Kidney stones are a common condition in the United States affecting about 9 percent of Americans. Every year, roughly 500,000 patients are admitted into emergency rooms because of kidney stones. While the prevalence of the condition has risen over the years, increasing from 1-in-20 people in 1994 to 1-in-11 in 2012, the trend is expected to continue, both in broader geographic coverage and in greater numbers due to extreme temperatures associated with climate change. Higher temperature leads to dehydration, which in turn contributes to increased concentrations of dissolved salts and other substances in urine. When urine is super-saturated, it allows kidney stones to develop.
Low Urine Volume
The risk of kidney stones increases with decrease in urine volume. Caused by poor fluid intake or fluid loss (dehydration) due to hard exercise, living or working in a hot place, low urine volume means there is less fluid available to dissolve salts and other urine constituents. In turn, the urine becomes darker in color, more concentrated and easily forms stones. In fact, a urine volume below 1 liter per day is associated with 10 percent of all recurrent kidney stones while urine volume below 1.5 liters per day is linked with the formation of many recurrent and first-time kidney stones. Low urine volume due to chronic dehydration, defined as a history of prolonged exposure to heat, is the main cause of 20 percent of all incidents of kidney stones.
Effect of Warmer Temperatures
Cases of kidney stones typically increase shortly after episodes of hot weather, hitting a peak within three days of exposure to extreme heat. According to a recent study published in the Environmental Health Perspectives, daily increase in average temperatures leads to increased risk of formation of kidney stones. Another study published in 2008 by the National Academy of Sciences also reported that about 70 percent of Americans are under high risk of kidney stones due to warmer temperatures compared to just 40 percent of Americans at risk in 2000. The number of cases of heat-related kidney stones is projected to increase to up to 2.2 million by 2050.
Increase in ambient temperatures results in increased fluid losses through the skin. As more water is lost in sweat and less in urine, salts can build up in urine resulting in stones. Even in cold weather, dehydration occurs in the warm and dry indoor air without being noticed. And since dehydration often occurs without being noticed, it is a bigger factor in kidney stone formation in many patients. For instance, in drier climates, people lose a lot of water through sweat without realizing it and face a greater risk of kidney stone formation.
Are you or your loved one suffering from the symptoms of kidney stones? Would you like to receive world-class, safe, prompt and effective treatment for kidney stones? Or are you looking for the most comprehensive and accurate information on prevention, diagnosis and treatment of kidney stones? Then Advanced Urology Institute is the right place for you. At AUI, we offer patient-friendly and multidisciplinary urology services for a wide range of problems including kidney stones. For more information, visit the “Advanced Urology Institute” site.