What is the treatment approach for interstitial lung disease (ILD)?

Treatment Approach for Interstitial Lung Disease (ILD)

The treatment of interstitial lung disease should be tailored to the specific ILD subtype, with first-line therapy including antifibrotic medications for idiopathic pulmonary fibrosis and immunosuppressive agents for connective tissue disease-associated ILD. 1

Diagnostic Evaluation to Guide Treatment

Before initiating treatment, proper classification of ILD is essential:

• High-resolution CT scan (91% sensitive, 71% specific for diagnosing ILD subtypes) 1
• Pulmonary function tests (baseline FVC and DLCO)
• Assessment for underlying causes (connective tissue diseases, environmental exposures)
• Multidisciplinary discussion involving pulmonologists, rheumatologists, radiologists, and pathologists 2

Treatment Algorithm by ILD Subtype

1. Idiopathic Pulmonary Fibrosis (IPF)

• First-line treatment:

  • Antifibrotic therapy with nintedanib or pirfenidone 2, 1
  • These medications slow FVC decline by 44-57% 1
  • Pirfenidone: 2,403 mg/day (801 mg three times daily with food) 3
  • Nintedanib: 150 mg twice daily 4

• Not recommended for IPF:

  • Systemic corticosteroids (except for acute exacerbations) 2
  • "Triple therapy" (corticosteroids with azathioprine and N-acetylcysteine) - associated with increased mortality 2

2. Connective Tissue Disease-Associated ILD (CTD-ILD)

• First-line treatment options: 2

  • Mycophenolate mofetil
  • Azathioprine
  • Rituximab
  • Cyclophosphamide

• Disease-specific recommendations:

  • Systemic sclerosis-ILD (SSc-ILD):

    • Mycophenolate or tocilizumab
    • Nintedanib (conditionally recommended) 2
    • Avoid long-term glucocorticoids (strongly recommended against) 2

  • Rheumatoid arthritis-ILD (RA-ILD):

    • Mycophenolate, rituximab, or cyclophosphamide
    • Consider adding nintedanib or pirfenidone for progressive disease 2

  • Inflammatory myopathy-ILD (IIM-ILD):

    • Mycophenolate, rituximab, cyclophosphamide
    • Consider calcineurin inhibitors or JAK inhibitors 2

3. Rapidly Progressive ILD (RP-ILD)

For acute/severe presentation with rapid deterioration: 2

• First-line treatment:
  • IV pulse methylprednisolone followed by high-dose oral prednisone
  • Combined with one of: rituximab, cyclophosphamide, IVIG, mycophenolate

Management of Progressive Disease Despite Initial Treatment

For patients with continued decline on first-line therapy: 2

1. For all SARD-ILD progression:

   • Consider mycophenolate, rituximab, cyclophosphamide, or nintedanib

2. For RA-ILD progression:

   • Consider adding pirfenidone or tocilizumab

3. For IIM-ILD progression:

   • Consider calcineurin inhibitors, JAK inhibitors, or IVIG

4. For SSc-ILD progression:

   • Consider referral for stem cell transplantation or lung transplantation

Symptom Management

Cough Management in ILD

• Identify and treat comorbidities that may cause cough: 2

  • Gastroesophageal reflux disease (GERD)
  • Asthma/eosinophilic bronchitis
  • Upper airway cough syndrome

• For intractable cough: 2

  • Low-dose opiates may be considered for symptomatic relief, particularly in palliative care settings
  • Gabapentin or speech pathology-based cough suppression therapy

Dyspnea Management

• Supplemental oxygen for patients who desaturate below 88% on exertion 1
• Structured exercise therapy (improves symptoms and 6-minute walk test distance) 1

Monitoring and Follow-up

• Initial evaluation: PFTs within 3 months and HRCT within 6 months 2
• For mild ILD (FVC ≥70%, <20% fibrosis on HRCT): PFTs every 6 months for first 1-2 years 2
• For moderate-severe ILD: PFTs every 3-6 months 2
• A 5% decline in FVC over 12 months is associated with approximately 2-fold increase in mortality 1

Advanced Disease Management

• Consider lung transplantation evaluation for end-stage disease 1
  • Median survival after transplant: 5.2-6.7 years vs. <2 years without transplant 1
• For ILD with pulmonary hypertension (occurs in up to 85% of end-stage fibrotic ILD): 1, 5
  • Consider inhaled treprostinil (improves walking distance and respiratory symptoms)

Important Pitfalls to Avoid

1. Delayed diagnosis and treatment - Early intervention is critical for improved outcomes 6
2. Inappropriate use of corticosteroids in IPF - Associated with increased mortality when used in "triple therapy" 2
3. Failure to recognize and manage comorbidities - GERD, pulmonary hypertension, and sleep apnea can worsen outcomes
4. Overlooking progressive disease - Regular monitoring with PFTs and imaging is essential to identify progression early 7
5. Neglecting supportive care - Exercise, oxygen therapy, and pulmonary rehabilitation are important components of management