NEW YORK (Reuters Health) – Carefully selected kidney donors can expect to live just as long as people in the general population and experience no significant drop in kidney function, according to a report in The New England Journal of Medicine for January 29.

Prior research has supported the belief that kidney donation is safe, with no impact on survival or kidney function, lead author Dr. Hassan N. Ibrahim, from the University of Minnesota Medical School in Minneapolis, and colleagues explain. Still, most studies examining this topic have had relatively small sample sizes with only limited follow-up.

To examine long-term safety further, Dr. Ibrahim’s team analyzed data from 3698 individuals who donated kidneys from 1963 to 2007. In 255 donors whose surgery was performed in 2003 or later, the researchers assessed glomerular filtration rate (GFR), albuminuria, hypertension, general health status, and quality of life.

No significant difference in survival was noted between donors and age-matched controls, the report indicates. Moreover, end-stage renal disease was actually more common in controls than in donors: 268 vs. 180 cases per million per year.

During a mean follow-up period of 12.2 years, 85.5% of subjects in the subgroup analysis had a GFR of at least 60 mL/min/1.73 m² of body-surface area. Hypertension and albuminuria were seen in 32.1% and 12.7% of subjects, respectively.

Older age and higher body mass index were predictive of hypertension and a reduced GFR on long-term follow-up. By contrast, a longer time since donation did not correlate with a reduced GFR and hypertension, although it was linked to albuminuria.

Quality of life was not adversely impacted by donation and, in fact, donors usually had scores that were better than those in the general population. Comorbid conditions were seen with comparable frequency in the donor and general populations.

Noting that the donors studied were relatively young and mostly white, editorialists Dr. Jane C. Tan and Dr. Glenn M. Chertow, from Stanford University School of Medicine, Palo Alto, comment that further studies are needed to determine if the findings are applicable to older and nonwhite donors. Still, data from the current study “could encourage the expansion of the donor pool, but cautious optimism is warranted.”

N Engl J Med 2009;360:459-469,522-523.