A NEW study has examined the effects of kidney donation on mineral and bone metabolism (MBD) in living kidney donors (LKD), finding that while the body adapts to the immediate loss of kidney function, some metabolic changes persist long term. Conducted at transplant centres in São Paulo, Brazil, and Miami, USA, the study followed 74 donors over a year, with a subset of Brazilian donors reassessed 10 years post-donation.
Immediately after donation, the kidney donors experienced a sharp decline in glomerular filtration rate (GFR), which stabilised to about 63% of baseline levels. This reduction in kidney function was accompanied by an increase in parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF23), key markers in bone and mineral metabolism. Serum phosphate dropped initially but returned to normal within six months, while FGF23 levels remained elevated throughout the first year.
Over the long term, some metabolic changes persisted. Ten years post-donation, a subset of Brazilian donors still showed reduced GFR levels, alongside persistent elevations in PTH and reductions in calcitriol and Klotho, proteins crucial for mineral balance and bone health. The observed increase in serum calcium and changes in MBD parameters suggest lasting adaptations in the body’s response to decreased kidney function.
These findings highlight that while kidney donors generally experience manageable short-term metabolic effects, there may be lingering implications for bone and skeletal health years after donation. The researchers call for further studies to explore the long-term health impacts of these metabolic changes, particularly the sustained elevation of PTH and reduced levels of calcitriol and Klotho. This research underlines the importance of long-term monitoring for kidney donors to ensure early detection and management of potential metabolic and skeletal complications.
Reference
Duque EJ et al. Short and long-term effects of kidney donation on mineral and bone metabolism. BMC Nephrol. 2024;25:381.
