More Kidney Stones with Climate Change?
Just as canaries were the sentinels for coal miners until
the late twentieth century, the
city of Milwaukee may be a harbinger of things to come in Midwestern urban
areas as twenty-first century climate change brings higher temperatures, more
weather extremes and more hospital patients.
Among other things, researchers are finding more renal
diseases in hotter weather. We knew that rising heat brings itchier poison ivy and more mosquitoes further north and
higher up. But kidney stones?
The deadliest heat wave on record struck Europe in 2003, when
27,000 people died of heat-related
afflictions. Unrelenting high
temperatures have produced more cases of
dehydration, heat stroke, asthma and respiratory ills and death,
world-wide, especially among the very old, the very young and the chronically
Now scientists examining 17 years of Milwaukee hospital and
acute care admissions have identified several illnesses
and conditions that seem especially heat-sensitive, including diabetes, urinary
tract and renal disease, kidney stones,
respiratory ills, accidents and suicides. Researchers at the University
of Wisconsin-Madison, Purdue University and the National Center for Climatic
Research studied admissions from 1989 through 2005. They even discovered
temperature thresholds beyond which the numbers of certain illnesses
increase. For instance, for every
two degrees the mercury rises above 85 degrees F, hospitalizations for diabetes and kidney disorders rise 13
percent and admissions for endocrine diseases increase by nine percent.
Accidents and suicide attempts rise by three percent when the temperature rises two degrees above
81 degrees F. The study, by Jonathan Patz, director of
the UW-Madison Global Health Institute,
and colleagues, is published in the journal Climatic Change.
A California study comparing hospital
admissions and temperature in nine counties showed that even without heat
waves, admissions for several illnesses spike when the mercury rises. The study
found that every ten degree rise in temperature between May and September
brought about a 400 percent increase in admissions for heat stroke, seven
percent for kidney failure, four percent for pneumonia, and among five to
18-year-olds, a 21 percent increase for intestinal disease caused mostly by
food born illness.
The Daily News and Analysis, a print and broadcast company
in India, reported a 40 percent increase in kidney ailments last
summer. A team of U.S. scientists predicted in 2008 that kidney stones will become more prevalent
with warmer weather in the south and southeast and that anticipated higher
temperatures could bring millions more cases of kidney stones and $1.3 billion
in increased medical bills by 2050.
Excessive water loss caused by heat exposure can lead to diarrhea and
electrolyte imbalance, which can cause heat induced kidney ailments and
exacerbate chronic kidney conditions.