%, but did not differ between those with PRA, 0.27%, or ATN, 0.31%, p=0.54. The likelihood of being diagnosed with ATN increased step-wise with number of biomarkers above optimal diagnostic cutoffs. Conclusion: Urinary biomarkers of kidney injury are elevated in patients with cirrhosis and AKI due to ATN. Incorporating biomarkers into clinical decision making has the potential to more accurately guide treatment by establishing which patients have structural injury underlying their AKI. Further research is required to document biomarkers specific to HRS. (Hepatology 2013;)
    Hepatology 12/2013; · 12.00 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: -The long-term durability and prognostic significance of improvement in renal function following mechanical circulatory support (MCS) has yet to be characterized in a large multicenter population. The primary goals of this analysis were to describe serial post-MCS changes in estimated glomerular filtration rate (eGFR) and determine their association with all-cause mortality. -Adult patients enrolled in INTERMACS with serial creatinine levels available (n=3,363) were studied. Early post-MCS, eGFR improved substantially (median improvement 48.9%, p<0.001) with 22.3% of the population improving their eGFR by ≥100% within the first few weeks. However, in the majority of patients this improvement was transient, and by one year, eGFR was only 6.7% above the pre-MCS value (p<0.001). This pattern of early improvement followed by deterioration in eGFR was observed with both pulsatile and continuous-flow devices. Interestingly, poor survival was associated with both marked improvement (adjusted HR=1.64, 1.19-2.26, p=0.002) and worsening in eGFR (adjusted HR=1.63, 1.15-2.13, p=0.004). -Post-MCS, early improvement in renal function is common but appears to be largely transient and not necessarily indicative of an improved prognosis. This pattern was observed with both pulsatile and continuous-flow devices. Additional research is necessary to better understand the mechanistic basis for these complex post-MCS changes in renal function and their associated survival disadvantage. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00119834.
    Circulation Heart Failure 11/2013; · 6.68 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Differentiation of HF-induced renal dysfunction (RD) from irreversible intrinsic kidney disease is challenging, likely related to the multifactorial pathophysiology underlying HF-induced RD. In contrast, HF-induced liver dysfunction results in characteristic laboratory abnormalities. Given that similar pathophysiologic factors are thought to underlie both conditions, and that the liver and kidneys share a common circulatory environment, patients with laboratory evidence of HF-induced liver dysfunction may also have a high incidence of potentially reversible HF-induced RD. Hospitalized patients with a discharge diagnosis of HF were reviewed (n = 823). Improvement in renal function (IRF) was defined as a 20% improvement in estimated glomerular filtration rate (eGFR). An elevated international normalized ratio (INR; odds ratio [OR] 2.8; P < .001), bilirubin (BIL; OR 2.2; P < .001), aspartate aminotransferase (AST; OR 1.8; P = .004), and alanine aminotransferase (ALT; OR 2.1; P = .001) were all significantly associated with IRF. Among patients with baseline RD (eGFR ≤45 mL min(-1) 1.73 m(-2)), associations between liver dysfunction and IRF were particularly strong (INR: OR 5.7 [P < .001]; BIL: OR 5.1 [P < .001]; AST: OR 2.9 [P = .005]; ALT: OR 4.8 [P < .001]). Biochemical evidence of mild liver dysfunction is associated with reversible RD in decompensated HF patients. In the absence of methodology to directly identify HF-induced RD, signs of HF-induced dysfunction of other organs may serve as an accessible method by which HF-induced RD is recognized.
    Journal of cardiac failure 11/2013; 19(11):739-745. · 3.25 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Of patients undergoing cardiac surgery in the United States, 15% to 20% are re-hospitalized within 30 days. Current models to predict readmission have not evaluated the association between severity of postoperative acute kidney injury (AKI) and 30-day readmissions. We collected data from 2,209 consecutive patients who underwent either coronary artery bypass or valve surgery at 7 member hospitals of the Northern New England Cardiovascular Disease Study Group Cardiac Surgery Registry between July 2008 and December 2010. Administrative data at each hospital were searched to identify all patients readmitted to the index hospital within 30 days of discharge. We defined AKI stages by the AKI Network definition of 0.3 or 50% increase (stage 1), twofold increase (stage 2), and a threefold or 0.5 increase if the baseline serum creatinine was at least 4.0 (mg/dL) or new dialysis (stage 3). We evaluate the association between stages of AKI and 30-day readmission using multivariate logistic regression. There were 260 patients readmitted within 30 days (12.1%). The median time to readmission was 9 (interquartile range, 4 to 16) days. Patients not developing AKI after cardiac surgery had a 30-day readmission rate of 9.3% compared with patients developing AKI stage 1 (16.1%), AKI stage 2 (21.8%), and AKI stage 3 (28.6%, p < 0.001). Adjusted odds ratios for AKI stage 1 (1.81; 1.35, 2.44), stage 2 (2.39; 1.38, 4.14), and stage 3 (3.47; 1.85 to 6.50). Models to predict readmission were significantly improved with the addition of AKI stage (c-statistic 0.65, p = 0.001) and net reclassification rate of 14.6% (95% confidence interval: 5.05% to 24.14%, p = 0.003). In addition to more traditional patient characteristics, the severity of postoperative AKI should be used when assessing a patient's risk for readmission.
    The Annals of thoracic surgery 10/2013; · 3.74 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Normal aging results in a predictable decrease in glomerular filtration rate (GFR), and low GFR is associated with worsened survival. If this survival disadvantage is directly caused by the low GFR, as opposed to the disease causing the low GFR, the risk should be similar regardless of the underlying mechanism. Our objective was to determine if age-related decreases in estimated GFR (eGFR) carry the same prognostic importance as disease-attributable losses in patients with ventricular dysfunction. We analyzed the Studies Of Left Ventricular Dysfunction limited data set (n = 6,337). The primary analysis focused on determining if the eGFR-mortality relation differed by the extent to which the eGFR was consistent with normal aging. Mean eGFR was 65.7 ml/min/1.73 m(2) (SD = 19.0). Across the range of age in the population (27 to 80 years), baseline eGFR decreased by 0.67 ml/min/1.73 m(2)/year (95% confidence interval [CI] 0.63 to 0.71). The risk of death associated with eGFR was strongly modified by the degree to which the low eGFR could be explained by aging (p for interaction <0.0001). For example, in a model incorporating the interaction, uncorrected eGFR was no longer significantly related to mortality (adjusted hazard ratio 1.0 per 10 ml/min/1.73 m(2), 95% CI 0.97 to 1.1, p = 0.53), whereas a disease-attributable decrease in eGFR above the median carried significant risk (adjusted hazard ratio 2.8, 95% CI 1.6 to 4.7, p <0.001). In conclusion, in the setting of left ventricular dysfunction, renal dysfunction attributable to normal aging had a limited risk for mortality, suggesting that the mechanism underlying renal dysfunction is critical in determining prognosis.
    The American journal of cardiology 10/2013; · 3.58 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Using either an angiotensin-converting enzyme inhibitor (ACEi) or an angiotensin receptor blocker (ARB) the morning of surgery may lead to 'functional' postoperative acute kidney injury (AKI), measured by an abrupt increase in serum creatinine. Whether the same is true for 'structural' AKI, measured with new urinary biomarkers, is unknown. The TRIBE-AKI study was a prospective cohort study of 1594 adults undergoing cardiac surgery at six hospitals between July 2007 and December 2010. We classified the degree of exposure to ACEi/ARB into three categories: 'none' (no exposure prior to surgery), 'held' (on chronic ACEi/ARB but held on the morning of surgery) or 'continued' (on chronic ACEi/ARB and taken the morning of surgery). The co-primary outcomes were 'functional' AKI based upon changes in pre- to postoperative serum creatinine, and 'structural AKI', based upon peak postoperative levels of four urinary biomarkers of kidney injury. Across the three levels (none, held and continued) of ACEi/ARB exposure there was a graded increase in functional AKI, as defined by AKI stage 1 or worse; (31, 34 and 42%, P for trend 0.03) and by percentage change in serum creatinine from pre- to postoperative (25, 26 and 30%, P for trend 0.03). In contrast, there were no differences in structural AKI across the strata of ACEi/ARB exposure, as assessed by four structural AKI biomarkers (neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, interleukin-18 or liver-fatty acid-binding protein). Preoperative ACEi/ARB usage was associated with functional but not structural acute kidney injury. As AKI from ACEi/ARB in this setting is unclear, interventional studies testing different strategies of perioperative ACEi/ARB use are warranted.
    Nephrology Dialysis Transplantation 09/2013; · 3.37 Impact Factor

Publication Stats

4k Citations
1,157.35 Total Impact Points

Institutions

  • 2005–2014
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States
  • 2013
    • Trinity Western University
      Langley, British Columbia, Canada
  • 2012–2013
    • University of Chicago
      • • Section of Nephrology
      • • Department of Medicine
      Chicago, IL, United States
    • Indiana University-Purdue University Indianapolis
      • Department of Medicine
      Indianapolis, IN, United States
  • 2011–2013
    • San Francisco VA Medical Center
      San Francisco, California, United States
    • McGill University
      • Division of Nephrology
      Montréal, Quebec, Canada
  • 2010–2012
    • University of California, San Francisco
      • • Division of General Internal Medicine
      • • Division of Hospital Medicine
      San Francisco, CA, United States
    • Piedmont Henry Hospital
      Georgia, United States
    • Cincinnati Children's Hospital Medical Center
      • Division of Nephrology and Hypertension
      Cincinnati, OH, United States
  • 2007–2012
    • The University of Western Ontario
      • Division of Nephrology
      London, Ontario, Canada
    • Stony Brook University
      Stony Brook, New York, United States
    • Texas Children's Hospital
      Houston, Texas, United States
  • 2005–2012
    • Yale University
      • • Section of Nephrology
      • • Department of Pediatrics
      • • School of Medicine
      New Haven, CT, United States
  • 2010–2011
    • Dartmouth–Hitchcock Medical Center
      • Department of Surgery
      Lebanon, New Hampshire, United States
    • Wayne State University
      • Department of Internal Medicine
      Detroit, MI, United States
  • 2005–2010
    • University of Illinois at Chicago
      • • Section of Nephrology
      • • Section of General Internal Medicine
      Chicago, IL, United States
  • 2009
    • Fatih University
      • Department of Internal Medicine
      İstanbul, Istanbul, Turkey
  • 2008
    • Baylor College of Medicine
      Houston, Texas, United States
    • Hannover Medical School
      Hanover, Lower Saxony, Germany
    • Mount Sinai School of Medicine
      • Department of Medicine
      Manhattan, NY, United States
    • Kansas City VA Medical Center
      Kansas City, Missouri, United States
  • 2007–2008
    • Virginia Commonwealth University
      • Division of Nephrology
      Richmond, VA, United States
  • 2002–2008
    • University of Colorado
      • • Division of Renal Diseases and Hypertension
      • • Department of Clinical Pharmacy
      • • Department of Medicine
      Denver, CO, United States
    • Nassau County Medical Center
      East Meadow, New York, United States
  • 2004
    • University of Colorado Hospital
      • Department of Medicine
      Denver, Colorado, United States