Dehydration is a common occurrence in the elderly. If it’s not monitored and resolved quickly, it can lead to serious and even fatal consequences. Understanding the causes and risk factors of dehydration — along with its physical and cognitive signs and symptoms — will enable you to respond quickly when caring for your aging loved ones.
What Is Dehydration, and Why Is It Important?
Dehydration is defined as the lack of water intake. The body naturally loses water daily through daily functions like sweating, elimination and evaporation. Dehydration happens when it’s not sufficiently replenished.
Water makes up about 50%-70% of your total body weight. Without enough water, human beings cannot survive. That’s because water contributes to a range of crucial functions:
- It helps the body’s cells, tissues and organs work properly.
- It rids the body of wastes (through urination, perspiration and bowel movements).
- It regulates the body’s temperature.
- It acts as a lubricant and cushion for joints.
- It protects sensitive tissues.
- It helps pump blood to the heart.
Being hydrated means your body has enough fluids to function properly. The specific amount of water each person needs can vary, according to the American Heart Association. They advise checking the color of your urine to tell whether you’re drinking enough water:
- A pale or clear color means you are likely well-hydrated.
- Dark-colored, amber or brown-colored urine means you may be dehydrated.
Signs and Symptoms of Dehydration in the Elderly
Each person experiences different symptoms when the body is distressed. But dehydration can affect older adults in different ways physically, mentally and emotionally because blood vessels in the brain and throughout the body constrict when fluid levels drop. As a result, dehydration signs may include:
- Fatigue and weakness
- Dizziness or loss of coordination
- Dry mouth or a dry cough
- Headaches
- Muscle cramps (due to electrolyte loss through sweating)
- Chills or heat intolerance
- Visibly flushed skin
The Prevalence of Dehydration in the Elderly
Research suggests that older adults are more at risk of becoming dehydrated than younger people for a variety of reasons. The National Council on Aging cites a study by the Los Angeles School of Nursing at the University of California, which found that up to 40% of the elderly lack adequate hydration and are considered chronically under hydrated.
The National Institutes of Health, Healthline and other sources indicate dehydration is one of the top common causes of hospital admissions and that people ages 65 and older are particularly susceptible. It is also associated with adverse health outcomes in hospital settings, including length of hospital stay, need for readmission, intensive care, poor prognosis and even death.
Risk Factors That Contribute to Dehydration in the Elderly
Certain qualities of a senior lifestyle along with simply aging can mean that certain elderly people are at a higher risk for dehydration. Here are some characteristics that caregivers, relatives and friends can look for in older people to be extra vigilant against dehydration:
- Less Thirst and Impaired Thirst Response: Older adults are more susceptible to becoming dehydrated than younger adults due to a diminished sense of thirst that can come with age.
- Physiological Changes with Age: Body composition changes, including a decline in the total amount of fluid in the body, naturally occur as people age. Older bodies often have fewer stored-up water reserves and need to be replenished more often.
- Aging of the Kidneys: The primary role of the kidneys is to remove waste from blood and produce urine. At birth, people have around a million nephrons that do this filtering job, but aging bodies naturally lose some, and some simply become less efficient. Proper hydration helps the whole kidney delivery system work better.
- Limited Mobility: Dehydration in older adults can be exacerbated if getting up and getting fluids regularly is physically challenging. Someone who struggles to walk across the room isn’t going to be refilling a cup at the water tap eight times a day.
- Psychological and Memory Issues: Older people may also fear incontinence while sleeping and therefore intentionally drink less during the day to try to keep it from happening. (Overnight incontinence in the elderly usually has a medical cause, so rather than limiting fluid intake, it’s a better idea to visit a health care professional.) Another aspect to consider is that dehydration can be the result of simply forgetting to drink enough liquids.
- Certain Medications: Elderly people are more likely to be taking medications that increase the risk of dehydration. For example, diuretics (water pills) increase urinary frequency, causing older adults to lose more fluid than usual, according to the American Heart Association.
Another risk factor to consider with senior dehydration is low socio-economic status. National health experts point out that dehydration is less common when there’s free access to water. But for most Americans, including seniors aging at home, water service isn’t “free.” Even though water is often supplied a very low cost, seniors struggling to pay bills may avoid using tap water when it’s metered or let service lapse.
In some cases, the issue isn’t affordability but the quality of the water that comes from the tap. Seniors may not drink enough because of reports or perceptions that the water supply is contaminated or otherwise unfit to consume. If they are unable or unwilling to buy large quantities of bottled drinking water, adequate hydration can quickly become a problem.
Geographic location can also play a major role in the risk of dehydration, particularly when living in hot, humid environments. Consider that in July 2023, Arizona’s Maricopa County experienced a streak of daily temperatures over 90 degrees, eventually reaching a record-breaking 119 degrees. That year, 645 heat-related deaths occurred there, with 95% of indoor heat-related deaths involving people aged 50 or older.
Preventing and Managing Dehydration in the Elderly
As a general rule, you should calculate one-third of your body weight and aim to take in that number of ounces of fluids per day. Note that this isn’t how much water you should drink but how much liquid you should consume, whether it’s in the form of water-rich foods like melon or oranges, broth-based soups or beverages like juice, smoothies, milk or tea.The daily overall fluid intake recommendation for people ages 51 and older is 13 cups for men and nine cups for women. The amount may differ depending on the person’s size, metabolism, location, diet and other factors.
Other prevention and management measures include:
- Adequate dietary intake
- Environmental modifications
- Monitoring for signs of dehydration
- Seeking prompt medical attention when needed
Prevention Is Key in Avoiding Elder Dehydration
Drinking water may sound simple and seem like an intuitive solution to avoid dehydration. However, dehydration can occur inadvertently because of a decrease in thirst as people age. As a result, dehydration is one of the most prevalent issues hospitals encounter when admitting the elderly. Worst-case scenarios are found in areas with extreme heat conditions.
To prevent this common and sometimes dangerous issue, know the risk factors and the physical and cognitive signs and symptoms of dehydration to help your loved ones avoid serious and preventable complications.