COPD: Causes, Spirometry Staging & Treatment

What COPD is

COPD (chronic obstructive pulmonary disease) is a chronic, progressive lung condition in which narrowed, damaged airways and loss of lung elastic recoil cause persistent airflow limitation. Smoking causes about 85% of cases, but about 15% occur in never-smokers — from alpha-1 antitrypsin deficiency, occupational dust or chemical exposure, or biomass cooking-fire smoke.²

It cannot currently be cured, but it is highly manageable: the right treatment plan slows progression, cuts exacerbations and improves daily life. A key distinction from asthma is reversibility — asthma's airflow limitation largely reverses with bronchodilators, while COPD's is fixed.

How COPD is usually evaluated

COPD cannot be diagnosed on symptoms or X-ray alone: spirometry (lung function testing) is required. The key diagnostic number is the FEV1/FVC ratio — the forced expiratory volume in one second divided by the total exhaled volume. In healthy lungs FEV1 is at least 70% of FVC; in COPD the ratio falls below 0.70 after bronchodilator use, because obstruction reduces FEV1 disproportionately.

Blood tests support assessment and guide exacerbation care: a full blood count (chronic low oxygen can raise red cell count; anaemia worsens breathlessness and is common), arterial blood gas for oxygen and CO2 levels, alpha-1 antitrypsin level to rule out hereditary deficiency, and CRP or procalcitonin during exacerbations to help distinguish bacterial from viral triggers.³⁴ A bronchodilator reversibility test separates COPD from asthma: COPD shows minimal improvement after salbutamol, asthma typically shows significant improvement.

Your next steps after a COPD diagnosis

Diagnosis is the start of a management plan. Work through these with your doctor:

1. Stop smoking — the highest-impact step. It is the only intervention that slows disease progression, and it helps at any stage. Ask about cessation support rather than going it alone.
2. Confirm the spirometry picture. Make sure the diagnosis rests on post-bronchodilator spirometry, and ask your GOLD stage — then remember that symptoms and exacerbation history, not the FEV1 number, now drive treatment choices.
3. Ask about pulmonary rehabilitation. An 8–12 week programme of exercise, education and breathing techniques reduces breathlessness and hospital readmissions — among the most effective non-drug interventions available.¹
4. Get a written exacerbation action plan. Know your warning signs — increased breathlessness, change in sputum colour (green/yellow suggests infection), worsening cough — and what to do first when they appear.
5. Discuss oxygen and vaccinations. Long-term oxygen therapy is for resting oxygen saturation below about 92% on air; ask too about flu and pneumococcal vaccination, since respiratory infections trigger exacerbations.
6. Know when it is urgent. Seek urgent care for severe breathlessness unrelieved by reliever inhalers, blue lips, confusion, or inability to complete sentences.

How COPD severity is graded

Spirometry both confirms COPD and grades it. A post-bronchodilator FEV1/FVC ratio below 0.70 confirms persistent airflow limitation; the FEV1 percentage of predicted then sets the GOLD grade:

These are approximate bands, not quotes: prices vary by city and lab. Where possible, choose a NABL-accredited lab.

Practical notes

A simple symptom diary pays off: note breathlessness, cough and sputum changes, how often you reach for your reliever inhaler, and any flare-ups with their dates. Doctors use this record to judge whether your treatment is working and when to step it up.

Come prepared with your smoking history (how much, for how long, when you quit), any long-term exposure to dust, fumes or indoor cooking smoke, your vaccination status, and a list of other conditions — heart disease in particular, since it shares symptoms with COPD.

Smoking cessation is the single most important step your doctor will discuss — quitting slows the decline in lung function at any stage. Pulmonary rehabilitation programmes, regular walking as advised, flu and pneumococcal vaccines, and learning correct inhaler technique are the other pillars worth discussing.

Spirometry is usually repeated about once a year, or sooner if your symptoms change. Many doctors also give you a written action plan for flare-ups: which medicines to increase, and exactly when to seek urgent care. Ask for one if you do not have it.

In India

In India, spirometry typically costs around ₹800–₹2,000 at private labs and hospitals, though prices vary by city and facility. A chest X-ray, if advised, usually adds a few hundred rupees — ask for the full estimate when the tests are ordered.

Spirometry quality depends heavily on the technician coaching you through it, so a reputed pulmonary function lab matters more than the cheapest option. NABL accreditation is a useful marker, and home sample collection in major cities covers the blood tests that sometimes accompany the workup.

Frequently asked questions

References

Sources cited on this page. PubMed links open the original abstract.

1. Puhan MA, Gimeno-Santos E, Cates CJ, Troosters T. Pulmonary rehabilitation following exacerbations of chronic obstructive pulmonary disease. Cochrane Database Syst Rev. 2016;12(12):CD005305. PMID 27930803 · doi:10.1002/14651858.CD005305.pub4
2. Agustí A, Celli BR, Criner GJ, et al. Global Initiative for Chronic Obstructive Lung Disease 2023 Report: GOLD Executive Summary. Eur Respir J. 2023;61(4):2300239. PMID 36858443 · doi:10.1183/13993003.00239-2023
3. Falsey AR, Becker KL, Swinburne AJ, et al. Utility of serum procalcitonin values in patients with acute exacerbations of chronic obstructive pulmonary disease: a cautionary note. Int J Chron Obstruct Pulmon Dis. 2012;7:127–135. PMID 22399852 · doi:10.2147/COPD.S29149
4. MacLeod M, Papi A, Contoli M, et al. Chronic obstructive pulmonary disease exacerbation fundamentals: Diagnosis, treatment, prevention and disease impact. Respirology. 2021;26(6):532–551. PMID 33893708 · doi:10.1111/resp.14041