Age as influence in the adrenergic/cholinergic bronchomotor response.

Abstract

Changes of pulmonary mechanisms, receptor population and nervous control of the airway, that occur with ageing, are responsible for the different clinical presentation of pathologies like asthma, as well as different efficacy of bronchodilator therapeutics in the aged patient. To be explained are the effects of age in the bronchodilator response to beta-mimetics and cholinergics and the existent evidence is discordant. Some comparative studies of that pharmacological response, made on asthmatics, have shown an efficacy decline with age. Others didn't find any significant difference.Individual evaluation of bronchodilator response in individuals of different age groups to salbutamol and ipratropium bromide.Three groups of 12 patients - witness group (W), young healthy individuals; control group (C), elderly individuals without respiratory pathology; study group (S), elderly individuals with bronchial asthma - were submitted to functional ventilator evaluation followed by a bronchodilator test in two consecutive days (one day with salbutamol (s), other with ipratropium bromide (b). In S all were in a stable period, without anti-asthmatic medication in the previous 24 hours. Plethismography and spirometry followed ATS/ERS, 2005 criteria. To evaluate the bronchomotor response we used as criteria an increase of 12% or 200 ml in FEV1 or in FVC, after inhalation of 40 mcg of ipratropium bromide or 200+200 mcg of salbutamol.The variability of response was constant. With age, (W Vs C) there was an increase on negative responses to both drugs (4 Vs 8); a decrease on responses simultaneously positives to s and negatives to b (4 Vs 2) and an increase on responses simultaneously positives to b and negatives to s (0 Vs 1). With age and associated disease (W Vs S) the number of responses simultaneously positives to both drugs has raised (1 Vs 3); the number of responses simultaneously negatives to both drugs kept constant (4 Vs 4); the number of responses simultaneously positives to s and negatives to b decreased (4 Vs 1); number of responses simultaneously positives to b and negatives to s increased (0 Vs 2).An individual analysis of bronchomotricity in different groups leads to the conclusion that, with age, there was a decrease in bronchial lability, independently of the used drug. Globally, in aged asthmatics, the bronchial response was superior to the healthy ones, as expected. The individual analyses of the positive bronchodilatorresponses lead to the conclusion that, with age and disease, the ipratropium bromide showed an improvement in bronchomotricity, contrary to salbutamol. Such fact may be explained by the already, but not consensual, description of the decreasing efficacy of adrenergic drugs with age, aggravated by the chronic use of long acting betamimetics.