Summary

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, fibrosing interstitial lung disease of unknown cause. It is characterised by the radiological and/or histological pattern of usual interstitial pneumonia (UIP). IPF predominantly affects older adults (over 60) and is more common in men. Symptoms include progressive exertional dyspnoea and dry cough. The prognosis is poor, with median survival of 3-5 years from diagnosis. Antifibrotic drugs (pirfenidone, nintedanib) slow decline but do not cure. Lung transplantation may be considered in suitable candidates.

Key Facts

• Definition: Chronic, progressive fibrosing ILD of unknown cause with UIP pattern
• Prevalence: ~3-20 per 100,000 (increasing with age)
• Peak Age: Over 60 years; rare below 50
• HRCT Pattern: UIP — peripheral, basal, honeycombing, traction bronchiectasis
• PFTs: Restrictive (low FVC, low TLC) with reduced DLCO
• Prognosis: Median survival 3-5 years without treatment

Clinical Pearls

"Velcro Crackles": Fine bibasal inspiratory crackles that sound like Velcro being pulled apart are characteristic of IPF. They're often present before radiological changes.

UIP Pattern is Key: Diagnostic HRCT features include honeycombing, traction bronchiectasis, and basal/peripheral distribution. If typical UIP pattern AND no identifiable cause → IPF diagnosis without biopsy.

Antifibrotics Slow, Don't Cure: Pirfenidone and nintedanib reduce FVC decline by ~50% but are not disease-modifying cures. Early referral and treatment initiation are important.

Why This Matters Clinically

IPF is a devastating diagnosis with limited treatment options. Early recognition (Velcro crackles, unexplained dyspnoea) and referral to specialist ILD services improves outcomes. Antifibrotics can slow progression, and supportive care (oxygen, pulmonary rehabilitation, palliative care) is essential.

Structured Approach

General:

• Respiratory rate, SpO2 at rest (6-minute walk test for exertional hypoxia)
• Clubbing

Respiratory Examination:

• Inspection: Clubbing, cyanosis, tachypnoea
• Auscultation: Bibasal fine inspiratory crackles ("Velcro")

Cardiovascular:

• Signs of pulmonary hypertension/right heart failure

Key Findings

Natural History

IPF is a progressive, fatal disease. Without treatment, median survival is 3-5 years. Disease trajectory is variable — some patients have slow decline, others rapid progression. Acute exacerbations carry >50% mortality.

Outcomes

Prognostic Factors (GAP Index)

Higher GAP score = worse prognosis

Key Guidelines

1. NICE NG163: Idiopathic Pulmonary Fibrosis (2017) — Diagnosis, referral, antifibrotic use.

2. ATS/ERS/JRS/ALAT Clinical Practice Guideline (2022) — Updated diagnostic criteria.

Landmark Trials

ASCEND Trial (2014) — Pirfenidone

• RCT in IPF
• Key finding: Reduced FVC decline by 50%; mortality benefit
• Clinical Impact: Led to wide pirfenidone adoption

INPULSIS Trials (2014) — Nintedanib

• Parallel RCTs in IPF
• Key finding: Reduced FVC decline by ~50%
• Clinical Impact: Established nintedanib as antifibrotic option

Evidence Strength

What is Idiopathic Pulmonary Fibrosis (IPF)?

Idiopathic Pulmonary Fibrosis (IPF) is a condition where the lungs become scarred (fibrosis) for unknown reasons (idiopathic). This scarring makes the lungs stiff and makes it harder to breathe. Unfortunately, IPF gradually gets worse over time.

Why does it matter?

IPF is a serious condition that affects quality of life and is life-limiting. However, treatments are available that can slow down the disease. Early diagnosis and treatment give the best chance of maintaining lung function for longer.

What are the symptoms?

• Gradually worsening shortness of breath (especially with activity)
• Dry cough
• Feeling tired
• Crackling sounds when breathing (your doctor may hear this)
• Clubbing (widening of fingertips) in some people

How is it treated?

1. Antifibrotic medication (pirfenidone or nintedanib): These tablets slow down the scarring in your lungs. They don't cure IPF but can help you keep your lung function longer.

2. Pulmonary rehabilitation: Exercise programmes to help you stay as active as possible.

3. Oxygen therapy: If your oxygen levels are low, you may need supplementary oxygen.

4. Lung transplant: For some patients, a lung transplant may be considered.

5. Palliative care: Specialists can help manage symptoms and support you and your family.

What to expect

• IPF is a progressive condition, meaning it gradually worsens over time
• Medications can slow this decline
• Regular clinic visits to monitor your lung function
• Breathlessness will gradually increase over months to years
• It's important to plan ahead and discuss your wishes with your family and healthcare team

When to seek help

Contact your team urgently if:

• You suddenly become much more breathless
• You develop fever or new symptoms
• Your oxygen levels drop significantly
• You have any concerns about your condition