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The effect of rate of decline of kidney function on risk for death is not well understood. Using the Department of Veterans Affairs national databases, we retrospectively studied a cohort of 4171 patients who had rheumatoid arthritis and early stage 3 chronic kidney disease (CKD; estimated GFR 45 to 60 ml/min) and followed them longitudinally to characterize predictors of disease progression and the effect of rate of kidney function decline on mortality. After a median of 2.6 years, 1604 (38%) maintained stable kidney function; 426 (10%), 1147 (28%), and 994 (24%) experienced mild, moderate, and severe progression of CKD, respectively (defined as estimated GFR decline of 0 to 1, 1 to 4, and >4 ml/min per yr). Peripheral artery disease predicted moderate progression of CKD progression. Black race, hypertension, diabetes, cardiovascular disease, and peripheral artery disease predicted severe progression of CKD. After a median of 5.7 years, patients with severe progression had a significantly increased risk for mortality (hazard ratio 1.54; 95% confidence interval 1.30 to 1.82) compared with those with mild progression; patients with moderate progression exhibited a similar trend (hazard ratio 1.10; 95% confidence interval 0.98 to 1.30). Our results demonstrate an independent and graded association between the rate of kidney function decline and mortality. Incorporating the rate of decline into the definition of CKD may transform a static definition into a dynamic one that more accurately describes the potential consequences of the disease for an individual.

Background: Data regarding health outcomes among living kidney donors are lacking, especially among nonwhite persons., Methods: We linked identifiers from the Organ Procurement and Transplantation Network (OPTN) with administrative data of a private U.S. health insurer and performed a retrospective study of 4650 persons who had been living kidney donors from October 1987 through July 2007 and who had post-donation nephrectomy benefits with this insurer at some point from 2000 through 2007. We ascertained post-nephrectomy medical diagnoses and conditions requiring medical treatment from billing claims. Cox regression analyses with left and right censoring to account for observed periods of insurance benefits were used to estimate absolute prevalence and prevalence ratios for diagnoses after nephrectomy. We then compared prevalence patterns with those in the 2005-2006 National Health and Nutrition Examination Survey (NHANES) for the general population., Results: Among the donors, 76.3% were white, 13.1% black, 8.2% Hispanic, and 2.4% another race or ethnic group. The median time from donation to the end of insurance benefits was 7.7 years. After kidney donation, black donors, as compared with white donors, had an increased risk of hypertension (adjusted hazard ratio, 1.52; 95% confidence interval [CI], 1.23 to 1.88), diabetes mellitus requiring drug therapy (adjusted hazard ratio, 2.31; 95% CI, 1.33 to 3.98), and chronic kidney disease (adjusted hazard ratio, 2.32; 95% CI, 1.48 to 3.62); findings were similar for Hispanic donors. The absolute prevalence of diabetes among all donors did not exceed that in the general population, but the prevalence of hypertension exceeded NHANES estimates in some subgroups. End-stage renal disease was identified in less than 1% of donors but was more common among black donors than among white donors., Conclusions: As in the general U.S. population, racial disparities in medical conditions occur among living kidney donors. Increased attention to health outcomes among demographically diverse kidney donors is needed. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.)

Purpose of Review: Acute phosphate nephropathy (APN) has been identified in renal biopsy specimens of patients exposed to oral sodium phosphate (OSP) bowel purgatives. Biopsy confirmed cases presented with bland urinary sediment, low-grade proteinuria, and varying degrees of creatinine elevation. Prospective identification of APN is difficult in that definitive diagnosis requires renal biopsy, and biopsy is rarely performed for patients with this clinical presentation., Recent Findings: Observational studies evaluating acute kidney injury after OSP exposure using interval changes in creatinine as a surrogate for APN have reported conflicting results. Although these studies have produced estimates of disease occurrence, they have been unable to definitively quantify the overall risk of APN with OSP as compared with alternative bowel-cleansing agents., Summary: On the basis of association of APN and OSP, the US Food and Drug Administration issued a boxed warning and manufacturers have ceased production and distribution of some OSP products. As this is a temporary solution, more studies are needed to delineate the pathophysiology of this disease and to better identify the subset of the population at risk for APN.

Background: The cardiac implications of obesity in kidney transplant recipients are not well-described., Methods: We examined associations of body mass index (BMI) at transplant with posttransplant cardiac risk among 1102 renal allograft recipients at a single center in 1991 to 2004. Cumulative posttransplant incidences of congestive heart failure (CHF), atrial fibrillation (AF), myocardial infarction, and a composite of these cardiac diagnoses were estimated by the Kaplan-Meier method. Bivariate (hazards ratio) and covariate (adjusted hazards ratio) relationships of BMI increments with cardiac risk were modeled by Cox's regression. We also systematically reviewed the literature on BMI and cardiac events after transplant., Results: In the local data, 5-year cumulative incidence of any cardiac diagnosis rose from 8.67% to 29.35% across the lowest to highest BMI quartiles (P=0.02), driven primarily by increases in CHF and AF. In contrast, the rate of myocardial infarction did not differ by BMI quartile (P=0.56). Each 5 U BMI increase predicted 25% higher risk of the cardiac composite (hazards ratio 1.25, 95% CI 1.07-1.47, P=0.005), a relationship that persisted with significance after covariate adjustment (adjusted hazards ratio 1.19, 95% CI 1.00-1.43, P=0.049). BMI independently predicted cardiac risk in subcohorts with pretransplant heart disease and with nondiabetic renal failure. Data from 26 original articles support BMI as a risk factor for posttransplant CHF and AF, whereas findings for coronary/ischemic outcomes are inconsistent and predominantly negative., Conclusions: High BMI at transplant predicts increased cardiac risk, especially of CHF and AF. Further research should examine whether obesity treatment modifies cardiac risk after kidney transplantation.

Background and Objectives: Racial disparities in provision of healthcare are widespread in the United States but have not been specifically assessed in provision of chronic kidney disease (CKD) care., Design, Setting, Participants, & Measurements: We conducted a retrospective cohort study of the clinical database used in a Department of Defense (DOD) medical system. Beneficiaries studied were DOD-eligible beneficiaries with CKD stage 3 (n = 7729) and 4 (n = 589) using the modified Modification of Diet in Renal Disease (MDRD)-estimated GFR formula but requiring manual correction for Black race. Compliance with selected Kidney Disease Outcomes Quality Initiative (KDOQI) CKD recommended targets (monitoring of recommended laboratory data, prescription of recommended medications, and referral to nephrology) was assessed over a 12-mo period, stratified by CKD stage. Logistic regression analysis was used to assess whether race (White, Black, or other) was independently associated with provider compliance with targets, adjusted for demographic factors and burden of comorbid conditions., Results: Among the targets, only monitoring of LDL cholesterol was significantly less common among Blacks. For all other measures, compliance was either not significantly different or significantly higher for Black compared with White beneficiaries. However, patients categorized as "Other" race were in general less likely to achieve targets than Whites, and at stage 3 CKD significantly less likely to achieve targets for monitoring of phosphorous, hemoglobin, and vitamin D., Conclusions: In the DOD health system, provider compliance with selected CKD stage 3 and 4 targets was not significantly lower for Black beneficiaries than for Whites, with the exception of LDL cholesterol monitoring. Patients classified as Other race were generally less likely to achieve targets than Whites, in some patients significantly so.

Oral sodium phosphate (OSP) is a commonly used purgative before colonoscopy. There have been numerous reports of acute phosphate nephropathy attributed to the use of OSP. This study evaluated the association between the use of OSP and acute kidney injury (AKI) in an observational, retrospective, cohort study. Of 9799 patients who underwent colonoscopy and had serum creatinine values recorded within 365 days before and after the procedure, AKI, defined as > or =50% increase in baseline serum creatinine, was identified in 114 (1.16%). After adjustment for significant covariates in a multiple logistic regression model, the use of OSP was associated with increased risk for AKI (odds ratio 2.35; 95% confidence interval 1.51 to 3.66; P < 0.001) with an adjusted number need to harm of 81. Age was also independently associated with AKI in this cohort; therefore, until larger, prospective studies define the population at risk for acute phosphate nephropathy, the use of polyethylene glycol-based purgatives should be considered for older patients and possibly for those with comorbid medical conditions.

Background: Patients with diabetes mellitus (DM) are at increased risk of contrast-associated nephropathy irrespective of their baseline creatinine (Cr). We tested the efficacy of N-acetylcysteine (NAC) relative to hydration in unselected patients (irrespective of baseline Cr) with DM., Methods: We conducted a randomized open-label study comparing hydration alone (combined oral and rapid intravenous hydration, n = 69) to NAC plus hydration (similar hydration protocol plus NAC 600 mg BID x 4 doses, n = 68) in diabetic patients (mean age 65 +/- 10 years, 65% men) undergoing elective coronary angiography. The primary end point was the mean change in serum Cr measured up to 96 hours postangiography., Results: Baseline Cr was 1.14 +/- 0.43 mg/dL (Cr > or = 1.3 mg/dL in 37 subjects). Baseline characteristics including blood urea nitrogen, Cr, and contrast volume were similar between the 2 groups. The mean Cr change in the NAC group was 0.14 +/- 0.47 versus 0.08 +/- 0.11 mg/dL in the hydration only group (P = NS). Contrast-associated nephropathy, defined as a > or = 0.5 mg/dL increase in Cr, was significantly more common in the NAC group, 9.2% versus 1.4%, P = .043. Similar results were found in the subgroup of participants with either an increased baseline serum Cr (> or = 1.3 mg/dL) or in those receiving high contrast volumes (> 100 mL)., Conclusions: N-Acetylcysteine provides no benefit over an aggressive hydration protocol in patients with DM undergoing coronary angiography.

Background: In the United States, transjugular renal biopsies using the Quickcore side cut needle system have previously been described primarily for transjugular renal biopsy in patients with concurrent liver and kidney disease., Methods: We describe transjugular renal biopsy with the Quickcore trade mark system in 9 patients with nephrotic syndrome and contraindications to percutaneous renal biopsy, who underwent biopsy between 23 October 1996 and 12 April 2001. The most common contraindication was oral anticoagulation with coumadin (40%). Other contraindications included horseshoe kidney, severe renal failure, and spontaneous coagulopathy. A 62 cm straight catheter and 60 cm side-cut Quickcore biopsy needle were used to obtain cortical tissue. Packing of the biopsy tract with Gelfoam was used for venographically identified capsular perforation., Results: Ten procedures were performed on 9 patients with one requiring re-biopsy (5% of all renal biopsies performed at our institution). There were 9 transjugular renal biopsy and one combined liver-kidney biopsy. A mean of 4 +/- 2 passes were made, with a mean of 3 +/- 1 cores obtained per procedure. Histologic diagnosis was made in 90% of biopsies and in 100% of patients. Two patients developed transient hydronephrosis associated with gross hematuria; both required transfusion. Capsular perforation occurred in 90%. One patient died of bacterial sepsis, unrelated to the biopsy, several days after the procedure., Conclusions: Transjugular renal biopsy appears to be efficacious in high-risk patients, for whom the percutaneous approach is contraindicated, including patients on oral anticoagulation. The transfusion rate in the present study was similar to other American reports using this technique.

Background: Previous reports showed an increased early mortality after chronic dialysis initiation among the end-stage renal disease (ESRD) population. We hypothesized that ESRD patients in the Military Health System (MHS) would have greater access to pre-ESRD care and hence better survival rates during this early high-risk period.Methods: In this retrospective cohort study, using the US Renal Data System database, we identified 1,256,640 patients initiated on chronic dialysis from January 2, 2004 through December 31, 2014, from which a bootstrap sample of 3,984 non-MHS incident dialysis patients were compared with 996 MHS patients. We assessed care by a nephrologist and dietitian, erythropoietin administration, and vascular access use at dialysis initiation as well as all-cause mortality as outcome variables.Results: MHS patients were significantly more likely to have had pre-ESRD nephrology care (adjusted OR [aOR] 2.9; 95% CI 2.3-3.7) and arteriovenous fistula used at dialysis initiation (aOR 2.2; 95% CI 1.7-2.7). Crude mortality rates peaked between the 4th and the 8th week for both cohorts but were reduced among MHS patients. The baseline adjusted Cox model showed significantly lower death rates among MHS vs. non-MHS patients at 6, 9, and 12 months. This survival advantage among MHS patients was attenuated after further adjustment for pre-ESRD nephrology care and dialysis vascular access.Conclusions: MHS patients had improved survival within the first 12 months compared to the general ESRD population, which may be explained in part by differences in pre-ESRD nephrology care and vascular access types. [ABSTRACT FROM AUTHOR]

Clinical practice guidelines for management of chronic kidney disease (CKD) have been developed within the Kidney Disease Outcomes Quality Initiative (K/DOQI). Adherence patterns may identify focus areas for quality improvement. We retrospectively studied contemporary CKD care patterns within a private health system in the United States, and systematically reviewed literature of reported practices internationally. Five hundred and nineteen patients with moderate CKD (estimated GFR 30–59 ml/min) using healthcare benefits in 2002–2005 were identified from administrative insurance records. Thirty-three relevant publications in 2000–2006 describing care in 77,588 CKD patients were reviewed. Baseline demographic traits and provider specialty were considered as correlates of delivered care. Testing consistent with K/DOQI guidelines and prevalence of angiotensin converting enzyme inhibitor/angiotensin receptor blocker (ACEi/ARB) medication prescriptions were ascertained from billing claims. Care descriptions in the literature sample were based on medical charts, electronic records and/or claims. KDOQI-consistent measurements of parathyroid hormone (7.1 vs. 0.6%, P = 0.0002), phosphorus (38.2 vs. 1.9%, P < 0.0001) and quantified urinary protein (23.8 vs. 9.4%, P = 0.008) were more common among CKD patients with versus without nephrology referral in the administrative data. Nephrology referral correlated with increased likelihood of testing for parathyroid hormone and phosphorus after adjustment for baseline patient factors. Use of ACEi/ARB medications was more common among patients with nephrology contact (50.0 vs. 30.0%; P = 0.008) but appeared largely driven by higher comorbidity burden. The literature review demonstrated similar practice patterns. Delivery of CKD care may be monitored by administrative data. There is opportunity for improvement in CKD guideline adherence in practice. [ABSTRACT FROM AUTHOR]

Single-center studies have reported that HIV-associated nephropathy (HIVAN) can occur in children and may have a clinical course and prognosis similar to that of adults. However, the prevalence and survival has not been reported for a national sample of children with HIVAN and end-stage renal disease (ESRD) on dialysis in the United States. We utilized the United States Renal Data System (USRDS) database to determine the prevalence, demographic information, and survival of children with HIVAN and ESRD in the United States. The Kaplan-Meier method was used to estimate survival of children with HIVAN and the log-rank test was used to compare their survival with children with focal segmental glomerulosclerosis (FSGS) and adults with HIVAN. Cox regression analysis was used to model adjusted hazard ratios (AHR) with HIVAN as a cause of ESRD and its impact on mortality during the study period, adjusted for potential confounders. Of the 7,732 patients identified with HIVAN, only 60 were younger than 21 years and were classified as children; 50% were males and the majority (88.3%) was black. The cumulative percentage survival of children with HIVAN at 12, 24, and 36 months was better than adults with HIVAN (76%, 62%, and 54% vs. 60%, 43%, and 34%). Survival of children with HIVAN who started dialysis after 1996 was significantly better than those who started dialysis in or before 1996 (log rank P value <0.043). However, the major factor associated with better survival on Cox proportional hazard analysis was female gender (male vs. female AHR 2.85, 95% confidence interval 1.04–6.73). We conclude that only a small number of children with HIVAN and ESRD have received dialysis in the United States. The prognosis of these children is better than that of adults with HIVAN and among children with HIVAN females have better survival than males. [ABSTRACT FROM AUTHOR]

Body mass index, dialysis modality, and survival: Analysis of the United States Renal Data System Dialysis Morbidity and Mortality Wave II Study. Background. The impact of obesity on survival in end-stage renal disease (ESRD) patients as related to dialysis modality (i.e., a direct comparison of hemodialysis with peritoneal dialysis) has not been assessed adjusting for differences in medication use, follow-up ≥2 years, or accounting for changes in dialysis modality. Methods. We performed a retrospective cohort study of the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Wave II Study (DMMS) patients who started dialysis in 1996, and were followed until October 31 2001. Cox regression analysis was used to model adjusted hazard ratios (AHR) for mortality for categories of body mass index (BMI), both as quartiles and as ≥30 kg/m2 vs. lower. Because such a large proportion of peritoneal dialysis patients changed to hemodialysis during the study period (45.5%), a sensitivity analysis was performed calculating survival time both censoring and not censoring on the date of change from peritoneal dialysis to hemodialysis. Results. There were 1675 hemodialysis and 1662 peritoneal dialysis patients. Among hemodialysis patients, 5-year survival for patients with BMI ≥30 kg/m2 was 39.8% vs. 32.3% for lower BMI ( P < 0.01 by log-rank test). Among peritoneal dialysis patients, 5-year survival for patients with BMI ≥30 kg/m2 was 38.7% vs. 40.4% for lower BMI ( P > 0.05 by log-rank test). In adjusted analysis, BMI ≥ 30 kg/m2 was associated with improved survival in hemodialysis patients (AHR 0.89; 95% CI 0.81, 0.99; P= 0.042) but not peritoneal dialysis patients (AHR = 0.99; 95% CI, 0.86, 1.15; P= 0.89). Results were not different on censoring of change from peritoneal dialysis to hemodialysis. Conclusion. We conclude that any survival advantage associated with obesity among chronic dialysis patients is significantly less likely for peritoneal dialysis patients, compared to hemodialysis patients. [ABSTRACT FROM AUTHOR]

Background: The use and possible effects of factors known to improve outcomes in patients with human immunodeficiency virus associated nephropathy (HIVAN), namely of angiotensin converting enzyme inhibitors (ACE) and antiretroviral therapy, has not been reported for a national sample of dialysis patients. Methods: We conducted a historical cohort study of the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study (DMMS) Wave 2 to identify risk factors associated with increased mortality in these patients. Data were available for 3374 patients who started dialysis and were followed until March 2000. Cox Regression analysis was used to model adjusted hazard ratios (AHR) with HIVAN as a cause of end stage renal disease (ESRD) and its impact on mortality during the study period, adjusted for potential confounders. Results: Of the 3374 patients who started dialysis, 36 (1.1%) had ESRD as a result of HIVAN. Only 22 (61%) of patients with HIVAN received antiretroviral agents, and only nine patients (25%) received combination antiretroviral therapy, and only 14% received ACE inhibitors. Neither the use of multiple antiretroviral drugs (AHR, 0.62, 95% CI, 0.10, 3.86, p = 0.60), or ACE inhibitors were associated with a survival advantage. Patients with HIVAN had an increased risk of mortality (adjusted hazard ratio, 4.74, 95% Confidence Interval, 3.12, 7.32, p < 0.01) compared to patients with other causes of ESRD. Conclusions: Medications known to improve outcomes in HIV infected patients were underutilized in patients with HIVAN. Adjusted for other factors, a primary diagnosis of HIVAN was associated with increased mortality compared with other causes of ESRD. [ABSTRACT FROM AUTHOR]

The article presents comments regarding the risk-benefit balance of oral phosphosoda (OSP) use for bowel preparation. The authors published three studies that used an outcome of acute kidney injury (AKI) or serial creatinine change over a six-month interval. It also showed that the table gives the risk of AKI associated with the different bowel purgatives by age category, which was not part of the original publication but has been requested by various health care providers. They reinforce the manufacturer's own recommendations against the use of OSP in high-risk subjects, such as those with chronic kidney disease.

Experience with delivery of renal replacement therapy (RRT) in support of combat operations by the U.S. military has not been reported since the 1970s. We describe the tri-service military medical experience with RRT in support of Operation Iraqi Freedom. Through December 31, 2006, RRT was provided to 12 individuals inside the theater of operations. Navy medical personnel provided RRT to three patients (two U.S. active duty service members and one host nation individual) aboard the USNS Comfort, a mobile level 4 hospital. Dialysis was performed using conventional single-pass hemodialysis machines equipped with portable reverse osmosis systems. Army and Air Force medical personnel provided RRT to nine patients in theater (eight host nation patients and one U.S. active duty service member), using peritoneal dialysis and continuous renal replacement therapy (CRRT), not requiring trained renal nurses or technicians. Originally, U.S. military personnel with acute kidney injury (AKI) who were evacuated from theater to Landstuhl Regional Medical Center (LRMC), or those who developed AKI at LRMC were transferred to the German civilian medical system, if RRT was required. After creation of a rapid-response dialysis team and, later, positioning of a full-time active duty reserve nephrologist at LRMC, 16 patients received RRT at LRMC. None had required RRT in theater. Renal failure requiring RRT during combat operations remains an unusual but serious event, calling for flexibility in the provision of care. Notably, the Operation Iraqi Freedom experience has highlighted the needs of injured host nation patients with AKI and future military medical planning will need to account for their intratheater renal care. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma as a cause of end-stage renal disease in the United States: Patient characteristics and survival. Background. The patient characteristics and mortality associated with renal cell carcinoma (RCC) as a cause of end-stage renal disease (ESRD) have not been characterized for a national population. Methods. An historical cohort study of renal cell carcinoma (RCC) was conducted from April 1, 1995, to December 31, 1999. Included were 360,651 patients in the United States Renal Data System (USRDS) who were initiated on ESRD therapy with valid causes of ESRD. Results. Of the study population, 1646 patients (0.5%) had RCC. The mean age of patients with RCC was 66.8 ± 14.6 years versus 61.3 ± 16.4 years for patients with other causes of ESRD (P < 0.01 by Student t test). The unadjusted 3-year survival (censored at the date of renal transplantation) of patients with RCC during the study period was 23% versus 36% in all other patients [adjusted hazard ratio (AHR), 1.10, 95% confidence interval (CI) 1.02–1.19, P = 0.019 by Cox regression]. However, patients with RCC who underwent nephrectomy (bilateral or unilateral) had significantly better survival compared to RCC patients who did not (AHR, 0.73, 95% CI, 0.63–0.85, P < 0.01), and their survival was not significantly different in comparison with nondiabetic ESRD patients. Bilateral nephrectomy (vs. unilateral) was not associated with any difference in adjusted mortality. Conclusion. Among patients with ESRD, the demographics of those with RCC were similar to those of patients with RCC in the general population. Overall, patients with RCC had decreased survival compared to patients with other causes of ESRD; those who underwent nephrectomy had significantly better survival than those who did not, with survival comparable to patients with nondiabetic ESRD. [ABSTRACT FROM AUTHOR]