Determinants of modality selection among incident US dialysis patients: results from a national study

Few studies have comprehensively addressed the association of social factors and elements of pre-end-stage renal disease (ESRD) care with the selection of dialysis modality. This study examines the relative contribution of demographic, medical, social, pre-ESRD, and geographic factors to modality assignment among new ESRD patients. Data were collected from the Dialysis Mortality and Morbidity Wave 2 Study, a national random sample of 4025 patients in 1996 and 1997. In multivariate analyses, the selection of peritoneal dialysis (PD) over hemodialysis (HD) was significantly associated with younger age, white race, fewer comorbid conditions, and lower serum albumin. Greater use of PD was seen in patients who were employed, married, and living with someone before the start of ESRD and in those who were more autonomous and more accomplished educationally. Patients referred earlier to a nephrologist (> 4 mo versus < or =4 mo) and seen more frequently by a nephrologist (> or =2 visits versus < 2 visits) in the pre-ESRD period had greater PD use. Of the factors listed, 25% of the variability (R(2)) in PD use was explained by demographic (4.1%), comorbid (1.2%), social/pre-ESRD (14.5%), and geographic (5.2%) factors. This study identifies several clinical, social, and pre-ESRD factors with the selection of PD, and it underscores the importance of patient education, autonomy, and a strong social support system in improving rates of PD use in the United States. As pre-ESRD patient care is an important contributor to PD use in the United States, greater efforts should be expended in improving its delivery earlier in the pre-ESRD period.     

Morphological differences of the internal thoracic artery in patients with and without coronary artery disease--evaluation by duplex-scanning.

OBJECTIVE: The internal thoracic artery is an established arterial graft for myocardial revascularisation, especially of the left anterior descending artery because of a higher patency rate compared to venous grafts. It has never been investigated, whether there are morphological differences in this vessel between patients with or without coronary artery disease or if they are comparable to morphological changes in the common carotid artery. METHODS: We investigated the internal thoracic artery and the common carotid artery of 24 patients (12 with coronary artery disease, 12 without coronary artery disease) with an ultrasonic system on both sides. The intima-media thickness and the diameter of both vessels were estimated. RESULTS: The intima-media-thickness of the internal thoracic artery was comparable in all patients, independent of the presence of a coronary artery disease (0.51+/-0.11 mm with coronary artery disease, 0.50+/-0.17 mm without coronary artery disease, P>0.05). Compared with this the intima-media-thickness of the common carotid artery was thicker in patients with coronary artery disease (0.84+/-0.13 mm with coronary artery disease, 0.73+/-0.07 mm without coronary artery disease, P< or or =0.014). There was no correlation between the thickness of the internal thoracic artery and the common carotid artery (r=0.018, P>0.05). CONCLUSIONS: It could be demonstrated for the first with non-invasive ultrasound, that the intima-media-complex of the internal thoracic artery is protected of the influence of arteriosclerosis. There are no morphological differences like the intima-media-thickness of the common carotid artery. The proven protective mechanism underlines the widespread use of the internal thoracic artery as a coronary artery bypass graft.     

Associations of dialysis modality and infectious mortality in incident dialysis patients in Australia and New Zealand

BACKGROUND: The aim of the present investigation is to compare rates, types, causes, and timing of infectious death in incident peritoneal dialysis (PD) and hemodialysis (HD) patients in Australia and New Zealand. STUDY DESIGN: Observational cohort study using the Australian and New Zealand Dialysis and Transplant Registry data. SETTING & PARTICIPANTS: The study included all patients starting dialysis therapy between April 1, 1995, and December 31, 2005. PREDICTOR: Dialysis modality. OUTCOMES & MEASUREMENTS: Rates of and time to infectious death were compared by using Poisson regression, Kaplan-Meier, and competing risks multivariate Cox proportional hazards model analyses. RESULTS: 21,935 patients started dialysis therapy (first treatment PD, n = 6,020; HD, n = 15,915) during the study period, and 1,163 patients (5.1%) died of infectious causes (PD, 529 patients; 7.6% versus HD, 634 patients; 4.2%). Incidence rates of infectious mortality in PD and HD patients were 2.8 and 1.7/100 patient-years, respectively (incidence rate ratio PD versus HD, 1.66; 95% confidence interval [CI], 1.47 to 1.86). After performing competing risks multivariate Cox analyses allowing for an interaction between time on study and modality because of identified nonproportionality of hazards, PD consistently was associated with increased hazard of death from infection compared with HD after 6 months of treatment (<6 months hazard ratio [HR], 1.08; 95% CI, 0.76 to 1.54; 6 months to 2 years HR, 1.31; 95% CI, 1.09 to 1.59; 2 to 6 years HR, 1.51; 95% CI, 1.26 to 1.80; >6 years HR, 2.76; 95% CI, 1.76 to 4.33). This increased risk of infectious death in PD patients was largely accounted for by an increased risk of death caused by bacterial or fungal peritonitis. LIMITATIONS: Patients were not randomly assigned to their initial dialysis modality. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Dialysis modality selection significantly influences risks, types, causes, and timing of fatal infections experienced by patients with end-stage kidney disease in Australia and New Zealand.     

Survival differences between peritoneal dialysis and hemodialysis among "large" ESRD patients in the United States

BACKGROUND: It has been hypothesized that peritoneal dialysis compared to hemodialysis may be less effective in large patients with end-stage renal disease (ESRD). METHODS: We tested this hypothesis in a cohort of 134,728 new ESRD patients who were initiated on dialysis from May 1, 1995 to July 31, 1997 using data from United States Renal Data System (USRDS). Cox regression models evaluated the association of body mass index (BMI) in quintiles (8.8-20.9, 20.9-23.5, 23.5-26.1, 26.1-30.0, 30.0-75.2 kg/m(2)) with mortality over 2 years in peritoneal dialysis and hemodialysis patients separately, while time-dependent models evaluated the relative risk (RR) of death by modality for each BMI quintile. RESULTS: For hemodialysis, the adjusted RR of death was greatest for patients with BMI 30.0 (RR = 0.97, 95% CI 0.96-0.99 for diabetic and RR = 0.97, 95% CI 0.95-0.98 for nondiabetic patients) compared with the referent (23.5-26.1; RR = 1.00). For peritoneal dialysis, the RR of death was also higher for patients with a BMI <20.9 (RR = 1.20, 95% CI 1.00-1.43 for diabetic and RR = 1.39, 95% CI 1.19-1.64 for nondiabetic patients) but no survival advantage was associated with higher BMI values. The RR of death (peritoneal dialysis/hemodialysis) for each BMI quintile was 0.99, 1.12, 1.26 (P < 0.01), 1.15 (P < 0.01), and 1.44 (P < 0.0001) for diabetic and were 1.07, 1.01, 0.96, 1.04, and 1.22 (P < 0.01) for nondiabetic patients, respectively. CONCLUSION: We conclude that body size modifies the impact of dialysis modality on mortality risk among new ESRD patients in the United States. The selection of hemodialysis over peritoneal dialysis was associated with a survival advantage in patients with large body habitus.     

Population-based screening for family history of end-stage renal disease among incident dialysis patients

BACKGROUND: We determined the familial aggregation of end-stage renal disease (ESRD) in a large, population-based sample of incident ESRD cases to assess the feasibility of developing a targeted screening and prevention program directed at members of families at high risk for kidney disease. METHODS: Between January 1, 1995, and December 31, 2003, incident dialysis patients in ESRD Network 6 facilities were asked to complete a voluntary questionnaire on family history (FH) of ESRD. Cases with ESRD attributed to Mendelian diseases or urologic causes were excluded. FH was considered present if first- or second-degree relatives had ESRD. De-identified FH data were collated with demographic data at dialysis initiation. RESULTS: More than 46% of eligible patients (25,883/55,929) provided FH information and 22.8% (5,901/25,883) of these reported having a FH of ESRD. FH of ESRD was positively associated with female gender, earlier age at ESRD onset, and primary cause of ESRD, and negatively associated with white race. FH associations with age, race, gender, and primary cause of renal failure remained statistically significant after simultaneous adjustment in a multivariate logistic regression model. CONCLUSIONS: Approximately 23% of incident dialysis patients have close relatives with ESRD. Far more are likely to have relatives with clinically silent proteinuria or chronic kidney disease (CKD), both risk factors for future cardiovascular events and ESRD. Physicians caring for patients with CKD should be aware of the marked familial aggregation of ESRD and consider focusing screening efforts on high-risk family members in an attempt to slow the exponential growth rate of kidney disease.     

Perioperative myocardial infarction in patients with coronary artery disease with and without aorta--coronary artery bypass grafts.

The incidence of perioperative myocardial infarction (MI) was examined in 148 patients with known coronary artery disease (CAD) who underwent 226 noncardiac surgical procedures. In 168 operations in 99 patients who had prior coronary artery bypass grafting (CABG) there were no perioperative MI's whereas in the 49 patients who had not undergone prior CABG who underwent 58 noncardiac operations, there were three MI's (5 percent). The lower (p less than 0.02) incidence of perioperative MI in patients with CAD who had had prior CABG suggests a protective effect for subsequent noncardiac operation, which could not be explained by other differences in cardiac status between the groups. All three MI's occurred in patients with three-vessel CAD, evidence that this should be added to prior MI as a significant risk factor. The study indicates also that patients with prior CABG have less risk of MI during and following anesthesia and noncardiac operation than do patients without CABG who have had a previous MI.     

Impact of dialysis modality on survival of new ESRD patients with congestive heart failure in the United States

BACKGROUND: It is hypothesized, but not proven, that peritoneal dialysis might be the optimal treatment for end-stage renal disease (ESRD) patients with established congestive heart failure (CHF) through better volume regulation compared with hemodialysis. METHODS: National incidence data on 107,922 new ESRD patients from the Center for Medicare and Medicaid Services (CMS) Medical Evidence Form were used to test the hypothesis that peritoneal dialysis was superior to hemodialysis in prolonging survival of patients with CHF. Nonproportional Cox regression models evaluated the relative hazard of death for patients with and without CHF by dialysis modality using primarily the intent-to-treat but also the as-treated approach. Diabetics and nondiabetics were analyzed separately. RESULTS: The overall prevalence of CHF was 33% at ESRD initiation. There were 27,149 deaths (25.2%), 5423 transplants (5%), and 3753 (3.5%) patients lost to follow-up over 2 years. Adjusted mortality risks were significantly higher for patients with CHF treated with peritoneal dialysis than hemodialysis [diabetics, relative risk (RR) = 1.30, 95% confidence interval (CI) 1.20 to 1.41; nondiabetics, RR = 1.24, 95% CI 1.14 to 1.35]. Among patients without CHF, adjusted mortality risk were higher only for diabetic patients treated with peritoneal dialysis compared with hemodialysis (RR = 1.11, 95% CI 1.02 to 1.21) while nondiabetics had similar survival on peritoneal dialysis or hemodialysis (RR = 0.97, 95% CI 0.91 to 1.04). CONCLUSION: New ESRD patients with a clinical history of CHF experienced poorer survival when treated with peritoneal dialysis compared with hemodialysis. These data suggest that peritoneal dialysis may not be the optimal choice for new ESRD patients with CHF perhaps through impaired volume regulation and worsening cardiomyopathy.     

Mortality in end-stage renal disease: a reassessment of differences between patients treated with hemodialysis and peritoneal dialysis

Recent registry studies comparing mortality between peritoneal dialysis (PD) and hemodialysis (HD) patients show conflicting results. The purpose of this study is to determine whether previously published results showing higher mortality for patients treated with PD versus HD in the United States continue to hold true over the period 1987-1993. National mortality rates for PD and HD were extracted from the U.S. Renal Data System (USRDS) annual reports for the cohort periods: 1987-1989, 1988-1990, 1989-1991, 1990-1992, and 1991-1993. Using Poisson regression, death rates per 100 patient years were compared between PD and HD for each cohort period controlling for age, gender, race, and cause of end-stage renal disease (diabetes versus nondiabetes). When incident patients and patients with a prior transplant were included in the analysis, starting with the 1989-1991 cohort, we found little or no difference in the relative risk (RR PD:HD) of death between PD and HD (1987-1989: RR = 1.17, P < 0.001; 1988-1990: RR = 1.12, P < 0.001; 1989-1991: RR = 1.06, P = NS; 1990-1992: RR = 1.06, P = NS; 1991-1993: RR = 1.08, P = 0.043). After a test for goodness-of-fit, separate analyses for diabetic patients and nondiabetic patients were done to examine unexplained variation in death rates. For nondiabetic patients, there was less than a 1% difference in the adjusted 1-yr survival between PD and HD from 1989-1993 (1989-1991: RR = 1.05, P = NS; 1990-1992: RR = 1.04, P = NS; 1991-1993: RR = 1.07, P < 0.01). Among diabetic patients, the PD:HD death rate ratio varied significantly according to gender and age. For the average male diabetic patient, there was little or no difference in risk between PD and HD from 1989-1993 (1989-1991: RR = 1.02, P = NS; 1990-1992: RR = 1.05, P = NS; 1991-1993: RR = 1.08, P < 0.01). For diabetic patients under the age of 50, those treated with PD had a significantly lower risk of death than those treated with HD (1989-1993: 0.84 < or = RR < or = 0.89, P < 0.005). Over the same period, female diabetic patients treated with PD had a higher risk, on average, than HD (1.18 < or = RR < or = 1.19, P < 0.001) as did diabetic patients over the age 50 (1.28 < or = RR < or = 1.30, P < 0.001). Unlike previously published results that were restricted to prevalent-only patients, this national study of both prevalent and incident patients found little or no difference in overall mortality between PD and HD. The recent trends in mortality likely reflect the inclusion of incident patients, but they may also reflect changes in case-mix differences and/or improved PD practice. Additional incident-based studies that allow for additional case-mix adjustments are needed to better compare outcomes between HD and PD.     

Location of acute coronary artery thromboses in patients with and without chronic kidney disease

Patients with chronic kidney disease have high rates of myocardial infarction and death following an initial attack. Proximal location of coronary atherosclerotic lesions has been linked to the risk of acute myocardial infarction and to infarction-associated mortality. To examine if the spatial distribution of lesions differs in patients with and without chronic kidney disease, we used quantitative coronary angiography to measure this in patients with acute coronary thromboses who were having angiography following acute myocardial infarction. Multivariable linear regression was used to adjust for differences in baseline characteristics. Among 82 patients with stage 3 or higher chronic kidney disease, 55.6% of lesions were located within 30 mm and 87.7% were within 50 mm of the coronary ostia. This compared to 34.7 and 71.8%, respectively, among 299 patients without significant kidney disease. Chronic kidney disease was independently and significantly associated with a 7.0 mm decrease in the distance from the coronary ostia to the problem lesion. Our study suggests that a causal link between a more proximal culprit lesion location in patients with chronic kidney disease and their high mortality rates after myocardial infarct is possible and may have important implications for interventions to prevent infarction.     

Sex and gender differences in coronary artery disease

Significant sex differences exist between men and women with regard to coronary artery disease. Most notably, this lethal disease kills more women than men each year and remains the leading cause of death for both men and women. Women and men clearly have different risk profiles when diagnosed with coronary artery disease and fare much differently after myocardial infarction and coronary artery bypass grafting. This review summarizes the sex differences in clinical presentation, diagnosis, and the surgical treatment of coronary artery disease between men and women; and potential multifactorial reasons for sex disparities are suggested.     

Rate of ESRD Exceeds Mortality among African Americans with Hypertensive Nephrosclerosis

In several studies, patients with CKD seemed to be at greater risk for dying from cardiovascular disease (CVD) than reaching ESRD. The purpose of this study was to compare incident ESRD rates with rates of total mortality, CVD death, and a CVD composite (CVD mortality and CVD hospitalization) among participants who had hypertensive nephrosclerosis and were enrolled in the African American Study of Kidney Disease and Hypertension (AASK). The study period included the AASK trial phase (1996 through 2001) and a subsequent cohort phase (2002 through 2007). The AASK enrolled 1094 participants. Of the 764 participants who completed the trial phase without an event, 691 (90%) enrolled in the cohort phase. During 11 years of follow-up, there were 59 CVD-related deaths and 118 non–CVD-related deaths. The rate of ESRD (3.9/100 patient-years) was significantly higher than the rates of total mortality (2.2/100 patient-years), CVD mortality (0.8/100 patient-years), and the CVD composite (3.2/100 patient-years). The incidence rate ratio of ESRD to CVD mortality was 5.0. The rate of ESRD consistently exceeded the various mortality rates across most of the subgroups defined by age, gender, income, education, previous CVD, baseline urine protein excretion, and baseline estimated GFR. In conclusion, AASK participants were more likely to reach ESRD than to die.Cardiovascular disease (CVD) is the leading cause of death for patients with ESRD.¹ In several studies, patients with chronic kidney disease (CKD) seemed to be at greater risk for a CVD death than for reaching ESRD.^2–4 A graded inverse relationship has been observed between estimated GFR (eGFR) and risk for mortality and cardiovascular events in populations with chronic kidney disease (CKD).^5–8Although numerous studies have reported that African American patients have fewer CVD events and lower CVD mortality than white patients in the setting of ESRD, corresponding data in the setting of CKD are sparse and inconsistent.^9–11 Some studies reported increased CVD risk among African American compared with white patients, although the excess risk was eliminated after the adjustment for socioeconomic factors.^12,13 A pooled analysis of patients with CKD from four community-based studies reported a greater risk for a composite of death, nonfatal myocardial infarction (MI), and stroke among African American than among white patients, a result in part of a greater severity of hypertension and/or diabetes in the former.¹² These findings underscore the need for appropriately designed studies to document both CVD and renal events in large, well-characterized populations of African American patients with CKD.The purpose of this report is to compare incident ESRD rates with event rates for total mortality, CVD mortality, and a composite including both CVD mortality and CVD hospitalizations among African American patients with established CKD and well-controlled BP during the course of 11 years of follow-up in the African-American Study of Kidney Disease and Hypertension (AASK).     

Impact of initial dialysis modality and modality switches on Medicare expenditures of end-stage renal disease patients

BACKGROUND: The number of end-stage renal disease (ESRD) enrollees and Medicare expenditures have increased dramatically. Pathways and associated Medicare expenditures in ESRD treatment need to be examined to potentially improve the efficiency of care. METHODS: This study examines the impact of initial dialysis modality choice and subsequent modality switches on Medicare expenditure in a 3-year period. The Dialysis Morbidity and Mortality Study Wave 2 data by the United States Renal Data System (USRDS) is used along with the USRDS Core CD and USRDS claims data. RESULTS: A total of 3423 incident dialysis patients (approximately equal number of peritoneal dialysis and hemodialysis) were included in the analysis. Unadjusted average annual Medicare expenditure (in 2004 dollars) for peritoneal dialysis as first modality was 53,277 dollars(95% CI 50,626 dollars-55,927 dollars), and 72,189 dollars (95% CI 67,513 dollars-76,865 dollars) for hemodialysis. Compared to "hemodialysis, no switch" subgroup, "peritoneal dialysis, no switch" had a significantly lower annual expenditure (44,111 dollars vs. 72,185 dollars) (P < 0.001). "Peritoneal dialysis, with at least one switch" and "hemodialysis, with at least one switch" had a lower or similar annual expenditure of 66,639 dollars and 72,335 dollars, respectively. After adjusting for patient characteristics, annual Medicare expenditure was still significantly lower for patients with peritoneal dialysis as the initial modality (56,807 dollars vs. 68,253 dollars) (P < 0.001). Similarly, compared to "hemdialysis, no switch" subgroup, "peritoneal dialysis, no switch" and "peritoneal dialysis, with at least one switch" had a significantly lower total expenditure. Further analysis showed that time-to-first switch also independently impacted total expenditure. CONCLUSION: Initial modality choice (peritoneal dialysis or hemodialysis) and subsequent modality switches had significant implications for Medicare expenditure on ESRD treatments.     

Limb salvage in end-stage renal disease (ESRD). Comparison of modern results in patients with and without ESRD

We reviewed our experience with femoral-popliteal-tibial reversed vein bypasses performed for limb salvage in 226 patients without and 19 patients with end-stage renal disease (ESRD). While 18-month primary patency rates were comparable (85% and 89%), limb salvage was significantly lower (76% vs 95%) in patients with ESRD. Five amputations in the ESRD group were required for nonhealing, large foot ulcers in diabetic patients despite patent arterial bypass while only five of 13 amputations in patients without ESRD were required in the presence of patent grafts. The need for major amputation despite patent bypass in diabetic patients with ESRD who have extensive foot gangrene or ischemic ulceration occurs sufficiently often that we recommend primary amputation be considered in these patients without regard to possible vascular reconstruction.     

Relationship of body size and initial dialysis modality on subsequent transplantation, mortality and weight gain of ESRD patients

Background Whether peritoneal dialysis (PD) treatment leads to greater weight gain than with hemodialysis (HD) and if this limits access of obese end-stage renal disease patients to renal transplantation has not been examined. We undertook this study to determine the interrelationship between body size and initial dialysis modality on transplantation, mortality and weight gain. Methods Time to transplantation, time to death and weight gain were estimated in a 1:1 propensity score-matched cohort of incident HD and PD patients treated in facilities owned by DaVita Inc. between 1 July 2001 through 30 June 2006 followed through 30 June 2007 (4008 pairs) in four strata of body mass index (BMI) (<18.5, 18.5-24.99, 25.00-29.99 and ≥30 kg/m(2)). Results Transplantation was significantly more likely in PD patients [adjusted hazards ratio (aHR) 1.48, 95% confidence interval (95% CI) 1.29-1.70]; the probability of receiving a kidney transplant was significantly higher in each strata of BMI >18.5 kg/m(2), including with BMI ≥30 kg/m(2) (aHR 1.45, 95% CI 1.11-1.89). PD patients had significantly lower all-cause mortality for patients with BMI 18.50-29.99 kg/m(2). Both these findings were confirmed on analyses of the entire unmatched incident cohort (PD 4008; HD 58 471). The effect of dialysis modality on weight gain was tested in 687 propensity score-matched pairs; the odds of >2, >5 or >10% weight gain were significantly lower in PD patients. Conclusion Treatment with PD is less likely to be associated with a significant weight gain and does not limit the access of obese patients to renal transplantation.     

终末期肾病患者心血管事件与血清胎球蛋白A及冠脉钙化的关系

目的探讨终末期肾病（ESRD）患者心血管事件发生与血清胎球蛋白A及冠脉钙化的关系。方法对38例ESRD初始血液透析患者进行血清胎球蛋白A及相关因素检测，对其中的29例患者进行冠状动脉多层螺旋CT钙化评价研究。所有38例患者随访时间为18个月。22例非ESRD慢性肾脏病（CKDⅡ～Ⅲ期）患者人选对照组。结果38例ESRD初始透析患者在18个月随访期内出现心血管事件30例次，因心血管事件死亡者6例，占15．79％，而非ESRD患者心血管事件仅3例次（P〈0．01）且无一例死亡（P〈0．05）。ESRD血清低胎球蛋白A组心血管事件显著高于ESRD血清高胎球蛋白A组（P〈0．01）。多元逐步回归分析显示，心血管事件与血清胎球蛋白A（P〈0．01）、C反应蛋白（CRP）（P=0．0014）及低密度脂蛋白C（LDL-C）（P=0．008）密切相关。18／29例（62．07％）有冠状动脉钙化。冠状动脉钙化患者心血管事件比无冠状动脉钙化患者显著增多（P〈0．01）。冠脉钙化的ESRD患者血清胎球蛋白A水平较无冠脉钙化的ESRD患者明显下降（P〈0．01）。冠脉钙化与胎球蛋白A下降及高血磷有关（P〈0．01，P〈0．01）。结论ESRD透析患者心血管事件和（或）心血管事件死亡可能与血清胎球蛋白A下降及冠状动脉钙化有关。