Interstitial Lung Disease in Patients with Primary Sjögren’s Syndrome

Interstitial lung disease (ILD) involvement in primary Sjögren’s syndrome (pSS) is a common occurrence, presenting with vague initial symptoms that may include dry cough and dyspnea. Additionally, advanced age and Raynaud’s phenomenon

are risk factors for pulmonary interstitial complications in pSS. These were among study findings recently published in BMC Pulmonary Medicine.

Lung complications are the most common extraglandular manifestations of pSS, with ILD occurring most frequently. Early ILD detection is crucial in pSS patients, given that ILD could lead to life-threatening complications. However, controversy exists regarding whether or not all pSS patients should undergo a systematic search for lung involvement. Notably, few studies have investigated the risk factors for ILD detected by high-resolution computed tomography (HRCT) in pSS patients with or without respiratory symptoms.

In the current study, researchers in China sought to describe the baseline characteristics for ILD in pSS and investigate the risk factors by retrospectively analyzing data from 333 patients with newly diagnosed pSS. ILD involvement was defined as typical abnormalities on HRCT and/or pulmonary function tests.

In evaluating the study population, 66 patients (19.82%) were diagnosed with pSS-ILD, with ground glass opacities (87.88%) and septal/sub pleural lines (81.82%) being the most frequent. Based on HRCT, patients were divided into groups for nonspecific interstitial pneumonia (n=42), usual interstitial pneumonia (n=20), lymphocytic interstitial pneumonia (n=3), and cryptogenic organizing pneumonia (n=1).

The investigators found a strong association between the erythrocyte sedimentation rate (ESR)/C-reactive protein (CRP) and the HRCT-score. In addition, pulmonary function tests revealed impaired diffusion capacity for carbon monoxide and total lung capacity, and coexistence of small airway lesions in pSS-ILD. Based on logistic regression analysis, the researchers also determined that age, Raynaud’s phenomenon, lymphopenia, cough, and dyspnea were risk factors associated with pSS-ILD.

The researchers concluded, “Interstitial lung disease involvement in pSS is a common clinical occurrence,” although they noted that studies had shown it to be more common in Asia than in Europe. They added, “pSS patients with advanced age, dry cough and dyspnoea should be systematically evaluated for ILD involvement and managed according to their symptoms.”

Reference

Lin W, Xin Z, Zhang J, et al. Interstitial lung disease in Primary Sjögren’s syndrome. BMC Pulm Med. 2022;22(1):73. doi:10.1186/s12890-022-01868-5