Early Mortality Among Peritoneal Dialysis and Hemodialysis Patients Who Transitioned With an Optimal Outpatient Start.

INTRODUCTION: Lower early mortality observed in peritoneal dialysis (PD) compared with hemodialysis (HD) may be due to differential pre-end-stage renal disease (ESRD) care and the stable setting of transition to dialysis where PD starts are more frequently outpatient rather than during an unscheduled hospitalization. To account for these circumstances, we compared early mortality among a matched cohort of PD and HD patients who had optimal and outpatient starts. METHODS: Retrospective cohort study performed among patients with chronic kidney disease (CKD) who transitioned to ESRD from 1 January 2002 to 31 March 2015 with an optimal start in an outpatient setting. Optimal start defined as (i) HD with an arteriovenous graft or fistula or (ii) PD. Propensity score modeling factoring age, race, sex, comorbidities, estimated glomerular filtration rate (eGFR) level, and change in eGFR before ESRD was used to create a matched cohort of HD and PD. All-cause mortality was compared at 6 months, 1 year, and 2 years posttransition to ESRD. RESULTS: Among 2094 patients (1398 HD and 696 PD) who had optimal outpatient transition to ESRD, 541 HD patients were propensity score-matched to 541 PD patients (caliper distance <0.001). All-cause mortality odds ratios (OR) in PD compared with HD were 0.79 (0.39-1.63), 0.73 (0.43-1.23), and 0.88 (0.62-1.26) for 6 months, 1 year, and 2 years, respectively. Time-varying analysis accounting for modality switch (19% PD, 1.9% HD) demonstrated a mortality hazard ratio of 0.94 (0.70-1.24). CONCLUSION: Among an optimal start CKD cohort that transitioned to ESRD on an outpatient basis, we found no evidence of differences in early mortality between PD and HD.

Comparisons of sleep apnoea rate and outcomes among patients with resistant and non-resistant hypertension.

BACKGROUND AND OBJECTIVE: We directly compared sleep apnoea (SA) rates and risk of cardiovascular and mortality outcomes among SA patients with resistant hypertension (RH) and non-RH within a large diverse hypertension population. METHODS: A retrospective cohort study between 1 January 2006 and 31 December 2010 among hypertensive adults (age ≥ 18 years) was performed within an integrated health system. Rates of SA in RH and non-RH were determined. Multivariable logistic regression analyses were used to calculate OR for SA. Cox proportional hazard modelling was used to estimate hazard ratios (HRs) for cardiovascular and mortality outcomes between SA in RH versus SA in non-RH adjusting for age, gender, race, BMI, chronic kidney disease and other comorbidities. RESULTS: SA was identified in 33 682 (7.2%) from 470 386 hypertensive individuals. SA in RH accounted for 5806 (9.6%) compared to SA in non-RH 27 876 individuals (6.8%). Multivariable OR (95% CI) for SA was 1.16 (1.12, 1.19), 3.57 (3.47, 3.66) and 2.20 (2.15, 2.25) for RH versus non-RH, BMI ≥ 30, and males, respectively. Compared to SA in non-RH individuals, SA in RH had a multivariable adjusted HR (95% CI) of 1.24 (1.13, 1.36), 1.43 (1.28, 1.61), 0.98 (0.85, 1.12) and 1.04 (0.95, 1.14) for ischaemic heart event (IHE), congestive heart failure (CHF), stroke and mortality, respectively. CONCLUSION: We observed a modest increase in likelihood for SA among RH compared to non-RH patients. Risks for IHE and CHF were higher for SA in RH compared to SA in non-RH patients; however, there were no differences in risk for stroke and mortality.

Comparing cardiac surgery in peritoneal dialysis and hemodialysis patients: perioperative outcomes and two-year survival.

BACKGROUND: We sought to compare perioperative outcomes and 2-year survival in a cohort of peritoneal dialysis (PD) patients compared with matched hemodialysis (HD) patients who underwent cardiothoracic surgery at our institution. METHODS: We obtained a list of all dialysis-dependent patients who underwent cardiac surgery (coronary artery bypass grafting, valve replacement, or both) at our center between 1994 and 2008. All patients undergoing PD at the time of surgery were included in our analysis. Two HD patients matched for age, diabetes status, and Charleston comorbidity score were obtained for each PD patient. RESULTS: The analysis included 36 PD patients and 72 HD patients. Mean age, sex, diabetes status, cardiac unit stay, hospital stay, and operative mortality did not differ by dialysis modality. The incidence of 1 or more postoperative complications (infection, prolonged intubation, death) was higher for HD patients (50% vs. 28% for PD patients, p = 0.046). After surgery, 2 PD patients required conversion to HD. The 2-year survival was 69% for PD patients and 66% for HD patients (p = 0.73). CONCLUSIONS: Our findings suggest that, compared with HD patients, PD patients who require cardiac surgery do not experience more early complications or a lesser 2-year survival and that 2-year survival for dialysis patients after cardiac surgery is acceptable.

Plasma renin activity (PRA) levels and antihypertensive drug use in a large healthcare system.

BACKGROUND: Although hypertension guidelines have utility in treating uncomplicated hypertension, they often overlook the pathophysiologic basis and heterogeneity of hypertension. This may explain the relatively poor hypertension control rates. A proposed approach is to guide addition and subtraction of medications using ambulatory plasma renin activity (PRA) values. To evaluate the heterogeneity of hypertension and the medication burden associated with it, we investigated medication usage in relation to PRA among hypertensive patients within a large ethnically diverse organization. METHODS: A cross sectional data analysis was performed of hypertensive subjects with PRA measurements in the Kaiser Permanente Southern California database between 1 January 1998 and 31 October 2009. RESULTS: Among 7,887 such patients 0, 1, 2, ≥3 medication usage was 16%, 20%, 24%, 40% respectively. PRA levels ranged 1000-fold. Across PRA quartiles (Q1 to Q4) ≥3 meds were prescribed to 50%, 40%, 34%, 37%. From low to high PRA quartiles there was no usage trend for angiotensin converting enzyme inhibitors (ACEIs)/ angiotensin receptor blockers (ARBs) (71%), but diuretics increased (52%, 53%, 57%, 68%), calcium channel blocker's (CCB) fell (56%, 53%, 51%, 42%), and ß-blockers fell (77%, 61%, 49%, 41%). Moreover, systolic BP fell (146, 142, 140, 135 mm Hg), blood urea nitrogen (BUN) rose (16, 17, 18, 20 mg/dl), serum uric acid rose (6.1, 6.3, 6.5, 6.9 mg/dl), and chronic kidney disease rose (22%, 22%, 23%, 27%). CONCLUSIONS: Polytherapy was the norm for treating hypertension. Lower PRAs were associated with higher blood pressures and more medications. Higher PRAs were associated with lower pressures and fewer medications. The results indicate that opportunities exist to simplify antihypertensive therapy by using current ambulatory PRA levels to guide drug selections and subtractions.

Positive relationship of sleep apnea to hyperaldosteronism in an ethnically diverse population.

OBJECTIVE: Approximately, 50-60% of patients with sleep apnea have hypertension. To explore a mechanism of this relationship, we compared its prevalence in a hypertensive population with and without hyperaldosteronism. METHODS: Using the Kaiser Permanente Southern California database, hypertensive individuals who had plasma aldosterone and plasma renin activity measured between 1 January 2006 and 31 December 2007 were evaluated. Hyperaldosteronism was defined as an aldosterone : renin ratio more than 30 and plasma aldosterone more than 20 ng/dl or an aldosterone : renin ratio more than 50 (ng/dl : ng/ml per h). Hypertension was identified by International Classification of Disease, Ninth Revision (ICD-9) coding and sleep apnea was defined by ICD-9 coding or procedural coding for dispensation of positive airway devices. RESULTS: Of 3428 hypertensive patients, 575 (17%) had hyperaldosteronism. Sleep apnea was present in 18% (105) with hyperaldosteronism vs. 9% (251) without hyperaldosteronism (P < 0.001). Odds ratio for sleep apnea in patients with hyperaldosteronism was 1.8 (95% confidence interval 1.3-2.6) after controlling for other sleep apnea risk factors. No ethnic group was at greater risk for sleep apnea. CONCLUSION: The prevalence of sleep apnea in a diverse hypertensive population is increased in patients with hyperaldosteronism, even when controlling for other sleep apnea risk factors.

25-hydroxyvitamin D levels and hypertension rates.

Vitamin D deficiency has been linked to cardiovascular disease and risk factors including hypertension. The authors sought to determine prevalence rates of hypertension in adults tested for 25-hydroxyvitamin D categorized by their levels and evaluate odds ratios for hypertension at lower 25-hydroxyvitamin D levels compared with optimal levels. A cross-sectional study was conducted January 1, 2004, through December 31, 2006, of patients aged 18 years and older within a large ethnically diverse population. Diagnosis of hypertension was determined by International Statistical Classification of Diseases and Related Health Problems codes. Patients were categorized into quartiles according to 25-hydroxyvitamin D levels: ideal (≥40 ng/mL), adequate (30-39 ng/mL), deficient (15-29 ng/mL), and severely deficient (<15 ng/mL). Prevalence rates of hypertension and odds ratios were calculated for each 25-hydroxyvitamin D quartile, adjusting for age, sex, race, and renal insufficiency. A total of 2722 individuals met the inclusion criteria for the study. The overall prevalence of hypertension in the study population was 24%. Hypertension rates were 52%, 41%, 27%, and 20% in 25-hydroxyvitamin D quartiles <15 ng/mL, 15 to 29 ng/mL, 30 to 39 ng/mL, and ≥40 ng/mL, respectively (P<.001). Odds ratios (95% confidence intervals) for hypertension adjusting for age, sex, race, and renal insufficiency were 2.7 (1.4-5.2), 2.0 (1.5-2.6), and 1.3 (1.2-1.6) for 25-hydroxyvitamin D levels <15 ng/mL, 15 to 29 ng/mL, and 30 to 39 ng/mL, respectively, compared with the ≥40 ng/mL group. This study demonstrates increased rates of hypertension in individuals who tested for lower levels of 25-hydroxyvitamin D starting at levels <40 ng/mL. This retrospective analysis raises the question of whether supplementing to optimal vitamin D levels can prevent or improve hypertension.

Vitamin D supplementation and recombinant human erythropoietin utilization in vitamin D-deficient hemodialysis patients.

INTRODUCTION: We sought to examine the impact of ergocalciferol (ERGO) on recombinant human erythropoietin (EPO) use in a cohort of 25-OH vitamin D (25-D)-deficient hemodialysis (HD) patients. METHODS: Baseline 25-D levels were obtained for all patients who received HD >6 months in our unit. Patients with levels between 10 and 30 ng/mL received ERGO 50,000 IU x 4 doses and patients with levels <10 ng/mL received 50,000 IU x 6 doses over a 4-month period. Monthly dose of EPO was recorded at baseline and after ERGO supplementation. RESULTS: Baseline 25-D levels were <30 ng/mL in 89% of tested patients. Eighty-one patients were included in this study. Mean baseline 25-D level was 15.3 ± 7.1 ng/mL and increased to 28.5 ± 8.6 ng/mL after ERGO (p<0.0001), and median baseline EPO dose was 21,933 U/month (interquartile range [IQR] 13,867-35,967) and decreased to 18,400 U/month (IQR 11,050-33,000) after ERGO (p=0.17). Forty-six patients (57%) required less EPO after ERGO compared with baseline: 15,450 U/month (IQR 10,056-23,575) vs. 26,242 U/month (IQR 15,717-40,167), respectively (p<0.0001). Thirty-five patients (43%) required a higher dose of EPO after ERGO, 26,350 U/month (IQR 15,875-46,075) vs. 17,667 U/month (IQR 12,021-23,392), respectively (p=0.016). Mean age, sex, vintage, diabetes status, race and 25-D levels did not differ in these 2 groups of patients, either at baseline or after ERGO. Monthly hemoglobin, iron saturation, albumin, intact parathyroid hormone, calcium and phosphorus were unchanged after ERGO in these 2 groups. CONCLUSIONS: ERGO use in 25-D-deficient HD patients may lessen the need for EPO. We recommend more aggressive supplementation with ERGO in future studies to achieve levels >30 ng/mL.

Review article: Managing sleep apnoea in kidney diseases.

A higher prevalence of sleep apnoea (SA) has been observed in the chronic kidney disease (CKD) population compared with estimates in the general population. Increased rates of SA have been described in patients with various renal-related diagnoses including dialysis, renal transplant, early-stage CKD and proteinuria. The mechanism or underlying aetiology for this association is different for each type of kidney disease. The extracellular fluid volume and metabolic derangements that characterize the uremic state likely contributes to SA in the dialysis population. SA causing direct renal insults from haemodynamic changes, ischaemic stress, or an intermediary condition such as hypertension, can lead to early CKD and proteinuria. While renal transplantation has cured SA in some patients, the post-transplant state is itself a risk factor for SA. The high prevalence of SA in kidney disease and the associated clinical implications warrant vigilance in diagnosis and treatment of SA in the CKD patient. This review focuses on the prevalence of SA in patients with CKD including dialysis and transplant patients, and those with early-stage CKD and proteinuria. SA may vary in form and aetiology depending on type or stage of CKD. Based on these associations, we discuss our rationale for recommendations on screening and management of SA specific to the CKD population.

Vitamin D deficiency and anemia: a cross-sectional study.

Vitamin D has been suggested to have an effect on erythropoiesis. We sought to evaluate the prevalence of anemia in a population of individuals with vitamin D deficiency compared with those with normal levels in a population of a large integrated healthplan. A cross-sectional analysis in the period 1 January 2004 through 31 December 2006 of subjects with documented concurrent levels of 25-hydroxyvitamin D and hemoglobin were evaluated. Vitamin D deficiency was defined as <30 ng/mL and anemia was defined as a hemoglobin <11 g/dL. A total of 554 subjects were included in the analysis. Anemia was present in 49% of 25-hydroxyvitamin D-deficient subjects compared with 36% with normal 25-hydroxyvitamin D levels (p < 0.01). Odds ratio for anemia in subjects with 25-hydroxyvitamin D deficiency using logistic regressions and controlling for age, gender, and chronic kidney disease was 1.9 (95% CI 1.3-2.7). 25-hydroxyvitamin D-deficient subjects had a lower mean Hb (11.0 vs. 11.7; p = 0.12 ) and a higher prevalence of erythrocyte stimulating agent use (47% vs. 24%; p < 0.05). This study demonstrates an association of vitamin D deficiency and a greater risk of anemia, lower mean hemoglobin, and higher usage of erythrocyte-stimulating agents. Future randomized studies are warranted to examine whether vitamin D directly affects erythropoiesis.

Sleep apnea in early and advanced chronic kidney disease: Kaiser Permanente Southern California cohort.

BACKGROUND: Sleep apnea (SA) has been reported to be highly prevalent in the dialysis population. The reported rates of SA in dialysis are severalfold greater than the 2 to 4% estimated in the general population. This study sought to determine whether an association exists between SA and early stages of chronic kidney disease (CKD) where SA may represent an important comorbidity and potential risk factor in kidney disease. METHODS: Cross-sectional study of adults from an integrated health plan with documented serum creatinine levels in the period January 1, 2002, through December 31, 2004. SA diagnosis determined by International Classification of Diseases, ninth revision, coding for SA and Current Procedural Terminology coding for positive airway pressure devices. Kidney function was determined by the estimated glomerular filtration rate (eGFR). Logistic was regression used to estimate the relative risk for SA. RESULTS: The overall prevalence of SA was 2.5% in the study population that included subjects with normal renal function and those with CKD. The odds ratios (ORs) for SA by eGFRs of 75 to 89, 60 to 74, 45 to 59, 30 to 44, and 15 to 29 mL/min per 1.73 m(2), respectively, compared to normal kidney function, after adjustment for age, sex, and number of visits, were as follows: 1.22 (95% confidence interval [CI], 1.18 to 1.25); 1.32 (95% CI, 1.27 to 1.37); 1.42 (95% CI, 1.35 to 1.50); 1.37 (95% CI, 1.25 to 1.50); and 1.32 (95% CI, 1.13 to 1.55). The increased ORs for eGFRs > 45 mL/min per 1.73 m(2) were sustained even after controlling for diabetes, heart failure, and hypertension. CONCLUSION: This study demonstrated an increased risk of SA in patients with early CKD. Further evidence of a causal relationship should be sought in the hope that the detection and management of SA may improve the course of CKD.

Hospitalization rates in daily home hemodialysis versus peritoneal dialysis patients in the United States.

BACKGROUND: Daily hemodialysis (DHD) is associated with improvements in hypertension, left ventricular hypertrophy, mineral metabolism, nutrition, and quality of life, but efficacy is uncertain because of potential selection bias. To reduce the influence of selection bias, we sought to compare hospital admissions for our population of DHD patients with peritoneal dialysis (PD) patients who initiated training during the same period. We also compared our hospital data with the US Renal Data Service database. STUDY DESIGN: Prospective nonrandomized cohort study. SETTING & PARTICIPANTS: 22 (16 male) DHD and 64 (33 male) PD patients who initiated training between March 2003 and September 2007 at our center and remained in our program for at least 6 months. PREDICTORS: Dialysis modality (DHD or PD). OUTCOMES: Number of hospital admissions and length of stay. RESULTS: Median age at initiation of training was 52 years (range, 33 to 76 years) for DHD patients versus 54 years (range, 21 to 82 years) for PD patients (P = 0.5), and median vintage was 23 months (range, 0 to 145 months) for DHD patients versus 0 month (range, 0 to 244 months) for PD patients (P < 0.001). Fifty percent of DHD and 56% of PD patients had a diagnosis of diabetes mellitus (P = 0.8). We observed 27 DHD and 82 PD admissions (0.68 and 0.76 admissions/patient-year, respectively) during the study period (P = 0.5). We also observed 130 DHD and 605 PD hospital days (3.3 and 5.6 days/patient-year, respectively; P < 0.001). LIMITATIONS: Patients were not randomly assigned between the study group and control group; study group was small. CONCLUSIONS: Our study suggests that despite similar patient demographics, patients treated with DHD spend fewer days in the hospital than PD patients in the United States. Although selection bias could partially explain our lower hospitalization rate, other factors, including improvements in blood pressure control, nutrition, and fewer fluctuations in dry weight, probably contributed to the stability of our patients.

Comparison of outcomes of peritoneal dialysis catheters placed by the fluoroscopically guided percutaneous method versus directly visualized surgical method.

PURPOSE: To compare complications in catheters placed by the fluoroscopically guided percutaneous method versus directly visualized surgery. MATERIALS AND METHODS: A retrospective cohort analysis was performed. Mechanical complication rate data, including catheter leakage, malfunction, malposition, and bleeding, were compared between the two groups over a 1-year follow-up period. Additionally, exit site infection rates, tunnel infection rates, and peritonitis episodes were evaluated based on the incidence within 30 days of insertion and 30 days to 1 year after insertion. RESULTS: A total of 101 patients were analyzed (52 in the fluoroscopic guidance group, 49 in the direct visualization group). Prevalence of diabetes was similar: 56% in the directly visualized surgery group and 47% in the fluoroscopically guided treatment group (P = .37). Although the difference was not significant, complication rates tended to be higher in the directly visualized surgery group compared with the percutaneous placement group. These included catheter leakage (13% vs 4%; P = .093), malfunction (11% vs 9%; P = .73), malposition (13% vs 6%; P = .20), and bleeding (8% vs 2%; P = .21). There were no differences in early and late exit site infections and tunnel infections. Late peritonitis rates were lower in the percutaneous placement group (20%) than in the direct visualization group (42%) (P = .018). Diabetic patients had approximately six times greater risk of catheter malfunction than nondiabetic patients regardless of method of catheter insertion. CONCLUSIONS: Placement of peritoneal dialysis catheters percutaneously with fluoroscopic guidance is as safe as placement with direct visualization techniques.

Sleep apnea and hypertension: prevalence in chronic kidney disease.

The authors sought to evaluate the prevalence of hypertension (HTN) in patients with sleep apnea (SA) who had normal kidney function and in patients with SA and chronic kidney disease (CKD). It has not been determined whether there is an effect of interplay of SA and CKD on the prevalence of HTN. In this study, the diagnosis of CKD was established based on the glomerular filtration rate and the presence of proteinuria. SA and HTN were diagnosed based on International Classification of Diseases, Ninth Revision coding, Current Procedural Terminology coding, and medication use. Using the database of a large integrated health system, 434,388 patients aged 18 years and older with 2 or more years of continuous enrollment during January 2002 to December 2004 were analyzed. The HTN rate with SA alone was 51%, compared with 70.2% with SA and CKD. The overall prevalence of HTN was 28% in patients without CKD or SA. The prevalence ratio for HTN was 1.36 (95% confidence interval, 1.33-1.39) more prevalent in patients with SA and CKD compared with patients with SA without CKD. The high prevalence of HTN in patients with SA and CKD suggests the need for evaluation of SA in patients with concurrent HTN and CKD.

Daily home hemodialysis at a health maintenance organization: three-year experience.

Daily home hemodialysis (DHD), 5 to 7 short-duration hemodialysis treatments per week, promotes self-care and has beneficial effects on a number of clinical outcomes including blood pressure and volume control, electrolyte balance, uremic symptoms and sequelae, and quality of life. We sought to demonstrate that DHD is feasible and confers clinical benefits that permit savings in overall healthcare costs despite expenditures on program infrastructure and supplies. We examined the following outcomes monthly for all patients: laboratory values, dialysis adequacy, hospital admission records, surgical and interventional radiology records, and prescription medication usage. Twelve patients completed training in our home hemodialysis unit between April 2003 and April 2006. The mean age at the time of training was 58 years and mean vintage was 62 months. The mean treatment time was 147 min, and the mean number of treatments performed was 5.3 per week. When 1 patient with morbid obesity was excluded due to intentional weight loss, the mean dry weight at initiation of training was 71.9+/-12.4 kg and increased to 74.3+/-12.4 kg by the end of the study (p=0.66). The mean albumin increased from a baseline of 3.9+/-0.3 to 4.3+/-1.1 gm/dL during DHD (p=0.0015). The mean serum phosphorus levels were 5.4+/-1.4 mg/dL. Phosphate binder usage increased from a mean baseline of 2.6+/-1.4 to 4.2+/-2.6 tablets per meal during DHD (p=0.08). The mean delivered single pool Kt/V was 0.87 per treatment. During the 234 months studied, there were 11 hospital admissions (0.56 admissions per patient per year), with a mean length of stay of 3.7 days. Our results demonstrate that DHD improves nutritional status and decreases hospital admissions for dialysis-dependent patients.

Impact of predialysis care on clinical outcomes.

INTRODUCTION: A structured predialysis multidisciplinary team program is beneficial in improving quality of life in patients with end-stage renal disease (ESRD). Educating pre-ESRD patients about their disease is vital in their care. Patients who can identify signs and symptoms of impending problems can seek help and avoid complications that may lead to hospital admissions. Our dialysis center offers two predialysis classes in a structured format. The first class is for those patients with mild to moderate renal disease, whereas the second class is for those with advanced renal disease who are expected to need dialysis in 3 to 6 months. The patients are followed by a multidisciplinary team once they are enrolled in our chronic kidney disease program. METHODS: We retrospectively reviewed all the charts of patients who started dialysis at our center between 1997 and 2000. We identified 68 patients who participated in the predialysis education program and 35 patients who did not because of late referral or refusal to participate. We compared these two groups over a 100-day period (10 days before initial dialysis and 90 days after), for hospitalizations, emergency room (ER) visits, and dialysis access placement. Patients' comorbid conditions, complications, and length of hospitalizations were extracted from the medical records. RESULTS: The 68 patients who completed the predialysis program had an average age of 60.3 years, a total of 96 hospital days, and 39 ER visits. Average length of hospital stay for these patients was 1.4 days. Three patients (4.4%) required placement of temporary catheters for the initial dialysis. Fifty-one percent of these patients had diabetes mellitus. The 35 patients of average age of 54.9 years who did not go through the program had 347 total hospital days and 39 ER visits. Average length of hospitalization was 9.9 days. Thirteen patients (37%) required temporary catheters for initial dialysis. This group included 16 patients (45.7%) with diabetes. CONCLUSION: Patients who participated in a multidisciplinary predialysis education program had fewer complications, ER visits, and hospitalizations. They also had fewer temporary catheter placements, shorter hospital stays, and reduced costs associated with initial dialysis.