Asthma Prevalence and Risk Factors in Latin America

Asthma is a common and sometimes fatal chronic disease, and its prevalence has been increasing in all regions of the world, especially among children. The International Study of Asthma and Allergies in Childhood (ISAAC) Phase I has made reliable data available regarding asthma prevalence in Latin America. Current prevalence for wheezing, exerciseinduced wheezing, and severe episodes was 17.0%,19.3%, and 4.6%, respectively, for children aged 13-14 years, and 19.8%, 9.2%, and 4.6%, respectively, for children aged 6-7 years. In Latin America, prevalence showed a trend to be lower in centres located at the northern and southern extremes and higher at centres at tropical latitudes. The significantly higher relative risk for asthma symptoms in centres with hot and humid climate would suggest some relationship between tropical climate and higher prevalence of asthma. The prevalence of asthma symptoms tended to be higher in poorer areas, suggesting that socioeconomic status is a major risk factor for the high prevalence of asthma in Latin America. The Asthma Insights and Reality in Latin America (AIRLA) survey, carried out in 2003, documented an unacceptably high level of patient morbidity from asthma throughout Latin America. The vast majority of patients were not receiving appropriate diagnosis, therapy and monitoring, and were failing to achieve the goals for asthma management set out in the Global Initiative for Asthma (GINA) guidelines. This places a great burden on the health care system and society as a whole, with substantial loss of work and school activity. Correspondence: Dr Hugo E Neffen, Respiratory Medicine Unit, 'O. Alassia' Children's Hospital, Santa Fe, Argentina. E-mail [email protected] Phase III the highest value was noted in Costa Rica (32.1%) and the lowest in Mexico (8.6%). In the 13-14 year age-group, the world prevalence of asthma symptoms changed by 1 SE or more in most centres (77%). Of the 82 centres with changes, about equal numbers showed an increase (42) and decrease (40) in prevalence. For lower mean prevalence values, more centres showed increases in prevalence of 1 SE or more, but for centres with higher mean prevalence, decreases in prevalence of 1 SE or more were more common. In Latin America the situation is different because within the 16 centres compared, 8 centres showed an increase, 5 showed no change and only 3 centres showed a decreased prevalence. According to ISAAC Phase III in the adolescent group the highest value was noted for Perú (26%) and the lowest for Mexico (6.6%).