
How dehydration in seniors confuses the brain
I was about 70 when I learned first-hand how dehydration confuses the brain. I was still flying gliders then. It was a miserably hot and humid day. I hadn’t had a drink of water for hours. I had just taken off, with my wife in the front seat of the glider. The tow plane was hauling us towards 2000 feet above ground on the end of a long rope. I was having a hard time following the tow plane through the ups and downs of air currents.
I suddenly realized that my ability to sense what was happening, process it and respond smartly was so bad it frightened me. I was woozy. I released from the tow as soon as it was safe to and abandoned the sight-seeing flight I wanted to give my wife. I immediately returned to the airfield and landed.
Dehydration does that to your brain. And the risk of it happening is greater as we age. Researchers at the Howard Fiory Institute in Melbourne, Australia, discovered that a region in the brain called the mid-cingulate cortex predicts how much water a person needs, but this region malfunctions in older people. Fiory’s Dr. Michael Farrell said, “Using PET imaging, we found in the older people the mid-cingulate cortex was ‘turned off’ much earlier by drinking small volumes (of water),” according to a report in Science Daily. Here’s a summary of the original research
Dr. Carol Greenwood is Baycrest senior scientist and professor of nutritional sciences at the University of Toronto. She explains, “We know that as people become dehydrated their cognitive function decreases quite substantively – to the point that you may see mental confusion in some people. It’s very important that older adults ensure that they are drinking sufficient amounts of fluid.”
4 surprising hazards of dehydration
In Nursing magazine, Margaret Cramer’s blog described some of the dangers elderly people face if we let ourselves run dry. Frankly, some of them jolted me. Sure, I knew that some 60% of our total body weight is water. But I had never known how that relates to the dangers of dehydration. Just look:
- Decreased total blood volume resulting in…
- Increased heart rate
- But insufficient blood to the brain, liver and kidneys and…
- Possible organ failure (even, at the extreme, death).
Margaret Cramer’s blog
Dehydration may explain mysterious falls by elderly
Deborah Leader, RN, BSN, PH, reported in her blog that dehydrated elderly people often experience dizziness – especially when they stand suddenly. That dizziness often causes a fall. Her blog also cites the other common consequences of dehydration:
- Decreased urine output
- Dry skin
- Poor skin elasticity
- Constipation
- Fecal impaction.
The people at highest risk of dehydration
They include, according to Leader’s blog:
- Seniors who live alone
- People admitted to hospital
- Those recovering from major surgery
- Disabled people
- Arthritics
- Alzheimer’s patients
- Patients who live in nursing homes.
Deborah Leader’s blog
Four reasons why we elders have to drink more
According to Baycrest dietician Iris Weienberg:
- Our thirst receptors don’t give us the same clues to drink as we used to get.
- Some medications push water out of our body cells. Blood pressure drugs are among these diuretics. Your physician or pharmacist can tell you which of your medicines will dry you out.
- A special diet may restrict a person’s fluid intake.
- Some people are incontinent and self-restrict to control the need to go to the washroom.
Eight ways can you supply yourself with enough liquid
Baycrest recommends at least 1500 ml of liquid per day – about six cups. One easy way to guarantee you’re getting enough water is to fill a container that measures 1,500 ml with water, put it in the fridge in the morning and make you finish it by the end of the day. But water is just one way to get the liquid you need and also get some pleasure from having it. Here are seven other ways:
- Coffee
- Tea
- Soup
- Cooked cereals
- Yogurt
- Pudding
- Apple sauce
Watch for these warning signs of dehydration in yourself or a loved one
- Reduced urination or concentrated, very yellow urine
- Dry mouth
- Dry or sunken eyes
- Dizziness
- Rapid weight loss
- Increased confusion or changed mental state.
Never underestimate the relationship between hydration and health
Lisa Wiseman, a Registered Nurse and President of Eldercare Home Health, sees seniors in hospitals, nursing homes, retirement homes and their own homes. It is very common that the seniors she meets in every one of these environments are dehydrated.
Those who are aware, physically able and cognitively intact may be busy, not thirsty; just not thinking about hydrating. Others may purposely restrict fluids to reduce the need to make multiple trips to the bathroom….especially overnight.
Those who are not aware, are physically challenged or not cognitively intact may not recognize the sensation of thirst. They may lack the initiative to take care of themselves. The care provider’s attention may lapse. The patient may be depressed. Or a mobility restriction, whether in walking, balancing, reaching or carrying, may make it too difficult for the patient to go get a drink.
Dehydration itself perpetuates dehydration because it makes a person increasingly tired, confused and disoriented.
In her practice, Lisa has seen how restoring adequate hydration can reduce confusion, lift mood and improve initiative and the ability to communicate well with others. She has witnessed improvements to a person’s balance, the return of regular bowel function, a reduction in the number of medications needed and an overall improvement in quality of life.
According to “Boosting your Energy,” a Harvard Medical School Special Health Report, water is the only nutrient that will enhance performance for most activities. It carries nutrients to the cells and removes waste products.
Health care providers need to remember to consider hydration when assessing older people. Before they engage specialists, order invasive tests and prescribe pharmaceuticals, the starting point should always be a thorough physical assessment. Basic as it may sound, hydration status is an important and often overlooked factor affecting good health.
Stay hydrated, stay safe.
Dehydration is silent and dangerous. It sneaks up on you. I’ve experienced its effects. So now I make it a habit to have a drink of liquid here, a drink there, all through the day. After exercise, on a very hot day or if I’ve had a fever or upset stomach, I make sure to replenish the liquid I’ve lost with extra fluid. Please do the same for yourself or a loved one in your care.
Cubby Marcus (CM) is semi-retired communications professional, former glider pilot and a regular contributor to the Eldercare Home Health blog.
Thanks for covering this topic. I was surprised today to view a clip on ABC news that said thirst is an adequate reminder that we need hydration. This was such a disservice to the viewers. From Dr. Google to the first several articles on PubMed, all said that thirst is a poor indicator of the bodies need for water, especially in the elderly.