Individuals who receive a solid organ transplant in the United States are followed up annually for assessment of their health status. These data are recorded in the Scientific Registry of Transplant Recipients (SRTR). All analyses presented are limited to adults, 20 years of age and older, at the time of their first organ transplant. These data are nationally-representative of the first-time, solid-organ transplant population with fewer than 5% lacking information on kidney function.

Individuals who receive a solid organ transplant in the United States are followed up annually on the anniversary of the transplant date for an assessment of their health status. These data are recorded in the Scientific Registry of Transplant Recipients (SRTR). All analyses presented are limited to adults, 20 years of age and older, at the time of their first organ transplant. Diabetes status (type 1 or 2) and hypertension status are as listed at the time of transplant. For all transplant recipients, use of calcineurin inhibitors (CNI) to prevent transplant rejection is presented as many of these medications have been shown to be nephrotoxic (see Ojo, 2007, for a review). The recording of data in the SRTR pertaining to CKD/kidney function varies by organ type and is discussed below.

Information on kidney transplant recipients includes serum creatinine measurements for each follow-up visit as well as whether the patient has been treated for end-stage renal disease (ESRD) through dialysis or a kidney retransplant since the last follow-up. CKD stages 3-5 is defined by an MDRD study equation estimated eGFR <60 ml/min/1.73 m². Additional data collected for kidney transplant recipients includes donor type (deceased vs. living donor), and whether the donor was considered an expanded criteria donor (e.g. a donor that may have been advanced in age, diabetic, had prior infection with hepatitis B or C, etc.).