||Asthma is a chronic (long term) and potentially fatal disease caused by inflamed airways of the lung which restricts airflow. The red, swollen lining of the air passages increase the sensitivity of airway nerve endings so they become easily irritated. Muscles around the airways become sensitive and start to twitch and tighten which further narrows the airways.
The disease is characterized by recurrent attacks triggered by such things as cold air, pollen, smoke and other types of air pollution. Symptoms include shortness of breath, tightness in the chest, coughing and wheezing. There is no set pattern for these symptoms and they can vary in severity and frequency from person to person and even from hour to hour in the same individual. This makes clinical and objective diagnosis difficult and inconsistent which makes estimating population-based prevalence and severity difficult. However, the methodology of surveys is always improving and their results continue to be a valuable component of understanding population health.
Three million Canadians, including thousands of British Columbians, have asthma. Every year 500 adults and 20 children in our country die because of asthma. That's 10 deaths every week and one of those is from B.C. Health care expenditures in Canada for respiratory disease are 12.18 billion dollars per year (1993 dollars).
In the United States alone, air pollution claims approximately 50,000 lives every year. 10% of these are due to asthma....that's 14 asthma deaths per day. The Centre for Disease Control estimates that more than 15 million Americans suffer from asthma. In the last 15 years, the number of asthmatics in the United States has increased by over 60%. In that same time the number of deaths due to this disease has doubled. It is the only chronic disease, besides AIDS and TB, with an increasing death rate.
Some of us can stand much higher levels of air pollutants than others. Levels of, for instance, particulate matter, nitrous oxides or ozone that would have no apparent effect on non-asthmatics can trigger disastrous effects in those who suffer from asthma. That is reason enough for us to increase sensitivity to how, when and why we are adding pollutants to our air and commit to the avoidance of producing them in the first place.