Breathlessness is often dismissed as ageing, lack of fitness, pollution or a lingering respiratory infection. A dry cough may be ignored for months. Many people simply adapt by walking more slowly, avoiding stairs, pausing during familiar activities or taking more breaks.
When these symptoms persist or gradually worsen, they should not be ignored. They may be signs of interstitial lung disease (ILD), a large group of conditions that affect the lung tissue itself. In some ILDs, inflammation or injury leads to fibrosis, which means permanent scarring of the lungs. The scarred lungs become stiffer and less able to transfer oxygen into the blood, making breathing and everyday activity increasingly difficult1.
Understanding ILD, IPF and progressive pulmonary fibrosis
ILD is not one disease, and the terms ILD, pulmonary fibrosis, idiopathic pulmonary fibrosis (IPF) and progressive pulmonary fibrosis (PPF) are related but not interchangeable. IPF is lung scarring for which no cause is identified after a thorough evaluation, and it often worsens over time. PPF describes a pattern in which fibrosis caused by another ILD continues to worsen despite appropriate management. The underlying condition, extent of scarring and rate of progression may differ from person to person1.
Some ILDs are associated with autoimmune diseases. Others may be linked to repeated exposure to bird's mold, damp environments, air-coolers, farming conditions or workplace dust. Sharing a complete home, work, medical and medication history can therefore provide important clues. An exposure does not by itself prove the cause, but it can guide further investigation. In the prospective ILD-India registry of 1,084 patients across 27 centers in 19 cities, hypersensitivity pneumonitis was the largest diagnostic category, and air-cooler exposure was frequently reported within that group2.
{{/usCountry}}Some ILDs are associated with autoimmune diseases. Others may be linked to repeated exposure to bird's mold, damp environments, air-coolers, farming conditions or workplace dust. Sharing a complete home, work, medical and medication history can therefore provide important clues. An exposure does not by itself prove the cause, but it can guide further investigation. In the prospective ILD-India registry of 1,084 patients across 27 centers in 19 cities, hypersensitivity pneumonitis was the largest diagnostic category, and air-cooler exposure was frequently reported within that group2.
{{/usCountry}}Why diagnosis may take time
The early symptoms of ILD are common to many heart and lung conditions. Breathlessness, persistent dry cough, fatigue and reduced exercise capacity can initially resemble asthma, chronic obstructive pulmonary disease, pneumonia, tuberculosis or reduced fitness. This overlap can make ILD difficult to recognize, particularly when symptoms develop gradually.
A study of 100 people with ILD from rural and semi-urban India reported an average interval of 2.2 years from the start of symptoms to diagnosis. Pneumonia, COPD or asthma, and tuberculosis were among the earlier labels recorded. Its practical message is more important: when symptoms continue, become worse or do not respond as expected, the diagnosis may need to be reviewed3,4.
These findings reinforce a practical public-awareness message: if respiratory symptoms continue, worsen or do not respond as expected, the diagnosis may need to be reviewed, and specialist assessment considered.
Why the right referral and combined expertise matter
Not every person with cough or breathlessness has ILD. However, worsening symptoms, declining ability to exercise, concerning test results or an unexpected response to treatment may warrant referral. Depending on the suspected cause, evaluation may involve pulmonologists and rheumatologists.
No single symptoms, scan or blood test answers every ILD question. An India-led prospective virtual programme brought specialists together to review 127 anonymized ILD cases from 24 Indian referral centers. After discussion, 23% of the cases were reclassified. The point for patients is straightforward: a combined expert review can sometimes refine the diagnosis and help the care team choose a more appropriate path forward2,6.
Diagnosis is the beginning of continuing care
Receiving an ILD diagnosis is not the end of the journey. Some fibrotic ILDs remain stable, while others progress. Regular follow-up helps the care team look for changes in symptoms, everyday activity, lung function and imaging, and decide whether management needs to be adjusted. Patients should ask which ILD has been diagnosed, what changes should prompt an earlier appointment and how progression will be monitored1.
Awareness must be matched by access
Public awareness can help people recognize persistent symptoms, but it must be supported by clear referral pathways, specialist capacity and access to appropriate tests. Virtual multidisciplinary platforms may extend specialist input across geography, while local capability and referral networks remain essential. National data initiatives can also improve understanding of regional patterns, diagnostic delays and disease progression.
Practical access affects care after diagnosis too. A qualitative study in Delhi and Noida involving 20 people living with IPF, 10 caregivers and 10 healthcare workers identified travel distance, limited-service availability and shortages of trained professionals as barriers to pulmonary rehabilitation7.
Recognise change and act early
Pulmonary fibrosis can be serious and, in some forms, life-threatening. The purpose of awareness is not to create fear. It is to help people notice changes that persist: a dry cough that does not settle, increasing breathlessness, more pauses during a familiar walk or everyday activities becoming harder than before.
People experiencing these changes should seek medical advice and share a complete medical, occupational and environmental history. For those already diagnosed, continued follow-up is equally important. Timely evaluation, an accurate diagnosis and coordinated specialist care can help ensure that each person receives management suited to the specific ILD and how it behaves over time.
The article is written by Dr Arjun Khanna, Associate Professor, Principal Consultant and Head of The Department, Department Of Pulmonary Medicine, Amrita Hospital and School of Medicine, Faridabad.
This article has been issued in public interest on behalf of Boehringer Ingelheim India Pvt Ltd. by HT Brand Studio and does not have journalistic/editorial involvement of Hindustan Times. Please consult to your registered medical practitioner for information or guidance or any questions related to the topic. The views and opinions of registered medical practitioner expressed in this article do not reflect the opinions of Boehringer Ingelheim.
References
1. Raghu G, Remy-Jardin M, Richeldi L, et al. Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline. Am J Respir Crit Care Med. 2022;205(9):e18-e47. doi:10.1164/rccm.202202-0399ST. Open source
2. Singh S, Collins BF, Sharma BB, et al. Interstitial Lung Disease in India: Results of a Prospective Registry. Am J Respir Crit Care Med. 2017;195(6):801-813. doi:10.1164/rccm.201607-1484OC. Open source
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6. Mehta AA, Rajan S, Ahmed S, et al. Virtual multidisciplinary discussion across borders for interstitial lung disease: a prospective, multicentre study from India, the UK, Greece and Sri Lanka. BMJ Open. 2025;15:e110693. Open source
7. Hanif H, Ahmed O, Manifield J, et al. Understanding the lived experience of idiopathic pulmonary fibrosis and how this shapes views on home-based pulmonary rehabilitation in Delhi, India. Chronic Respir Dis. 2024;21:14799731241258216. doi:10.1177/14799731241258216. Open source