A long-term study on hyperlipidemia in stable renal transplant recipients

OBJECTIVES: Hyperlipidemia is a common and important risk factor after renal transplantation, but there is little long-term data on its incidence, pattern, and evolution in stable renal allograft recipients on low dose maintenance immunosuppression. PATIENTS AND METHODS: A retrospective study was conducted on all patients who received kidney transplants from April 1, 1990 to March 31, 2000 at a single center, on their serial lipid profile during the first 3 yr after kidney transplantation. RESULTS: A total of 221 (122 male, 99 female; mean age 37.8 +/- 10.0 yr at the time of transplantation) Chinese adult renal allograft recipients were included. A 95.3% of patients were on cyclosporine and prednisolone based immunosuppression. Increases in total cholesterol (TC), low density lipoprotein (LDL), and high density lipoprotein (HDL) were noted, while the level of triglyceride (TG) decreased after renal transplant. The incidence of hypercholesterolemia (defined as TC >/= 6.3 mmol/L or LDL >/= 4.2 mmol/L) within the first year was 28.2 and 20.3%, respectively. The incidence rate decreased significantly in the second (5.4%, p = 0.000 and 6.4%, p = 0.003) and third year (9.5%, p = 0.003 and 4.9%, p = 0.021), but the incidence of patients having a high risk-ratio (defined as TC/HDL >/= 5) remained unchanged (6.9, 4.9 and 10.3% within the first, second, and third year, respectively). Treatment with statin was necessitated in 6.8, 13.6 and 21.7% of the patients at 1, 2, and 3 yr after transplantation, respectively. The prevalence rates of elevated TC and LDL were 18.3 and 18.9% at baseline, 40.6 and 33.3% after 1 yr, 32.8 and 27.3% after 2 yr, and 24.8 and 19.0% after 3 yr, despite treatment. The prevalence of patients with a high risk-ratio was 45.0% at baseline, 30.5% after 1 yr (p = 0.002), 22.6% after 2 yr (p = 0.000) and 21.8% after 3 yr (p = 0.000). Hypercholesterolemia at the time of transplantation was an independent predictor for post-transplant hypercholesterolemia (odds ratio 3.76, 95% confidence interval 1.47-9.62, p = 0.006). CONCLUSION: Renal transplantation is associated with a characteristic pattern of dyslipidemia, with increased TC, LDL and HDL, and a decrease in TG. Patients with pre-existing hypercholesterolemia were at higher risk for post-transplant hypercholesterolemia. Although the incidence of hypercholesterolemia peaks within the first year after transplantation, this remains a long-term complication in a significant proportion of patients on low dose immunosuppressive medications.