Mixed airway and pulmonary parenchymal disease in patients with primary Sjögren's Syndrome - a six-year follow-up

OBJECTIVE: To assess pulmonary function and Chronic Obstructive Pulmonary Disease (COPD) development over time in patients with primary Sjögren's Syndrome (pSS) and the association between pulmonary function, radiographic findings, respiratory symptoms and clinical features of pSS, taking cigarette consumption into account.

METHODS: Forty patients with pSS (mean age 66 yrs, range 42-81 yrs, 39 women), previously participating in a cross-sectional study on pulmonary involvement in pSS, were re-assessed by pulmonary function tests after a mean follow-up time of six years. At follow-up, patients were also assessed by high-resolution computed tomography (HRCT) of the chest and for pSS disease activity, respiratory symptoms and cigarette consumption.

RESULTS: Patients with pSS showed significantly decreased percentages of predicted total lung capacity (TLC), residual volume (RV), RV/ TLC ratio and diffusing capacity of the lungs for carbon monoxide (DL,CO), and an increased percentage of predicted forced expiratory volume in one second/vital capacity (FEV1/VC) ratio from baseline to follow-up. The proportion of COPD did not change significantly from baseline to follow-up (38% vs. 40%). Radiographic signs of bronchial involvement and interstitial lung disease were found in 38% of the patients, respectively.

CONCLUSION: Both airway and pulmonary parenchymal disease were commonly found in pSS patients, with a co-existence of both an obstructive and a restrictive pulmonary function pattern, where the latter tended to deteriorate over time. COPD was still a common finding. Airway and pulmonary involvement may be underdiagnosed in pSS, why special attention to clinical assessment of pulmonary involvement in pSS patients is mandated.