Background: Bronchial asthma is the most common chronic disease in children, producing the highest absenteeism among children and adults.
Objective: To determine the relation between respiratory function in asthmatic children and contaminant and climatic environmental factors.
Material and methods: It was performed a study with 26 asthmatic patients, from the Immuno-Allergies Department of the Specialties Hospital no. 71 of the Centro Medico Nacional Torreon, with an 8-month-follow-up. By a home monitoring, subjects determined their peak expiratory flow (PEF) twice a day: PEF1: in the morning, at getting up without or before medication, and PEF2: at night, before sleeping without or before medication.
Results: From June to August 1995, as well as from September to November 1995, a relation between pulmonary function, measured by PEF1 and PEF2, and some of the palinologic families or species studied was not found. On the other hand, from December 1995 to February 1996 a significant relation between the concentration of pollen's particles of Chenopodiaceaes and Amaranthaceaes and the difference between PEF1 and PEF2 (Difpef), with a p value < 0.05.
Conclusions: Environmental Chenopodiaceaes' and Amaranthaceaes' pollen is related to a variability of 0.0075 L/min of Difpef for each grain of pollen/m3 in the environment during winter, after rain time of the Comarca Lagunera.