From the Guidelines
Pulmonary function tests (PFTs) should be repeated every 3 to 6 months for the first year in patients with interstitial lung disease (ILD) associated with systemic autoimmune rheumatic diseases, and then less frequently once stable, as suggested by the 2023 American College of Rheumatology (ACR)/American College of Chest Physicians (CHEST) guideline 1. The frequency of PFTs depends on the patient's condition and clinical circumstances. For patients with stable respiratory conditions, PFTs are typically repeated every 1-2 years. However, patients with progressive diseases like ILD may need testing every 6-12 months to monitor disease progression and treatment response.
- The 2023 ACR/CHEST guideline suggests that PFTs should be performed every 3-6 months for the first year in patients with IIM-ILD and SSc-ILD, and then less frequently once stable 1.
- For patients with RA-ILD, SjD-ILD, and MCTD-ILD, PFTs should be performed every 3-12 months for the first year, and then less frequently once stable 1.
- More frequent monitoring is needed early in the course of disease and in patients with active or progressive disease, and then every 6-12 months after the first year if the disease is stable 1.
- The guideline also suggests that ambulatory desaturation testing should be performed every 3-12 months in patients with SARD-ILD 1. The timing of PFTs should be individualized based on disease stability, symptoms, and treatment changes. More frequent testing provides better tracking of lung function trends but must be balanced against cost and patient burden. The value of PFTs comes from comparing results over time to detect meaningful changes in lung function that might warrant treatment modifications, as noted in the 2023 ACR/CHEST guideline 1.
From the Research
Pulmonary Function Tests (PFTs) Frequency
The frequency of repeating pulmonary function tests (PFTs) is not directly addressed in the provided studies. However, the studies discuss the importance of monitoring lung function in patients with chronic obstructive pulmonary disease (COPD) and asthma.
- The studies suggest that PFTs, including forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), and peak expiratory flow (PEF), should be measured regularly to assess disease progression and response to treatment 2, 3, 4.
- The frequency of PFTs may depend on the individual patient's condition and treatment plan. For example, patients with COPD may require more frequent PFTs to monitor disease progression and adjust treatment 5, 2.
- In patients with asthma, PFTs may be performed regularly to assess asthma control and adjust treatment 4, 6.
- The studies do not provide a specific recommendation for the frequency of repeating PFTs, but suggest that regular monitoring of lung function is important for effective disease management 5, 2, 3, 4, 6.