Does Cold Weather Increase The Risk Of Stroke?
A stroke occurs when a blood vessel carrying oxygen-rich blood to the brain is either blocked or ruptures. High blood pressure, smoking, obesity, excessive alcohol consumption, and a history of stroke are all known risk factors for stroke. However, does a drop in temperature during the chilly winter months lead to an increase in stroke risk? Let’s find out.
What is a stroke?
A stroke happens when a blood vessel in the brain bursts and bleeds or when there is a blockage in the blood supply to the brain. The rupture or obstruction prevents blood and oxygen from reaching the tissues of the brain. As a result, the brain cells get damaged and start to die within minutes of being oxygen-deprived.
Strokes are classified into three types. They include:
- Ischemic stroke is caused by a blockage in the artery due to a clot or plaque.
- Hemorrhagic stroke is caused by either a ruptured or leaking blood vessel that seeps into the brain tissue and causes an increase in pressure within the brain.
- A transient ischemic attack (TIA), also known as a “mini stroke” is caused by a temporary disruption in the blood supply to the brain. It is caused by a blood clot that usually dissolves on its own. The symptoms and complications of a TIA are less severe than those of an ischemic or hemorrhagic stroke.
What are the symptoms of a stroke?
Your brain is divided into different functional areas, so the symptoms of a stroke vary depending on which part of the brain is affected.
They include the following:
- Aphasia (difficulty or loss of ability to speak)
- Amnesia (memory loss)
- Ataxia (loss of coordination)
- Dysarthria (slurred or garbled speech)
- Diplopia (double vision)
- Muscle weakness on one side of your face
- One-sided paralysis or weakness
- Sudden or partial loss of one or more senses
- Seizures (fits)
- Severe headaches
- Vertigo (a sudden spinning sensation)
Did you know that colder temperatures cause constriction of blood vessels, raise blood pressure, and increase your risk of a stroke?
How do the winter months increase the risk of stroke?
Studies have found a relationship between winter and increased rates of stroke, and it is believed that certain changes in weather could act as triggers for a stroke.
According to a study presented at the American Heart Association International Conference, the risk of hospitalisation due to stroke increases by six percent for every five-degree decrease in temperature.
An increased risk of stroke during the winter months may occur for the following reasons:
- Colder weather causes blood vessels to constrict because of an increase in vasoconstrictors like noradrenaline, which raises blood pressure, a major risk factor for stroke.
- A blockage in a blood vessel to the brain caused by blood clots is one of the main causes of stroke. Cold weather increases the likelihood of platelet aggregation and tilts the balance of clotting and clot lysis, making it easier to clot.
- Humidity is also known to play a major role in an increased stroke risk. High humidity in the atmosphere can cause some people to become dehydrated, increasing the risk of blood clot formation. As humidity rises, so does the stroke risk, with a two percent increase for every five-degree rise in dew point.
- Lack of sunlight exposure and a sedentary lifestyle can both increase the risk of stroke.
- Cold weather also increases the risk of serious systemic infections in the elderly.
Overall, researchers have found a seasonal pattern of stroke rates, which are found to be higher in the winter months and lower in the summer months.
What are the precautionary measures?
Lifestyle changes cannot completely prevent strokes. However, many of these changes can make a significant difference in lowering your risk of stroke.
Some of these modifications include:
- Quitting smoking
Smoking increases blood pressure, reduces oxygen levels in the blood, and promotes the formation of blood clots.
- Limiting alcohol use
Heavy alcohol consumption can raise your blood pressure, increasing your risk of stroke.
- Maintaining moderate weight
Overweight and obesity put you at risk for other health conditions and increase the risk of stroke.
- Getting regular checkups
Pre-existing health conditions such as high blood pressure, diabetes, and high cholesterol levels require periodic follow-ups to reduce the risk of stroke.
Taking all these measures will help you stay in better shape and prevent the risk of developing a stroke.
Furthermore, it is critical to keep a close eye on family members, friends, and neighbours who are at a high risk of stroke during extreme weather, particularly during the winter. They should be closely monitored in terms of what they eat, and their sodium intake should be limited.
How do you identify a stroke?
Remember to think FAST when recognising the warning signs of a stroke:
- F (Facial Deviation)
As the patient smiles, look for signs of drooping on one or both sides of their faces, which is an indication of muscle paralysis or weakness.
- A (Arm Weakness)
Muscle weakness on one side is common in stroke patients. Request that they raise their hands. If they have one-sided weakness (and they did not have it previously), one arm will remain higher while the other will drop downward.
- S (Speech Disturbance)
Strokes frequently cause people to lose their ability to speak, causing them to slur their words or have difficulty choosing the right words.
- T (Time To React)
Get help right away because receiving treatment at the right time is very critical. If possible, keep track of symptoms as it would help the healthcare professional in determining the best course of treatment if they know when the symptoms first appeared.
Stroke is a major cause of mortality and morbidity in India, accounting for the fourth leading cause of death and the fifth leading cause of disability.
Knowing the signs and symptoms of a stroke, as well as modifiable risk factors, may help reduce the risk of stroke and the long-term effects of a stroke. This new correlation could have an impact on how at-risk patients and caregivers react to weather changes and take appropriate precautions.
- Stroke in India: A systematic review of the incidence, prevalence, and case fatality
- Stroke Epidemiology and Stroke Care Services in India
- Winter Weather and Stroke Risk
- Everything You Need to Know About Stroke
About Author –
Dr. Mohan Krishna Narasimha Kumar Jonnalagadda, Consultant Neurologist, Yashoda Hospitals - Hyderabad
MBBS, MD (Internal Medicine), DM (Neurology)