Abstract
SAMA (Short Acting Muscarinic Antagonist) has been said to be superior to SABA (Short Acting Beta Agonist) in COPD whereas SABA is preferred bronchodilator in asthma patients. In practice however we observe that the response is variable for individual patient. Therefore we evaluated improvement in FEV1 in 27 persistent asthmatics and 27 COPD patients in response to inhaled SABA (Salbutamol) and SAMA (Ipratropium) on separate days. These patients were in remission with no exacerbation or change of regular treatment in last 4 weeks. The washout period of their regular treatments was adhered to, before performing their spirometries. SABA produced mean increase of 16.66% and 401 ml in FEV1 of asthmatics vs. -1.44% and -15 ml change in FEV1 of COPD patients. SAMA produced 4.07% and 161 ml increase in FEV1 in asthmatics vs. 8.59% and 166 ml in COPD patients. The similar increase in FEV1 in ml in response to SAMA was more significant in FEV1% due to lower baseline FEV1 in COPD patients. An interesting fact observed was that with the increasing duration of Asthma and COPD, the reversibility with SAMA sequentially increased. With a cut off of more than 8 years of duration of disease, the average improvement in FEV1 in response to SAMA was 453ml (vs. 77 ml in less than 8 year duration) in asthma and 222 ml in COPD, whereas there was no significant change in response to SABA in both groups. There was no correlation with patient's age or baseline FEV1 value. We conclude that inhaled muscarinic antagonists can be a beneficial adjunct to beta agonists in persistent asthmatics with longer duration of asthma.
- © 2012 ERS
