Introduction: Stable long term kidney function and safety of the donor nephrectomy are essential prerequisites for the living kidney donation. In our retrospective multicenter analysis we evaluated the impact of selected risk factors (age, BMI, arterial hypertension) on the severity of change in glomerular filtration rate (GFR) after kidney donation.

Materials and Methods: In the period of years 2015 to 2019  there were 35 open and 46 hand assisted retroperitoneoscopic (HARS) donor nephrectomies performed in 4 transplant centers. 78 donors were eligible for analysis. Mean follow up of the donors was 3 ± 1,4 years. GFR was calculated according to CKD-EPI formula before donation (eGFR_baseline), at the time of maximal decrease (eGFR_min) and at the end of follow up (eGFR_end). ∆GFR refers to the change of eGFR in a donor and is expressed as a difference between eGFR_baseline and eGFR_min (∆GFR_max) or eGFR_end (∆GFR_end) respectively. We used unpaired t test, Fisher test and linear regression for statistical analysis.

Results and Discussion: We found strong correlation between ∆GFR_end and eGFR_baseline, (r=0.5111, p< 0.0001).  Age, BMI and eGFR_min did not correlate with ∆GFR_end. Hypertensive donors did not have significantly higher  ∆GFR_end than normotensive donors (-26.9 vs. -24.6ml/min, p=0.49).  32 donors (41%) had eGFR_baseline between 60-90ml/min/1,73m2.  In comparison with the subgroup of donors whose eGFR_baseline was more than 90 ml/min/1,73m2, these donors were older (52.2±8.8 vs 46.1±8.6 years, p=0.0034) and  their ∆GFR_max and ∆GFR_end were lower (-28.2 ± 12.7 ml/min vs -43 ± 9.6ml/min, p<0.0001 for ∆GFR_max and -16.3 ± 13 ml/min  vs -32.1 ± 10.4 ml/min, p<0.0001 for  ∆GFR_end). No donor reached eGFR less than 30 ml/min/1,73m2 at the end of follow up.

Conclusion: Our results  demonstrate favourable mid term renal outcomes even in living kidney donors with slightly reduced predonation eGFR.