[Epidemiology of asthma]

Abstract

Asthma epidemiology aims to provide answers to the following questions: what is the prevalence? what are the consequences? what are the risk factors of asthma? Questionnaires indicate that asthma prevalence averages 6 to 8% whereas assessment of bronchial reactivity reveals that approximately 15% of the population exhibit bronchial hyperesponsiveness; these figures have been increasing in many western countries. Asthma is an important cause of impairment in children physical development, school-related problems along with increased number and duration of hospitalizations. Asthma mortality averages 3/100,000 in France and is mainly focused on people more than 50 years old; its increase is very likely in some countries, but is still controversial in France. Environmental and socio-economic factors play a major role in the development of asthma and genetic factors are now under investigation. Although both understanding and drug treatment of asthma have dramatically improved in the recent past, no positive change has been observed so far in terms of morbidity and mortality. Nevertheless, knowledge of factors specific to France requires further investigations.