The proportion of children undergoing a kidney transplant who are obese is on the rise, researchers report.

“The concern is that kidney transplantation poses a multiple cardiovascular risk, and obesity might further contribute to the development of premature cardiac disease in these young patients,” Dr. Mark M. Mitsnefes told AMN Health.

Mitsnefes, at Cincinnati Children’s Hospital Medical Center in Ohio, and colleagues studied more than 6600 children (ages 2 to 17 years) who had a kidney transplant between 1987 and 2002 in the US, Mexico or Canada.

The proportion of children who were obese increased from 8 percent before 1995 to 12 percent after that year. Obese children were significantly younger and shorter and had been on dialysis for a longer time than non-obese children.

There was no overall difference in the survival of patients or their transplanted kidneys between obese and non-obese children, the team reports in the medical journal Pediatrics.

However, obese children between 6 and 12 years old had a three-fold higher risk of dying compared with non-obese recipients. Death was due to cardiopulmonary disease in 27 percent of obese children versus 17 percent of non-obese children.

Overall, graft loss due to blood clots was more common in obese children than the non-obese (19 percent versus 10 percent).

The researchers urge pediatricians to “educate families on the potential risks of excessive weight gain during dialysis and after kidney transplantation.”

SOURCE: Pediatrics, February 2005.