Kidney stone risk doubles with just mild obesity
New findings show that people who are just mildly obese double their chances of developing kidney stones – a painful urologic condition that accounts for 3 million doctor visits annually according to the NIDDK. In the past the risk of developing kidney stones was thought to be linked to higher body mass, but new findings show the risk is the same for those who are mildly or morbidly obese.
Brian R. Matlaga, assistant professor of urology at the Johns Hopkins University School of Medicine and director of stone diseases and ambulatory care at Hopkins' James Buchanan Brady Urological Institute explains "The common thinking was that as weight rises, kidney stone risk rises as well, but our study refutes that. Whether someone is mildly obese or morbidly obese, the risk for getting kidney stones is the same."
The most common kidney stones develop from a combination of calcium and oxalate or phosphate that come from diet and substances in the body that combine to form crystals in the urinary tract. If the crystals are small they pass through the kidneys, through tubes called ureters that empty urine in the bladder and through the urethra, causing no symptoms. But when kidney stone are larger, they can cause severe pain and require medical treatment to eradicate. A type of kidney stone called struvite can cause infection.
Also, according to the NIDDK, kidney stone prevalence has steadily increased in the past 30 years. Predicting who will develop kidney stones has been difficult, but the new research may shed some insight into who is at risk. The scientists explored 95,598 people who completed a health risk assessment survey, taken from a national insurance database to find the link between just mild obesity and the increased risk for developing kidney stones.
When researchers analyzed databases for the current study they found that 4.9 percent of individuals who were even mildly obese had been diagnosed with kidney stones compared to 2.9 percent of non obese individuals.
The researchers are not exactly sure why even mild obesity contributes to kidney stone development. It may be a combination of metabolic factors, or type of foods consumed that might include more salt in the diet. The scientists plan more studies to sort out exactly why obesity, mild or severe, leads to the increased risk of developing kidney stones.