Nearly 65% of Patients with RA, PsA Had Asymptomatic Pulmonary Involvement

A recent study showed the prevalence of asymptomatic pulmonary involvement in patients with newly diagnosed rheumatoid arthritis (RA) and psoriatic arthritis (PsA).1 The research also revealed a lack of correlation between pulmonary function, disease function, and medication during the disease progression.

“The lack of correlation…suggests that reducing arthritic disease activity does not necessarily mitigate the risk or severity of pulmonary involvement,” wrote investigators, led by Lone Winter and Simon M. Petzinna, both from the department of rheumatology and clinical immunology at the Clinic of Internal Medicine III, University Hospital Bonn in Germany.

Pulmonary involvement in arthritis puts people at risk of morbidity and mortality. In RA, pulmonary involvement is one of the leading causes of death and is linked to a 3-fold increase in mortality rates.2 RA can be associated with interstitial lung diseases, such as pulmonary fibrosis and restrictive lung disease.3

Winter, Petzinna, and colleagues sought to longitudinally assess pulmonary involvement in patients with newly diagnosed RA and PsA over 12 months.1 They aimed to identify biomarkers and create a diagnostic algorithm for monitoring pulmonary changes.

The study included 76 patients aged > 18 years 26 with RA, 24 with PsA, and 26 controls—from University Hospital Bonn who underwent clinical and laboratory assessments, pulmonary function tests, and chest radiography at 3-month intervals for 1 year. The sample included 27 males among patients with arthritis and 12 males among controls. A board-certified rheumatologist diagnosed patients using ACR/European League Against Rheumatism criteria 2010 for RA and CASPAR criteria for PsA.

At baseline, 37% of patients with arthritis (50% with RA; 22.7% with PsA) presented with radiographic pulmonary involvement; 64.7% had asymptomatic pulmonary involvement. 36% of the arthritis group (42.3% RA, 29.2% PsA) experienced respiratory symptoms, compared with 11.5% of the control group (P = .031).

Investigators observed reduced pathological breathing width in 69.2% of participants with RA, 58.3% with PsA, and 23.1% of controls (P < .001). Thoracic excursion (P < .642) and lung auscultation (P = .544) demonstrated no differences between patients with arthritis and controls.

The mean DAS28CRP was 4.0 (95% confidence interval [CI], 3.5–4.4) in patients with RA and 3.3 (95% CI: 2.9–3.8) in patients with PsA; patients with radiographic pulmonary involvement often had greater DAS28CRP (median 3.9; range 2.8) than those without pulmonary involvement (median 3.1, range 4.9).

Additionally, increased RF levels (> 14 IU/ml) were present in 33.3% of patients with arthritis (P = .026) and more common in participants with pulmonary involvement as seen on the chest radiography (P = .024).

During the 12-month follow-up, pulmonary function tests and physical examination findings remained stable. Mean CRP levels significantly reduced in patients with RA (from 23.5 mg/L; 95% CI, 9.9 – 37.1 to 2.7 mg/L; 95% CI, 1.0 – 4.3) and PsA (from 13.3 mg/L; 95% CI, 5.7 – 20.9 to 8.1 mg/L; 95% CI, 0.1 – 16.2) (P < .001). The study also showed a reduction in the mean DAS28CP among patients with RA (4.0; 95% CI, 3.5–4.4 to 1.4; 95% CI: 1.0 – 1.8) and PsA (3.3; 95% CI, 2.9–3.8 to 1.6; 95% CI, 1.25–2.0) during the 12 months.

Investigators found significant reductions in disease activity scores and symptom improvements after a 6-minute walk but observed no significant differences regarding pulmonary involvement.

The team did not observe a link between pulmonary function tests and chest radiography. They also did not observe associations between pulmonary function tests, disease activity, or rheumatological medications during the 12 months.

Investigators concluded that further research needs to evaluate the long-term progression of pulmonary involvement and the impact of beginning treatment on RA and PsA. They also added how chest radiography and pulmonary function tests, although practical, may not be the best at detecting early pulmonary abnormalities, and more advanced imaging techniques, such as HRCT, could be better for detection.

“The fact that most patients with pulmonary involvement were asymptomatic necessitates a reevaluation of existing screening protocols to prevent delayed diagnosis and treatment, which could negatively impact patient outcomes,” investigators wrote. “Our study indicates that clinicians should be alert to indicators like high disease activity as measured by DAS28CRP, increased age, and elevated rheumatoid factor levels, even in the absence of symptoms like dyspnea and cough.”

References

1. Winter L, Petzinna SM, Skowasch D, Pizarro C, Weber M, Kütting D, Behning C, Bauer CJ, Schäfer VS. Pulmonary involvement in newly diagnosed and untreated rheumatoid arthritis and psoriatic arthritis: a prospective longitudinal study. Rheumatol Int. 2024 Dec 18;45(1):3. doi: 10.1007/s00296-024-05751-w. PMID: 39692860; PMCID: PMC11655587.
2. Kunzmann, K. COPD Linked to Three-Fold Greater Mortality Risk in Severe COVID-19 Patients. HCPLive. October 18, 2020. https://www.hcplive.com/view/copd-three-fold-greater-mortality-risk-severe-covid-19-patients. Accessed January 2, 2025.
3. Pine, L. Joshua Solomon, MD: Safety and Efficacy of Pirfenidone in Patients with Rheumatoid Arthritis Interstitial Lung Disease. HCPLive. November 3, 2021. https://www.hcplive.com/view/joshua-solomon-md-safety-and-efficacy-of-pirfenidone-in-patients-with-rheumatoid-arthritis-interstitial-lung-disease. Accessed January 2, 2025.