Prevalence of Kidney Stones Nearly Doubles

    • June 7, 2012

Another chronic condition—kidney stone disease—is on the rise.

The prevalence of kidney stones nearly doubled since the mid-1990s, according to a new study by Charles D. Scales, Jr., MD, a Robert Wood Johnson Foundation (RWJF)/U.S. Department of Veterans Affairs Clinical Scholar (2011-2013) in the departments of urology and medicine at the University of California at Los Angeles.

One out of every 11 people—or nearly 10 percent of the population—developed a kidney stone between 2007 and 2010, Scales and his co-author found in a recent study published in European Urology. In 1994, the rate was one out of 20, or 5 percent of the population.

The increased prevalence of kidney stones—small “pebbles” comprised of chemicals in urine—is likely related to dietary and lifestyle changes that have led to increasing rates of obesity, diabetes, and gout—a kind of arthritis that causes joint pain, Scales says. “We know from physiologic data that these diseases essentially change the composition of urine in ways that promote the formation of kidney stones,” Scales says. “The increasing prevalence of kidney stones is really related to diet and lifestyle, just like so many other conditions.”

Other factors could also be contributing to the rise of kidney stones, Scales and his co-author, Christopher S. Saigal, MD, MPH, principal investigator within RAND Health for the Urologic Diseases in America project, write. Changes in atmospheric temperature could be causing more dehydration, a risk factor for stones. The incidence of stones, meanwhile, increases with age, so an aging population could also be playing a role. Meanwhile, the use of radiologic imaging is on the rise, which could mean that providers are finding and diagnosing more asymptomatic stones. But those explanations do not explain the entirety of the increase, Scales says.

For the study, Scales and Saigal examined data collected from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2010. Men continue to be more likely than women to experience kidney stones, but both men and women saw higher rates of stones over the two-decade period, they found. The increased prevalence of stones affected all racial and ethnic groups examined, but the rise was sharpest among African Americans and Latinos.

The findings have important implications for health and health care, Scales says. Individuals, he notes, should maintain a healthy lifestyle and body weight to prevent kidney stones, and the health care system needs to take a different approach to treating and preventing kidney stones.

Currently, health providers treat kidney stones when they cause pain, infection or blockage, Scales says—but providers need to take a more preventative approach. “Imagine that we only treated people with heart disease when they had chest pain or heart attacks, and did not help manage risk factors like smoking, high cholesterol or high blood pressure. This is how we currently treat people with kidney stones.”

Lack of Awareness

Part of the problem, Scales says, is a lack of awareness about the disease. Kidney stones get less attention than more life-threatening, weight-related conditions like heart disease and diabetes. But they exact a heavy medical and economic cost. In addition to extreme pain (often compared with the pain of childbirth), kidney stones take a heavy economic toll in terms of health care costs and workplace absenteeism in a primarily working age population.

“Kidney stones are more prevalent than conditions like heart disease and stroke, and are more costly among people under 65 than prostate cancer or other urologic conditions like benign prostate enlargement,” he says. “We need to pay more attention to the disease and work to prevent stones from recurring.”

The prevalence of kidney stones is likely to continue to rise in light of the growing obesity epidemic, Scales adds. “We need to make sure people have access to plenty of drinking water and eat a low-sodium, low-calorie, low-meat diet. If we do that, we’ll minimize the risk of kidney stones and we’ll also help prevent heart disease, diabetes and stroke down the line.”