Relation between positive small air ions, weather fronts and pulmonary function in patients with bronchial asthma.

Some patients with bronchial asthma report increased symptoms in association with weather fronts. It has been reported that a rise in positive small air ions occurs several hours before other evidence of a storm front, and it has been suggested that the increase in these ions might be responsible for the changes in clinical status reported by such patients. Twelve patients were selected on the basis of a history of weather-induced worsening of asthma. They measured pulmonary functions four times daily at the same time that measurements of small air ions and other meteorologic parameters were obtained. Two episodes of inclement weather were monitored during the study period. The mean peak flow rates in this group of patients did not vary significantly with the changes in ion levels or other meteorologic factors which resulted from the passage of these weather fronts.