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Arthur J Matas

Publications and source records attributed to Arthur J Matas.

At least 37 records · Page 2Linked to original sources
PubMed2003

Predicting long-term kidney graft survival: can new trials be performed?

BACKGROUND: As short-term transplant results improve, it has become difficult to use patient or graft survival or acute rejection as clinical trial endpoints, except in large, multicenter studies. Despite better outcomes, graft failure continues over time. METHODS: We studied 6- and 12-month creatinine (Cr) level and change in creatinine (deltaCr) level (3-12 months, 6-12 months) as predictors of graft survival for 1,389 primary kidney transplants (minimum graft survival 1 year). Determining the prognostic value of Cr level (6 or 12 months), the subgroups were as follows: less than 1, 1 to 1.4, 1.5 to 1.9, 2.0 to 2.4, 2.5 to 2.9, and greater than or equal to 3 mg/dL. For deltaCr level, the subgroups were as follows: less than 0, 0, 0.01 to 0.2, and greater than 0.2. Subgroup actuarial graft survival was determined. Cox regression analyses were performed with forward, stepwise selection. RESULTS: After 12-month Cr level entered the model, no other variable was significant. Repeating this with continuous variables, 12-month Cr level was again the best predictor. Five-year graft survival for 12-month Cr level less than 1 (n=38) was 95%; for 1.0 to 1.4 (n=454), 87%; for 1.5 to 1.9 (n=463), 86%; for 2.0 to 2.4 (n=166), 78%; for 2.5 to 2.9 (n=54), 60%; for greater than or equal to 3 (n=45), 41%. A major breakpoint for outcome is 1-year Cr level=2.0. A power analysis was performed for the combined endpoint of graft loss and 1-year Cr level greater than 2, reached by 30% of patients. To avoid missing a reduction to 20% (actual decrease 33%) (alpha=0.05; power=0.8), 313 patients would be required per group. For a reduction to 15% (actual decrease 50%), 133 patients would be required. CONCLUSIONS: Twelve-month Cr level is an accurate surrogate for long-term outcome. The use of a combined endpoint (graft loss and 12-month Cr level) allows trials to be performed without exorbitant numbers.

Azathioprine↗
PubMed2003

Positive remote crossmatch: impact on short-term and long-term outcome in cadaver renal transplantation.

BACKGROUND: A positive crossmatch with a "current" recipient serum (drawn shortly before the proposed transplant) is a contraindication to renal transplantation because of the risk of hyperacute rejection. Conflicting data have been reported concerning the significance of a positive crossmatch with "remote" sera (obtained months or years earlier) when the current crossmatch is negative. METHODS: Recipients of a first or second cadaver transplant between June 1988 and April 1994 were studied. All transplants were performed with a negative "current" crossmatch. Retrospective crossmatches using "remote" sera were performed for all sensitized recipients. RESULTS: Recipients with a positive remote crossmatch (RXM) demonstrated a higher incidence of delayed graft function and of acute rejection and graft loss occurring in the first year posttransplant than did sensitized recipients with a negative RXM or unsensitized recipients. In multivariate analysis, only recipients with both a positive RXM and delayed graft function were at significantly higher risk for graft loss. Grafts surviving the first year demonstrated similar half-lives whether the RXM was positive or negative. CONCLUSIONS: The positive RXM, possibly in conjunction with other factors leading to very early graft damage, is a significant predictor of unfavorable transplant outcome in first and second renal transplants. This effect is seen early in the transplant course, and there seems to be no impact on outcome after the first year. Newer immunosuppressive modalities may help to reduce the early negative impact.

Acute Disease↗
PubMed2003

Determinants of quality of life changes among long-term cardiac transplant survivors: results from longitudinal data.

BACKGROUND: Cross-sectional analyses have identified significant associations between quality of life (QOL), and comorbidities and adverse effects in cardiac transplant recipients. However, little is known about factors that influence changes in QOL over time. This study examines both cross-sectional and longitudinal data from long-term survivors to identify factors that affect differences in QOL among recipients and individual changes in QOL during a 1-year period. METHODS: Self-selected enrollees completed questionnaires, including QOL scales, at 3-month intervals. Repeated measures multiple regression analysis was used to examine the association between the QOL scales and comorbidities, adverse effects, and compliance measures, controlling for other factors. RESULTS: We included 569 participants in the analysis, with a mean time since transplantation of 8.6 years. Cross-sectional results showed that the number of comorbidities, treatment non-compliance, and several adverse effects were associated with low QOL. In longitudinal results, waiting to take medications and taking less medication because of lifestyle restrictions were associated with decreases in QOL over time. Hair loss, changes in face shape, and decreased sexual interest or ability also had the largest adverse effects on changes in QOL. CONCLUSIONS: These findings provide new opportunities for interventions to address factors related to decreases in QOL. Clinicians should actively solicit information about compliance with medication regimens. In addition, information about the adverse effects of medications should be considered when making therapeutic decisions.

Adult↗
PubMed2003

Diabetes mellitus after kidney transplantation in the United States.

New onset diabetes is a major complication after kidney transplantation. However, the incidence, risk factors and clinical relevance of post-transplant diabetes mellitus (PTDM) vary among reports from single-center observational studies and clinical trials. Using data from the United Renal Data System we identified 11 659 Medicare beneficiaries who received their first kidney transplant in 1996-2000. The cumulative incidence of PTDM was 9.1% (95% confidence interval = 8.6-9.7%), 16.0% (15.3-16.7%), and 24.0% (23.1-24.9%) at 3, 12, and 36 months post-transplant, respectively. Using Cox's proportional hazards analysis, risk factors for PTDM included age, African American race (relative risk = 1.68, range: 1.52-1.85, p < 0.0001), Hispanic ethnicity (1.35, range: 1.19-1.54, p < 0.0001), male donor (1.12, range: 1.03-1.21, p = 0.0090), increasing HLA mismatches, hepatitis C infection (1.33, range: 1.15-1.55, p < 0.0001), body mass index >or=30 kg/m2 (1.73, range: 1.57-1.90, p < 0.0001), and the use of tacrolimus as the initial maintenance immunosuppressive medication (1.53, range: 1.29-1.81, p < 0.0001). Factors that reduced the risk for PTDM included the use of mycophenolate mofetil, azathioprine, younger recipient age, glomerulonephritis as a cause of kidney failure, and a college education. As a time-dependent covariate in Cox analyses that also included multiple other risk factors, PTDM was associated with increased graft failure (1.63, 1.46-1.84, p < 0.0001), death-censored graft failure (1.46, 1.25-1.70, p < 0.0001), and mortality (1.87, 1.60-2.18, p < 0.0001). We conclude that high incidences of PTDM are associated with the type of initial maintenance immunosuppression, race, ethnicity, obesity and hepatitis C infection. It is a strong, independent predictor of graft failure and mortality. Efforts should be made to minimize the risk of this important complication.

Adolescent↗
PubMed2003

Improved scoring system to assess adult donors for cadaver renal transplantation.

We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation.

Adult↗
PubMed2003

Morbidity and mortality after living kidney donation, 1999-2001: survey of United States transplant centers.

There have been two recent trends in living kidney donation: increased acceptance of living donors and increased acceptance of laparoscopic nephrectomy (LN). We surveyed 234 UNOS-listed kidney transplant programs to determine current living donor morbidity and mortality for open nephrectomy, hand-assisted LN, and non-hand-assisted LN. Of the 234 centers, 171 (73%) responded. Between 1/1/1999 and 7/1/2001, these centers carried out 10 828 living donor nephrectomies: 52.3% open, 20.7% hand-assisted LN, and 27% non-hand-assisted LN. Two donors (0.02%) died from surgical complications and one is in a persistent vegetative state (all after LN). Reoperation was necessary in 22 (0.4%) open, 23 (1.0%) hand-assisted LN, and 21 (0.9%) non-hand-assisted LN cases (p = 0.001). Complications not requiring reoperation were reported for 19 (0.3%) open, 22 (1.0%) hand-assisted LN, and 24 (0.8%) non-hand-assisted LN cases (p = 0.02). Readmission rate was higher for LN (1.6%) vs. open (0.6%) donors (p < 0.001), almost entirely as a result of an increase in gastrointestinal complications in LN donors. Morbidity and mortality for living donor nephrectomy at transplant centers in the United States remain low. We provide current data from which comprehensive informed consent can be obtained from donors.

Humans↗
PubMed2003

Evolution of a nondirected kidney donor program: lessons learned.

From October 1, 1997 through November 30, 2003, the University of Minnesota received 362 inquiries from potential NDDs. Of these, 53 (15%) then underwent partial or full donor evaluation at our transplant center. Of these 53 potential NDDs, 24 have been accepted (23 donated, and one donation is pending), 23 were denied (15 for medical reasons, 8 for psychosocial reasons), and 6 chose not to pursue donation. Most of our potential NDDs were motivated by altruistic reasons. Their decision-making process was not impulsive or instantaneous, but rather rational and deliberate. They were self-educated about donation before contacting our transplant center. After donation, all 23 of our NDDs said they were glad they donated and were grateful for the opportunity to help another. Many desired to become involved in the transplant community by promoting donation. All NDDs who heard from their recipient appreciated the contact and the chance to learn how the recipient was doing posttransplant. An NDD program clearly mandates a dedicated donor team and additional time and resources, given the high number of inherent practical, logistical, and ethical issues. Our protocol has been a work in progress and continues to evolve with our ever-growing experience. Transplant centers interested in using NDDs must develop NDD protocols to address specific issues and must examine their available staffing and resources.

Academic Medical Centers↗
PubMed2003

Graft and quality of life outcomes in older recipients of a kidney transplant.

BACKGROUND: It is well recognized that kidney transplants significantly improve quality of life for patients with end-stage renal disease (ESRD). This benefit is not as clearly documented for older recipients as it is for younger recipients. We looked at outcomes, both medical and psychosocial, in a group of older (> or =65 years) kidney transplant recipients and compared the results to a group of younger recipients (18 to 64 years). METHODS: From 1990 through 2002, we performed 2,746 kidney transplants at our center: 2,596 (94.5%) in recipients 18 to 64 years old and 150 (5.5%) in recipients 65 years or older. In our retrospective analysis, we determined outcomes such as patient and graft survival rates. To determine whether or not older recipients had an improved health-related quality of life, we used the national SF-36 (short form) questionnaire. We compared those results with a group of younger recipients and with national age-appropriate norms. RESULTS: The mean recipient age was 69.1 years in the older group vs. 42.8 years in the younger group (p < 0.001). Living donors were used in 43.3% of the transplants in the older group vs. 47.5% in the younger group (p < 0.01). At 5 years posttransplant, patient and graft survival rates were 73% and 68% in the older group vs. 86% and 79% in the younger group (p < 0.001). We analyzed the SF-36 responses for all recipients with completed forms: 42 completed forms from the older group vs. 149 from the younger group. The overall benefit to quality of life was similar for both groups. General physical health was rated slightly higher than national norms in both groups. Benefits to mental health were more pronounced in the older group. CONCLUSION: Kidney transplants can be performed in older recipients with acceptable outcomes. Such recipients enjoy significant benefits to their quality of life after a transplant, similar to benefits seen in younger recipients. Older age, by itself, should not be a contraindication to a transplant.

Adult↗
PubMed2002

The nondirected live-kidney donor: ethical considerations and practice guidelines: A National Conference Report.

BACKGROUND: The success of kidney transplantation from a genetically unrelated living spouse or friend has influenced transplant physicians to consider the requests of individuals wishing to volunteer to be a kidney donor who have no intended recipient specified. Representatives of the transplant community gathered in Boston, MA, on May 31, 2001, to deliberate on the experience of live kidney donation from such volunteers, currently termed nondirected donors (NDD). OBJECTIVE OF CONFERENCE PARTICIPANTS: The objective of the conference was to recommend ethical and practice guidelines for health care professionals considering the transplantation of a kidney from a live NDD. CONFERENCE PARTICIPANTS: This conference was convened under the sponsorship of The National Kidney Foundation, with representation from The American Society of Transplantation and The American Society of Transplant Surgeons, The American Society of Nephrology, The United Resource Networks, The United Network for Organ Sharing, The Association of Organ Procurement Organizations, The National Institutes of Health, and The Division of Transplantation of the Health Resources and Services Administration (see Appendix). CONFERENCE REPORT: The suggested content of screening interviews, which provide information regarding the donation process, elicits pertinent medical and psychosocial history, and assesses NDD motivation are presented in this report. Approaches to identifying the center that would evaluate the suitability of the NDD, to performing the kidney recovery, and to selecting the NDD recipient are also proposed. Other ethical issues such as the use of prisoners as an NDD, compensation for the NDD, media involvement, and communication between the NDD and recipient are discussed. CONCLUSION: The willingness of health care professionals to consider NDD volunteers is driven by the compelling need to provide organs for an ever-expanding list of patients awaiting a kidney transplant. However, the psychological impact and emotional reward of donation has yet to be determined for NDD who may not have any relationship to the recipient or knowledge of the recipient's outcome. Transplant centers that accept NDD should document an informed consent process that details donor risks, assures donor safety, and determines that the goals and expectations of the NDD and the recipient can be realized.

Communication↗
PubMed2002

Life satisfaction and adverse effects in renal transplant recipients: a longitudinal analysis.

INTRODUCTION: Previous cross-sectional analyses have identified significant associations between quality of life (QOL), comorbidities and adverse effects in renal transplant recipients. This report examines the longitudinal relationship between adverse effects and QOL, with particular attention to the relative impact of adverse effects associated with immunosuppression. METHODS: The Transplant Learning Center (TLC) is a program designed to improve QOL and preserve graft function in transplant recipients. Self-selected enrollees filled out questionnaires at roughly 3-month intervals. Each questionnaire included QOL scales developed for the program. Repeated measures multiple regression analysis was used to examine the relationship between the QOL scales, comorbidities, adverse effects, adjusting for other factors. RESULTS: A total of 4247 TLC enrollees were included in the analysis, with a mean time since transplant of 5.1 yr. Comorbidities and adverse effects were common, with high blood pressure reported by 87% of respondents and unusual hair growth reported by 69.6%. In bivariate analysis, emotional/psychological problems and headaches had the largest impact on QOL. In multivariate analysis, emotional/psychological problems decreased sexual interest or ability, and headache had the largest adverse QOL effect. CONCLUSIONS: We have identified QOL issues that have been previously underemphasized in transplant recipients. These findings open new areas of research to further explore and define these issues. They provide new opportunities for interventions to address factors adversely impacting QOL and to develop strategies to improve QOL in these patients. Clinicians should actively solicit information about adverse effects of medications, particularly information about sexual and relationship issues, when evaluating renal recipients. These issues should be taken into account when making therapeutic decisions.

Comorbidity↗
PubMed2002

Morbidity from congenital hepatic fibrosis after renal transplantation for autosomal recessive polycystic kidney disease.

Presentation of autosomal recessive polycystic kidney disease (ARPKD) ranges from severe renal impairment and a high mortality rate in infancy to older children and adolescents with minimal renal disease and complications of congenital hepatic fibrosis (CHF), cholangitis and portal hypertension. Renal transplantation improves prognosis but it is unclear whether CHF in transplanted children follows the same clinical course as in older children with less severe renal disease. The aim of this study was to evaluate morbidity from CHF in ARPKD post renal transplantation. Data were analyzed for six males and eight females, transplanted for ARPKD (mean age 8.3 years, range 1-22.3 years) at the University of Minnesota between 1972 and 1998. Follow-up was for a mean of 14.5 years (range 3.1-33.6 years). One and 5 years patient survival rates were 93% and 86%, respectively. Overall five patients (36%) died; 4/5 deaths were related to CHF. Causes of death were hepatic failure immediately post transplant (n = 1), septicemia related to bile duct dilatation (n = 3) and multiorgan failure (n = 1). One and 5years graft survival rates were 87% and 70%, respectively. One patient had a combined liver-kidney transplant and two were re-transplanted. Initial signs of CHF were splenomegaly (n = 5), hepatosplenomegaly (n = 4) and gastrointestinal bleed (n = 2). Progression of CHF through childhood included hypersplenism (n = 7), esophageal varices with gastrointestinal bleeding (n = 5) and bile duct dilatation (n = 5). Portal hypertension was treated with portosystemic shunt (n = 3), sclerotherapy (n = 2), banding of varices (n = 1) and transjugular intrahepatic portosystemic shunt (n = 1). Of the nine survivors (mean age 12.8 years) 78% have functioning grafts (one liver-kidney transplant), 63% have portal hypertension and 22% have asymptomatic biliary dilatation. Complications of CHF developed in 79% of children who received a renal transplant for ARPKD. Mortality related to CHF occurred in 29% and accounted for 80% (4/5) of the deaths.

Adolescent↗
PubMed2002

Long-term (20-37 years) follow-up of living kidney donors.

Numerous studies with <20 years of follow-up have shown no significant long-term consequences of living kidney donation. However, hypertension and proteinuria have both been described; it is unknown whether either complication presages future kidney dysfunction. Between June 1, 1963, and December 31, 1979, we did 773 living donor kidney transplants for 715 recipients. We attempted to contact all donors to determine long-term outcome regarding their remaining kidney. We obtained information on 464 (60%) of the donors. Of these, 84 had died and 380 were alive; of the 380, 256 returned a questionnaire and 125 sent in current laboratory results and/or records of a recent history and physical examination. Of the 84 donors who had died, three were known to have had kidney failure. Of the 380 still alive, three had abnormal kidney function and two had undergone transplantation. The remaining donors had normal kidney function. The rate of proteinuria and hypertension was similar to the age-matched general population. We conclude that most kidney donors have normal renal function 20-37 years post donation. However, some do develop renal dysfunction; some, renal failure. Our data underscore the need to develop prospective trials for long-term follow-up of kidney donors.

Adult↗
PubMed2002

Predictors of renal function following lung or heart-lung transplantation.

BACKGROUND: Renal failure is a common complication following non-renal solid organ transplantation. The purpose of our study was to define the rate of decline in renal function and to identify independent risk factors associated with renal failure following lung or heart-lung transplantation. METHODS: Between May 1986 and December 1998, 219 patients underwent lung or heart-lung transplantation at the University of Minnesota and survived at least six months (33 heart-lung, 66 bilateral single lung, and 120 unilateral single lung transplants). The mean age at the time of transplant was 45.9 +/- 11.6 years (mean +/- SD; range, 15 to 65 years), and the mean pre-transplant serum creatinine level was 0.88 +/- 0.19 mg/dL. All patients were treated with a calcineurin inhibitor (164 cyclosporine, 55 tacrolimus). RESULTS: During the follow-up period (median 44 months, range 6.8 to 163 months), 16 patients (7.3%) developed end-stage renal disease. The cumulative incidence of doubling of serum creatinine was 34% at one year, 43% at two years and 53% by five years. Factors associated with the primary end point of the time to doubling of the baseline serum creatinine by proportional hazards regression were cumulative periods with diastolic blood pressure greater than 90 mm Hg [relative risk (RR) 1.30, P = 0.02] and the serum creatinine value at one month post-transplantation (RR 1.28, P = 0.03). Use of tacrolimus during the first six months after transplantation was associated with a significant decrease in the risk for time to doubling of serum creatinine (RR 0.38, P = 0.009) and a lower rate of acute rejection. CONCLUSIONS: These results suggest that potential renoprotective strategies following lung or heart-lung transplantation include avoidance of peri-transplant renal injury, diligent blood pressure control, and preferential use of tacrolimus over cyclosporine.

Acute Disease↗