The main causes of UK heatwave deaths

2022 and 2023 were the two hottest years on record in the UK, with June and September in 2023 being the hottest and joint hottest ever, respectively. Hot weather puts thousands of vulnerable people, including the elderly, at risk of heat-related deaths. Analysis by TakingCare Personal Alarms explores how many heat-related deaths occurred during this period, how this compares to previous years and offers predictions on how the number of heat-related deaths will increase as a result of climate change. With UK summers getting hotter every year, who is most at risk of heat-related deaths and what other factors are at play?

Contents:

• What is heat-related illness?
• UK heatwave deaths data
• DATA: elderly most at risk of heat-related deaths
• Rise in heat-related deaths linked to climate change
• Heatwave and COVID-19: summer 2020 had more deaths than the pan-European heatwave in 2003
• UK Heatwave 2022: England recorded 2,800 excess deaths in over 65s
• Summer 2023: More than 2,100 excess deaths in England in over 65s
• Data reveals the 5 main causes of death in a heatwave - and asthma sufferers are MOST at risk!
• Adults with dementia are more at risk of death during a heatwave
• The medication that can increase heat stress
• 5 hot weather tips that could save an older adult’s life

What is heat-related illness?

Heat-related illnesses are often grouped together as hyperthermia, which refers to a condition where your body is unable to maintain temperature and handle heat. Anyone can get a heat-related illness, but the risk is higher for elderly adults, overweight people, babies, young children, and people who have a pre-existing medical condition, such as heart disease.

Extreme temperatures kill 5 million people a year with heat-related deaths rising. The UK has a temperate climate, but England and Wales have seen some of the hottest summers in recent years with average temperatures rising over time.

Cold weather has previously been linked to deaths especially within the elderly demographic, but ONS has found a reduction in deaths caused by cold winters, flagging hot weather as the main risk.  

According to recent ONS government statistics, 1,272 people die every year on average from extreme weather, with 12,086 extra hospitalisations associated with hot days. 

When the UK’s hottest days are recorded, an increase in deaths follow. This report takes a look at the trends and reveals who is most at risk.

UK heatwave deaths data

TakingCare Personal Alarms conducted an analysis of the last seven years of Government data and found that, in total, 12,003 people in England have died from heat-related causes during summer periods classed as heatwaves.

2022 saw the highest number of recorded heatwave deaths over the last seven years in England, at 2,985, which followed the second highest in 2020, at 2,556 heatwave deaths, and 2023, which saw 2,295 deaths attributed to heatwaves during the English summer.

Across just the two hottest days of 2022 alone (July 19-20^th), ONS figures show that 1,134 more people died than would normally be expected.

According to ONS, rising temperatures could see heat-related deaths treble by 2050, with vulnerable people such as elderly adults most at risk.

According to ONS, rising temperatures could see heat-related deaths treble by 2050, with vulnerable people such as elderly adults most at risk.

Elderly most at risk of heat-related deaths

According to the most recent ONS data, 2117 over 65s died in England during the five warmest periods during summer 2023, which is 92% of all deaths that summer that were believed to be heatwave-related.

In fact, since the start of summer 2020, there have been 8670 heatwave deaths in over 65s, which is 92% of all heatwave deaths across all age groups during those four summers.

This shows the significant negative impact that heatwaves can have on the elderly.

Heat-related health dangers for older adults soar during summer and across the world, with a 54% increase in heated-related deaths in elderly people globally in the last two decades.

Over 65s are more at risk, especially if they have chronic conditions or problems getting around. Dehydration can be an issue, so can overheating, heat exhaustion and heatstroke. This data, and the increasing number of expected heat-related deaths in the future, indicates that more can be done to help protect the elderly and vulnerable during increasingly more frequent heatwaves.

Rise in heat-related deaths in the UK linked to climate change

Globally, human-induced climate change has been estimated to account for 37% of heat-related deaths.

Estimates suggest there will be a 257% increase in heat-related deaths and a 2% decline of cold weather deaths by 2050.

The global rise in temperature is putting us all at risk, regardless of who we are or where we live, with current environmental factors causing deeper strain for people suffering pre-existing health conditions, such as asthma. With a combination of factors that are affected by rising temperatures, heatwave deaths in the UK look set to continue to rise.

Heat makes air pollution worse - impacting the lungs. Ground-level ozone pollution, often called smog, is a common threat that’s exasperated during the summer months. Heat causes the ozone gases to react and aggressively attack lung tissue.

According to The World Health Organisation, a third of deaths from stroke, lung cancer and heart disease can all be linked back to air pollution.

Heatwave and COVID-19: Summer 2020 had more deaths than the pan-European heatwave in 2003

Summer 2020 had a high number of heatwave deaths, with 2,556 in total. This figure is comparable to the pan-European heatwave experienced in 2003, where 2,234 people sadly died due to sweltering temperatures of 38.5 degrees. Concerns were raised around global warming and the impact this has on heat-related deaths, as this was the hottest summer in Europe since 1540.

Why were heatwave related deaths so high during the pandemic?

The summer of 2020 was a time when many people in the UK were at their most isolated, and spending time in the garden or outdoors was an escape from the restrictions still in force across much of the country. It’s possible that the distraction of a global pandemic meant some people paid less attention to the basics of staying safe in hot weather.

UK Heatwave 2022: England recorded 2,800 excess deaths in over 65s

During the summer of 2022, the UK experienced one of the hottest summers in history, with reports indicating it was the joint hottest summer on record. According to provisional figures by the Met Office, the UK experienced an average temperature of 17.1°C during June, July and August, and record-breaking temperatures of over 40°C reported for the first time in July. This was comparable with the summer of 2018.

Between June 2022 and August 2022, the UK experienced five heat periods which can be defined as: day(s) on which a Level 3 Heat Health Alert is issued and/or day(s) when the mean Central England Temperature is greater than 20°C.

During the five heat-periods between June and August 2022, 56,303 deaths occurred in England and Wales and were registered by 7 September; this is 3,271 heatwave related deaths (6.2%) above the five-year average. The average number of deaths per day was also higher for heat-period days than non-heat-period days.

TakingCare Personal Alarms has analysed how the heatwave impacted the elderly. ONS data indicates that there were 5,017 deaths above average in those aged 70 years and over, compared with 1,749 deaths below average in those aged under 70 years. Across all five heat-periods of 2022, adjusting for registration delays, the estimated total excess mortality (excluding coronavirus (COVID-19)) in England was 2,803 for the most vulnerable age group (those aged 65 years and over), the highest number since the introduction of the Heatwave plan for England in 2004.

During the peak of the second heat-period, 17 to 20 July, the estimated total excess mortality (excluding COVID-19) was 1,012 excess deaths over a period of 4 days (253 excess deaths per day) for those aged 65 years and over.

The heat-period with the highest excess mortality (excluding COVID-19) in those 65 years and over was the fourth heat-period, 8 to 17 August, with 1,458 excess deaths over a period of 10 days (146 excess deaths per day).

This means that across these events, more than 2,800 excess deaths of over 65s during the heatwaves in the UK in 2022 were recorded.

Summer 2023: More than 2,100 excess deaths in England in over 65s

There were five ‘heat episodes’ recorded in the summer of 2023, during which there were 2,295 deaths associated with the hot weather, 2117 of which were people over the age of 65.

The longest period of sustained heat, which was recorded over 11 days between 3rd - 13th September 2023, saw yellow and amber warnings issued in various parts of England, and an average of 73 people, aged 65 and over, died from heat-associated reasons every day during that episode. The data shows that 801 people over 65 died during this single period of the summer due to the high temperatures.

Data reveals the 5 main causes of death in a heatwave - and asthma sufferers are MOST at risk!

We analysed ONS data from 2001-2020 looking at the top causes of death by temperature, revealing that the main causes are respiratory and cardiovascular.

Heatwaves cause premature deaths from cardiac, kidney and respiratory disease and according to the Environmental Audit Committee, there will be 7,000 heat-related deaths every year by 2050 if the Government doesn’t take action.

Breathing in hot or humid air can exacerbate respiratory conditions such as asthma, and analysing data shows over 30,674 respiratory deaths in warm weather across a 19-year period, averaging over 1,614 deaths each year.

Around 5.4 million people in the UK suffer from asthma and high temperatures mixed with increased pollen levels can be deadly. The data shows that 43.8% of deaths recorded during a heatwave are respiratory, showing how great the risk is for asthma sufferers.

Heatstroke is a danger but cardiovascular stress during a heatwave is deadly

The data reveals cardiovascular disease is one of the biggest causes of death during a heatwave, accounting for 43.7% of all deaths. Breaking down the data, 24,342 people died during a heatwave due to cardiovascular issues, averaging 1,281 every year.

What is cardiovascular disease (CVD)?

This is a general term which refers to conditions affecting the heart and blood vessels. CVD includes all heart circulatory diseases such as angina, heart attack, coronary heart disease, hypertension, stroke and vascular dementia.

When core body temperatures rise, thermosensors respond by shunting a large proportion of blood to the surface, this is to aid heat transfer from the body to the environment and allow for an increased sweat rate.

It’s this process of increased blood flow to the skin during soaring temperatures that puts the cardiovascular system at risk - the blood vessels near the skin need to dilate, forcing the heart to pump harder and faster.

Those who struggle to escape the heat are most at risk - advanced ageing and cardiovascular disease is the biggest factor. Elderly people have a reduced capacity to regulate their body temperatures or ‘thermoregulate’.

Interestingly, the elderly are not as adept at behavioural thermoregulation - which includes actions to protect yourself from soaring temperatures, such as seeking shade or air conditioned environments. These ‘cooling strategies’ are sought out less often than those of younger generations, which could be a contributing factor to deaths from heatwaves in the UK and globally.

According to new research, hotter nights increase the risk of death of heart disease from men in their early 60s. A rise of just 1°C above usual summer night-time temperatures could be linked to an increase in the risk of deaths from cardiovascular disease (CVD) in men in this age group.

Adults with dementia are more at risk of death during a heatwave

Breaking down the government data, those diagnosed with dementia were the fourth largest group who died during recorded heatwaves, with 7,045 deaths. This makes an average of 370 deaths from dementia-related heat illness every year.

Currently, there are over 850,000 people in the UK who are diagnosed with dementia. The most common form of dementia is Alzheimer's and it's estimated that 80% of all dementia illnesses are Alzheimer's related.

Take a look at our checklist for some of the early signs of dementia.

Why are Dementia sufferers more at risk?

Dehydration is a common challenge for older people, but elderly adults with dementia often forget to drink and need extra support keeping their fluid levels up when temperatures soar.

Studies have shown that in dementia sufferers, the part of your brain that recognises you’re dehydrated and sends a message to say you’re thirsty doesn’t always work. Also, some dementia medications can worsen dehydration as a side effect.

It’s a sad fact that dementia and falls go hand in hand - shockingly one in three adults over the age of 65 will have a fall this year, with dementia sufferers being more at risk. If a vulnerable adult with Alzheimer's has a fall outside during a heatwave, the effects could be devastating.

Research has shown that having a personal alarm reduces overall hospital admissions in older adults by 50% and by 44% where admissions were due specifically to falls. At TakingCare, some of our personal alarms have elderly fall alerts and other include GPS tracking like our personal alarm watch, which is particularly useful for family members and carers of elderly people with dementia, whether during a heatwave or all-year-round.

The medication that can increase heat stress

Shockingly, some medications can increase the risk of heat stress. How this works varies by medication but individuals taking the following medication should take extra care during a heatwave.

The below is an example of medication that can increase the risk of heat-related illness, but individual medications should be discussed with your doctor.

• Antidepressants, antihistamines, phenothiazines and anticholinergics (used for some psychiatric conditions) act on an area of the brain that controls the skin’s ability to make sweat.
• Beta blockers (heart tablets) reduce the ability of the heart and lungs to adapt to stresses including hot weather.
• Amphetamines raise body temperature.
• Diuretics (fluid tablets) act on the kidneys and encourage fluid loss. This can quickly lead to dehydration in hot weather.
• Opioids and sedatives can reduce the person’s awareness of physical discomfort, which means symptoms of heat stress may be ignored.

5 hot weather tips that could save an older adult’s life

As data about the UK heatwave deaths show, elderly adults are some of the most at risk of death during a heatwave. To help combat this, we’ve put together our key tips that will help keep them safe.

1. Keep hydrated

Elderly adults are more at risk of dehydration and overheating when it’s hot outside. Waiting until they feel thirsty could be dangerous, and having a continuous flow of liquids throughout the day is the safest option - the NHS say you should be aiming for around 1.2 litres, or, 6-8 glasses of water per day when temperatures soar, although some elderly adults may need more than this, depending on existing health conditions.

Eating foods with lots of natural liquids such as watermelon, strawberries, skimmed milk, cucumber and lettuce could help massively decrease dehydration. Ensure elderly adults are also eating a balanced diet to help their bodies replace any salt lost by sweating.

Your caffeine and alcohol intake should be limited during hot weather as they are both diuretics and advance dehydration in the body.

The elderly, babies and children are more at risk of dehydration - this means your body is losing more liquids than it can take in. If it’s not treated, it can become worse and cause serious problems. The NHS lists the following symptoms for dehydration:

• Feeling thirsty
• Dark yellow and strong-smelling urine
• Feeling dizzy or lightheaded
• Feeling tired
• A dry mouth, lips and eyes
• Needing to urinate little and fewer than 4 times a day

2. Avoid direct sun

Elderly adults should be encouraged to stay indoors when the sun is at its hottest, between the hours of 11am and 4pm. If this isn’t possible, it’s important to stay in areas of shade and out of direct sunlight. Always wear a hat whenever outdoors and remember to take extra precautions if spending time in the garden.

When it’s really hot, staying indoors is often best. Work out which is the coolest room in the house. Keep the curtains closed and use light-coloured fabrics if you can (because dark curtains can make a room hotter).

Remember that elderly people might not be able to tell when they’re feeling overheated or ill, so loved ones keeping an extra eye out for the signs and symptoms of heat-related illness is key during hot weather.

Older people have a tough time dealing with heat and humidity, and sometimes they might not know if they’re experiencing symptoms of a heat related illness. However, there are things you can look out for when caring for an elderly person:

• Dizziness or confusion
• Fast breathing or fast pulse
• A high temperature of 38 or above
• Excessive sweating and pale, clammy skin
• Loss of appetite and or feeling sick
• A headache
• Heat cramps: muscle spasms in the stomach, arms or legs
• Being very thirsty

3. Don’t use a stove or oven to cook

If you’re staying indoors, you should avoid making your home any hotter by using the oven or stove tops.

Any added heat could increase the risk of getting a heat-related illness, especially if you’re vulnerable. Slow cookers or air fryers are a great way to cook food without breaking a sweat -  the same goes for instant pots or multi cookers. Avoid dining al-fresco during the hottest hours of the day. Real Homes have put together some great recipe ideas to help avoid unnecessary heat in your kitchen.

4. Avoid synthetic fabrics

Suggesting a summer wardrobe shopping trip could be a good excuse to get an elderly person out of the house (and hopefully into an air-conditioned shopping centre) during a heatwave. Find clothes suitable for warmer weather and buy loose fitting clothing in pale shades. Avoid any heavy synthetic fabrics and opt for lightweight cottons to help keep them cool.

Older eyes can also have difficulty adjusting quickly to any changes in light to dark, so 100% UV protection sunglasses are a must. If elderly people’s eyes are exposed to bright sunlight throughout the day, it could lead to trips or falls when out and about. It’s a disturbing fact that there are nearly a quarter of a million falls-related emergency hospital admissions in England every year among patients aged 65 and over.

You can download our free guide to learn how to reduce the risk of a fall.

5. Keeping heat down at home

Not everyone has access to air conditioning, especially in the domestic setting. In order to keep temperatures down, you need to go against the grain and keep all windows closed during the day, keep curtains drawn or blinds pulled down to minimise rising temperatures through the glass. Once temperatures have cooled sufficiently in the evening, windows, blinds and curtains can then be reopened.

More information about staying safe in hot weather

For more tips on staying  safe during the UK’s heatwaves, we've put together 6 top tips in staying safe and enjoying the summer weather.