Thin air a boon for life expectancy

Borrowed from Allen Best of the Durango Telegraph

TELLURIDE – Is living at higher elevations actually healthier? A new study suggests that’s the case.

The study found that 16 of the 20 counties with the highest life expectancy were in Colorado and Utah, at a mean elevation of just under 6,000 feet. Compared with those living near sea level, men lived 1.2 to 3.6 years longer. Women lived 0.5 to 2.5 more years than their sea-level counterparts.

The study was conducted by the University of Colorado School of Medicine and Harvard School of Global Health. Researchers analyzed death certificates from every county in the United States over the course of four years.

Taken alone, said Dr. Peter Hackett, executive director of the Institute for Altitude Medicine, living at higher elevations is no panacea. “You can’t smoke and not exercise and come here to live longer,” he told The Telluride Watch.

A study of this sort needs to account for variables among those living at altitude. For example, do they smoke less than their counterparts at sea level? Are they less obese? For the most part, the researchers were able to deliver apples-to-apples comparisons.

“It’s not a perfect study, but they collected as much data as they could,” said Hackett, who has climbed Mt. Everest twice and spent many seasons ministering to climbers on Denali, North America’s highest peak. “As it turns out, there is something about the lack of oxygen at high altitude that is actually good for the heart.”

What’s going on? “Lower oxygen levels turn on certain genes, and we think those genes may change the way heart muscles function,” said Benjamin Honigman, professor of emergency medicine at the University of Colorado. “They may also produce new blood vessels that create new highways for blood flow into the heart.”

Hackett said that studies show that South Americans living at 14,000 feet have more blood vessels in their hearts than those living at low elevations. When the heart has more blood vessels, he said, blood is able to flow into the heart more effectively, especially if there is a clot.

“This wasn’t done at 8,000 feet. It was done at 14,000 feet, but there is no reason to think that people living at 8,000 feet wouldn’t have some of that,” Hackett toldThe Watch.

One thing the study did not sort out is how long someone must live in thinner-aired elevations for the benefits to the heart to accrue. Hackett said he believes somebody born and reared at high altitude has an advantage over someone who moved to a place like Telluride, which is just below 9,000 feet in elevation, at the age of 60.

The study also found that living at elevations of more than 4,900 feet has adverse effects on those with compromised lungs, including those with emphysema and chronic bronchitis.