Hyperthermia and Heat Stroke in the Elderly: Signs, First Aid and Prevention

Summer brings the joy of sunny days and outdoor walks, but for the elderly people in our care, it can also pose a real health risk. When temperatures exceed 30 degrees and humidity becomes oppressive, older people's bodies respond differently from those of younger adults – more slowly, with greater difficulty, and sometimes too slowly to prevent harm. In those moments, every minute counts.

You may have noticed that your mother or father says "I'm not hot" even in the middle of a scorching day, or that they refuse to drink water because they're "not thirsty." These seemingly harmless behaviours can quickly lead to dehydration, heat exhaustion, or even heatstroke – conditions that can be life-threatening. As a family member, knowing what to look for and how to respond can make the difference between a minor episode and a medical emergency.

In this guide, we'll explain why older people are so vulnerable to heat, how to recognise the warning signs, and what practical steps you can take to protect your loved ones during heatwaves.

Contents

1. Why older people are more vulnerable to extreme heat
2. How to tell the difference: dehydration, heat exhaustion, and heatstroke
3. What to do at home immediately and when to call 112
4. How to adapt your home during heatwaves
5. Higher-risk groups: medications and chronic conditions
6. Preventive measures for every summer day
7. Frequently asked questions

Why older people are more vulnerable to extreme heat

As we age, our bodies undergo physiological changes that affect their ability to cope with high temperatures. For older people, these changes mean that the body's natural cooling mechanisms – sweating and vasodilation – work less efficiently. The sweat glands produce less perspiration, and the sense of thirst diminishes considerably, meaning older people may not feel the need to drink water even when their body is desperately in need of hydration.

Furthermore, the capacity for thermoregulation – that is, maintaining a constant body temperature – declines. A young adult can quickly sense when they are too hot and adjust their behaviour accordingly (seeking shade, drinking water, removing a layer of clothing). In older people, this internal "alarm system" functions less effectively, and they may continue to sit in the sun or in an overheated room without realising the danger.

Factors that increase the risk

Age alone is not the only factor. Several conditions and circumstances can worsen vulnerability to heat:

• Chronic cardiovascular disease – a weakened heart can no longer pump blood efficiently to the skin for cooling
• Diabetes mellitus – affects blood vessel function and perspiration
• Kidney disease – compromises the body's fluid balance
• Obesity or being underweight – both extremes impair thermoregulation
• Limited mobility – inability to move independently to access water or air conditioning
• Social isolation – no one present to monitor and notice changes

How to tell the difference: dehydration, heat exhaustion, and heatstroke

One of the most important things you can do for an older person during a heatwave is to learn how to identify the progressive stages of heat-related illness. These conditions do not appear suddenly – there is a progression, and if you intervene in time, you can prevent the situation from worsening.

Mild dehydration – the first signs

Dehydration occurs when the body loses more fluids than it takes in. In older people, it sets in quickly and can go unnoticed:

• A feeling of thirst (although in many older people, the absence of thirst does not rule out dehydration)
• Dryness of the mouth and lips
• Dark-coloured urine, produced in small amounts
• Unusual fatigue, mild dizziness
• The skin loses elasticity – if you gently pinch the skin on the back of the hand, it remains raised for a few seconds

Heat exhaustion – the intermediate stage

When the body can no longer cool itself effectively, the symptoms of heat exhaustion appear. This is a serious condition requiring prompt intervention:

• Heavy sweating and cool, clammy skin
• Muscle weakness, cramps
• Rapid, weak pulse
• Nausea, sometimes vomiting
• Severe headache
• Mild confusion, irritability

Heatstroke – a medical emergency

Heatstroke is the most serious form of heat-related illness and constitutes a life-threatening emergency. Body temperature exceeds 40 degrees and the thermoregulatory mechanisms fail completely:

• Absence of sweating – the skin becomes hot, dry, and red
• Very high body temperature (above 40°C)
• Severe confusion, difficulty speaking
• Seizures, loss of consciousness
• Rapid, shallow breathing
• Very rapid, strong pulse

If you observe these symptoms, every second counts. Heatstroke can cause permanent brain damage or death if not treated immediately.

What to do at home immediately and when to call 112

When you suspect that an older member of your family is suffering from the effects of heat, your prompt response can save lives. Here is what to do depending on the severity of the situation.

For mild dehydration

1. Move the person to a cool place, in the shade or in an air-conditioned room
2. Offer them water at room temperature, in small, frequent sips (not cold water all at once!)
3. Dampen their face, neck, and wrists with cool water
4. Help them lie down with their legs slightly elevated
5. Monitor their condition over the following hours

For heat exhaustion

If the symptoms are more severe but the person is conscious:

1. Call 112 immediately and describe the symptoms clearly
2. While waiting for the ambulance, move the person to a cool place
3. Remove any excess clothing and loosen their belt and collar
4. Apply cool compresses (not ice!) to the forehead, back of the neck, armpits, and groin
5. If they can swallow, offer water or an electrolyte drink in small sips
6. Do not give aspirin or paracetamol – these will not help and may worsen the situation

For heatstroke – maximum emergency

Call 112 immediately and follow these vital steps until the ambulance arrives:

• Move the person to a shaded area or a cool room
• Remove as much clothing as possible
• Attempt to lower the body temperature rapidly: apply cool, wet towels over the body and fan them
• If they are conscious and able to swallow, offer a small amount of water
• If they are unconscious, place them in the recovery position
• Do not give drinks containing caffeine or alcohol
• Do not apply ice directly to the skin – this can cause thermal shock

How to adapt your home during heatwaves

Prevention begins at home. The home in which an older person lives can become either a safe refuge or a heat trap. With a few simple adjustments, you can transform the family environment into a protective space.

Managing indoor temperature

Even without air conditioning, there are effective cooling methods:

• Close the blinds and curtains during the day on windows that face the sun
• Ventilate the home early in the morning and late in the evening, when it is cooler
• Use fans, but do not point them directly at the older person
• Place bowls of cold water in front of the fan for evaporative cooling
• Avoid using the oven or heat-generating appliances during the hottest hours of the day

Ensuring consistent hydration

Because older people do not feel thirsty, hydration must be built into a routine:

• Leave glasses of fresh water in several places around the home (next to the armchair, on the bedside table, at the dining table)
• Set phone alarms as reminders to drink water every one to two hours
• Offer appealing alternatives: water with lemon, cold fruit teas, cold soup
• Keep water-rich fruits within easy reach: watermelon, strawberries, oranges
• Record the amount of fluid consumed each day for monitoring purposes

Clothing and daily routine

Adapt the daily schedule and wardrobe to heatwave conditions:

1. Encourage loose-fitting clothing made from cotton or linen in light colours
2. Adjust the routine: physically demanding activities should take place early in the morning or in the evening
3. Recommend frequent cool showers or baths (not suddenly cold ones!)
4. Keep damp towels in the refrigerator for quick cooling
5. Limit time outdoors between 11:00 and 17:00

Higher-risk groups: medications and chronic conditions

Certain medications and medical conditions significantly increase the risk of heat-related problems. It is essential to know whether your parent or grandparent falls into a higher-risk category, and to discuss additional protective measures with their GP.

Medications that affect thermoregulation

Many treatments commonly used by older people interfere with the body's ability to manage heat:

• Diuretics – used for blood pressure and heart failure, they increase the loss of fluids and minerals
• Beta-blockers – for the heart and blood pressure, they reduce the body's ability to respond to heat stress
• Anticholinergics – many medications for Parkinson's disease, depression, and incontinence inhibit sweating
• Antihypertensives – can affect circulation and cooling through vasodilation
• Antipsychotics and antidepressants – disrupt the central mechanism for temperature regulation
• Antihistamines – reduce sweating

Chronic conditions that increase vulnerability

Older people with certain health conditions require closer supervision during heatwaves:

• Cardiovascular disease – an overworked heart may not be able to cope with the additional strain
• Diabetes – affects sweating and the sensation of thirst
• Chronic lung disease – breathing difficulties worsened by heat
• Dementia or Alzheimer's disease – inability to recognise thirst or heat
• Obesity – excess body fat retains heat

What to discuss with the doctor

Before the warm season begins, schedule an appointment and ask:

1. Whether medication dosages need to be adjusted during heatwaves
2. How much water they should drink each day
3. Whether there are specific restrictions on physical activity in the heat
4. What the warning signs are specific to their condition
5. Whether they need electrolyte supplements

Important: Never stop or alter medication on your own initiative. Any adjustment must be made only under medical supervision.

Preventive measures for every summer day

Protecting against heat is not just about responding to emergencies – it is above all about consistent prevention. Establishing safe daily habits can almost entirely eliminate the risk of heat exhaustion or heatstroke.

Daily checklist

For families caring for an older person, here are the routines that should become second nature during the warmer months:

• Check the weather forecast and plan the day accordingly
• Ensure that a minimum of 6–8 glasses of water or fluids are consumed each day
• Monitor urine colour – if it is dark, increase fluid intake
• Check the room temperature – ideally between 20–24°C
• Check what they are wearing – light, breathable clothing
• Call or visit daily if they live independently
• Ask about their general wellbeing: headaches, dizziness, fatigue

Building a safety network

Isolation is one of the major risk factors. For older people living alone:

1. Establish a daily contact schedule (telephone call or visit)
2. Inform neighbours and ask them to keep an eye out
3. Leave emergency contact numbers in a visible place near the telephone
4. Consider a home care service during periods of extreme heat
5. Find out whether there are any air-conditioned day centres for older people where they can spend a few hours

The family emergency plan

Every family should have a clear plan for red-alert heatwave days:

• Identify the nearest medical centre or hospital
• Keep a working digital thermometer readily available
• Keep clean towels in the refrigerator for cool compresses
• Make sure you have the telephone numbers of the GP and neighbours to hand
• If you use professional care services, check their availability at weekends and on public holidays

Frequently asked questions

How much water should an older person drink during a heatwave?

The general recommendation is a minimum of 1.5–2 litres per day, but larger amounts may be necessary depending on the outdoor temperature, activity level, and medication. If the person takes diuretics or has kidney or heart problems, consult their doctor for personalised recommendations. A good indicator is urine colour – it should be pale yellow.

Is air conditioning dangerous for older people?

No, provided it is used correctly. The temperature should not be set too low (ideally 23–25°C), and the airflow should not be directed straight at the person. The difference between the indoor and outdoor temperature should not exceed 7–8 degrees, in order to avoid thermal shock. Cleaning the filters is essential for preventing respiratory problems.

Can I give soft drinks or juice instead of water?

Plain water remains the best option. Fruit juices contain sugar, which can cause dehydration, whilst carbonated drinks may cause bloating. Unsweetened teas, naturally fruit-flavoured water, or electrolyte drinks designed for older people are good alternatives. Avoid caffeine and alcohol – both are dehydrating.

What should I do if they refuse to drink water because they say they're not thirsty?

A diminished sense of thirst is common in older people and does not reflect the body's true hydration needs. Try making hydration more appealing: offer water-rich fruits (watermelon, grapes), cold soup, homemade ice lollies, or water flavoured with mint or lemon. Establish a fixed hydration schedule that does not depend on the sensation of thirst, and use small glasses to make the amounts easier to manage.

How do I know whether they are dehydrated or have another health problem?

Check for the specific signs of dehydration: dry mouth, dark and scant urine, skin that has lost its elasticity, and dizziness upon standing. If symptoms such as chest pain, severe confusion, loss of consciousness, or seizures occur, call 112 immediately – these may indicate serious cardiac or neurological problems, not merely dehydration.

Is it safe to go outside in the heat if they wear a hat?

A hat helps, but it is not sufficient for complete protection. Outings should be planned for early morning (before 10:00) or evening (after 18:00), along short routes, with frequent stops in the shade. Even wearing a hat, prolonged exposure to the sun between 11:00 and 17:00 remains dangerous. Always check the heat index, not just the temperature.

Extreme heat should not be regarded as a mere summer discomfort, but as a genuine health risk for the older people in your family. With vigilance, accurate information, and consistent preventive measures, you can ensure their comfort and safety even on the hottest days. If you have any doubts or notice worrying changes, do not hesitate to consult your GP or call the emergency services – it is always better to err on the side of caution.

This article is for informational purposes only and does not replace medical advice. For specific situations, please consult a healthcare professional.