Extreme heat is increasingly common in Australia and around the world and besides making us uncomfortable, it can harm our health. For example, exposure to extreme heat can exacerbate existing medical conditions, or cause problems such as heat stroke.

Due to a combination of physiology and behaviour, children are potentially more vulnerable to severe heat-related illness such as heat stroke or heat exhaustion.

But these are not the only heat-related health issues children might experience on a very hot day. In a new study, we looked at emergency department (ED) visits and unplanned hospital admissions among children in New South Wales on heatwave days.

We found a significant increase in children attending hospital compared to milder days – with a range of health issues.

Why are children more vulnerable in the heat?

Sweating is the main way we lose heat from our bodies and cool down.

Children have a greater skin surface area to body mass ratio, which can be an advantage for sweating – they can lose more heat through evaporation for a given body mass. But this also means children can lose fluids and electrolytes faster through sweating, theoretically making them more susceptible to dehydration.

Meanwhile, younger children, particularly babies, can’t sweat as much as older children and adults. This means they can’t cool down as effectively.

Children in general also tend to engage in more outdoor physical activity, which might see them more exposed to very hot temperatures.

Further, children may be less in-tune to the signals their body is giving them that they’re overheating, such as excessive sweating or red skin. So they might not stop and cool down when they need to. Young children especially may not recognise the early signs of heat stress or be able to express discomfort.

Our study

We wanted to examine children’s exposure to extreme heat stress and the associated risks to their health.

We measured extreme heat as “heatwave days”, at least two consecutive days with a daily maximum temperature above the 95th percentile for the relevant area on a universal thermal climate index. This ranged from 27°C to 45°C depending on the area.

We assessed health outcomes by looking at ED visits and unplanned hospital admissions among children aged 0–18 years from NSW between 2000 and 2020. This totalled around 8.2 million ED visits and 1.4 million hospital admissions.

We found hospital admissions for heat-related illness were 104% more likely on heatwave days compared to non-heatwave days, and ED visits were 78% more likely. Heat-related illness includes a spectrum of disorders from minor conditions such as dehydration to life-threatening conditions such as heat stroke.

But heat-related illness wasn’t the only condition that increased on heatwave days. There was also an increase in childhood infections, particularly infectious enteritis possibly related to food poisoning (up 6% for ED visits and 17% for hospital admissions), ear infections (up 30% for ED visits and 3% for hospital admissions), and skin and soft tissue infections (up 6% for ED visits and 4% for hospital admissions).

We know many infectious diseases are highly seasonal. Some, like the flu, peak in winter. But heat and humidity increase the risk of certain infections caused by bacterial, viral and fungal pathogens.

For example, warmer weather and higher humidity can increase the survival of bacteria, such as Salmonella, on foods, which increases the risk of food poisoning.

Hot weather can also increase the risk of ear infections. Children may be at greater risk during hot weather because they often swim or play at the beach or pool. Water can stay in the ear after swimming and a moist environment in the ear canal can cause growth of pathogens leading to ear infections.

Which children are most vulnerable?

During heatwaves, we found infants aged under one were at increased risk of ED visits and hospital admission for any reason compared to older children. This is not surprising, because babies can’t regulate their body temperature effectively and are reliant on their caregivers to keep them cool.

Our study also found children from the most disadvantaged areas were more vulnerable to heat-related illness on heatwave days. Although we don’t know exactly why, we hypothesised families from poorer areas might have limited access to air-conditioning and could be more likely to live in hotter neighbourhoods.

Keeping kids cool: tips for parents

The highest levels of heat exposure on hot days for young children is usually when they’re taken outside in prams and strollers. To protect their children from direct sunlight, parents often instinctively cover their stroller with a cloth such as a muslin.

However, a recent study from our group showed this actually increases temperatures inside a stroller to as much as 3–4˚C higher than outside.

But if the cloth is wet with water, and a small fan is used to circulate the air close to the child, stroller temperatures can be 4–5˚C lower than outside. Wetting the cloth every 15–20 minutes (for example, with a spray bottle) maintains the cooling effect.

When young children are not in a stroller, and for older children, there are a few things to consider to keep them cool and safe.

Remember temperatures reported on weather forecasts are measured in the shade, and temperatures in the sun can be up to 15˚C higher. So sticking to the shade as much as possible is important.

Exercise generates heat inside the body, so activities should be shortened, or rescheduled to cooler times of the day.

Sunscreen and hats are important when outdoors, but neither are especially effective for keeping cool. Spraying water on the child’s skin – not just the face but arms, legs and even the torso if possible – can help. Wetting their hats is another idea.

Proper hydration on hot days is also essential. Regular water breaks, including offering water before, during and after activity, is important. Offering foods with high water content such as watermelon and orange can help with hydration too.

Wen-Qiang He, Research Fellow in Biostatistics and Epidemiology, Faculty of Medicine and Health, University of Sydney; James Smallcombe, Post-doctoral Research Associate, Faculty of Medicine and Health, University of Sydney; Natasha Nassar, Professor of Paediatric and Perinatal Epidemiology and Chair in Translational Childhood Medicine, University of Sydney, and Ollie Jay, Professor of Heat & Health; Director of Heat & Health Research Incubator; Director of Thermal Ergonomics Laboratory, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

If you or a loved one have noticed changes in your memory or thinking as you’ve grown older, this could reflect typical changes that occur with ageing. In some cases though, it might suggest something more, such as the onset of dementia.

The best thing to do if you have concerns is to make an appointment with your GP, who will probably run some tests. Assessment is important because if there is something more going on, early diagnosis can enable prompt access to the right interventions, supports and care.

But current methods of dementia screening have limitations, and testing can be daunting for patients.

Our research suggests virtual reality (VR) could be a useful cognitive screening tool, and mitigate some of the challenges associated with current testing methods, opening up the possibility it may one day play a role in dementia diagnosis.

Where current testing is falling short

If someone is worried about their memory and thinking, their GP might ask them to complete a series of quick tasks that check things like the ability to follow simple instructions, basic arithmetic, memory and orientation.

These sorts of screening tools are really good at confirming cognitive problems that may already be very apparent. But commonly used screening tests are not always so good at detecting early and more subtle difficulties with memory and thinking, meaning such changes could be missed until they get worse.

A clinical neuropsychological assessment is better equipped to detect early changes. This involves a comprehensive review of a patient’s personal and medical history, and detailed assessment of cognitive functions, including attention, language, memory, executive functioning, mood factors and more. However, this can be costly and the testing can take several hours.

Testing is also somewhat removed from everyday experience, not directly tapping into activities of daily living.

Enter virtual reality

VR technology uses computer-generated environments to create immersive experiences that feel like real life. While VR is often used for entertainment, it has increasingly found applications in health care, including in rehabilitation and falls prevention.

Using VR for cognitive screening is still a new area. VR-based cognitive tests generally create a scenario such as shopping at a supermarket or driving around a city to ascertain how a person would perform in these situations.

Notably, they engage various senses and cognitive processes such as sight, sound and spatial awareness in immersive ways. All this may reveal subtle impairments which can be missed by standard methods.

VR assessments are also often more engaging and enjoyable, potentially reducing anxiety for those who may feel uneasy in traditional testing environments, and improving compliance compared to standard assessments.

Most studies of VR-based cognitive tests have explored their capacity to pick up impairments in spatial memory (the ability to remember where something is located and how to get there), and the results have been promising.

Given VR’s potential for assisting with diagnosis of cognitive impairment and dementia remains largely untapped, our team developed an online computerised game (referred to as semi-immersive VR) to see how well a person can remember, recall and complete everyday tasks. In our VR game, which lasts about 20 minutes, the user role plays a waiter in a cafe and receives a score on their performance.

To assess its potential, we enlisted more than 140 people to play the game and provide feedback. The results of this research are published across three recent papers.

Testing our VR tool

In our most recently published study, we wanted to verify the accuracy and sensitivity of our VR game to assess cognitive abilities.

We compared our test to an existing screening tool (called the TICS-M) in more than 130 adults. We found our VR task was able to capture meaningful aspects of cognitive function, including recalling food items and spatial memory.

We also found younger adults performed better in the game than older adults, which echoes the pattern commonly seen in regular memory tests.

In a separate study, we followed ten adults aged over 65 while they completed the game, and interviewed them afterwards. We wanted to understand how this group – who the tool would target – perceived the task.

These seniors told us they found the game user-friendly and believed it was a promising tool for screening memory. They described the game as engaging and immersive, expressing enthusiasm to continue playing. They didn’t find the task created anxiety.

For a third study, we spoke to seven health-care professionals about the tool. Overall they gave positive feedback, and noted its dynamic approach to age-old diagnostic challenges.

However, they did flag some concerns and potential barriers to implementing this sort of tool. These included resource constraints in clinical practice (such as time and space to carry out the assessment) and whether it would be accessible for people with limited technological skills. There was also some scepticism about whether the tool would be an accurate method to assist with dementia diagnosis.

While our initial research suggests this tool could be a promising way to assess cognitive performance, this is not the same as diagnosing dementia. To improve the test’s ability to accurately detect those who likely have dementia, we’ll need to make it more specific for that purpose, and carry out further research to validate its effectiveness.

We’ll be conducting more testing of the game soon. Anyone interested in giving it a go to help with our research can register on our team’s website.

Joyce Siette, Research Theme Fellow in Health and Wellbeing, Western Sydney University and Paul Strutt, Senior Lecturer in Psychology, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Summer is nearly here. But rather than getting out the sunscreen, some TikTokers are urging followers to chuck it out and go sunscreen-free.

They claim it’s healthier to forgo sunscreen to get the full benefits of sunshine.

Here’s the science really says.

How does sunscreen work?

Because of Australia’s extreme UV environment, most people with pale to olive skin or other risk factors for skin cancer need to protect themselves. Applying sunscreen is a key method of protecting areas not easily covered by clothes.

Sunscreen works by absorbing or scattering UV rays before they can enter your skin and damage DNA or supportive structures such as collagen.

When UV particles hit DNA, the excess energy can damage our DNA. This damage can be repaired, but if the cell divides before the mistake is fixed, it causes a mutation that can lead to skin cancers.

The most common skin cancers are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Melanoma is less common, but is the most likely to spread around the body; this process is called metastasis.

Two in three Australians will have at least one skin cancer in their lifetime, and they make up 80% of all cancers in Australia.

Around 99% of skin cancers in Australia are caused by excessive exposure to UV radiation.

Excessive exposure to UV radiation also affects the appearance of your skin. UVA rays are able to penetrate deep into the skin, where they break down supportive structures such as elastin and collagen.

This causes signs of premature ageing, such as deep wrinkling, brown or white blotches, and broken capillaries.

Sunscreen can help prevent skin cancers

Used consistently, sunscreen reduces your risk of skin cancer and slows skin ageing.

In a Queensland study, participants either used sunscreen daily for almost five years, or continued their usual use.

At the end of five years, the daily-use group had reduced their risk of squamous cell carcinoma by 40% compared to the other group.

Ten years later, the daily use group had reduced their risk of invasive melanoma by 73%

Does sunscreen block the health-promoting properties of sunlight?

The answer is a bit more complicated, and involves personalised risk versus benefit trade-offs.

First, the good news: there are many health benefits of spending time in the sun that don’t rely on exposure to UV radiation and aren’t affected by sunscreen use.

Sunscreen only filters UV rays, not visible light or infrared light (which we feel as heat). And importantly, some of the benefits of sunlight are obtained via the eyes.

Visible light improves mood and regulates circadian rhythm (which influences your sleep-wake cycle), and probably reduces myopia (short-sightedness) in children.

Infrared light is being investigated as a treatment for several skin, neurological, psychiatric and autoimmune disorders.

So what is the benefit of exposing skin to UV radiation?

Exposing the skin to the sun produces vitamin D, which is critical for healthy bones and muscles.

Vitamin D deficiency is surprisingly common among Australians, peaking in Victoria at 49% in winter and being lowest in Queensland at 6% in summer.

Luckily, people who are careful about sun protection can avoid vitamin D deficiency by taking a supplement.

Exposing the skin to UV radiation might have benefits independent of vitamin D production, but these are not proven. It might reduce the risk of autoimmune diseases such as multiple sclerosis or cause release of a chemical that could reduce blood pressure. However, there is not enough detail about these benefits to know whether sunscreen would be a problem.

What does this mean for you?

There are some benefits of exposing the skin to UV radiation that might be blunted by sunscreen. Whether it’s worth foregoing those benefits to avoid skin cancer depends on how susceptible you are to skin cancer.

If you have pale skin or other factors that increase you risk of skin cancer, you should aim to apply sunscreen daily on all days when the UV index is forecast to reach 3.

If you have darker skin that rarely or never burns, you can go without daily sunscreen – although you will still need protection during extended times outdoors.

For now, the balance of evidence suggests it’s better for people who are susceptible to skin cancer to continue with sun protection practices, with vitamin D supplementation if needed.

Katie Lee, PhD Candidate, Dermatology Research Centre, The University of Queensland and Rachel Neale, Principal research fellow, QIMR Berghofer Medical Research Institute

This article is republished from The Conversation under a Creative Commons license. Read the original article.