Nephrolithiasis has become a more common occurrence among young patients, with the greatest increase in incidence among individuals aged 15 to 19 years, women, and African Americans, after years of being an issue thought to affect middle-aged white men, according to a report published online ahead of print January 14 in the Clinical Journal of the American Society of Nephrology.

Lead author Gregory E. Tasian, MD, MSc, MSCE, and fellow investigators studied data on an at-risk population of 4,625,364 people and found that 152,925 patients received emergency, inpatient, or surgical care for nephrolithiasis. Overall, the annual incidence of kidney stones increased 16% between 1997 and 2012. The risk of nephrolithiasis doubled during childhood regardless of gender, and there was a 45% increase in the lifetime risk for women. Considering age categories, the researchers found the greatest increase in incidence was among those aged 15 to 19 years, at 26% every 5 years. The highest rate of increase was among adolescent females, and nephrolithiasis was more common among females than males aged 10 to 24 years in every year studied. After age 25, kidney stones became more common among men, the researchers found. Among African-Americans, the incidence of nephrolithiasis increased 15% more than whites every 5 years.