Health The heat is on Its summer, and while most of us love a bit of sunshine, the warmer weather can affect some people with arthritis P eople with arthritis often say that they can predict the weather based on how their joints feel. Some notice their pain and stiffness flares up in the cold and wet winter months, while others find hot and humid summer weather can make symptoms worse. Dr Alastair Dickson, GP and health economist with an interest in rheumatology and arthritis, and trustee of the Primary Care Rheumatology and Musculoskeletal Medicine Society, says that some people are more sensitive to the weather than others. It is unknown why weather affects arthritis pain, he says. One theory is that people are less active in cold, damp weather and keeping active is known to help relieve arthritis pain. An alternative theory is that changes in barometric pressure [pressure caused by the weight of the air outside] affect the pain you feel. Temperature sensitivity is a common symptom of fibromyalgia, and extremes in temperature, whether it be hot or cold, can trigger flare-ups. A study found that damp and windy days with low atmospheric pressure increased the chances of experiencing more pain than normal by around 20 per cent READ MORE In October 2019, the Cloudy with a Chance of Pain study, led by consultant rheumatologist Professor Will Dixon at the University of Manchester, assessed how weather affected more than 13,000 people in the UK with long-term health conditions, including arthritis and fibromyalgia. Participants used a smartphone app to record their daily symptoms and things that affected their pain levels (such as sleep patterns and daily exercise), while GPS in their phones provided accurate weather reporting. The study, funded by Versus Arthritis, found that damp and windy days with low atmospheric pressure increased the chances of experiencing more pain than normal by around 20 per cent. Barometric pressure may affect your joints more than humidity, rainfall and temperature. According to the Met Office, high pressure tends to cause fine, warm weather, while low pressure can lead to prolonged rainfall and flooding. Scientists know muscles, bones and tendons get bigger and smaller in response to atmospheric changes, but exactly how and why barometric pressure changes affect the joints is unclear; this could be related to the pressure of the fluid oiling your joints or increased nerve sensitivity. Your response may also depend on the type of arthritis you have. According to Professor Karen Walker-Bone, professor of occupational rheumatology at the University of Southampton, people with osteoarthritis generally prefer warm and dry weather, while those with rheumatoid arthritis tend to prefer the cooler weather. A small Norwegian study in 2019 of 48 people with fibromyalgia found that lower barometric pressure was associated with increased pain, with higher emotional stress levels making the pain even worse. Research in Belfast in 2015, looking at 133 patients, found people with rheumatoid arthritis had fewer joint symptoms (tenderness and swelling), and lower levels of inflammation, in sunny and less humid conditions. Some people are more sensitive to the weather than others, but it is unknown why it affects arthritis pain Avoiding a flare up Its impractical to move to an arthritis-friendly climate, but you can take certain steps to ease summer-weather symptoms. Keep an eye on the forecast so that you can be prepared, and carry on with gentle exercise, such as stretches or yoga, even if your joints feel a little sore. Many people say their joint stiffness gets worse in very hot weather, and that may be at least partly related to fluid retention, says Dr Carol Cooper, GP with an interest in rheumatology. Keeping cool, staying in the shade and wearing natural fabrics can help. Gentle swimming can also relieve some of the symptoms, but a lot depends on the individual. If your hands, feet and ankles swell up a little in hot and humid weather, this isnt usually anything to worry about. But if its very uncomfortable, speak to your GP, especially if you have a heart condition. Staying active (or even just moving your legs when youre sitting down) will help to keep your blood flowing. Aim to consume less salt salt makes your body retain extra water, while drinking more water can dilute salt levels. To ease the swelling, raise your feet or put a pillow under your ankles while youre in bed. Professor Walker-Bone recommends using ice packs or having cool showers. Adjust the temperature of the water to suit your personal preference, she says. If you use ice, remember to wrap it in a tea towel first so it doesnt burn your skin. Cooling gels and sprays may also help. If youre sweating more than usual, this can make you dehydrated, so keep topping up your fluid levels with regular drinks. Dehydration can cause muscle cramps and muscle and joint pain in anyone, says Dr Dickson. The effects of dehydration are likely to be worse if you already experience joint and muscle pains, while dehydration is a known risk factor for a gout flare. Sunshine benefits Vitamin D is essential for healthy bones, teeth and muscles, as well as your immune system. You get most of your vitamin D from direct sunlight when your skin is exposed to ultraviolet (UV) rays. According to Cancer Research UK, the length of time you need in the sun to make enough vitamin D depends on skin type, time of day or year, and where you are in the world. There are no set guidelines on how much time is needed in the sun, but those with lighter skins may need just 10 minutes of sunlight every day in the UK, while those with darker skin may need around 25 minutes. There are guidelines on vitamin D supplementation for everyone in the UK, says Professor Walker-Bone. But if youre worried about your vitamin D levels and joint pain, its important to get advice from your GP or rheumatology team. They can check your vitamin D levels, ideally in the winter months when they are likely to be lower. Some people find their psoriasis gets better when theyre out in the sun, but more research is needed to see if sunlight helps psoriatic arthritis. Natural sunlight can help skin psoriasis, but doesnt seem to help joint symptoms, says Professor Walker-Bone. Many people with psoriatic arthritis dont have very bad skin, so PUVA treatment (UVA light and special tablets) cant help. Skin protection While its important to get vitamin D, too much sun exposure can cause sunburn and increase your risk of skin cancer. Some medications for arthritis can also make your skin more sensitive to sunlight. Spend time in the shade, especially between 11am and 3pm between early April and late September in the UK. Cover up with lightweight clothing, a wide-brimmed hat and wrap-around sunglasses. Use a sunscreen with at least SPF15 and four or five UVA stars: apply it regularly and generously on all exposed areas of your skin. istock.com / Mykola Sosiukin istock.com / seb_ra Weather changes istock.com / Imgorthand Words: Victoria Goldman Vitamin D is essential for healthy bones, teeth and muscles, as well as your immune system