HOW CLIMATE CHANGE IS IMPACTING OUR HEALTH

How CLIMATE CHANGE is impacting our health Blue skies and sunshine lift our spirits, but now scientists are discovering new ways the changing weather is affecting our wellbeing. Tessa Hilton investigates

From headaches to heatstroke; how to protect yourself in our changing weather

Hay fever sufferers are used to checking the Met Office’s pollen forecast, but are we approaching a time when those with conditions such as arthritis, fibromyalgia and migraine will look ahead to see if incoming weather is likely to trigger pain flare-ups? As more is becoming known about how the weather influences our physical health, we can use this understanding to better manage our symptoms, says Professor Will Dixon, clinical rheumatologist at Salford Royal Hospital, who is leading research that may one day enable patients to access personalised pain forecasts.

We know that climate change is altering our weather, and researchers are now looking at the ways our wellbeing is affected. For instance, hay fever season now starts earlier, as rising temperatures bring trees out of hibernation sooner than normal. And more heat-related illnesses are occurring than in the past: there are already around 800 deaths and 80,000 extra days spent in hospital every year due to the mercury soaring.

Extremes of heat or cold can affect heart health, even in people with no preexisting conditions, and air pollution intensifies as the temperature rises, with serious implications for our lungs.

The good news, though, is that as science uncovers more about the impact the weather has on our health, it also reveals how to offset risks and sidestep triggers. ‘Almost every week, someone in my clinic will say their pain is better or worse because of the weather,’ says Professor Dixon, whose study, Cloudy With A Chance Of Pain, showed low atmospheric pressure and high humidity and wind speed increased the chance of pain by up to 20% in those with arthritis, fibromyalgia, migraine and neuropathic pain. More than 13,000 people across the UK took part in the research, by recording daily symptoms on a smartphone app, which also linked to their local weather station. ‘This research gave the medical community, which had often previously discounted weather as a possible trigger, scientifically robust evidence, and enabled patients to feel believed when they described symptoms correlating with low pressure or humidity,’ says Professor Dixon.

In parallel, Professor Dixon ran a second smartphone study with people living with rheumatoid arthritis – REMORA (remote monitoring of rheumatoid arthritis). This again tracked symptoms and weather data, but delivered the results in the form of a graph directly into their electronic medical records. Now he hopes to prove this is worth extending throughout the health service, as September sees the start of a large-scale study involving 500 patients and multiple different hospital clinics.

Meanwhile, questions about why and how the weather affects so many conditions still need to be answered. Scientists don’t yet fully understand the processes, says Professor Dixon, but he suggests, ‘In the case of inflammatory arthritis, where a build-up of fluid puts pressure on joints, a change in air pressure might lead to a change of symptoms. With osteoarthritis, bone cysts develop, and perhaps pressure influences that.’

Temperature is easier to understand, as ice packs and heat have long been proven as effective self-management options. But when it comes to humidity, science still lacks definitive answers.

To discover to what extent your own pain is weather-sensitive, Professor

Dixon suggests monitoring symptoms using a free app such as Manage My Pain, and adding weather information for your local area (metoffice.gov.uk). If you find there is a correlation, you can use this information to manage flare-ups by rescheduling demanding days, being extra-vigilant about medication and practising the best self-care.

METEOROLOGICAL MIGRAINES

A drop in air pressure ahead of bad weather also appears to be a common trigger for migraines, according to neurology and headache specialist Dr Hirohisa Okuma of Tokai University in Tokyo, who carried out research in which patients recorded symptoms ahead of an approaching cyclone, which can occur between July and October in Japan.

It’s not known exactly why storms are a trigger for migraine in some people, but it has been suggested decreased air pressure causes electrical and chemical changes in the brain, which can irritate nerves. Dr Okuma thinks it’s highly likely that our inner ear includes a system that detects atmospheric pressure. This has been proven in experiments with animals, in which their sensitivity to air pressure is thought to drive them to seek cover when a storm is imminent.

If you suspect your headaches are caused by changing weather conditions,

Hay fever season now starts earlier because of rising temperatures

Extreme heat or cold affect heart health

try keeping a diary of symptoms, along with weather information. You could also include other common triggers such as menstrual cycle, diet and sleep. The Migraine Trust has good advice on what to monitor, and says bright sunlight, UV rays and high humidity are among environmental factors that are reported to trigger migraines (migrainetrust.org).

LOVE YOUR HEART

Extremes of temperature can affect anyone, but those with existing heart conditions need to take special care when the temperature climbs or falls dramatically. A new cardiovascular risk factor described as ‘non-optimal temperature’ has recently been added to the Global Burden Of Disease study, a worldwide collaboration of experts that assesses health planning.

So, how does temperature affect our hearts? ‘When you get hot, the blood vessels dilate, which means the heart has to work harder, particularly if you become dehydrated,’ explains Julie Ward, senior cardiac nurse at the British Heart Foundation (bhf.org.uk). ‘In cold weather, if body temperature drops, blood becomes thicker, increasing the risk of blood clots.’ Simply staying cool in the heat and drinking plenty of fluids will counter extra strain on the heart.

Losing too much body fluid through sweating and not drinking enough can also lead to heat exhaustion or heat stroke (even if you don’t have heart problems). Symptoms include clammy skin, dizziness, sweating, nausea, and tiredness. Lying down in a cool room, a cool shower and non-alcoholic fluids should help, but if you don’t feel better within 30 minutes or become confused or hot and flushed without sweating, seek emergency medical help.

In cold weather, keeping warm and exercising, such as walking briskly, keeps the blood flowing and increases circulation. If you are sitting for any period, try to move every 20 to 30 minutes, advises Julie.

Increased air pollution due to rising temperatures is also a serious factor that, over time, can cause or exacerbate a range of heart problems. ‘Tiny particles that we breathe in can enter the bloodstream,’ explains Julie. ‘This causes blood vessels to narrow and harden, increasing blood pressure and putting a strain on the heart. It also makes the blood more likely to clot and affects the normal electrical functioning of the heart, which can lead to an abnormal heart rhythm. The latest research shows air pollution causes changes to the structure of the heart muscle at a cellular level, similar to changes that can be seen in the early stages of heart failure, so it has a real impact on heart health.’

Thankfully, there are easy, practical ways we can all significantly reduce our exposure to air pollution. Walking via quieter back roads, avoiding rush hours where possible, seeking green spaces and not exercising outdoors when pollution levels are high, all make a difference. Check local pollution levels at uk-air.defra.gov.uk.

LOOK AFTER YOUR LUNGS

Increased levels of air pollution due to rising temperatures have serious implications for lung health, too, says Dr Andrew Whittamore, GP and clinical lead for Asthma UK and the British Lung Foundation (blf.org.uk) ‘It causes new lung conditions, and worsens existing ones, such as asthma and COPD, and it can even trigger potentially life-threatening asthma attacks,’ he explains. ‘Warmer temperatures could also lead to more mould and pollen, causing more people to experience symptoms if their asthma or lung condition is triggered by these allergies.’

Just as with heart health, it’s important to drink plenty of fluids. ‘Being dehydrated causes the mucus lining the airways to become thick and sticky, slowing down the respiratory system and increasing susceptibility to illness as well as allergies,’ says Dr Whittamore. ‘It also puts other organs in the body under stress.’

You’re more likely to feel breathless on humid days, when the air becomes denser, and also when there’s a drop in air pressure ahead of bad weather, which reduces the amount of oxygen in the air.

‘It’s hard to generalise about the best weather for those with lung conditions, as it is so individual, but the crucial thing is to know your triggers, check pollen forecasts and air pollution levels, and plan ahead,’ says Dr Whittamore.

In addition, we can all easily make changes to reduce how much pollution we produce. For instance, using our cars less, and walking and cycling more.

Meanwhile, next time we’re heading for a heatwave, we need to borrow some Mediterranean lifestyle lessons to keep our houses and ourselves cool. Avoid the midday sun, keep blinds and shutters closed against the heat, and go out early or late in the day.

Keep a diary of symptoms and weather details