Dr. VIPUL GUPTA
Every year it has been seen that the dipping temperatures are responsible for a rise in number of cardiovascular problems, among which stroke is one of critical illness. This year, the temperatures have started to take sudden dip and is expected to be so throughout the New Year period especially in the Northern part of the country.
Stroke, which can be because of blockage causing paralysis or burst of blood vessel leading to bleeding, is seen more commonly during the winters. This is an important problem, as stroke is recorded to be the third leading cause of death and disability and WHO estimates suggest that one in four people may suffer stroke over a lifetime.
The neuro intervention & stroke team at Artemis hospital has witnessed more incidences of stroke in the winter months. It is particularly worrisome that many young patients with uncontrolled blood pressure have developed bleeding in the brain during this vulnerable period. Probably the sudden increase in blood pressure in cold weather has played a role in these particular patients.
Various studies conducted in Japan, Korea, USA and China also suggests that there are more chances of stroke during the winter months. Several studies suggest that during extreme cold conditions, the risk of getting a stroke attack increases by 80% particularly when temperature dips below 15 degrees Celsius. Last year a study of around 56000 stroke deaths (over a decade) in Sao Paulo, Brazil found that falling temperatures may increase the number of deaths from stroke, particularly among people over 65 years.
Another German study published in the same year in the European Journal of Epidemiology discerned that for every 2.9-degree Celsius drop in temperature over 24 hours, strokes increased 11 percent, and at higher rates for those already at risk. In the year 2016, a study published in the Journal of Stroke and Cerebrovascular Diseases examined nearly 1.72 Lakh ischemic hospitalizations in the United States and found that most of them occurred in cold average temperatures and when temperatures fluctuated significantly. Taking care of this issue is very important because this may lead to more chances of this deadly disease.
Why is winters a potential season for the rising incidences of stroke?
One of the prime reasons can be attributed that during the cold seasons the blood vessels constrict, which leads to the increase in blood pressure, which is a major risk factor for stoke. Also, there are various changes in the chemical balance in our body during the winters that increases the chances of clotting. Probably the reason number of stroke cases go up by 11 per cent during winters.
Other factors include prevalence of unhealthy habits like too much eating and drinking combined with decrease in physical activity. And in countries like India, High pollution levels and depleting Air Quality Index (AQI) clubbed with winter smog also aggravates the condition.
Though anyone is susceptible to get a stroke, however, people with existing cardiac problem, high blood pressure problem, smokers, obese and elderly need to be watchful as with the weather getting cold, they are the ones more vulnerable to get a stroke. In fact, such patients have a higher risk of even dying from heart disease as well.
Reducing the risk of stroke in winters
In order to curb down the chances for stroke and other cardiovascular events, the most vulnerable groups need to take sensible precautions to ensure and minimize the after-effects of extreme cold weather. It is strongly recommended to regularly monitor your blood pressure during this changing weather, particularly those who are already hypertensive. And even with mild changes or rise in the blood pressure, one need to immediately consult the doctor who can prescribe an adjustment in the medications.
It is also advised to keep warm and avoid sudden exposure to severe cold temperatures as the risk of stroke remains for many days after the exposure. The elderly are advised to keep warm and if possible heat the home as well. It is advisable to keep oneself well hydrated and avoid sudden excessive exertion, excessive drinking or unhealthy eating.
(The Author is chief of Neurointervention and Co-chief of Stroke unit, Artemis hospital)