Impact of renal transplantation on survival in end-stage renal disease patients with elevated body mass index

BACKGROUND: Cadaveric renal transplantation is associated with a survival advantage compared with dialysis patients remaining on the renal transplantation waiting list, but this advantage has not been confirmed in obese end-stage renal disease (ESRD) patients. METHODS: Using data from the USRDS, we studied 7521 patients who presented with ESRD from 1 April 1995 to 29 June 1999 and later enrolled on the renal transplantation waiting list with body mass indices (BMI) >or=30 kg/m(2) at the time of presentation to ESRD, and followed until 6 November 2000. Recipients of preemptive renal transplantation or organs other than kidneys were excluded. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for time to death in a given patient during the study period, controlling for renal transplantation, demographics and comorbidities (Form 2728). RESULTS: The incidence of mortality was 3.3 episodes per 100 patient-years (PY) in cadaveric renal transplantation and 1.9/100 PY in living donor renal transplantation compared with 6.6 episodes/100 PY in all patients on the transplant waiting list. In comparison to maintenance dialysis, both recipients of solitary cadaveric kidneys (HR 0.39, 95% CI 0.33 to 0.47), and recipients of living donor kidneys (HR 0.23, 95% CI 0.16 to 0.34) had statistically significant improved survival. A benefit of cadaveric renal transplantation did not apply to patients with BMI >or=41 kg/m(2) (HR 0.47, 95% CI, 0.17 to 1.25, P = 0.13). CONCLUSIONS: Obese patients on the renal transplant waiting list had a significantly lower risk of mortality after renal transplantation compared with those remaining on dialysis.     

Survival improvement among patients with end-stage renal disease: trends over time for transplant recipients and wait-listed patients

Both transplant and dialysis outcomes have improved over recent years. In addition, transplantation has been shown to confer a survival benefit over maintenance dialysis. The study presented here addresses the question of whether the survival benefit of transplantation over maintenance dialysis has changed in the most recent eras. This study was based on data collected by the United States Renal Transplant Scientific Registry and the United States Renal Data System. The study sample consisted of 104,000 patients placed on the renal transplant waiting list between 1988 and 1996, of which 73,707 subsequently received renal transplants. The annualized adjusted mortality rates per 1000 patient-years were calculated by calendar year of placement on the renal transplant waiting list and for kidney transplant recipients. The resulting data were plotted, and linear curve fitting was used to estimate the slope of the change of the adjusted mortality rates by year during the period studied, 1988 to 1996. Overall annual adjusted death rates in the wait-listed patients and transplant recipients per 1000 patient-years decreased for both groups throughout the study period. From 1989 to 1996, the relative risk (RR) for patient death had decreased by 30% for transplant recipients and 23% for wait-listed patients (RR = 0.70 and 0.77; P < 0.0001 each). Slope analysis of the cause-specific mortality rates for cardiovascular disease and infection showed nearly equivalent, linear decreases for both groups. Mortality rates have improved overall and by categories of major cause of death for both renal transplant recipients and patients on the renal transplant waiting list. These favorable trends most likely represent equal advances in transplantation, dialysis, and general medical care.     

Current incidence, treatment patterns and outcome of end-stage renal disease among indigenous groups in Australia and New Zealand

SUMMARY: The changes in rates of treated end-stage renal disease (ESRD) among indigenous populations have profound consequences for those individuals affected and for health-care providers. By using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry, we examined the current incidence, treatment and outcomes of ESRD among indigenous groups in Australia and New Zealand. All patients who began renal replacement therapy (RRT) in Australia or New Zealand between October 1991 and September 2000 were included. Rates of ESRD, RRT modalities, renal transplantation and mortality were the outcomes examined. End-stage renal disease rates among indigenous groups in Australia and New Zealand exceeded non-indigenous rates up to eightfold. The median age of indigenous ESRD patients was younger (51 vs 60 years, P  < 0.0001), and there was an excess of comorbidities, particularly diabetes. For Australian Aboriginal and Torres Strait Islanders, and New Zealand Maori patients, mortality rates across all modalities of RRT were 70% higher than non-indigenous rates. Indigenous people were less likely to receive a renal transplant prior to dialysis treatment, less likely to be accepted onto the cadaveric transplant waiting list, and less likely to receive a well-matched transplant. The poorer outcomes among Australian Aboriginal and Torres Strait Islanders, and New Zealand Maori patients did not appear to be explained by the different comorbid conditions or age. Whether the outcomes reflect unmeasured differences in disease burden or treatment differences is not known. Tackling this problem will involve a spectrum of people and approaches, from tertiary care providers and RRT to local staff and preventative programs.     

A comparison of the effects of dialysis and renal transplantation on the survival of older uremic patients

BACKGROUND: Patients over age 60 constitute half of all new patients accepted into the renal replacement therapy programs in Australia. However, the optimal treatment of their end-stage renal disease remains controversial. The aim of the present study was to compare survival for dialysis and renal transplantation in older patients who were rigorously screened and considered eligible for transplantation. METHODS: The study cohort consisted of 174 consecutive patients over 60 who were accepted on to the Queensland cadaveric renal transplant waiting list between January 1, 1993 and December 31, 1997. Follow-up was terminated on October 1, 1998. Data were analyzed on an intention-to-transplant basis using a Cox regression model with time-varying explanatory variables. An alternative survival analysis was also performed, in which patients no longer considered suitable for transplantation were censored at the time of their removal from the waiting list. RESULTS: There were 67 patients receiving a renal transplant, whereas the other 107 continued to undergo dialysis. These two groups were well matched at baseline with respect to age, gender, body mass index, renal disease etiology, comorbid illnesses, and dialysis duration and modality. The overall mortality rate was 0.096 per patient-year (0.131 for dialysis and 0.029 for transplant, P<0.001). Respective 1-, 3- and 5-year survivals were 92%, 62%, and 27% for the dialysis group and 98%, 95%, and 90% (P<0.01) for the transplant group. Patients in the transplant group had an adjusted hazard ratio 0.16 times that of the dialysis group (95% confidence interval 0.06-0.42). If patients were censored at the time of their withdrawal from the transplant waiting list, the adjusted hazard ratio was 0.24 (95% confidence interval 0.09-0.69). CONCLUSIONS: Renal transplantation seems to confer a substantial survival advantage over dialysis in patients with end-stage renal failure who are rigorously screened and considered suitable for renal transplantation.     

The impact of simultaneous pancreas-kidney transplantation on long-term patient survival

BACKGROUND: Simultaneous pancreas-kidney transplantation (SPK) ameliorates the progression of microvascular diabetic complications but the procedure is associated with excess initial morbidity and an uncertain effect on patient survival when compared with solitary cadaveric or living donor renal transplantation. We evaluated mortality risks associated with SPK, solitary renal transplantation, and dialysis treatment in a national cohort of type 1 diabetics with end-stage nephropathy. METHODS: A total of 13,467 adult-type 1 diabetics enrolled on the renal and renal-pancreas transplant waiting list between 10/01/88 and 06/30/97 were followed until 06/30/98. Time-dependent mortality risks and life expectancy were calculated according to the treatment received subsequent to wait-list registration: SPK; cadaveric kidney only (CAD); living donor kidney only (LKD) transplantation; and dialysis [wait-listed, maintenance dialysis treatment (WLD)]. RESULTS: Adjusted 10-year patient survival was 67% for SPK vs. 65% for LKD recipients (P=0.19) and 46% for CAD recipients (P<0.001). The excess initial mortality normally associated with renal transplantation and the risk of early infectious death was 2-fold higher in SPK recipients. The time to achieve equal proportion of survivors as the WLD patients was 170, 95, and 72 days for SPK, CAD, and LKD recipients, respectively (P<0.001). However, the adjusted 5-year morality risk (RR) using WLD as the reference and the expected remaining life years were 0.40, 0.45, and 0.75 and 23.4, 20.9, and 12.6 years for SPK, LKD, and CAD, respectively. There was no survival benefit in SPK recipients > or =50 years old (RR=1.38, P=0.81). CONCLUSIONS: Among patients with type 1 DM with end-stage nephropathy, SPK transplantation before the age of 50 years was associated with long-term improvement in survival compared to solitary cadaveric renal transplantation or dialysis.     

Burden of end-stage renal disease among indigenous peoples in Australia and New Zealand

Rates of end-stage renal disease (ESRD) among indigenous people in Australia and New Zealand are considerably higher than the non-indigenous population. This trend, apparent for several years, is described here using data from the Australia & New Zealand Dialysis and Transplant (ANZDATA) Registry. The average age at start of renal replacement therapy (RRT) is approximately 10 years less than non-indigenous people. Among those starting RRT, rates of "diabetic nephropathy" are higher among indigenous patients, reflecting higher rates of diabetes. The increased burden of illness extends to coronary artery disease and chronic lung disease, which are present at rates 1.5 to 2 times non-indigenous rates. Once dialysis treatment has commenced, indigenous people are less likely to be placed on the active cadaveric transplant waiting list, and less likely to receive a graft. Overall mortality outcomes are poorer for indigenous patients overall, and for each RRT modality. These outcomes are not simply due to increased frequency of co-morbid illness: for indigenous people receiving dialysis treatment the mortality rate adjusted for age and gender is around 11/2 times the non-indigenous rate. These data are consistent with studies showing increased rates of markers of early renal disease (in particular albuminuria) among both Australian and New Zealand indigenous groups, and reflect a broader health profile marked by high rates of diabetes, cardiovascular disease and chronic lung disease. Addressing these issues is a major challenge for health care providers in these regions.     

Hospitalizations for bacterial septicemia in patients with end stage renal disease due to diabetes on the renal transplant waiting list

The incidence and risk factors for hospitalizations for bacterial septicemia, a serious cause of morbidity and mortality in end stage renal disease (ESRD), have been studied separately for patients on chronic dialysis and after renal transplantation, but have not been compared directly. Using data from the USRDS, we studied 11,369 patients with ESRD due to diabetes enrolled on the renal and renal-pancreas transplant waiting list from 1 July 1994-30 June 1997. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for time to hospitalization for bacterial septicemia (ICD9 Code 038.x). In Cox Regression analysis, renal transplantation was independently associated with a shorter time to bacterial septicemia (HR 1.22, 95% confidence interval, 1.05-1.40). In addition, renal transplantation was associated with a higher rate of sepsis due to gram-negative organisms (HR 3.32, 95% CI 2.614.23) and urinary tract infection (10.43, 95% CI 6.72-16.17) compared with patients still on the renal transplant waiting list. The relative risk of sepsis increased with time after renal transplantation. Renal transplantation was associated with a significantly higher risk and different spectrum of bacterial septicemia than maintenance dialysis, and the risk of sepsis did not decrease over time.     

Survival Benefit From Kidney Transplantation Using Kidneys From Deceased Donors Aged ≥75 Years: A Time‐Dependent Analysis

Patients with end‐stage renal disease have longer survival after kidney transplantation than they would by remaining on dialysis; however, outcome with kidneys from donors aged ≥75 years and the survival of recipients of these organs compared with their dialysis counterparts with the same probability of obtaining an organ is unknown. In a longitudinal mortality study, 2040 patients on dialysis were placed on a waiting list, and 389 of them received a first transplant from a deceased donor aged ≥75 years. The adjusted risk of death and survival were calculated by non–proportional hazards analysis with being transplanted as a time‐dependent effect. Projected years of life since placement on the waiting list was almost twofold higher for transplanted patients. Nonproportional adjusted risk of death after transplantation was 0.44 (95% confidence interval [CI] 0.61–0.32; p < 0.001) in comparison with those that remained on dialysis. Stratifying by age, adjusted hazard ratios for death were 0.17 (95% CI 0.47–0.06; p = 0.001) for those aged <65 years, 0.56 (95% CI 0.92–0.34; p = 0.022) for those aged 65–69 years and 0.82 (95% CI 1.28–0.52; p = 0.389) for those aged ≥70 years. Although kidney transplantation from elderly deceased donors is associated with reduced graft survival, transplanted patients have lower mortality than those remaining on dialysis.     

Waiting time on dialysis as the strongest modifiable risk factor for renal transplant outcomes: a paired donor kidney analysis

BACKGROUND: Waiting time on dialysis has been shown to be associated with worse outcomes after living and cadaveric transplantation. To validate and quantify end-stage renal disease (ESRD) time as an independent risk factor for kidney transplantation, we compared the outcome of paired donor kidneys, destined to patients who had ESRD more than 2 years compared to patients who had ESRD less than 6 months. METHODS: We analyzed data available from the U.S. Renal Data System database between 1988 and 1998 by Kaplan-Meier estimates and Cox proportional hazards models to quantify the effect of ESRD time on paired cadaveric kidneys and on all cadaveric kidneys compared to living-donated kidneys. RESULTS: Five- and 10-year unadjusted graft survival rates were significantly worse in paired kidney recipients who had undergone more than 24 months of dialysis (58% and 29%, respectively) compared to paired kidney recipients who had undergone less than 6 months of dialysis (78% and 63%, respectively; P<0.001 each). Ten-year overall adjusted graft survival for cadaveric transplants was 69% for preemptive transplants versus 39% for transplants after 24 months on dialysis. For living transplants, 10-year overall adjusted graft survival was 75% for preemptive transplants versus 49% for transplants after 24 month on dialysis. CONCLUSIONS: ESRD time is arguably the strongest independent modifiable risk factor for renal transplant outcomes. Part of the advantage of living-donor versus cadaveric-donor transplantation may be explained by waiting time. This effect is dominant enough that a cadaveric renal transplant recipient with an ESRD time less than 6 months has the equivalent graft survival of living donor transplant recipients who wait on dialysis for more than 2 years.     

Cardiac troponin levels in asymptomatic patients on the renal transplant waiting list

AIMS: Cardiac troponin levels predict mortality and cardiovascular events in asymptomatic patients receiving dialysis and may be a useful clinical tool to stratify high-risk asymptomatic individuals. METHODS: The present study examined levels of troponins I (cTnI) and T (cTnT) in patients with chronic renal impairment, patients receiving dialysis and renal transplant recipients. Patients receiving dialysis on the renal transplant waiting list were compared with those excluded from the list based on medical criteria. Median levels were compared using the Kruskal-Wallis test and proportions compared by chi-squared. RESULTS: Median troponin levels were higher in patients on dialysis than transplant recipients. Comparing patients receiving dialysis not listed compared with those listed for renal transplant, median cTnI levels were significantly higher (0.03 versus 0.02 microg/L, P < 0.01) whereas median cTnT levels were not. Patients listed for transplantation were younger, had less clinical cardiovascular disease and lower C-reactive protein than those awaiting renal transplantation. The proportion of patients with elevated cTnT was not substantially different between patients awaiting renal transplantation (38%) and those excluded (52%). Levels of cTnI and cTnT were inversely related to renal function in predialysis and transplant patients, but were not related to time on dialysis for those receiving dialysis therapy. CONCLUSION: As patients awaiting renal transplantation are clinically screened for cardiovascular disease but have frequently elevated cardiac troponin levels, troponin may be a useful clinical tool to identify high-risk asymptomatic patients on dialysis prior to renal transplantation. The influence of renal function on the interpretation of cardiac troponin and risk prediction requires further evaluation.     

Renal transplantation in elderly patients older than 70 years of age: results from the Scientific Registry of Transplant Recipients

BACKGROUND: Elderly patients (ages 70 yr and older) are among the fastest-growing group starting renal-replacement therapy in the United States. The outcomes of elderly patients who receive a kidney transplant have not been well studied compared with those of their peers on the waiting list. METHODS: Using the Scientific Registry of Transplant Recipients, we analyzed data from 5667 elderly renal transplant candidates who initially were wait-listed from January 1, 1990 to December 31, 2004. Of these candidates, 2078 received a deceased donor transplant, and 360 received a living donor transplant by 31 December 2005. Time-to-death was studied using Cox regression models with transplant as a time-dependent covariate. Mortality hazard ratios (RRs) of transplant versus waiting list were adjusted for recipient age, sex, race, ethnicity, blood type, panel reactive antibody, year of placement on the waiting list, dialysis modality, comorbidities, donation service area, and time from first dialysis to first placement on the waiting list. RESULTS: Elderly transplant recipients had a 41% lower overall risk of death compared with wait-listed candidates (RR=0.59; P<0.0001). Recipients of nonstandard, that is, expanded criteria donor, kidneys also had a significantly lower mortality risk (RR=0.75; P<0.0001). Elderly patients with diabetes and those with hypertension as a cause of end-stage renal disease also experienced a large benefit. CONCLUSIONS: Transplantation offers a significant reduction in mortality compared with dialysis in the wait-listed elderly population with end-stage renal disease.     

Prevalence of cancer history prior to renal transplantation

Recurrent and de novo cancers contribute to morbidity and mortality post-transplantation. However, data on cancer prevalence in waiting list patients are lacking. The purpose of this study was to determine the prevalence of malignancy in patients considered for renal transplantation. Records of 382 potential renal transplant recipients were reviewed for the presence of malignant tumours. In 38 patients 45 tumours were detected. Forty-two malignancies were histologically confirmed, in three patients the evaluation was ongoing. Fourteen tumours were diagnosed before and 31 after initiation of dialysis. Overall cancer prevalence was 9.9%. For patients in the waiting list, the mean time from diagnosis of the malignancy was 2.2 years. Twenty of 45 (44%) tumours were located in the urinary system. The majority of malignancies was treated with a curative intention. Thus, 68% of patients with malignancies were listed as 'transplantable' or 'temporarily not transplantable'. From the waiting list, 13% were removed , 8% died and 11% had their evaluation halted because of their malignancy. Four patients received a transplant while eight patients died or were removed permanently from the list prior to transplantation. Death or removal from the list was as frequently related to tumour progression as to other causes (four patients each). A substantial number of waiting list patients had a history of malignancy. Future strategies have to identify patients at risk to assure intensive monitoring for recurrence, selection of patients who do not benefit from deferred transplantation and consideration of specific immunosuppressive protocols.     

Survival in recipients of marginal cadaveric donor kidneys compared with other recipients and wait-listed transplant candidates

An increasing number of cadaveric kidney transplants are now performed with organs from donors who would have been deemed unsuitable in earlier times. Although good allograft outcomes have been obtained with these marginal donor transplants, it is unclear whether recipients of marginal kidney transplants achieve a reduction in long-term mortality as do recipients of "ideal" kidneys. Patients with end-stage renal disease registered on the cadaveric renal transplant waiting list between January 1, 1992, and June 30, 1997, were studied for mortality risks according to three outcomes: wait-listed on dialysis treatment with no transplant (WLD); transplantation with marginal donor kidney (MDK); and "ideal" or optimal donor kidney transplantation (IDK). Thirty-four percent of wait-list registrants had received a cadaveric kidney transplant by June 30, 1998. Of these, 18% received a marginal kidney that had one or more of the following pretransplant factors: donor age >55 yr, non-heartbeating donor, cold ischemia time >36 h, and donor hypertension or diabetes mellitus of > 10 yr duration. Five-year graft and patient survival was 53% and 74% for MDK recipients compared with 67% (P< 0.001) and 80% (P< 0.001) for IDK recipients. Adjusted annual death rate and estimated remaining life time was 6.3%, 4.7%, and 3.3% and 15.3 yr, 20.4 yr, and 28.7 yr for WLD, MDK, and IDK groups, respectively. The average increase in life expectancy for MDK recipients compared with the WLD cohort was 5 yr, although this benefit varied from 3 to 10 yr depending on the recipient's characteristics. It is concluded that transplantation of a marginal kidney is associated with a significant survival benefit when compared with maintenance dialysis.     

Geographic variance in access to renal transplantation in Australia

BACKGROUND: Geographic disparities in access to transplantation in Australia during the past 15 years have been accentuated by the increasing size of the transplant waiting lists in each state and by low cadaveric donation rates. Access to dialysis treatment is similar in all states of Australia, although there are fewer elderly dialysis patients in South Australia. RESULTS: Access to the transplant waiting list varies significantly between the states, with one state having 39 per million population (pmp) on their list compared with the two most populous states at 113 pmp and 101 pmp. Patients between the ages of 25 and 54 years in one state had twice the chance of being on the waiting list compared with another.Transplantation rates reflect both the cadaveric donor rate (16.9 transplants pmp) and the large contribution from living donors (39% of all transplants in 2001). Transplantation with a kidney in Australia is dependent both upon age and the state of residence, with one state performing transplantations with 15% of their dialysis population each year but all other states achieving less than 10%, with an average of 8% for the country as a whole. CONCLUSIONS: Criteria for access to the transplantation waiting list in each state vary, depending perhaps upon whether a general community or individual patient perspective is the dominant policy. Access to transplantation on the other hand is reflective of each states' cadaveric donation rate modified by increasing use of living donors, especially in younger patients.     

Patient survival after renal transplantation; more than 25 years follow-up

Background: The determinators of patient survival after renal transplantation are incompletely known, and conflicting results hae been reported. This may have been influenced by time-related changes in patients selection, post-transplantation management and immunosuppressive regimens. This study was performed to evaluate in recipients of a first renal transplant the effect of patient characteristics, transplantation era, and the immunosuppressive regimen on patient survival. Method: We studied data from the Leiden Renal Transplant Database of all first renal transplantations performed between 1966 and 1994 in Leiden, the Netherlands. The effect of the following parameters on mortality was investigated: era of transplantation, sex, age at transplantation, cause of renal failure, immunosuppressive regimen, type and duration of pretransplantation dialysis, hypertension, diabetes mellitus, and smoking. In addition we analysed the causes of death. Results were expressed as crude mortality rates, relative risks of mortality, and standardized mortality ratios as compared with death rates in the Dutch population. Results: The analysis comprised 86 living donor transplant recipients and 916 cadaver transplant recipients. After adjustment for age and sex, the relative risk of morality for living donor transplant recipients compared with cadaver transplant recipients was 0.5 (95% CI 0.2 to 10.3, P=0.06). In the first cadaver kidney transplant recipients the risk of first-year mortality improved significantly with time, which coincided with the introduction of cyclosporin. The risk of mortality after the first year was higher in patients aged over 40 years at transplantation, men, smokers, and in the presence of hypertension or diabetes, but the effect of individual factors on mortality was small. We found no effect of the type of pretransplantation dialysis or the duration of pretransplantation haemodialysis on post-transplantation mortality. The standardized mortality ratio for recipients of first renal transplants was 14 times the population average in the first year after transplantation and was still four times in the remaining years. Conclusion: In the present study, time-related changes in patient management were responsible for improved patient survival in the first year after transplantation during the study period. Many individual factors contributed moderately to the risk of mortality after the first year. Compared to the general population the mortality rate of renal transplant recipients was significantly higher during the whole follow-up period.     

Comparison of mortality risk for dialysis patients and cadaveric first renal transplant recipients in Ontario, Canada

In population-based studies, renal transplantation has been shown to improve survival compared to dialysis patients awaiting transplantation in the United States. However, dialysis mortality in the United States is higher than in Canada. Whether transplantation offers a survival advantage in regions where dialysis survival is superior to that in the United States is uncertain. This study examines a cohort of 1156 patients who started end-stage renal disease (ESRD) therapy and were wait-listed for cadaveric renal transplantation in the province of Ontario, Canada between January 1, 1990 and December 31, 1994. Patients were followed from wait-listing for renal transplant (n = 1156), to cadaveric first renal transplant (n = 722), to death, or to study end (December 31, 1995). The annual crude mortality rates for wait-listed dialysis patients and transplanted patients were 5.0 and 3.4%, respectively. In Cox proportional hazards models, mortality in wait-listed patients was associated with increased age and diabetes, but not time from onset of ESRD to wait-listing. Factors associated with death following transplantation include older age, diabetes, and longer time spent on the waiting list before transplantation. In a time-dependent Cox regression model, the relative risk of death after transplantation compared to dialysis varied in a time-dependent manner. Covariates associated with increased risk included older age, diabetes, and time from onset of ESRD to wait-listing. The average relative risk (RR) of dying was 2.91 (95% confidence interval [CI], 1.34 to 6.32) in the first 30 d after transplantation, but was significantly lower 1 yr after transplantation (RR 0.25; 95% CI, 0.14 to 0.42), indicating a beneficial long-term effect when compared to wait-listed dialysis patients. This long-term benefit was most evident in subgroups of patients with diabetes (RR 0.38; 95% CI, 0.17 to 0.87) and glomerulonephritis (RR 0.13; 95% CI, 0.04 to 0.39) as the cause of ESRD. The survival advantage associated with renal transplantation is evident in this cohort of patients with a lower wait-listed dialysis mortality than that reported previously in the United States. The magnitude of the treatment effect is consistent across studies.     

Modifiable factors predicting patient survival in elderly kidney transplant recipients

BACKGROUND: Elderly transplant candidates represent an increasingly important group on the waiting list for kidney transplantation. Yet the factors that determine posttransplantation outcomes in this population remain poorly defined. METHODS: We performed a population-based retrospective cohort study involving all patients aged 60 years or older who received a first cadaveric kidney transplantation between 1985 and 2000 in the province of Quebec. The main outcomes were patient survival, overall graft survival, and treatment failure (patient death or graft loss within the first posttransplant year). Survival analyses were performed using a Cox proportional hazard model. Logistic regression identified factors predicting treatment failure. RESULTS: On multivariate analysis, the modifiable factors associated with patient survival were active smoking at transplantation [hazard ratio (HR) 2.09, 95% confidence interval (CI) 1.22-3.60)], body mass index (BMI) (HR 1.34 for a 5-point increase, 95% CI 1.05-1.67), and time on dialysis before transplantation (HR 1.10 for a 1-year increase, 95% CI 1.02-1.18). The only modifiable factor associated with graft survival was active smoking at transplantation (HR 2.04, 95% CI 1.24-3.30). Treatment failure was associated with time on dialysis before transplantation (odds ratio for dialysis >/=2 years 3.28, 95% CI 1.34-7.9). CONCLUSION: Our results show that active smoking, obesity, and time on dialysis before transplantation are modifiable risk factors associated with an increased risk of mortality after transplantation in elderly recipients. They represent potential targets for interventions aimed at improving patient and graft survival in elderly patients.     

Impact of cadaveric renal transplantation on survival in patients listed for transplantation

The aim of this study was to assess the magnitude of the survival benefit of renal transplantation compared with dialysis in patients selected for transplantation in Scotland. Longitudinal study of survival and mortality risk in all adult patients (1732) listed for a first transplant between January 1, 1989, and December 31, 1989, in Scotland. A time-dependent Cox regression analysis adjusted for comorbidity, sociodemographic and geographic factors, primary renal disease, time on dialysis, and year of listing compared the risk of death for patients receiving a first cadaveric transplant versus all patients on dialysis listed for transplantation. After adjustment for the covariates, the relative risk (RR) of death during the first 30 days after transplantation was 1.35 (95% confidence interval [CI], 0.63 to 2.86) compared with patients on dialysis (RR = 1). The long-term RR (at 18 mo) for the transplant recipients was 0.18 (95% CI, 0.08 to 0.42) when compared with patients on dialysis (RR = 1). This lower long-term risk of death was present in all patients undergoing transplantation, irrespective of their age group or primary renal disease. Similar results were seen when survival with a transplant was censored for graft failure. The projected life expectancy with a transplant was 17.19 yr compared with only 5.84 yr on dialysis. Despite an initial higher risk of death, long-term survival for patients who undergo transplantation is significantly better compared with patients who are listed but remain on dialysis. A successful transplant triples the life expectancy of a listed renal failure patient.     

The impact of renal transplantation on the incidence of congestive heart failure in patients with end-stage renal disease due to diabetes.

BACKGROUND: Patients with end stage renal disease (ESRD) are at increased risk for cardiovascular disease. We hypothesized that the clinical incidence of congestive heart failure (CHF) would be lessened after successful renal transplantation, as many of the metabolic and intravascular volume abnormalities associated with dialysis-dependent ESRD would resolve. METHODS: Using data from the USRDS, we studied 11,369 patients with ESRD due to diabetes enrolled on the renal and renal-pancreas transplant waiting list from 1 July 1994-30 June 1997. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for time to the most recent hospitalization for CHF (including acute myocardial infarction, unstable angina, or other CHF, ICD9 Code 428.x) for a given patient in the study period, controlling for both demographics and comorbidities in the medical evidence form (HCFA 2728). RESULTS: In comparison to maintenance dialysis, renal transplantation was independently associated with a lower risk for CHF (HR 0.64, 95% confidence interval, 0.54-0.77) in a model including age, gender, race, and year of first dialysis, but not in a model including comorbidities from the medical evidence form, although the sample was much smaller. CONCLUSIONS: Patients with ESRD due to diabetes on the renal transplant waiting list were much less likely to be hospitalized for congestive heart failure after renal transplantation, despite post transplant complications due to immunosuppression.     

Effect of body mass index on the survival benefit of liver transplantation.

Obese patients are at higher risk for morbidity and mortality after liver transplantation (LT) than nonobese recipients. However, there are no reports assessing the survival benefit of LT according to recipient body mass index (BMI). A retrospective cohort of liver transplant candidates who were initially wait-listed between September 2001 and December 2004 was identified in the Scientific Registry of Transplant Recipients database. Adjusted Cox regression models were fitted to assess the association between BMI and liver transplant survival benefit (posttransplantation vs. waiting list mortality). During the study period, 25,647 patients were placed on the waiting list. Of these, 4,488 (17%) underwent LT by December 31, 2004. At wait-listing and transplantation, similar proportions were morbidly obese (BMI>or=40; 3.8% vs. 3.4%, respectively) and underweight (BMI<20; 4.5% vs. 4.0%, respectively). Underweight patients experienced a significantly higher covariate-adjusted risk of death on the waiting list (hazard ratio [HR]=1.61; P<0.0001) compared to normal weight candidates (BMI 20 to <25), but underweight recipients had a similar risk of posttransplantation death (HR=1.28; P=0.15) compared to recipients of normal weight. In conclusion, compared to patients on the waiting list with a similar BMI, all subgroups of liver transplant recipients demonstrated a significant (P<0.0001) survival benefit, including morbidly obese and underweight recipients. Our results suggest that high or low recipient BMI should not be a contraindication for LT.