Proteinuria, graft outcomes, and cardiovascular risk among kidney transplant recipients in a South African Public Hospital

Abstract

Proteinuria is a marker of poor long-term graft survival and an independent risk factor for total and cardiovascular mortality in the transplant population. We investigated the prevalence of proteinuria and its relationship with graft function and cardiovascular risk factors in kidney transplant recipients (KTRs). Adult KTRs at the Charlotte Maxeke Johannesburg Academic Hospital were recruited. Patients′ records were reviewed for information on their posttransplant follow-up. Echocardiography and carotid Doppler were performed for the assessment of cardiac status and carotid intima-media thickness (CIMT), respectively. Proteinuria was analyzed both as a categorical and continuous variable. Graft dysfunction was defined as estimated glomerular filtration rate of <60 mL/min/1.73 m 2 based on the modification of diet in renal disease formula. Framingham′s risk score was used to categorize patients′ cardiovascular risk. Inferential and modeling statistics were applied as appropriate using Statistical Package for Social Sciences, and P ≤0.05 was considered statistically significant. One hundred KTRs including 63% males were recruited. Proteinuria was present in 51%, the mean ± standard deviation 24 h urinary protein excretion per day was 1.67 ± 2.0 g/day with a range of 0.4-9.4 g/day. Graft dysfunction was found in 52% of patients and 36% had high cardiovascular disease (CVD) risk. Proteinuric KTRs had high CVD risk, P = 0.002. Proteinuria was associated with graft dysfunction, increased left ventricular mass index, increased CIMT, and anemia. Proteinuria is prevalent; it is a marker of graft dysfunction and is associated with markers of atherosclerosis.