Summer has arrived. It is time for all of those fun summer activities: golf, tennis, hiking, swimming, kayaking and sitting on the beach. Unfortunately, summer poses some unique risks for the heart patient. How does the heat affect the heart? Is vacationing good for cardiac health? If so, what type of vacation is beneficial? These questions and more will be answered!
The extremes of temperature, either very hot or very cold, are known to cause additional stress to the heart patient. It is well known that heat waves cause a surge in deaths and hospitalizations for heart disease. Elderly patients are more prone to dehydration which can lead to low blood pressure and increased blood clotting. In addition, very hot temperatures increase the work load of the heart. These effects can lead to a subsequent heart attack or passing out or congestive heart failure. A recent study showed that for each additional extreme heat day (defined as heat index over 90 degrees) there is a 0.13% increase in deaths from heart disease. This translates to an additional 600 to 700 deaths per year in the US due to the heat. With three times as many heat waves per year now compared to the 1960’s, heat related illness must be taken seriously.
In the absence of a heat wave can a warm summer night be just as risky? Recent research showed that a rise of just 1.8 degrees Fahrenheit in the usual summer-time temperature caused a 3-5% increase in heart related deaths in men aged 60 to 64, but not in men over 65 or in women. It seems that nighttime temperature had a more potent effect than daytime warmth on death and heart disease. The reason for this is not clear. Socio-economic factors are an issue; those without air conditioning would be more vulnerable to warm temperatures. An intriguing theory involves sleep deprivation. Hot summer nights, especially without air conditioning, could lead to more tossing and turning, interrupting sleep patterns with subsequent increase in blood pressure, heart rate and risk for cardiac events.
One way to escape the heat is to go on vacation. Can taking a vacation reduce the risk for cardiac events? The Framingham Heart Study showed that men who didn’t take a vacation for many years were 30% more likely to have a heart attack than men who took a yearly vacation. The same study concluded that women who took vacations once every 6 years were 8 times as likely to have heart disease as those who took more frequent time off. The MRFIT trial followed 12,000 men for nine years. It showed that men who took annual vacations were 21% less likely to die and 32% less likely to die from heart disease. Vacationing may have a direct protective effect on heart health for the following reasons. First, vacationing reduces stress and releases one from job demands. Next vacationing may have restorative effects by promoting social contact with family and friends (“reconnecting”). Lastly, certain types of vacations increase physical activity.
So vacations are good for cardiac health. What type of vacation is beneficial; an active vacation or relaxing on the beach? One study from Austria helps answer the question. It showed that an active vacation involving walking, biking or golfing reduced blood pressure and heart rate and helped improve cardiac function. Therefore, an active vacation may improve cardiac health more than lying in the sun. It seems that physical activity during leisure time (including vacations) is beneficial. How does physical activity during leisure time compare to physical activity at work? The Copenhagen General Population Study followed 104,000 people over 10 years and had an interesting answer to the question. The study found that physical activity during leisure time reduced the risk for cardiac events by 15% and the risk for death by 40% but physical activity at work increasedthe risk for cardiac events and death. They called this the “physical activity paradox”. Why is this? They theorized that leisure time activity was more dynamic, more likely to improve cardiorespiratory fitness and allows sufficient recovery time. Physical activity at work, on the other hand, is more static, monotonous, often occurring with awkward positioning and did not allow for meaningful recovery time.
So as we head into summer, make those vacation plans. Then dust off the golf clubs or hiking boots. Lastly, crank up the air conditioning at night and get a good night’s sleep.
