Exposure to secondhand smoke may lead to worsening of pediatric kidney disease.
In adults with chronic kidney disease (CKD), cigarette smoking is associated with an increased risk for CKD progression and transplant failure. Now, a first-of-its-kind study by researchers at Dayton Children’s Hospital and Johns Hopkins University has found a possible similar effect in children with kidney disease who are exposed to secondhand smoke.
The study of 366 children aged 1 to 16 years is the first study of the effect of secondhand smoke exposure in CKD, according to lead researcher Abiodun Omoloja, M.D., associate professor of pediatrics at Boonshoft School of Medicine and attending pediatric nephrologist at Dayton Children’s.
“Within the study population of children with CKD, the researchers found that 22 percent had been exposed to secondhand smoke. They also discovered that exposure to secondhand smoke was associated with higher presence of proteinuria (an abnormal amount of protein in the urine), which is a strong risk factor for CKD progression,” Omoloja says.
The researchers were able to identify children’s exposure to secondhand smoke by testing for the presence of cotinine, a metabolite of nicotine that shows up in the urine.
The study was published last spring in Pediatric Nephrology, the journal of the International Pediatric Association. The research was funded by the Dayton Children’s Foundation.
Researchers were “very surprised” at the relatively high percentage of children exposed to secondhand smoke, says researcher Derek Ng, Sc.M., of the Johns Hopkins Bloomberg School of Public Health Department of Epidemiology. “Twenty-two percent is very high, considering the known adverse effects of smoking and the health status of this population.”
Going forward, the researchers want to learn more about the causative link between secondhand smoke and the worsening of pediatric kidney disease, using this rich dataset, Ng says.
The Dayton Children’s-Johns Hopkins study represents a significant contribution to understanding the adverse effects of second - hand smoke on children, says Karen Wilson, M.D., an associate professor of pediatrics at Children’s Hospital Colorado and the University of Colorado-Denver.
“Many people think that secondhand smoke is only associated with respiratory illness,” she said. “So it is very helpful to have this data showing a strong association between secondhand smoke and kidney disease. It highlights some of the systemic effects of secondhand smoke exposure in addition to respiratory problems.
“Going forward, it will be important to continue to do research on the medical effects of secondhand smoke in kids because the physiology of all these may be similar,” Wilson says. Increasing the understanding of these effects “will help us better protect children, both by helping families quit smoking and also by finding treatments for children who have been exposed to secondhand smoke.”