Medical Matters: Over the years, many patients with arthritis have complained of a worsening of symptoms in cold and wet weather. When asked if bad weather conditions contributed to the development of joint disease, my reply was usually no.
Now, however, studies have shown that a simultaneous drop in atmospheric pressure and a rise in humidity create joint stiffness and a worsening of the symptoms of arthritis.
The recent run of cold and wintry conditions is a reminder of the huge influence that weather can have on our health. I have no doubt that the number of fractures seen in hospitals where snow and ice have affected the locality have risen significantly. A study in the latest issue of the Emergency Medical Journal found more than one in 10 attendances at a children's hospital casualty department during a prolonged snowfall were due to accidents with toboggans.
Doctors from the Accident and Emergency Department at the Aberdeen Royal Infirmary in Scotland treated 25 boys and two girls for sledging injuries during a two-week period of bad weather. The commonest problem was leg injury followed by damage to the arm. Four of the children, aged between two and 13, sustained a head injury.
In total eight of the 46 children required hospital admission. 30 per cent of those injured did so as a result of falling off the sledge, while 26 per cent were injured following a collision with static objects such as trees or fences. None of the injured children wore protective head gear.
Clearly we cannot prevent snowfall. But an interesting initiative in Britain by the Met Office has made a difference to the deployment of medical services in response to weather extremes.
The Met Office has appointed a medical consultant to assist it in producing a new type of weather forecast designed to help the NHS predict peaks and troughs in the demand for medical services. Dr William Bird, a former GP, has helped the meteorological service predict weather related surges in demand. A project called "Forecasting the Nation's Health", which involved the collection of data from hospitals and GP out-of-hours co-ops on a daily basis, has provided an up-to-date picture of the demand for services. When combined with weather data, snowfall, air quality and wind measurements, it has enabled the new project to offer health weather forecasts to hospitals.
In the first year of the project the new forecasts were found to be 50 per cent accurate. By the winter of 2001 the accuracy rose to an average of 65 per cent and even reached 100 per cent in some regions. Last year, almost half the country was being covered; the meteorological predictions enabled hospitals to make significant savings. In one case £400,000 was saved in a three-week period by rescheduling non-urgent operations and by calling up extra staff in some departments while cutting back in others.
The Royal Berkshire Hospital used the weather updates to organise an extra 100 non-urgent operations in December, 2000. This 10 per cent increase in activity was achieved on the back of accurate forecasting of an unusually mild period of weather.
As well as improving efficiency the initiative has the potential to minimise the suffering of patients who are now expected to lie for days on trolleys in accident and emergency departments because of bed shortages.
Weather can have a direct effect on our health by changing our blood system and even our brain chemistry. Cold air raises blood pressure and causes platelets in the blood to stick together. As a result people with severe coronary artery disease are more likely to have a heart attack. Those with lung disease such as chronic bronchitis or asthma often notice that breathing becomes more difficult as temperatures drop. This is because the cold air triggers constriction of the airways.
For every degree the temperature drops below 18 degrees Celsius there is a two per cent increase in death rates. Two days into a cold snap and the incidence of heart attack rises; three days later and the number of strokes increase.
One of the most important ways to prevent ill-health during a cold snap is to ensure that homes are well heated. By keeping warm, the chances of body temperature dropping too low are minimised. Regular exercise also helps because it improves circulation, lowers blood pressure and helps to regulate temperature. If you have difficulty exercising because of disability then the next best thing is to wear several thin layers of clothes in order to minimise heat loss.
The future possibilities of health weather forecasting are exciting. It may even be possible to prevent surges in illness by predicting weather likely to exacerbate certain conditions. The sky is literally the limit for an initiative like this.