by Dr. Valerie Milne

Interstitial lung disease (ILD) is a group of disorders that cause progressive scarring of lung tissue. ILDs can be caused by long-term exposure to hazardous materials, or by an auto-immune disease such as Rheumatoid Arthritis (RA).

ILDs occur in approximately 5 – 10 % of people with RA and about half of the people with RA have changes in the lungs that could indicate an undetectable ILD. While clinicians may be cautious about prescribing immunosuppressants with an ILD, studies have found methotrexate use is not associated with an increased risk of RA-associated IRD.

Symptoms of an ILD include a dry cough, and a gradual and increasing shortness of breath either after activity or when resting. Treatment of ILDs varies depending on the underlying cause and the amount of lung scarring that has occurred. Once scarring has occurred it usually cannot be reversed. Slowing lung damage and maintaining quality of life and increasing the chance of survival are the goals of treatment. Common ILD comorbidities include gastro-oesophageal reflux disease, sleep disorders, cardiovascular disease, diabetes, lung cancer, and pulmonary hypertension.

The risk of vaping leading to ILDs 

Not enough is known about the risk of vaping to understand the risk of the aerosol compounds in e-cigarettes that can lead to IRDs and that can cause acute, life-threatening lung injury. Vaping has been shown to have similar effects to smoking with airway irritation and inflammation and linked to increased symptoms for people with chronic airway diseases such as cystic fibrosis, asthma, and chronic obstructive pulmonary disease.

 Vaping particles are similar in size and concentration to tobacco smoke and are distributed in the lungs in a similar pattern. Some enzymes in the lung are elevated in vapers, also similar to elevation in cigarette smokers. An excess of these enzymes can trigger, or make worse, several chronic diseases including RA and cardiovascular disease. These factors indicate that vaping may be as harmful as smoking in terms of chronic lung disease as well as causing acute, life-threatening lung injury.

Educating people about the causes of ILDs and taking steps to reduce exposure to harmful substances for example, occupational exposure to coal dust or asbestos, and also substances that increase risk such as smoking and vaping, which have the potential to trigger ILDs or make existing ILDs worse.

While e-cigarettes are an important part of smoking cessation and tobacco harm reduction programmes, the health impact of vaping on people at risk of developing RA, or with a pre-existing risk of ILD due to RA remains unknown.

Should the cautionary principle be considered when advising people living with, or at risk of RA? If so, vaping should not be recommended as part of a smoking cessation plan. 

Note: A recent US cross-sectional study has also found that E-cigarette use may increase inflammatory arthritis risk.