African Americans (AA) with two apolipoprotein L1 (APOL1) risk alleles have more kidney disease than compared to those with one or zero risk alleles. A critically important question is whether AA live kidney donors with two APOL1 risk alleles experience more hypertension and reduced renal function following donation. In a retrospective cohort study at two transplant centers, we enrolled AA who donated a kidney between 1990 and 2010. To date, 101 live kidney donors have been genotyped for APOL1 risk variants and assessed for development of hypertension, reduced kidney function, ESRD and microalbuminuria. We defined hypertension as BP >140/90 or use of medication, reduced renal function as CKD-EPI eGFR <60 mL/min, ESRD as need for dialysis or transplant, and microalbuminuria as urine albumin/creatinine excretion (UAE) >30mg/g. Baseline donor characteristics at the time of nephrectomy were: age 39±10 years, 36% male, BMI 29±8 kg/m² and eGFR 107±21 mL/min; 6% were hypertensive and 78% donated to first degree relatives. The donors were grouped as high-risk genotype if they had two APOL1 risk alleles (n=21, 20%) and low-risk if they had zero/one risk allele (n=80, 80%). There was no difference in pre-donation characteristics between two groups. At median follow-up of 12 years after donation, 48% were hypertensive, 43% had eGFR <60 mL/min, and 17% had microalbuminuria. One donor developed ESRD after 18 years after donation due to collapsing FSGS. After excluding donors with hypertension at donation, there was no difference in prevalence of hypertension between two groups (57% vs. 47%; p=0.40). The genotype groups also showed no difference in prevalence of reduced renal function (50% vs. 41%; p=0.47) and ESRD (5% vs. 0%; p=0.2); but the high-risk group had more microalbuminuria (33% vs. 12%; p=0.02). In multivariate analyses adjusted for sex, age and BMI at transplant and follow-up duration, the presence of two APOL1 risk alleles was not associated with new onset hypertension, reduced renal function, or microalbuminuria. These preliminary data suggest that AA live kidney donors with the high-risk APOL1 genotype may not have increased risk for hypertension and kidney disease. Given the sample size, further studies are required to confirm that these individuals can safely donate a kidney.

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