Live Kidney Donor Study - Cross-Sectional and Historical Cohort Study

Kidney transplantation from living donors has been shown to carry many benefits over deceased donor transplantation. Because of benefits such as shorter waiting times and improved outcome for transplant recipients, living kidney donation accounts for an increasing number of kidney transplants nationwide. Most published studies about living kidney donation demonstrate that the procedure is safe, but they also emphasize concerns that long-term data on live donor outcomes are insufficient. The purpose of this study is to assess the long term outcomes and risks that may arise from living kidney donation.

Living donor transplants provide several advantages over deceased donor kidneys, including a shorter waiting time. Living donor grafts also appear to have a lower rate of delayed graft function and improved long-term recipient and graft survival. Most published studies of living kidney donation have supported that the donation process is relatively safe for the donor. However, these reports also emphasize concerns that comprehensive long-term data on U.S. live donor outcomes are insufficient. One concern is that current data may underestimate the true long-term morbidity and mortality of living kidney donation. Additionally, older studies might not apply to the current donor population that includes older and more obese individuals.

This is an observational study to look at the long term outcomes in living kidney donors. This study also seeks to find out if living kidney donors are at higher risk for certain conditions when compared to people of similar backgrounds who have not donated a kidney. Medical history, completed questionnaires, and blood and urine tests will be collected from donors and non donors. The compiled data from donors and non donors will be compared. Risks for diseases related to the kidney, heart, and blood vessels will be examined between the two groups. Quality of life and health insurance status will also be compared.

The study will be conducted in 2 phases. All donors who donated a kidney between 5 and 50 years ago at one of the three study transplant centers will be asked to take part in Phase 1. Phase 1 aims to collect limited medical information using a short questionnaire. Phase 2 will include Phase 1 donors who agree to further assessments and matched community control participants. Participants in Phase 2 will be asked to complete more in-depth questionnaires on health status and quality of life. Phase 2 also involves height, weight, and blood pressure measurements. Blood and urine will be collected for this study if the participant does not have the necessary tests within 3 years of study participation.

Seven thousand-eight hundred-sixty four (7864) previous kidney donors and about two thousand-five hundred (2500) control subjects will be asked to take part in this study. Participants will be recruited for this study over a 2.5.

Eligibility Criteria:
Inclusion Criteria:

* Underwent a unilateral donor nephrectomy between 5 and 50 years ago; but no later than June 30, 2005
* Alive at the time of study recruitment

Exclusion Criteria:

* Inability to contact donor

Community Control Inclusion Criteria:

* Matched to donor as healthy subject with a medical encounter date within 5 years of the date of donation and alive at the time of study recruitment
* Same gender as donor
* Same race as donor
* Matched by age, not to differ by more than 2 years
* Matched by BMI, not to differ by more than 5 kg/m\^2 (JHS only)

Community Control Exclusion Criteria:

* Inability to contact control participant
* Inability or unwillingness to provide informed consent
* Hypertension or identified Charlson comorbidity index variable diagnosed prior to or on the encounter date matched to the donor date of donation (REP only)