**3. Evaluation of risk factors related to specific patients' characteristics**

listed for a standard and ECD kidney. Although living donor kidneys offer older transplant candidates the best chance of meaningful improved survival and quality of life, older patients are often reluctant to accept living donor kidneys from their children or grandchildren. These issues must be discussed with patients and their families with particular care and compassion to optimize the chance of a satisfactory outcome. Nonetheless, it should be noted that extreme recipient-donor age pair (e.g recipient > 80 years and donor aged 20-30 years) may represent

Medical Evaluation of the Adult Kidney Transplant Candidate

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Obesity is considered a contraindication to transplantation by some centers as it is associated with increased risks of posttransplant complications including delayed graft function, surgical wound infection, and death, particularly from cardiovascular disease. Although there has been no consensus on an acceptable upper limit body mass index (BMI), weight reduction to a BMI

benefit from surgery referral for gastric bypass surgery or gastric banding procedure, or more recently, laparoscopic sleeve gastrectomy. However, it should be noted that there has been limited data on the safety and efficacy of bariatric surgery (BS) in renal transplant candidates. The USRDS registry data (1991-2004) demonstrated a median excess body weight loss of 31%-61% after bariatric surgery, with thirty-day mortality rate of 3.5% (72 were performed on pre-listed, 29 on waitlisted, and 87 on posttransplant patients). One graft was lost within 30 days after BS. (Modanlou et al. 2009). The authors concluded that although peri-operative mortality was not negligible, the rate may be lower with experienced surgeons and comparable

Data on patient and graft survival in obese *versus* non-obese transplant recipients are variable and contradictory. Determination of transplant candidacy in obese patients should, therefore, be assessed on an individual basis rather than reliance on an absolute BMI index. Obese candidates with comorbid conditions such as known coronary artery disease and advanced

Whereas the number of patients on the transplant waiting list has steadily increased, the number of deceased donor kidneys has remained far below the growing need, leading to longer waiting time and increased wait-list deaths. Hence, managing the wait-list has been one of the greatest problems facing transplant centers. Periodic reassessment of transplant candidates' medical and psychosocial issues entails ongoing communication between the dialysis units, patients, and transplant coordinators and transplant programs. In the event of a significant intercurrent illness that may necessitate delisting or placing candidates on hold, pertinent medical records should be obtained and reviewed by a transplant physician. If necessary, patients must be seen to reassess their candidacy. Most transplant programs attempt to see transplant candidates on an annual basis to update their overall heatlh and demographic issues although older candidates may require more frequent visits at the discretion of the transplant physician. During the follow-up visit, routine health maintenance status and cancer screening

or less prior to transplantation is recommended. Morbidly obese candidates may

a great challenge for the clinicians as well as patients and their families.

to trials involving patients without kidney disease.

**3.3. Managing the wait-list candidates**

age are at particularly high risk and may fare better receiving dialysis.

**3.2. Obesity**

of 30-35kg/m2

#### **3.1. Advanced age**

There is no arbitrary age limit for transplantation. The United Network for Organ Sharing/ Organ Procurement Transplantation (UNOS OPTN) database revealed that the number of kidney transplants performed in patients ≥ 65 has more than tripled over the last decade (ww.unos.org). Similar to the younger population, transplantation in the older age group of 60 to 74 years has been shown to improve survival compared to their wait-listed counterparts. Graft loss from rejection is lower in older compared to younger recipients presumably due to the decreased immune responsiveness in the aged population. It must be noted, however, that older transplant recipients are at increased risks for infectious complications, malignancy related to immunosuppression, and deaths in the early posttransplant period, most often as a consequence of cardiovascular disease.

Although advanced age *per se* has not been regarded as contraindication to transplantation, kidney transplantation among recipients over 80 years of age is uncommonly performed. Analysis of the UNOS/OPTN database revealed that of the transplants performed between 2000 and 2007 in recipients ≥ 60 years of age, only 0.6% were older than 80 years of age. For statistical analysis purposes, patients were divided into three age groups, 60-69, 70-79, and > 80 years with recipients aged 60-69 years used as reference. Median ages for recipients aged 60-69, 70-79, and > 80 years were 64, 72, and 81 years, respectively. Most of the differences were seen between recipients aged 60-69 and > 80 years. The rates of living donor transplants were lower in recipients > 80 years compared to 60-69 years (18% vs. 32%, respectively). The acute rejection rate at 1-year among recipients > 80 years was comparable to that of recipients 60-69 years of age. Three-year patient survival was significantly lower in recipients older than 80 years compared to recipients aged 60-69 years (64% vs. 84%, respectively) with an unadjusted relative risk of death of 2.35 (95% CI 1.83-3.03). However, graft survival was excellent and did not differ significantly between the two groups (88% vs. 90%) (Poommipanit et al., 2010). Hence, the assessment of transplant candidacy for patients over 80 years of age remains a challenge for transplant physicians. Screening for covert cardiovascular disease and occult malignancy, and careful assessment of infectious risk in older prospective transplant candi‐ dates are crucial and mandatory.

Currently, the waiting time for a deceased donor transplant in the United States is such that many wait-listed older transplant candidates die while awaiting transplantation from a standard deceased donor kidney. Furthermore, the duration of pretransplant dialysis has been shown to confer a significant and progressive increase in the risk of death-censored graft loss and the risk for patient death after transplantation. Compared with preemptive renal trans‐ plantation, waiting time of 0-6 months, 6-12 months, 12-24 months, and over 24 months conferred a 17%, 37%, 55%, and 68% increase risk for death-censored graft loss after trans‐ plantation, respectively (Meier-Kriesche et al., 2000). Similarly, mortality risk after transplan‐ tation was significantly increased with increasing waiting time on dialysis. It is our center practice to offer the expanded criteria donor (ECD) program to all candidates 50 years of age or older. Patients should be informed that candidates for ECD kidneys are simultaneously listed for a standard and ECD kidney. Although living donor kidneys offer older transplant candidates the best chance of meaningful improved survival and quality of life, older patients are often reluctant to accept living donor kidneys from their children or grandchildren. These issues must be discussed with patients and their families with particular care and compassion to optimize the chance of a satisfactory outcome. Nonetheless, it should be noted that extreme recipient-donor age pair (e.g recipient > 80 years and donor aged 20-30 years) may represent a great challenge for the clinicians as well as patients and their families.
