As the population of obese Americans has increased over the last two decades, so have cases of kidney stones.
In fact, the number of cases between 1994 and 2010 nearly doubled.
“While we expected the prevalence of kidney stones to increase, the size of the increase was surprising,” said Dr. Charles D. Scales, Jr., of the UCLA School of Medicine. “Our findings also suggested that the increase is due, in large part, to the increase in obesity and diabetes among Americans.”
Because the survey also asks about other health conditions, and includes measurement of height and weight, the researchers were able to identify associations between kidney stones and other health conditions. The results suggest that obesity, diabetes, and gout all increase the risk of kidney stones.
It's another reason to put down that donut, eat healthier and start getting more exercise. And there may be a lesson here for health care providers.
“People should consider the increased risk of kidney stones as another reason to maintain a healthy lifestyle and body weight,” says, MD, MPH, senior author, principal investigator within RAND Health for the Urologic Diseases in America project and associate professor of urology, David Geffen School of Medicine at UCLA. “But physicians need to rethink how to treat, and more importantly, prevent kidney stones,” said Dr. Christopher S. Saigal, an associate professor at UCLA's medical school.
Treating underlying cause
The researchers note that current practice for kidney stone treatment is to focus just on the stones. Yet helping patients maintain a healthy diet and body weight, researchers say, can reduce the number of patients with kidney stones.
“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,” said Scales. “This is how we currently treat people with kidney stones. We know the risk factors for kidney stones, but treatment is directed towards patients with stones that cause pain, infection, or blockage of a kidney rather than helping patients to prevent kidney stones in the first place.”
Kidney stones can form when urine contains too much of certain substances. These substances can create small crystals that become stones. The stones take weeks or months to form. In addition to being overweight and having diabetes, a significant risk factor for kidney stones is not drinking enough fluids, according to the National Institutes of Health. Kidney stones are more likely to occur if you make less than one liter of urine a day. That's slightly more than a quart.