Risk factors for asthma onset between the ages of 12 and 40. Results of the FENASMA study.

Objectives: To describe the clinical profile of patients with asthma and to identify possible risk factors for its development in subjects over the age of 12.

Patients And Methods: A multicenter study of cases and controls. Recruited for inclusion were case subjects between the ages of 12 and 40 diagnosed with asthma, with an onset of symptoms after the age of 12.