Fracture risk in living kidney donors: a matched cohort study
Garg AX, Pouget J, Young A, Huang A, Boudville N, Hodsman A, Adachi JD, Leslie WD, Cadarette SM, Lok CE, Monroy-Cuadros M, Prasad GV, Thomas SM, Naylor K, Treleavan D; Donor Nephrectomy Outcomes Research (DONOR) Network. Am J Kidney Dis. 2012; 59(6):770-6. Epub 2012 Apr 1.
Background — Chronic kidney disease increases the risk of bone fragility fractures (osteoporotic fractures). Living kidney donors lose 50% of their renal mass and show changes in calcium homeostasis. We studied whether living kidney donation increases the risk of fragility fracture.
Design — Retrospective matched-cohort study.
Setting and Participants — We reviewed the medical charts of all 2,015 adults in Ontario, Canada, who donated a kidney between 1992 and 2009 (surgeries performed across 5 transplant programs). We linked this information to health care databases and randomly selected 20,150 matched nondonors from the healthiest portion of the general population. Median age was 43 (95% CI, 24-50) years at study enrollment. Donors and nondonors were then followed up for a median of 6.6 years and a maximum of 17.7 years.
Predictor — Living donor nephrectomy.
Outcomes — The primary outcome was lower- and upper-extremity fragility fractures. Individuals who reached 66 years or older in follow-up had bisphosphonate prescriptions recorded.
Results — The rate of fragility fracture was no higher in donors compared with nondonors (16.4 vs 18.7 events/10,000 person-years; rate ratio, 0.88; 95% CI, 0.58-1.32). Results were similar in multiple additional analyses. There was little difference in the proportion of older adults in follow-up who received a bisphosphonate prescription (17.1% vs 15.2%; P = 0.4).
Limitations — These are interim results. Ongoing surveillance of this and other donor cohorts is warranted to be sure an association does not manifest with longer follow-up.
Conclusions — To date, there is no evidence of increased fragility fracture risk in living kidney donors. Our results meet an information need and are reassuring for the safety of the practice.
Kidney and urinary tract disorders
Musculoskeletal and joint diseases