Risk factors for MDRD-GFR of less than 60 mL/min per 1.73 m² in former kidney donors

Background:  Although several previous studies have reported that kidney donors are not at increased risk for adverse effects, some donors have been found to progress to chronic kidney disease (CKD). We retrospectively evaluated the risk factors for estimated glomerular filtration rate (GFR) from abbreviated Modification of Diet in Renal Disease (MDRD) equation (MDRD-GFR) of less than 60 mL/min per 1.73 m² in kidney donors.

Methods:  Of the 756 individuals who underwent open donor nephrectomy between 27 June 1990 and 30 April 2001, 104 had follow-up records for 50 months or more. MDRD-GFR of 60 mL/min per 1.73 m² at final follow up divided these individuals into a normal group (n = 78) and a CKD-GFR group (n = 26). We compared several clinical parameters between the two groups at baseline and follow up to evaluate the risk factors for MDRD-GFR of less than 60 mL/min per 1.73 m² in kidney donors.

Results:  The CKD-GFR group was significantly older than the normal group at baseline (47 ± 12 vs 41 ± 11 years old, P = 0.02). Hypertension was more prevalent in the CKD-GFR group at baseline (15% vs 2%, P = 0.005). Binary logistic regression analysis showed that age (Odds ratio (OR) 1.06, 95% confidence interval (CI) 1.01–1.10) and hypertension (OR 7.91, 95% CI 1.13–55.2) at baseline were independent risk factors for MDRD-GFR of less than 60 mL/min per 1.73 m². At final follow up, the prevalence rates of hypertension (31% vs 8%, P = 0.006) and proteinuria (15% vs 0%, P = 0.003) were significantly higher in the CKD-GFR group.

Conclusion:  Older kidney donors and those with hypertension were significantly more likely to have a MDRD-GFR of less than 60 mL/min per 1.73 m².