Dehydration and Stroke Risk: How Are They Linked?

Did you know that stroke is the top cause of long-term disability and the fifth leading cause of death in the United States? Since about 50% of stroke patients are dehydrated, you might wonder how these conditions are linked. 

If you’re concerned about stroke, it’s important to seek advice from a board-certified neurologist, like Risa Ravitz, MD, at Modern Migraine MD. Dr. Ravitz sees patients in Manhattan, NYC, Toms River, New Jersey, Aventura, Florida, and virtually in 13 states to provide personalized stroke care. 

Keep reading to learn more about dehydration, stroke, and the link between these two dangerous conditions.   

Understanding dehydration

To carry out and maintain your normal functions, your body relies on water. If you use or lose more fluids than you take in, your body enters a state called dehydration.  

Although people of all ages are susceptible to dehydration, it’s especially dangerous for very young children and older adults. Older adults in the winter are at risk because they naturally have less water in their bodies than younger people and the less humid winter air dries out your body. 

Many people believe feeling thirsty is the first sign of dehydration. Yet while thirst is a sign of this condition, you don’t experience thirst until you’re already in a state of dehydration. Other signs of dehydration include:

• Lack of need to urinate
• Dry mouth
• Muscle cramps
• Feeling dizzy or fainting
• Fatigue or lack of energy
• Dark, concentrated urine
• Rapid breathing and/or heartbeat
• Headache
• Confusion

Keep in mind that the signs of dehydration can vary depending on your age. For example, young children and infants may not have tears when they cry or seem especially lethargic. Older adults may have very dry skin, no sweat, or low blood pressure.  

If you’re only mildly dehydrated, you can restore hydration by drinking more fluids. If dehydration becomes severe, however, you need to seek immediate medical attention to prevent serious complications, like hypovolemic shock or seizure. 

Understanding stroke

You have a stroke, which is also referred to as a cerebrovascular accident (CVA), when the blood flow to your brain is blocked. When this happens, your brain can’t get the oxygen and nutrients it needs, and your brain cells begin to die. 

Anyone can have a stroke, but certain factors increase your risk, including hypertension, diabetes, carotid artery disease, heart disease, chronic inflammation, smoking, older age, family history, high cholesterol, and unmanaged chronic stress. 

There are different types of strokes. The most common is called an ischemic stroke. This happens when blood flow is blocked because of a build up of plaque or a blood clot in an artery. 

The less common hemorrhagic stroke happens when a blood vessel ruptures and you have bleeding in the brain. Both types of stroke cause similar symptoms, which include:

• Sudden onset of confusion or issues concentrating
• Sudden onset of slurred speech or inability to speak clearly
• Feeling dizzy or having a headache
• Sudden decrease in coordination or ability to move 
• Sudden weakness or clumsiness of a limb on one side of your body
• Sudden paralysis of a limb on one side of your body
• Sudden numbness in a limb or in the face
• Temporary blurred vision or loss of vision 

Because CVAs cause your brain cells to die, you have permanent brain damage after a stroke, although it’s possible to regain function. 

Other conditions may resemble a stroke but don’t have lasting effects. These include transient ischemic attacks (TIAs), sometimes called “mini-strokes,” and transient global amnesia (TGA). 

How dehydration and stroke are connected

When you’re dehydrated, your blood thickens. This makes blood flow throughout the body more challenging. If there is a narrow or blocked area in your blood vessels and you’re dehydrated, this double problem increases your risk of stroke. 

Research shows that nearly half of stroke patients are dehydrated at the time of first treatment, and up to two-thirds experience worsening dehydration during the time they’re at the hospital. This is important since dehydration negatively affects your ability to recover after a stroke. 

To help prevent a stroke and ensure your recovery after a CVA or similar incident, be sure to start your morning with a full cup of water and stay hydrated throughout the day by drinking one cup of water or other hydrating fluids for every 20 pounds you weigh (about 11.5 cups for women and 15.5 cups for men).  

Recovering from a stroke

If you’ve had a stroke or similar condition, it’s important to seek emergency help. After you’re released from the hospital, a board-certified neurologist can help you recover better with personalized stroke treatment. 

To learn more about dehydration and stroke or for ongoing stroke recovery assistance, schedule an in-person or virtual appointment with Dr. Ravitz at Modern Migraine MD.