The Global Impact of Asthma in Adult Populations.

Asthma is a disease characterized by chronic airway inflammation, leading to intermittent symptoms of wheeze, dyspnea, cough and chest tightness in combination with variable expiratory airway obstruction. Clinical diagnosis is usually established based on the presence of symptoms and documented variability in expiratory airflow limitation as measured by pulmonary function testing. Presently, asthma is a major chronic disease affecting approximately 334 million people worldwide. The epidemic spares no age group, race or ethnicity; however ethnicity and socioeconomic status do influence the prevalence, morbidity and mortality of asthma in the United States and various countries throughout the world. Moreover, asthma places a huge burden at the societal, financial and health-care levels of multiple nations.