Exercise training appears to be effective in the care of patients with multiple types of interstitial lung diseases, achieving clinically meaningful benefits in those with asbestosis and idiopathic pulmonary fibrosis.


 

Evidence supporting the use of exercise training for patients with interstitial lung disease (ILD) has rapidly expanded in recent years, providing promising results that include improved exercise tolerance, symptoms, and quality of life. However, data are lacking on the effectiveness of exercise training across the entire range of diverse ILDs. “As such, recommendations for exercise training in international clinical guidelines remain weak for this patient group, and uptake into routine clinical practice has not been widespread,” explains Leona Dowman. “In order for exercise training for ILD to be widely adopted in clinical practice and to be strongly recommended as an effective treatment, more robust information regarding its role across the entire disease spectrum is required.”

 

Establishing Benefits

For a study published in Thorax, Dowman and colleagues sought to establish whether the benefits of exercise training vary by ILD type and severity, as well as whether an optimal time exists for exercise training in order to maximize benefits. “Exercise training is one of the few treatments to induce positive changes in exercise tolerance and symptoms in ILD,” says Dowman. “However, there appears to be marked variability in response. Preliminary evidence suggests that patients with idiopathic pulmonary fibrosis (IPF)—the most severe of ILDs—may improve less than those with other ILDs. In addition, the timing of exercise training may be critical in IPF patients. Greater improvements tend to occur in those with milder IPF disease, whereas those with other ILDs appear to achieve benefits from exercise training regardless of disease severity.”

Across multiple sites, the study team recruited patients with a documented diagnosis of ILD and randomized them to 8 weeks of supervised exercise training or their standard medical care. Exercise training was conducted within standard pulmonary rehabilitation programs of the physiotherapy departments of each hospital. Measures of functional capacity, dyspnea, and quality of life were obtained at baseline, upon completion of exercise training, and 6 months after completion by an independent, blinded clinician.  Respiratory function testing and a transthoracic echocardiogram were performed on each participant to quantify disease severity and identify the presence of pulmonary hypertension, a common complication of ILD.

The researchers found that exercise training significantly increased both 6-minute walking distance and health-related quality of life in patients with ILD. “While the exercise response in ILD was similar across disease subtypes, the largest changes were seen in those with asbestosis, followed by those with IPF,” says Dowman (Figure), “but both groups obtained clinically meaningful improvements, suggesting that exercise training is equally effective for IPF and asbestosis. Patients with connective tissue disease-related ILD showed less improvement and may require a different exercise training approach than those employed in typical pulmonary rehabilitation programs that considers the systemic manifestations of their disease.”

Dowman notes that disease severity did not alter patients’ ability to follow exercise training. “However, those with milder disease had more sustained benefits of exercise training, suggesting that undertaking supervised exercise training earlier on in the disease may assist in preserving benefits,” she adds.

 

Important Implications

The study findings suggest that exercise training is an effective and key intervention across the range of ILDs, according to Dowman. “Improvements in exercise tolerance, quality of life, and symptoms are comparable to those in patients with COPD, a population for whom exercise training is a cornerstone of clinical management,” she adds. “This, therefore, provides strong evidence for exercise training as a standard of care in all patients with ILD, regardless of etiology or severity. Clinicians should strongly encourage patients with ILD to attend pulmonary rehabilitation. An early referral, where possible, is recommended to promote longer-lasting effects.”

References

Dowman L, McDonald C, Hill C, et al. The evidence of benefits of exercise training in interstitial lung disease: a randomised controlled trial. Thorax. 2017;72:610-619. Available at http://thorax.bmj.com/content/72/7/610.

Holland A, Hill C. Physical training for interstitial lung disease. Cochrane Database Syst Rev. 2008, October 8. [ePub]. Available at http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD006322.pub2/abstract.

Dowman L, Hill C, Holland A. Pulmonary rehabilitation for interstitial lung disease.  Cochrane Database Syst Rev. 2014, October 6. [ePub]. Available at http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD006322.pub3/full.

Demedts M, Wells A, Anto J, et al. Interstitial lung disease. an epidemiological overview. Eur Respir J. 2001;18:2s-16s.