Uric Acid May Predict Graft Survival
Each 1 mg/dL rise after renal transplantation associated with a 30% increased risk of graft loss.
The findings, reported here at the 2007 American Transplant Congress, suggest that nephrologists should measure uric acid levels following renal transplantation, said
“This is not routinely measured in most transplant patients so it may be important to check it from time to time. If the levels are high, then recommend a special diet to decrease them, and minimize the use of diuretics, which are associated with increase in uric acid levels.”
It is well known that elevated uric acid levels increase the risk for the development and progression of hy-pertension and kidney disease, but the role of uric acid as a risk factor for renal transplant outcomes is not well studied, according to Dr. Haririan. He and his colleagues retrospectively studied 213 recipients of kidneys from live donors. The transplants were performed between January 2000 and December 2001 at one institution.
All recipients had serum uric acid levels examined during the first six months post-transplant. The patients had a mean age of 47.9 years, 55.9% were male, 27.7% were African American, and 44.6% had diabetes mellitus. They had a mean BMI of 26.8 kg/m2. Seven percent were re-transplant patients. The median number of uric acid values available for each patient was 10, and the mean uric acid level was 5.7 mg/dL for men and 5.2 mg/dL for women.
The patients were followed for a mean of 3.8 years after transplantation. At one year, the mean serum creatinine level was 1.6 mg/dL, and 18 graft losses had occurred. After adjusting for several covariates, the six-month mean uric acid levels were a significant predictor of one-year creatinine levels and graft loss.
Each 1 mg/dL increase in uric acid level was associated with a 30% increased risk of graft loss. Hyperuricemia—defined as uric acid levels greater than 6.0 mg/dL in women and greater than 7.0 mg/dL for men—was associated with a 110% increased risk of graft loss.
“If prospective studies confirm this association, then decreasing hyperuricemia with currently available drugs will help improve graft survival and graft function,” Dr. Haririan said.