Increasing temperatures could raise the prevalence of kidney stones, researchers reported in Proceedings of the National Academy of Sciences (2008; 105:9841-9846). Theorizing that global warming will encourage dehydration, they expect an additional 1.6 million to 2.2 million kidney stone cases by 2050, with the incidence rising as much as 30% in some places.
The team based its findings on global warming data from the Inter-governmental Panel on Climate Change's 2007 Fourth Assessment Report and two studies that reported kidney stone rates in various geographic regions. The researchers correlated regional rates with local mean annual temperatures and created two mathematical models relating temperature to kidney stone risk. One foresees a concentration of new cases in the southern half of the United States; the other predicts a significant rise in the upper Midwest.
“This study is one of the first examples of global warming causing a direct medical consequence for humans,” said investigator Margaret Pearle, MD, PhD, professor of urology at the University of Texas Southwestern Medical Center in Dallas.