Meaghan S. Cuerden

Intensive Hemodialysis Associates with Improved Survival Compared with Conventional Hemodialysis

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

The Secret of Immortal Time Bias in Epidemiologic Studies

In the March 2007 issue of JASN , Hemmelgarn et al. [1][1] reported a 50% reduction in the risk for all-cause mortality for patients who had chronic kidney disease (CKD) and attended multidisciplinary care (MDC) clinics compared with those who received usual care. Their survival curves showed a

Health Outcomes for Living Kidney Donors with Isolated Medical Abnormalities: A Systematic Review

Individuals with isolated medical abnormalities (IMAs) are undergoing living donor nephrectomy more frequently. Knowledge of health risks for these living donors is important for donor selection, informed consent and follow‐up. We systematically reviewed studies with ≥3 living kidney donors with preexisting IMAs, including older age, obesity, hypertension, reduced glomerular filtration rate (GFR), proteinuria, microscopic hematuria and nephrolithiasis. We abstracted data on study and donor characteristics, perioperative outcomes, longer term renal and blood pressure outcomes and mortality and compared them to those of non‐IMA donors.

Kidney Function After Off-Pump or On-Pump Coronary Artery Bypass Graft Surgery A Randomized Clinical Trial

IMPORTANCE Most acute kidney injury observed in the hospital is defined by sudden mild or moderate increases in the serum creatinine concentration, which may persist for several days. Such acute kidney injury is associated with lower long-term kidney function. However, it has not been demonstrated that an intervention that reduces the risk of such acute kidney injury better preserves long-term kidney function. OBJECTIVES To characterize the risk of acute kidney injury with an intervention in a randomized clinical trial and to determine if there is a difference between the 2 treatment groups in kidney function 1 year later. DESIGN, SETTING, AND PARTICIPANTS The Coronary Artery Bypass Grafting Surgery Off- or On-pump Revascularisation Study (CORONARY) enrolled 4752 patients undergoing first isolated coronary artery bypass graft (CABG) surgery at 79 sites in 19 countries. Patients were randomized to receive CABG surgery either with a beating-heart technique (off-pump) or with cardiopulmonary bypass (on-pump). From January 2010 to November 2011, 2932 patients (from 63 sites in 16 countries) from CORONARY were enrolled into a kidney function substudy to record serum creatinine concentrations during the postoperative period and at 1 year. The last 1-year serum creatinine concentration was recorded on January 18, 2013. MAIN OUTCOMES AND MEASURES Acute kidney injury within 30 days of surgery (≥50% increase in serum creatinine concentration from prerandomization concentration) and loss of kidney function at 1 year (≥20% loss in estimated glomerular filtration rate from prerandomization level). RESULTS Off-pump (n = 1472) vs on-pump (n = 1460) CABG surgery reduced the risk of acute kidney injury (17.5% vs 20.8%, respectively; relative risk, 0.83 [95% CI, 0.72-0.97], P = .01); however, there was no significant difference between the 2 groups in the loss of kidney function at 1 year (17.1% vs 15.3%, respectively; relative risk, 1.10 [95% CI, 0.95-1.29], P = .23). Results were consistent with multiple alternate continuous and categorical definitions of acute kidney injury or kidney function loss, and in the subgroup with baseline chronic kidney disease. CONCLUSIONS AND RELEVANCE Use of off-pump compared with on-pump CABG surgery reduced the risk of postoperative acute kidney injury, without evidence of better preserved kidney function with off-pump CABG surgery at 1 year. In this setting, an intervention that reduced the risk of mild to moderate acute kidney injury did not alter longer-term kidney function. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00463294.

When laboratories report estimated glomerular filtration rates in addition to serum creatinines, nephrology consults increase

Serum creatinine alone can be difficult to interpret as a measure of kidney function such that chronic kidney disease might be under-recognized in the general population. In the province of Ontario, Canada, all outpatient laboratories now report estimated glomerular filtration rate (eGFR) in addition to serum creatinine. To determine the impact of this reporting on clinical practice, we linked health administrative data for more than 8 million adults of age 25 years or older over an almost 10-year period and conducted a population-based intervention analysis with seasonal time-series modeling to determine overall trends in the number and type of patients seen by nephrologists. Compared to the period when only serum creatinines were reported, the number of patients seen in consultation by nephrologists increased after eGFR reporting by an average of 24% (an absolute increase of 2.9 consults per 100,000 adults), an increase of about 23 consults per nephrologist per year. The greatest increases were seen in women (39% increase) and those 80 years of age and older (58% increase). Our study found that eGFR reporting was associated with a sudden increase in the number of nephrology consults. However, it remains to be seen whether the routine reporting of eGFR results in improved treatment and outcomes for those with chronic kidney disease.

Validity of Administrative Database Coding for Kidney Disease: A Systematic Review

BACKGROUND Information in health administrative databases increasingly guides renal care and policy. STUDY DESIGN Systematic review of observational studies. SETTING & POPULATION Studies describing the validity of codes for acute kidney injury (AKI) and chronic kidney disease (CKD) in administrative databases operating in any jurisdiction. SELECTION CRITERIA After searching 13 medical databases, we included observational studies published from database inception though June 2009 that validated renal diagnostic and procedural codes for AKI or CKD against a reference standard. INDEX TESTS Renal diagnostic or procedural administrative data codes. REFERENCE TESTS Patient chart review, laboratory values, or data from a high-quality patient registry. RESULTS 25 studies of 13 databases in 4 countries were included. Validation of diagnostic and procedural codes for AKI was present in 9 studies, and validation for CKD was present in 19 studies. Sensitivity varied across studies and generally was poor (AKI median, 29%; range, 15%-81%; CKD median, 41%; range, 3%-88%). Positive predictive values often were reasonable, but results also were variable (AKI median, 67%; range, 15%-96%; CKD median, 78%; range, 29%-100%). Defining AKI and CKD by only the use of dialysis generally resulted in better code validity. The study characteristic associated with sensitivity in multivariable meta-regression was whether the reference standard used laboratory values (P < 0.001); sensitivity was 39% lower when laboratory values were used (95% CI, 23%-56%). LIMITATIONS Missing data in primary studies limited some of the analyses that could be done. CONCLUSIONS Administrative database analyses have utility, but must be conducted and interpreted judiciously to avoid bias arising from poor code validity.

Reimbursing Live Organ Donors for Incurred Non-Medical Expenses: A Global Perspective on Policies and Programs

Methods to reimburse living organ donors for the non‐medical expenses they incur have been implemented in some jurisdictions and are being considered in others. A global understanding of existing legislation and programs would help decision makers implement and optimize policies and programs.

Economic consequences incurred by living kidney donors: A canadian multi-center prospective study

Some living kidney donors incur economic consequences as a result of donation; however, these costs are poorly quantified. We developed a framework to comprehensively assess economic consequences from the donor perspective including out‐of‐pocket cost, lost wages and home productivity loss. We prospectively enrolled 100 living kidney donors from seven Canadian centers between 2004 and 2008 and collected and valued economic consequences (

International quotidian dialysis registry: Annual report 2009

CAD 2008) at 3 months and 1 year after donation. Almost all (96%) donors experienced economic consequences, with 94% reporting travel costs and 47% reporting lost pay. The average and median costs of lost pay were

Perioperative Aspirin and Clonidine and Risk of Acute Kidney Injury A Randomized Clinical Trial

2144 (SD 4167) and