Hydration: A Simple Stroke Prevention Strategy?

Stroke is the fifth leading cause of death in America and the number one cause of long-term disability. Dehydration is a common issue for hospitalised stroke patients, with almost half of stroke patients admitted to hospital arriving dehydrated. Dehydration causes blood to thicken, making it more difficult for blood to flow to the brain. This can lead to a stroke if certain areas of the brain don't receive enough blood flow. Research has shown that stroke patients who are well-hydrated have better outcomes and are more likely to recover than those who are dehydrated. Therefore, staying hydrated may help prevent strokes and improve recovery. However, it is important to note that overhydration can also be dangerous, especially for people with heart and kidney conditions.

Dehydration and blood viscosity

Dehydration is a common condition that can have adverse effects on the body and brain. It can cause an array of symptoms, including excessive thirst, dry mouth, lethargy, muscle cramps, and dark-coloured urine. Dehydration can also impact the brain, leading to confusion, headache, lightheadedness, and even fainting.

One of the key mechanisms by which dehydration affects the body is by increasing blood viscosity. Blood viscosity refers to the thickness or fluidity of the blood. When the body is dehydrated, it doesn't have enough fluid to maintain adequate blood volume. This can lead to a decrease in blood pressure as the heart has less total blood to pump.

Several studies have shown the link between dehydration and increased blood viscosity. A study published in the journal Aviation, Space, and Environmental Medicine found that dehydration increased systolic blood viscosity by 9.3% and diastolic blood viscosity by 12.5%. Another study on the effects of dehydration in healthy adults also concluded that dehydration induced higher blood viscosity.

The implications of increased blood viscosity can be serious. High blood viscosity can cause infarction and other cardiovascular events. It can also increase the risk of developing deep vein thrombosis and pulmonary embolism.

To maintain healthy blood viscosity and prevent dehydration, it is important to stay adequately hydrated. This can be achieved by consuming adequate water or electrolyte-containing beverages, especially in hot or dry conditions.

The importance of hydration for stroke recovery

Hydration is essential for stroke recovery. Research shows that dehydrated stroke patients tend to have worse outcomes than those who are hydrated. In fact, dehydration is a common issue for hospitalised stroke patients, with over half becoming dehydrated during their stay. This is partly due to the physical and psychological difficulties that can affect a patient's ability to drink independently after a stroke.

Dehydration can cause the blood to thicken, making it more difficult for blood to flow to the brain. This can be particularly dangerous for stroke patients, as a stroke occurs when the blood flow to the brain is blocked or ruptured. Therefore, staying hydrated can help prevent further strokes and lead to better recovery outcomes.

It is recommended to drink a minimum of one cup of water for every 20 pounds of body weight to stay hydrated. This is especially important for those who have had a stroke or are at risk of having one. However, it is also important to note that overhydrating can also be dangerous, especially for those with heart and kidney conditions.

For stroke patients, proper hydration can be a challenge due to difficulties with swallowing or maintaining head control. Assistance from healthcare professionals may be required to ensure adequate fluid intake. Additionally, hydration status should be monitored regularly to prevent dehydration and maintain optimal recovery.

Overall, hydration plays a crucial role in stroke recovery. By staying hydrated, stroke patients can reduce their risk of further complications and improve their chances of a successful recovery.

The link between dehydration and blood pressure

Dehydration is a common issue for people who have had a stroke, with almost half of stroke patients admitted to hospital found to be dehydrated. Dehydration can cause blood to thicken, which in turn can lead to an increase in blood pressure. This is because thicker blood causes the body to retain sodium. Dehydration also causes a decrease in blood volume, which leads to a decline in blood pressure as the heart has less blood to pump.

It's important to note that overhydrating can also be dangerous, especially for people with heart and kidney conditions. Therefore, it's crucial to maintain proper hydration by drinking enough water regularly and paying attention to the body's thirst cues.

In summary, dehydration can lead to increased blood pressure by causing thicker blood and decreased blood volume. This link is significant for people who are at risk of or have had a stroke, as high blood pressure is a major risk factor for strokes. Maintaining proper hydration is essential to reduce the risk of dehydration-related complications.

How to identify dehydration

Dehydration is a serious condition that can lead to health complications, especially in children and older adults. It occurs when the body loses more fluids than it takes in, resulting in an electrolyte imbalance. Here are some detailed ways to identify dehydration:

• Urination and Urine Colour: One of the most common signs of dehydration is a decrease in urination or dark-coloured urine. Normal urine should be a pale yellow colour, similar to lightly coloured lemonade. If your urine resembles the colour of apple juice, it could indicate moderate to severe dehydration. Not urinating or experiencing a reduced urge to go to the bathroom could be a sign of severe dehydration, requiring immediate medical attention.
• Skin Elasticity: Lack of skin elasticity is another indicator of dehydration. You can perform a simple test by pinching the skin on the top of your hand and observing its movement. If the skin returns to its original position slowly, it suggests moderate dehydration. If the skin "tents" or sticks together, it indicates severe dehydration.
• Rapid Heartbeat and Breathing: While an increased heart rate and rapid breathing are typical during exercise, if these symptoms persist after cooling down or occur without physical activity, it could signify severe dehydration. This is because depleted blood volume can impair the heart's ability to pump blood effectively.
• Dizziness and Lightheadedness: Dehydration can negatively impact brain function, leading to dizziness, lightheadedness, or even fainting spells. This is due to the high water content of the brain, which is approximately 75%. Proper rehydration is crucial to alleviate these symptoms.
• Fatigue: Dehydration can affect your energy levels, making you feel more tired than usual. Studies have linked dehydration with shorter sleep duration and increased fatigue during exercise.
• Headaches: Dehydration is commonly associated with headaches. Reduced blood volume and insufficient oxygen reaching the brain due to dehydration can lead to narrowed blood vessels, affecting circulation and increasing the likelihood of headaches. Electrolyte imbalances caused by dehydration can also contribute to headache symptoms.
• Dry Mouth and Tongue: Dehydration can lead to a dry mouth and tongue, particularly in babies and young children. This is one of the early signs of dehydration in infants, along with a reduced number of wet diapers.
• Sunken Eyes: Dehydration can cause sunken eyes due to reduced fluid levels in the body. Additionally, individuals may experience dry eyes, a burning sensation, or a feeling of having sand in their eyes.

It is important to monitor dehydration symptoms and seek medical attention if necessary. Proper hydration is crucial for maintaining overall health and preventing severe health complications.

The role of dietitians in stroke patient care

Overview

Stroke patient care involves a multidisciplinary team, including dietitians, who play a crucial role in supporting patients' dietary intake, optimising nutritional intake, and improving recovery post-stroke. Adequate hydration is also a key factor in stroke prevention and recovery, and dietitians can help patients implement hydration strategies.

Dietary Challenges After a Stroke

Following a stroke, individuals may experience a range of challenges that impact their ability to eat and drink, such as problems with memory, loss of appetite, and swallowing difficulties (dysphagia). These issues can make it difficult for stroke survivors to obtain all the necessary nutrients for their recovery. Dietitians can provide specialist nutritional care to help manage these challenges.

Nutritional Care Plans

Dietitians work with stroke patients and their families to develop individualised nutritional care plans. These plans may include dietary texture modification for those with swallowing difficulties, tube feeding for those with unsafe swallowing, and addressing poor appetite, weight loss, and inadequate dietary intake.

Hydration Strategies

Hydration is an important aspect of stroke management and prevention. Dehydration can lead to imbalances in the body and brain, affecting blood volume and blood pressure, and ultimately leading to a stroke. Dietitians can educate patients on the importance of hydration and provide guidance on fluid intake, including recommending a minimum fluid intake of 2000 ml per day.

Healthy Eating Guidelines

Dietitians can also advise stroke patients on healthy eating habits to support their overall health and reduce the risk of a subsequent stroke. This includes recommending a balanced diet with plenty of fruits, vegetables, whole grains, lean proteins, and dairy or dairy alternatives, while limiting the intake of saturated fat, added salt, and added sugars.

Frequently asked questions