John M. Burkart

Contemporary surgical management of renovascular disease

To examine the treatment methods and early results of renovascular repair in our contemporary patient population, we reviewed our surgical experience during a recent 54-month period. From January 1987 to July 1991, 200 patients ranging in age from 5 to 80 years (mean, 56 years) were operated on for correction of nonatherosclerotic (43 patients) and atherosclerotic (157 patients) renovascular disease. The group included 92 men and 108 women, with blood pressures ranging from 300/198 mm Hg to 120/70 mm Hg (mean, 205/113 mm Hg). Defined by preoperative serum creatinine, 129 patients (65%) had evidence of renal insufficiency (Cr greater than or equal to 1.3 mg/dl), whereas 71 patients (36%) had severe renal insufficiency (Cr greater than 2.0 mg/dl; 11 patients were dependent on dialysis). One hundred forty-seven patients with atherosclerotic renovascular disease (94%) demonstrated organ-specific atherosclerotic damage. Operative management of 291 kidneys included unilateral renal artery repair in 117 patients (58%), bilateral repair in 78 patients (39%), and primary nephrectomy in five patients (2.5%). Simultaneous aortic reconstruction was required in 64 patients (32%). There were five operative deaths (2.5% mortality rate) and four occluded renovascular repairs (1.4% primary failure) within 30 days of surgery. Hypertension was considered cured in 21% and improved in 70% of 195 operative survivors. In 70 patients with severe renal insufficiency before operation, estimated glomerular filtration rate was improved in 49% (8 of 11 patients removed from dialysis), unchanged in 36%, and worsened in 15%. Renal function response was significantly influenced by the site of disease and the operation. Twenty-six additional postoperative deaths occurred during follow-up (range, 6 to 58 months; mean, 24.4 months). Extreme atherosclerotic-renovascular disease, preoperative renal insufficiency, failure to improve renal function, and progression to dependence on dialysis after operation were associated with follow-up deaths. Although most patients had a beneficial outcome, failure to improve extreme renal insufficiency was associated with a rapid rate of death during a relatively short follow-up period.

COMPARISON OF GLYCATED ALBUMIN AND HEMOGLOBIN A1c CONCENTRATIONS IN DIABETIC SUBJECTS ON PERITONEAL AND HEMODIALYSIS

♦ Background: Relative to hemoglobin A1c (HbA1c), percentage of glycated albumin (GA%) more accurately reflects recent glycemic control in diabetic hemodialysis (HD) patients. ♦ Methods: To determine the accuracy of glycemic assays in a larger sample including patients on peritoneal dialysis (PD), HbA1c and GA% were measured in 519 diabetic subjects: 55 on PD, 415 on HD, and 49 non-nephropathy controls. ♦ Results: Mean ± SD serum glucose levels were higher in HD and PD patients relative to non-nephropathy controls (HD 169.7 ± 62 mg/dL, PD 168.6 ± 66 mg/dL, controls 146.1 ± 66 mg/dL; p = 0.03 HD vs controls, p = 0.13 PD vs controls). GA% was also higher in HD and PD patients (HD 20.6% ± 8.0%, PD 19.0% ± 5.7%, controls 15.7% ± 7.7%; p < 0.02 HD vs controls and PD vs controls). HbA1c was paradoxically lower in dialysis patients (HD 6.78% ± 1.6%, PD 6.87% ± 1.4%, controls 7.3% ± 1.4%; p = 0.03 HD vs controls, p = 0.12 PD vs controls). The serum glucose/HbA1c ratio differed significantly between dialysis patients and controls (p < 0.0001 HD vs controls, p = 0.002 PD vs controls), while serum glucose/GA% ratio was similar across groups (p = 0.96 HD vs controls, p = 0.64 PD vs controls). In best-fit multivariate models with HbA1c or GA% as outcome variable, dialysis status was a significant predictor of HbA1c but not GA%. ♦ Conclusions: The relationship between HbA1c and GA% differs in diabetic patients with end-stage renal disease who perform either PD or HD compared to those without nephropathy. HbA1c significantly underestimates glycemic control in peritoneal and hemodialysis patients relative to GA%.

Utilization of inpatient and outpatient resources for the management of hemodialysis access complications

Complications of hemodialysis accesses are a major cause of morbidity in chronic hemodialysis patients. Although several investigators have reported on the utilization of inpatient services for hemodialysis access complications, there is a paucity of data regarding the utilization of outpatient services and temporary accesses for these complications. In this retrospective study, we identified all access-related inpatient admissions and outpatient encounters and procedures performed in an incident cohort of hemodialysis patients. Eighty-eight patients were followed for an average of 487.4 +/- 316.9 days, for a total of 119.1 patient-years of risk. The mean age was 57.0 +/- 14.6 years, with 55% females and 65% blacks; 31% of patients had diabetes mellitus as the primary cause of end-stage renal disease. Patients were referred to our nephrology practice a median of 56 days prior to the placement of a hemodialysis access and a median of 76 days prior to the initiation of hemodialysis. At the initiation of hemodialysis, 48 native arteriovenous fistulas and 40 polytetrafluoroethylene grafts were placed. Only 28 patients (31.8%) had a permanent access placed at least 14 days before the start of hemodialysis, resulting in the placement of 93 temporary accesses during the first week of dialysis therapy. Because of access complications, 21 patients had failure of their primary access, requiring the placement of 33 additional permanent accesses, including six native arteriovenous fistulas, 23 polytetrafluoroethylene grafts, and four permacaths, or an average of 0.28 new accesses per patient-year of risk. During the study period, 45 patients (51%) had at least one access complication. To manage these access complications, 25 fistulograms (0.21 per patient-year of risk) were performed and 116 additional temporary accesses (0.97 per patient-year of risk) were placed, including 50 femoral (43.1%), 52 subclavian (44.8%), and 14 internal jugular (12.1%) catheters. A total of 2.43 inpatient days and 1.05 outpatient encounters per year of patient risk were directly attributed to admissions solely for access complications. There is significant utilization of outpatient services, temporary accesses, and fistulograms in the management of hemodialysis access complications. These services should be included whenever a review of hemodialysis access procedures or costs are undertaken.

Impact of Short Daily Hemodialysis on Restless Legs Symptoms and Sleep Disturbances

BACKGROUND AND OBJECTIVES Restless legs syndrome (RLS) and sleep disturbances are common among in-center hemodialysis patients and are associated with increased morbidity/mortality. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS The FREEDOM study is an ongoing prospective cohort study investigating the benefits of home short daily hemodialysis (SDHD) (6 times/week). In this interim report, we examine the long-term effect of SDHD on the prevalence and severity of RLS, as measured by the International Restless Legs Syndrome (IRLS) Study Group rating scale, and sleep disturbances, as measured by the Medical Outcomes Study sleep survey. RESULTS 235 participants were included in this report (intention-to-treat cohort), of which 127 completed the 12-month follow-up (per-protocol cohort). Mean age was 52 years, 55% had an arteriovenous fistula, and 40% suffered from RLS. In the per-protocol analysis, among patients with RLS, the mean IRLS score improved significantly at month 12, after adjustment for use of RLS-related medications (18 versus 11). Among patients with moderate-to-severe RLS (IRLS score ≥15), there was an even greater improvement in the IRLS score (23 versus 13). The intention-to-treat analysis yielded similar results. Over 12 months, there was decline in the percentage of patients reporting RLS (35% versus 26%) and those reporting moderate-to-severe RLS (59% versus 43%). There was a similar and sustained 12-month improvement in several scales of the sleep survey, after adjustment for presence of RLS and use of anxiolytics and hypnotics. CONCLUSIONS Home SDHD is associated with long-term improvement in the prevalence and severity of RLS and sleep disturbances.

Survival of patients undergoing renal replacement therapy in one center with special emphasis on racial differences

This study compared racial differences in end-stage renal disease (ESRD) in 550 patients starting renal replacement therapy at a large academic dialysis center between January 1, 1990, and December 31, 1993, with follow-up through December 31, 1994. Patient groups were compared with respect to cause of ESRD, comorbid factors at the start of dialysis therapy, choice of modality, transplantation rate, and survival. Fifty-eight percent of the patients were white and 42% were African-American. There was a similar distribution of causes of ESRD between races. African-American patients were less likely to choose peritoneal dialysis as initial therapy (11.6% v 29.3%; P < 0.001) and were less likely to change dialysis modality. Transplantation rates were significantly different between African-American and white patients (9.3% v 27.6%; P < 0.001). African-Americans less frequently received living-related, living-nonrelated, and cadaveric renal transplants. Given differences in transplantation rates and in survival of transplanted patients versus patients on dialysis, survival analysis was performed without censoring for transplantation. A multivariate Cox proportional hazards model was formed, and the following were identified as being significant independent predictors of survival: age, race, age-race interaction, serum albumin at the start of dialysis, activity level at the start of dialysis, and presence of congestive heart failure and cancer. Age had little effect on survival among African-American patients, while it was a significant predictor of survival in white patients. In the group of patients starting dialysis before the age of 30 years, African-American patients had a significantly increased mortality risk compared with white patients. However, white patients older than 50 years had a higher mortality risk; this risk difference increased with age. Racial differences in mortality among older white patients could not be explained by differences in comorbid conditions, transplantation rates, or withdrawal from dialysis.

Re-evaluating the Fistula First Initiative in Octogenarians on Hemodialysis.

BACKGROUND AND OBJECTIVES Octogenarians frequently require maintenance hemodialysis (HD) for treatment of stage renal disease ESRD. Although the Fistula First Initiative recommends creating an arteriovenous fistula as the preferred dialysis access method, vascular access selection should be based on life expectancy and functional status at treatment initiation. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This is a retrospective analysis of 4-year outpatient data (January 1, 2004 through December 31, 2007) of incident octogenarian dialysis population in an academic institution. Thirty-nine of 268 patients were octogenarians with a mean (± SD) age of 83.4 ± 3.4 years, and 25 were men. Kaplan-Meier survival and Fishers post hoc statistical analyses were performed. RESULTS Thirty-seven octogenarian patients selected HD and two selected peritoneal dialysis. Among the 37 HD patients, 29 initiated dialysis with a tunneled cuffed catheter, 6 with an arteriovenous fistula, and 2 with an arteriovenous graft. Three patients regained renal function after an average 112 days and one was lost to follow-up. Of the 33 remaining on HD, 8 required nursing home admission and 25 were discharged home after initiating HD. Among these 33, 19 died and 14 remained on HD at the end of study period. Days on dialysis (mean ± SEM) before death in those discharged to a nursing facility versus home were 52.6 ± 14.7 versus 386.1 ± 90.7 (P < 0.05), respectively. CONCLUSIONS Vascular access planning should include assessment of functional status and life expectancy in octogenarian HD patients.

Systematic Barriers to the Effective Delivery of Home Dialysis in the United States: A Report From the Public Policy/Advocacy Committee of the North American Chapter of the International Society for Peritoneal Dialysis

Home dialysis, currently underused in the United States compared with other industrialized countries, likely will benefit from the newly implemented US prospective payment system. Not only is home dialysis less expensive from the standpoint of pure dialysis costs, but overall health system costs may be decreased by more subtle benefits, such as reduced transportation. However, many systematic barriers exist to the successful delivery of home dialysis. We organized these barriers into the categories of educational barriers (patient and providers), governmental/regulatory barriers (state and federal), and barriers specifically related to the philosophies and business practices of dialysis providers (eg, staffing, pharmacies, supplies, space, continuous quality improvement practices, and independence). All stakeholders share the goal of delivering home dialysis therapies in the most cost- and clinically effective and least problematic manner. Identification and recognition of such barriers is the first step. In addition, we have suggested action plans to stimulate the kidney community to find even better solutions so that collectively we may overcome these barriers.

A comparison of center-based vs. home-based daily hemodialysis for patients with end-stage renal disease

Home hemodialysis has been a therapeutic option for almost 4 decades. The complexity of dialysis equipment has been a factor‐limiting adoption of this modality. We performed a feasibility study to demonstrate the safety of center‐based vs. home‐based daily hemodialysis with the NxStage System One portable hemodialysis device. We also performed a retrospective analysis to determine if clinical effects previously associated with short‐daily dialysis were also seen using this novel device. We conducted a prospective, 2‐treatment, 2‐period, open‐label, crossover study of in‐center hemodialysis vs. home hemodialysis in 32 patients treated at 6 U.S. centers. The 8‐week In‐Center Phase (6 days/week) was followed by a 2‐week transition period and then followed by the 8‐week Home Phase (6 days/week). We retrospectively collected data on hemodialysis treatment parameters immediately preceding the study in a subset of patients. Twenty‐six out of 32 patients (81%) successfully completed the study. Successful delivery of at least 90% of prescribed fluid volume (primary endpoint) was achieved in 98.5% of treatments in‐center and 97.3% at home. Total effluent volume as a percentage of prescribed volume was between 94% and 100% for all study weeks. The composite rate of intradialytic and interdialytic adverse events per 100 treatments was significantly higher for the In‐Center Phase (5.30) compared with the Home Phase (2.10; p=0.007). Compared with the period immediately preceding the study, there were reductions in blood pressure, antihypertensive medications, and interdialytic weight gain. Daily home hemodialysis with a small, easy‐to‐use hemodialysis device is a viable dialysis option for end‐stage renal disease patients capable of self/partner‐administered dialysis.

A multicenter study of noncompliance with continuous ambulatory peritoneal dialysis exchanges in US and Canadian patients

Recent evidence suggested that noncompliance (NC) with continuous ambulatory peritoneal dialysis (CAPD) exchanges may be more common in US than in Canadian dialysis centers. This issue was investigated using a questionnaire-based method in 656 CAPD patients at 14 centers in the United States and Canada. NC was defined as missing more than one exchange per week or more than two exchanges per month. Patients were ensured of the confidentiality of their individual results. Mean patient age was 56 +/- 16 years, 52% were women, and 39% had diabetes. The overall admitted rate of NC was 13%, with a rate of 18% in the United States and 7% in Canada (P < 0.001). NC was more common in younger patients (P < 0.0001), those without diabetes (P < 0.001), and employed patients (P < 0.05). It was also more common in black and Hispanic than in Asian and white patients (P < 0.001). NC was more common in patients prescribed more than four exchanges daily (P < 0.0001) but was not affected by dwell volume. On multiple regression analysis, the independent predictors of NC, in order of importance, were being prescribed more than four exchanges per day, black race, being employed, younger age, and not having diabetes. Being treated in a US unit did not quite achieve significance as a multivariate independent predictor. These findings suggest that NC is not uncommon in CAPD patients and is more frequent in US than in Canadian patients. However, country of residence is less powerful as a predictor of NC than a variety of other demographic and prescription factors.

EFFECTS OF HEMODIALYSIS ON PROSTATE-SPECIFIC ANTIGEN

We undertook a prospective study to evaluate the effects of hemodialysis on serum prostate-specific antigen (PSA) in 26 male patients with end-stage renal disease as a clinical model for assessing the role of the kidney in PSA clearance. Patients ranging in age from fifty-one to eighty-three years (mean 64.8 years) underwent phlebotomy immediately before and after outpatient hemodialysis on a Monday/Wednesday/Friday or Tuesday/Thursday/Saturday schedule, with serum PSA values determined by the Abbott IMX Microparticle Enzyme Immunoassay. The mean +/- standard deviation for all post-dialysis PSA levels, 2.43 +/- 3.74, was significantly greater than that for pre-dialysis levels, 2.11 +/- 3.19 (p = 0.04). However, no statistically significant differences were found on comparing the combined pre- and post-dialysis PSA values over the course of the study (p = 0.2733) or when sequential pre-dialysis (p = 0.28) and post-dialysis (p = 0.92) levels were analyzed separately. We conclude that PSA is not eliminated by hemodialysis, and our results infer that it is not cleared by renal mechanisms.