Reduced Calorie Diet Intervention in Kidney Transplant Recipients

Kidney transplantation is the preferred renal replacement therapy for end stage renal
disease (ESRD) because it affords survival and quality of life advantages over maintenance
dialysis.1 The number of transplants performed increases each year, with currently over
150,000 individuals living in the United States with a kidney transplant. This is in the
setting of 68,000 patients on the wait list with a median wait time of 4 years for an
available organ.2 Despite the survival benefit over dialysis, transplanted patients still
have a greatly increased risk of cardiovascular disease (CVD) over the general population,
and CVD is the leading cause of death among recipients with a functioning graft.3 Given the
long wait times for kidneys due to organ shortage, extensive resources used, and support
needed for each transplant procedure, it is imperative that we improve long term patient and
graft survival. Accordingly, modification of CVD risk profile is of paramount importance in
kidney transplant patients.

The etiology of increased risk of CVD in kidney transplant patients is multi-factorial and
includes the high burden of CVD and its risk factors present prior to transplant, as well as
increasing prevalence of these risk factors in the post transplant period due to transplant
associated weight gain, immunosuppression side effects, metabolic consequences of a
functioning kidney, and allograft dysfunction. Efforts to reduce CVD risk factors have yet
to be adequately implemented and rigorously studied in the kidney transplant population.

Obesity at the time of transplant is common and associated with several CVD risk factors
post transplant, including hypertension, hyperlipidemia, diabetes mellitus, metabolic
syndrome, and inflammation. Obesity is also associated with potentially poorer graft
outcomes, including death censored graft loss and chronic allograft failure.4 In addition,
the majority of patients gain weight post transplantation, primarily in the form of fat
mass. Post transplant weight gain is also associated with increased prevalence of known CVD
risk factors, CVD death, and graft loss.5 The increased burden of CVD in kidney transplant
patients makes obesity prevention and treatment strategies appealing interventions to
improve long-term outcomes, both in terms of graft and overall survival. In this study we
will measure the effect of a low calorie diet intervention in new kidney transplant
recipients on the outcomes weight gain, oxidative stress, and insulin resistance.

Inclusion Criteria:

- Age 18 years to 65 years;

- BMI 25 to 40 kg/m2;

- First time kidney transplant;

- Single organ transplant;

- Ability to understand and voluntarily provide informed consent.

Exclusion Criteria:

- Type 1 DM;

- Type 2 DM on diabetic medications/insulin;

- Biopsy proven acute rejection in the first 3 months post transplant;

- Active coronary disease;

- Immunosuppressive therapy at time of transplant (use prior to what is given for
transplant procedure);

- Atrial fibrillation (only for those undergoing the optional Pulse Wave Velocity);

- Hypersensitivity to organic nitrates, isosorbide, or nitroglycerin (only for those
undergoing the optional brachial artery Doppler).