Response to comments on Value of past clinical history in differentiating bronchial asthma from chronic obstructive pulmonary disorder in male smokers presenting with shortness of breath and fixed airway obstruction.

Sir,

We thank Ahmed et al.[1] for their keen interest in our article “Value of past clinical history in differentiating bronchial asthma from chronic obstructive pulmonary disorder (COPD) in male smokers presenting with shortness of breath (SOB) and fixed airway obstruction”.[2]

In their comments on this article, Ahmed et al.[1] have discussed the current concepts on pathogenesis and molecular biology of asthma, COPD and a newly recognized subgroup “the overlap syndrome”.[3456789] These are now established facts but the learned readers of this journal are also aware that in routine practice, clinicians have to differentiate asthma from COPD on the basis of their clinical judgement and spirometry and where such differentiation is not possible, a diagnosis of COPD or overlap syndrome is made. Facilities for estimation of biological markers including IL-4, IL-5 and IL-13 or the sputum eosinophilia are limited to a few tertiary medical centers and it is neither feasible nor practical use these markers in differentiating these disorders. Its use, at best, is limited to experimental studies/clinical trials.

Further, our intention while planning this study was to explore simple clinical criteria that can be used in routine clinical practice to differentiate asthma from COPD in patients presenting with fixed airflow obstruction with the use of the past clinical history, more so in male smokers.[1] Obviously such clinical criteria can not be foolproof and a few patients with possible overlap syndrome might escape such differentiation. This limitation apart, it was possible to separate out majority of asthma patients from COPD with the use of clinical criteria devised by us to diagnose asthma in such a difficult clinical scenario. It was neither the aim nor the intention of the authors of this study to explore the background for future trials including those for the upcoming therapies like anti-interleukin 5 monoclonal antibodies.