Incidence and Triggers of Asthma Exacerbations Attended in the Emergency Department as a Level of Care Indicator (ASMAB III, 2005 and ASMAB IV, 2011)

Diesel exhausts particles: Their role in increasing the incidence of asthma. Reviewing the evidence of a causal link

Exposure to air pollutants has been correlated with an increase in the severity of asthma and in the exacerbation of pre-existing asthma. However, whether or not environmental pollution can cause asthma remains a controversial issue. The present review analyzes the current scientific evidence of the possible causal link between diesel exhaust particles (DEP), the solid fraction of the complex mixture of diesel exhaust, and asthma. The mechanisms that influence the expression and development of asthma are complex. In children prolonged exposure to pollutants such as DEPs may increase asthma prevalence. In adults, this causal relation is less clear, probably because of the heterogeneity of the studies carried out. There is also evidence of physiological mechanisms by which DEPs can cause asthma. The most frequently described interactions between cellular responses and DEP are the induction of pulmonary oxidative stress and inflammation and the activation of receptors of the bronchial epithelium such as toll-like receptors or increases in Th2 and Th17 cytokines, which generally orchestrate the asthmatic response. Others support indirect mechanisms through epigenetic changes, pulmonary microbiome modifications, or the interaction of DEP with environmental antigens to enhance their activity. However, in spite of this evidence, more studies are needed to assess the harmful effects of pollution - not only in the short term in the form of increases in the rate of exacerbations, but in the medium and long term as well, as a possible trigger of the disease.

Epidemiological profile of smoking and nicotine addiction among asthmatic adolescents

OBJECTIVE

Despite the harmful effects of cigarette smoking, this habit in asthmatic adolescents continues to be a health problem worldwide. Our objectives were to determine the epidemiological profile of smoking and the degree of nicotine dependence among asthmatic adolescents.

STUDY DESIGN

Through a cross-sectional investigation, 3383 adolescents (13-19 years of age) were studied.

METHODS

Information was collected using a previously validated questionnaire. Two study groups of adolescent smokers were formed: one composed of asthmatic adolescents and the other of healthy youths.

RESULTS

Asthmatic adolescents were found to be more likely to smoke (21.6% vs 11.8%) and to have some degree of nicotine dependence compared with healthy adolescents (51.6% vs 48.8%). The most important characteristic of smoking in asthmatic adolescents was found to be an onset before 11 years of age due to curiosity about cigarettes. Asthmatic youths continue smoking because this habit decreases their anxiety and stress. Adolescents know that smoking is addictive and often smoke on waking up in the morning or when they are sick. Yet, these adolescents do not consider smoking to be a problem.

CONCLUSION

In this study, curiosity about cigarettes was the primary reason why asthmatic adolescents smoked for the first time and developed a greater dependence to nicotine compared with healthy adolescents. Moreover, the findings show that many of the factors that favour the development of smoking are preventable, given that they are present in the family and social environment.