No matter what climate you live in,
you’re more likely to die of heart-related issues in the winter,
according to research presented at the American Heart Association’s
Scientific Sessions 2012.
“This was surprising because climate was
thought to be the primary determinant of seasonal variation in death
rates,” said Bryan Schwartz, M.D., lead author of the study.
Lead investigator Dr Bryan Schwartz
(Good Samaritan Hospital, Los Angeles, CA), along with senior
investigator Dr Robert Kloner (University of Southern California,
Los Angeles), analyzed 2005-08 death certificate data of individuals
living in hot climates (Texas, Georgia, and Maricopa Country in
Arizona), moderate climates (Los Angeles and western Washington),
and cold climates (Massachusetts and Pennsylvania).After doing so,
they calculated the seasonal variation of circulatory death around
the mean for each location.
In all areas, total and “circulatory”
deaths rose an average 26 percent to 36 percent from the summer low
to the winter peak over four years. Circulatory deaths include fatal
heart attack, heart failure, cardiovascular disease and stroke.
"Each location in the wintertime had
approximately an 18% increase over the average, and in each location
in the summertime there was an approximate 10% to 12% decrease from
the average yearly death rate," said Schwartz. "Beyond that, the
lines in the springtime come down very close to each other, and in
the fall they increase almost together, are almost superimposed on
each other. We found this to be surprising. We thought that colder
climates with a colder winter would have a greater increase in
mortality in the wintertime or have a prolonged increase in the
wintertime, but that's not what we found."
Seasonal patterns of total and cardiac
deaths were very similar in the seven different climate patterns.
Death rates at all sites clustered closely together and no one site
was statistically different from any other site.
Researchers didn’t design the analysis
to determine specific causes that might drive heart-related deaths
up in winter. Schwartz hypothesized that colder weather might
increase vessel constriction and raise blood pressure.
“In addition, people generally don’t
live as healthy in winter as they do in summer,” said Schwartz, now
a cardiology fellow at the University of New Mexico in Albuquerque.
“They don’t eat as well and don’t exercise as much.”
However, “people should be extra aware
that maintaining healthy behaviors is important in winter,” he said.
For more information about cold weather
and cardiovascular disease, visit
http://www.heart.org/
(MDN) | 
