Children with chronic kidney disease who are very young and/or Hispanic have a greater chance of being shorter than other youngsters, according to a study done in part by the University of Alberta.
The study, which drew its findings from patient information gathered by the North American Pediatric Renal Transplant Cooperative Studies, revealed that age, race, the cause of the kidney failure and the amount of residual kidney function were associated with short stature in children with renal kidney disease.
The data of 5,615 child patients registered in a chronic renal failure registry between 1994 and 2004 was reviewed by Dr. Verna Yiu, an associate professor of pediatrics at the University of Alberta in Edmonton, Canada and fellow researchers from the University of Texas Southwestern Medical Centre, the Children's Medical Centre of Dallas, University of North Carolina and the EMMES Corporation.
The results were published recently in Pediatric Nephrology.
Of the more than 5,600 patients studied, 36.9 per cent had impaired height growth. Of those, 44.4 per cent were Hispanic, 36.1 per cent were Caucasian and 31.9 per cent were black. Younger children aged zero to 12 years also had lower height growth than children 12 and older. As well, children with congenital renal disease, as opposed to those who acquired the disease, had the lowest rate of height growth. Overall, more than one-third of children with kidney disease met the criteria for short stature.
The researchers are unsure as to why growth is delayed for the first two years of life in children with kidney disease, but believe nutrition and the body's losses of electrolytes play roles.
Ethnicity also appeared to play a role, though standardized norms for height may not take into account natural height differences among ethnic groups, Yiu said. The majority of children in the study with acquired renal disease appeared to be black (39 per cent) versus 17 per cent for the remainder of the registry's ethnicity.
Another factor which affects height is congenital kidney disease. "Children who have kidney disease from birth will have more long-term effects on growth, versus an older child who attains normal height prior to becoming ill," Dr. Yiu said. As well, the more severe the renal failure is, the more a child's growth is hampered by the worsening effects of kidney disease, she noted.
Despite recent advances in managing children with chronic kidney disease, growth remains suboptimal, so it's important determine what factors play a role, said Dr. Yiu.
"By identifying the factors that contribute to short stature in these children, we hope to be able to address the issues early on so that the growth failure can be treated and corrected in appropriate ways such as intensive nutritional programs and therapies such as growth hormone," Dr. Yiu said.