What is the average reduction in estimated glomerular filtration rate (eGFR) after living kidney donation?

Average eGFR Decrease After Living Kidney Donation

Living kidney donors experience an immediate decrease in eGFR of approximately 30% following nephrectomy, with the remaining kidney showing compensatory hyperfiltration that results in gradual eGFR improvement over the first 2-5 years post-donation. 1, 2

Immediate Post-Donation Changes

At hospital discharge (typically within one week), donors have an eGFR approximately 30-35 mL/min/1.73 m² lower than their pre-donation baseline. 3

• Donors with pre-donation eGFR of 100-104 mL/min/1.73 m² typically have eGFR of 70 mL/min/1.73 m² at discharge 3
• This represents retention of approximately 65-70% of pre-donation kidney function 3

Long-Term eGFR Trajectory

Unlike healthy non-donors who experience steady age-related decline, kidney donors show a unique pattern of eGFR recovery followed by stabilization. 1

Years 0-2 Post-Donation

• eGFR increases by approximately +1.06 mL/min/1.73 m² per year due to compensatory hyperfiltration in the remaining kidney 1
• This adaptive hyperfiltration occurs without glomerular hypertension, making it relatively benign 2

Years 2-5 Post-Donation

• eGFR continues to increase but at a slower rate of +0.64 mL/min/1.73 m² per year 1
• Donors without incident chronic kidney disease (CKD) show gradual increases in eGFR during this period 4

Beyond 5 Years Post-Donation

• eGFR stabilizes with minimal change of -0.06 mL/min/1.73 m² per year 1
• This plateau represents the completion of compensatory adaptation 1

Overall Long-Term Pattern

• Over a median 7-year follow-up (maximum 15 years), donors showed an average eGFR increase of +0.35 mL/min/1.73 m² per year from 6 weeks post-donation onwards 1
• In contrast, matched healthy non-donors experienced steady decline of -0.85 mL/min/1.73 m² per year 1

One-Year Post-Donation Benchmarks

At one year post-donation, the typical donor eGFR is 70-71 mL/min/1.73 m² for those with pre-donation eGFR around 100-104 mL/min/1.73 m². 4, 3

• Approximately 21.7% of donors develop CKD (defined as eGFR <60 mL/min/1.73 m² or proteinuria) by 2 years post-donation 4
• Donors without incident CKD at 2 years show annual eGFR increases of +2.2 mL/min/1.73 m² per year 4
• Donors who develop CKD show minimal change of -0.4 mL/min/1.73 m² per year 4

Factors Affecting Post-Donation eGFR Recovery

Donor Characteristics Associated with Lower Post-Donation eGFR

Age >50 years, female gender, and BMI >25 kg/m² are independently associated with lower eGFR recovery after donation. 5

• Overweight women ≥50 years experience the lowest one-year eGFR of approximately 49.6 ± 8.8 mL/min/1.73 m² 5
• Men <50 years with normal BMI achieve the highest one-year eGFR of approximately 66.6 ± 10.4 mL/min/1.73 m² 5
• Older age (p<0.001), male gender (p<0.001), and overweight status (p=0.01) are associated with greater relative increase in creatinine after donation 5

Predictors of Incident CKD Post-Donation

Higher systolic blood pressure increases CKD risk, while higher pre-donation eGFR and better immediate post-operative eGFR recovery are protective. 4

• Each 10 mmHg increase in systolic blood pressure: OR 1.32 for CKD (95% CI 1.04-1.69) 4
• Each 1 mL/min/1.73 m² increase in pre-donation eGFR: OR 0.91 for CKD (95% CI 0.88-0.94) 4
• Each 0.1 unit increase in ratio of discharge eGFR to pre-donation eGFR: OR 0.60 for CKD (95% CI 0.43-0.85) 4

Clinical Implications for Donor Selection

Pre-donation eGFR should be ≥90 mL/min/1.73 m² according to current guidelines, with donors having eGFR 60-89 mL/min/1.73 m² requiring individualized risk assessment. 6

• Donors with pre-donation eGFR <100 mL/min/1.73 m² have 17.7-fold increased risk of recipient eGFR <60 mL/min/1.73 m² at one year 3
• Donor age >50 years confers 8.9-fold increased risk of recipient eGFR <60 mL/min/1.73 m² at one year 3
• Candidates with eGFR <60 mL/min/1.73 m² should be excluded from donation 6

Important Caveats

The immediate post-operative eGFR ratio (discharge eGFR/pre-donation eGFR) is a critical predictor of long-term outcomes and should be monitored closely. 4

• A low ratio indicates inadequate compensatory response and predicts higher CKD risk 4
• Most donors sacrifice approximately 30% of pre-donation GFR, but this varies significantly by donor characteristics 2, 3
• Despite the immediate decrease, most donors do not experience accelerated age-related GFR decline compared to the general population over long-term follow-up 1, 2