Estudi de casos i controls sobre els factors de risc i la gravetat de l’asma en una població escolar

Background. Asthma is the most common chronic disease in childhood. Its prevalence has increased over the last few decades. Objective. The aim of our study was to define the influence of known risk factors for asthma and its severity in a group of school- aged patients. Method. Prospective observational case-control study of asthmatic patients attended in our allergy outpatient department and healthy controls. Data were collected through questionnaires and review of medical records. Subsequently, a statistical analysis was perfor- med by univariate and multivariate regression. Results. Thirty-two healthy individuals, with an average age of 10 years and male predominance [59% (n=19)] and 107 asthmatic children, with an average age of 9 years and male predominance [62.6% (n=67)] were included. Thirty-two percent (n=34) of the asthmatic children presented persistent asthma and 9% (n=10) poor control of the disease. Sensitization to dust mites was the most prevalent [86% (n=92)]. In the statistical analysis between the risk factors studied in both populations, the only significant difference was the history of recurrent wheezing of children aged 3 years or younger (p<0.001). Associations were also observed between severe asthma and a history of frequent viral lower respi-atory tract infections (p<0.001), respiratory syncytial virus (RSV) infection (p<0.05) and sensitization to fungi (p<0.05). Conclusions. The history of recurrent wheezing in the first 3 years of life is the most important risk factor for the presence of asthma in children in school age. This factor, RSV bronchiolitis and sensitization to fungi were related to most severe asthma.