Stone disease: Not just a problem in men anymore?

San Antonio--The prevalence of women being discharged for stone disease has increased in recent years, according to research presented at last month's AUA annual meeting. The rate discharges for men with stone disease over the same period increased slightly for renal calculi and decreased in the case of ureteral calculi.

"There's a significant amount of evidence which indicates there may be some changes going on," said lead author Charles D. Scales, Jr, MD, a research associate in the division of urology at Duke University Medical Center, Durham, NC. "There are a number of lifestyle and dietary factors that clearly impact the presence of stone disease."

And I believe that these features may be causing these underlying changes we're seeing in the data."

Overall, the number of ureteral stone discharges stayed fairly constant, while renal stone discharges increased by 18.9%. For ureteral calculi, discharges for males de-creased by 9.8%, while discharges for females increased by 19.2%. For renal calculi, discharges for males increased by 12.2%, and discharges for females increased by 21%.

Remarkably, the number of discharges for renal calculi was equal among males and females in 2002.

The researchers also analyzed population-adjusted discharge rates. They found a slight, statistically insignificant decrease in ureteral calculi.

"Population-adjusted renal calculi discharges, however, increased by more than 14% during the study period," Dr. Scales said.

"The increase in renal calculi discharges was accounted for by a small in-crease in the rate of discharges for males, while females had a 21.5% increase in the rate of discharges for renal calculi."

The obesity epidemic in America may be related to these changes in stone epidemiology, according to Dr. Scales. (Also see, Urology Times, March 2005.)

Data from the CDC shows that the combined prevalence of overweight and obesity is, like stone disease, increasing faster in women than men, and other investigators demonstrate that obese women may be at even higher risk for stones than obese men," he said.

Investigation of the relationship between diet, lifestyle, gender, and stone disease risk would be useful in studying these findings further, according to Dr. Scales.

"Further investigation is required to confirm these changes and to identify the causes of this apparent shift in the epidemiology of stone disease," he said.