Background: Diffuse parenchymal lung disease (DPLD) is not an uncommon problem in clinical practice. Although the exact prevalence of DPLD in India is not known, the relative etiological distribution in DPLD in India has been reported. There has been no information as regards the seasonality of the disease.
Patients and methods: The archive of the Institute of Pulmocare and Research, Kolkata, was searched for the number of new patients registered at the outpatient department to a single consultant (practicing in the same style on appointment only) over years from 2009 to 2019. The attendance (absolute and relative) was arranged year wise and then month wise to look for the annual and seasonal trends, if any.
Results: A total of 2226 patients were registered from 2009 to 2019. There has been a steady increase in both the absolute number (104 in 2009 to 204 in 2019) and the relative percentage of attendance (4.36% in 2009 to 6.9% in 2019) of new registration of DPLD patients over the years. Regarding seasonal variation, two consistent peaks in attendance have been observed as December-January and April-May over the years with dips in February and September; the first being more consistent then the latter.
Conclusions: The increase in relative attendance in the DPLD patients over the years needs further investigation to establish a rising trends in incidence and prevalence of DPLD. The unequivocal trend in seasonal variation needs attention and further research.
Keywords: Connective tissue disease-interstitial lung disease; diffuse parenchymal lung disease; high resolution computerized tomography; hypersensitivity pneumonitis.