Monday, 24 Feb 2020

You are here

Link Between Obstructive Lung Disease and Developing RA?

We all know that the microbiome in the gut may be very important for multiple immune diseases. However, new findings from the ACR, 2019 in Atlanta reinforce how important the interface is between the lungs and developing rheumatoid arthritis.

It has been known that cyclical citrullinated proteins that are immunogenic (causing ACPAs) may develop in the lungs before RA. We also know that restrictive lung disease (interstitial lung disease, ILD) is increased in RA. Two studies showed that before the onset of RA, obstructive lung disease - COPD and, less so, asthma new onset - increased.

The Nurses Health Study demonstrated that new RA onset onset had increased COPD as a new diagnosis first with almost a two-fold risk with matching people without developing RA and adjusting for smoking.  The risk was higher in seropositive patients compared to seronegative. The onset of asthma was also increased but with less frequency than new onset COPD which makes sense due to the age of the cohort that was followed (1). Another study of patients at risk for RA (pre-RA, +ACPA) had an increased risk of obstructive lung disease (COPD and asthma) especially in the pre-RA period; more than after RA was diagnosed (3). A final tidbit, in areas of high air pollution, there was an increase in ACPA positivity (3). This doesn’t mean a cause and effect but interesting as air pollution of course can inflame lungs.

What does this mean clinically? We need to be aware that in RA there is not only an increase in ILD, but also COPD which may certainly predate RA. Inflammation of the lungs causes protiens to citrullinate (likely) and increases antibody production. Of course, smoking is more common in RA but other studies have adjusted for presumed smoking rates and still saw more hospitalizations for COPD prior to RA onset. 


  1. Ford J, et al. ACR 2019, Atlanta, #186 
  2. Zaccardelli A, et al. ACR 2019, Atlanta, #841
  3. Zhao N, et al. ACR 2019, Atlanta, #L02
  4. Mcguire K,et al. Arthritis Care Res. 2019;71:602-610. doi: 10.1002/acr.23410



The author has no conflicts of interest to disclose related to this subject

Add new comment

More Like This

Seronegativity on the Rise in RA

Although the overall incidence rates of rheumatoid arthritis (RA) have remained stable over recent decades, there has been a significant increase in seronegative cases, a retrospective study showed.

Alcohols Net Zero Effect in Rheumatoid Arthritis

A report from The National Databank for Rheumatic Disease addressed the impact of alcohol on disease activity and mortality in rheumatoid arthritis (RA) and found that alcohol use was not associated with changes in disease activity or mortality, after addressing confounders. 

DMARD Inertia by Registry Rheumatologists

A registry study of metric use (primarily RAPID3 and CDAI) in the treatment of rheumatoid arthritis (RA) patients shows that, even in the face of moderate or high disease activity, treatment changes by rheumatologists were relatively low (35.6–54.6%).

Bariatric Weight Loss Fails to Alter RA Risk

Obesity has been shown to be a risk factor for the onset of rheumatoid arthritis (RA) and also shown to affect outcomes by impairing responses to many DMARD therapies. A Swiss study of RA patients undergoing bariatric surgery failed to show that bariatric surgery and weight loss had any effect on the incidence of RA.

Limited Advantage to Very Early vs. Delayed Etanercept in RA

The VEDERA study sought to confirm whether the very early introduction of first-line etanercept+methotrexate (ETN+MTX) was superior to treat-to-target MTX (MTX-TT) in patients with early RA.