In a marked increase, kidney stones, a painful condition that historically mainly affected middle-aged white men, are growing more common in the U.S. Perhaps surprisingly, that rise is particularly steep among adolescent, female, and African-American populations, according to a new study from The Children’s Hospital of Philadelphia.
The study, analyzing age, race and sex characteristics among children and adults in South Carolina, was led by Gregory E. Tasian, MD, MSc, MSCE, a pediatric urologist and epidemiologist at CHOP and assistant professor at the Perelman School of Medicine at the University of Pennsylvania, and published online Jan. 14 in the Clinical Journal of the American Society of Nephrology.
How and why the rates of kidney stone increase particularly affected adolescents (4.7 percent per year), females (3 percent per year), and African-Americans (2.9 percent per year), has important implications for parents and pediatric specialists.
Who is at the most increased risk of kidney stones: Teen girls.
The highest rate of increase in kidney stones was among adolescent females, Dr. Tasian’s team found. In any given year, stones were more common among females than males age 10 to 24 years. After age 25, kidney stones became more common among men.
Between 1997 and 2012, the risk of kidney stones doubled during childhood for both boys and girls, while there was a 45 percent increase in the lifetime risk for women.
Among African-Americans, the incidence of kidney stones increased 15 percent more than in whites within each five-year period covered by the study.
Why it matters for children’s health: Pediatric providers may not be prepared to optimally test, identify, and treat youth with kidney stones.
“The emergence of kidney stones in children is particularly worrisome, because there is limited evidence on how to best treat children for this condition,” Dr. Tasian said. “The fact that stones were once rare and are now increasingly common could contribute to the inappropriate use of diagnostic tests such as CT scans for children with kidney stones, since healthcare providers historically have not been accustomed to evaluating and treating children with kidney stones.”
In addition, Dr. Tasian noted that the increased incidence among adolescent girls is concerning because kidney stones are associated with a higher risk of chronic kidney disease, cardiovascular and bone disease, particularly among young women.
How more young people are getting kidney stones: Many possible factors, including diet, hydration, and temperature, could contribute.
Among the possible factors for the rise in kidney stones Dr. Tasian and his co-authors noted were poor water intake and dietary habits, such as an increase in sodium and a decrease in calcium intake. However, their study did not examine dietary differences. In addition, dehydration, which promotes the growth of kidney stones, is related to both poor water intake and higher temperatures. Dr. Tasian led a 2014 study that showed a link between higher daily temperatures and an increase in patients seeking treatment for kidney stones in five U.S. cities, a link that may be a consequence of climate change.
What can be done about it: More research on interventions and prevention is needed for patients with kidney stones who are not middle-aged white men. Dr. Tasian noted that the increasing incidence of kidney stones among young people, females, and African-Americans highlights the needs for more studies on optimal interventions to decrease recurrence in these groups. Most prior clinical trials of medications to decrease stone recurrence have been conducted among middle-aged white men. It is possible that the efficacy and the effectiveness of treatments may vary by age, sex, or race.
Additionally, he noted that little research has been done to identify ways to change behavior, such as increasing fluid intake, among either children or adults with kidney stones. Dr. Tasian currently is investigating barriers to water intake among adolescents with kidney stones and will be opening a randomized clinical trial to examine the effectiveness of interventions using mobile devices to increase water intake and decrease stone recurrence risk.
The National Institutes of Health (grants DK106428, DK093556 and DK078737) supported this research. Co-authors with Dr. Tasian were Michelle E. Ross, Lihai Song, Ron Keren, Michelle Denburg, Lawrence Copelovitch and Susan Furth, all from CHOP; David J. Sas, from the Mayo Clinic; and Christopher S. Saigal, from the University of California, Los Angeles.
For more information, see the CHOP press release.