ARCHIVE
Issue 15
December 19, 2001

Is Weather Affecting Your health?

The weather has long been suspected of affecting people's health. Cold damp days can mean aching bones and joints for arthritis sufferers and a long hot spell can result in lost workdays for migraine sufferers. Although these effects are common knowledge, they tend to be dismissed as coincidence or folklore. But there is mounting evidence that certain health problems are aggravated or even brought on by the weather.

Assessing the relationship between weather and health can be difficult. This is partly because the weather changes everyday which brings different weather factors into play. But researchers using weather information in their studies on human health have made some interesting connections and have confirmed what many people have long suspected: weather affects health.

The studies show that migraines are more prevalent in locations where warmer air is moving in. Chronic pain sufferers are most affected by changes in temperature, humidity, precipitation and sudden changes in the weather. Arthritis acts up with strong atmospheric cooling and is influenced by dampness.

Researchers have also found other important connections. The rate of heart attacks increases with changes in air masses. Depression is more prevalent in the warm sector of a weather system. Blood pressure is affected by outside temperature and the rate at which blood clots also changes depending on the weather. In fact, the entire human body appears to be weather sensitive in one way or another.

The German weather service currently incorporates these findings in their weather forecasts. It has developed a weather-health index, which predicts the degree of risk of particular ailments across the country. The program began in 1985 and by 1994 they were producing weather-based health forecasts which are aired alongside the weather forecasts . Physicians in Germany have indicated that the bio-weather forecasts are very useful during consultations with their patients.

In the United Kingdom, they have applied this knowledge in a slightly different manner. During the 2000-2001 winter season, the meteorological office and the department of health conducted a pilot study forecasting hospital workload based on the probability of increased incidences of heart attacks, respiratory difficulties, falls and broken bones linked to the weather. During a two-week period which forecasted a slower than normal workload, one hospital was able to schedule an additional 150 elective surgeries at a savings of $1.2 million.

A Weather and Health map for North America

A computer-generated, weather-health map of North America has been developed as a prototype. It combines weather factors known to affect health such as temperature, humidity, atmospheric pressure and wind. The MediClim^TM is an index which defines 14 different weather conditions linked to health ailments. Work is continuing to bring this prototype into the public domain.

Using Weather Information to Manage Illness

Understanding the links between weather and health can be both practical and beneficial. The hope is that patients will be able to use the information provided by the weather forecast to manage their illness and plan their daily activities. For example, under known problematic weather conditions and on the advice of their personal physicians, migraine sufferers could avoid other migraine triggers, such as red wine and chocolate. Arthritis sufferers could take their medication as a preventative measure before their pain sets in. And so, when weather forecasters and the health care system are able to adapt this new information, Canadians will have a new tool to better manage those difficult "weather" days.