Your blood pressure and the weather

The temperatures are going down, but your blood pressure is going up. Is this logical?

It is, according to a French research study which observed that blood pressure varies with the season. The data of the study is based on measurements on 8,801 French adults older than 65 years and followed up for more than two years.

The study results show “that blood pressure in elderly people varies significantly with the seasons, with rates of high blood pressure readings rising from 23.8% in summer to 33.4% in winter. Blood pressure increases were seen in both the systolic (top) and diastolic (bottom) numbers.” The average systolic blood pressure was 5 mmHg higher in the winter months than in the summer months.

What is more disturbing is that the temperature-related effects on high blood pressure become more pronounced with age, and as observed in this study, in people older than 80 years.

The mechanism behind this seasonal variation is not clear but “possible explanations of the cold weather effect include activation of the sympathetic nervous system (which helps control how the body responds to stress) and release of the hormone catecholamine, which may increase blood pressure by speeding the heart rate and decreasing the responsiveness of blood vessels.”

The findings of the study help shed light on the well-documented seasonal variations in illness and death caused by stroke and aneurysms or rupture of the blood vessels. According to the American Stroke Association, stroke is the number 3 cause of mortality in the US, after heart disease and cancer.

And now that it is winter time in the northern hemisphere, people, especially the elderly should closely monitor their blood pressure. However, the increase in blood pressure in winter time should not actually discourage people from venturing outdoors. The American Stroke Association and American Heart Association encourage physical activity such as walking – even in winter time through the Start! Heart Walk. Connect with other walkers (sole-mates!) in your area using the My Start! Community. Track your walking progress using the free online tool My Start! Online Tracker. The brochure Start! Walking This Winter can give you some basic tips on how to enjoy the winter outdoors without endangering your health.

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