High altitude health: Listen to your heart
August 23, 2012
When it comes to measuring good heart health, doctors in the region often refer to the unofficial Summit Country Treadmill Test – the unfortunate reality that living at altitude or visiting our mountain towns tends to exacerbate current health issues or bring out previously unidentified ones. Worldwide, more than 140 million people live above 8,200 feet (mostly in the Andes and Asia). Compared with acclimatized newcomers, native Andean and Himalayan populations have better oxygenation at birth, increased heart and lung volumes throughout life and a higher capacity for exercise.
Locally, my medical practice includes a lot of older people and, overall, we have a healthy population of seniors in Summit County. They are a self-selected group: Those who cannot tolerate the altitude simply don’t stay here. I was sad to say good-bye to several longtime friends and clients recently based on their deteriorating health.
Altitude affects a number of different health conditions. Perhaps the most important thing to understand is that anything that causes oxygen depreciation and decreased blood flow can result in both short- and long-term problems.
My clients in their 50s and 60s often have coronary artery disease (a narrowing of arteries that reduces blood flow to the heart). This can create additional strain on the heart during exercise, especially in cold weather. I also see patients with diastolic heart dysfunction, which can eventually lead to heart failure. At stage one, I call this “tired heart muscle,” and it can be prevented by maintaining fitness as we age. For overall heart health, common sense prevails: eat healthy, enjoy moderate exercise and find social support among family and loved ones in the community.
For visitors, some advance preparation may make a visit more enjoyable, as just about anyone can get altitude sickness if they ascend too quickly. In particular, people with heart conditions ranging from uncontrolled arrhythmias to congestive heart failure – along with those diagnosed with chronic obstructive pulmonary disease (advancing emphysema and repeated bronchitis) should always check with their physician before planning a visit above 9,000 feet.
A baseline level of fitness will help anyone planning to be active at high altitude. An overnight stay at an intermediate altitude like Denver, good hydration, exercising gently for the first day or two, avoiding excessive alcohol and limiting the use of benzodiazepines like valium or clonazepam which suppress breathing rates can all be helpful.
A drug called Acetazolamide (Diamox) taken 24 hours prior to arrival and for the first two days can be effective at preventing altitude sickness. It stimulates breathing, raises blood oxygen levels and increases urination (which decreases the fluid accumulation that can strain the heart and lungs).
And there is also good news: Researchers at the University of Colorado School of Medicine found that people living at higher altitudes have a lower chance of dying from ischemic heart disease and tend to live longer than others. It may be that lower oxygen levels turn on certain genes which may change the way heart muscles function. These genes may also produce additional blood vessels that create new highways for blood flow into the heart. A second explanation could be that increased solar radiation at altitude helps the body better synthesize vitamin D, which has also been shown to have beneficial effects on the heart and some kinds of cancer.
The study determined that of the top 20 counties with the highest life expectancy, 16 were located in Colorado and Utah at a mean elevation of 5,967 feet above sea level. Compared to those living near sea-level, the men lived 1.2 to 3.6 years longer and women enjoyed an extra 0.5 to 2.5 years.
Decide how you will spend this extra time. Take care of your heart whether you live at high altitude (or if you are a lowlander visiting this mountain paradise). We’d rather find you exercising in the sunshine than unexpectedly taking the Summit County Treadmill Test.
Dr. Charles Lackey has practiced family medicine in Summit County since 1977. He sees clients with all general health concerns at High Country Healthcare’s Frisco office, specializing in medicine throughout the aging process. His work in emergency rooms in Leadville, Denver and Summit County has netted long-term experience in treating altitude illnesses.
Dr. Charles Lackey will lead this week’s Walk with a Doc to discuss Altitude and Heart Health. Meet at 9 a.m. Saturday outside the Medical Office Building next to the Summit Medical Center. For details, visit http://www.HighCountryHealth.com.