Background/Purpose:   To evaluate the amount and impact of respiratory symptoms in patients with primary Sjögren’s syndrome (pSS) and to assess if such symptoms are related to concomitant COPD or ILD.

Methods: Fifty-one consecutive outpatients diagnosed with pSS (median age 61, range 29-82 years, 49 females) and 80 population based controls (median age 61, range 31-80 years, 43 females), denying having been diagnosed with a rheumatological disease, asthma or COPD as well as using bronchodilators and/or inhalation steroids the last 6 months, were included in the study. The pSS patients were evaluated by pulmonary function test as well as CT scans of the lungs. 21 pSS patients fulfilled GOLD criteria for COPD and 9 patients showed radiologic signs of ILD. All subjects also completed a questionnaire on smoking habits from which tobacco consumption could be calculated as well as the St George’s Respiratory Questionnaire (SGRQ) on respiratory symptoms. The controls were then stratified into females and males and a linear regression analysis was performed in which age, body-mass index (BMI) and pack-years were added as co-variates to calculate gender, age, BMI and pack-year standardised values for the SGRQ subscores and total score. From the equations of these analyses, expected values for the SGRQ subscores and total score in the pSS patients were calculated. The expected SGRQ-scores were then compared with the actual SGRQ-scores found in the pSS patients. To compare the SGRQ scores in pSS patients with vs. without COPD we calculated the deviation of SGRQ scores from expected values in each pSS patient and compared the groups. The same calculation was performed to compare pSS patients with and without radiologic signs of ILD.

Results:   pSS patients had significantly increased SGRQ symptom (25.2 (6.6; 40.5) vs. 2.3 (1.4; 3.8); p<0.001), SGRQ activity (39.5 (12.2; 53.6) vs. 12.5 (8.2; 17.5); p<0.001), SGRQ impact (9.9 (0; 23.3) vs. 0.7 (0.5; 1.1); p<0.001) as well as SGRQ total scores (17.4 (7.4; 34.5) vs. 4.6 (3.3; 6.3); p<0.001) in comparison to expected scores based on the results of the population based controls. However, there was no significant difference in the deviation of SGRQ symptom, SGRQ activity, SGRQ impact or SGRQ total scores from expected values in pSS patients with and without COPD or ILD respectively.

Conclusion:   In conclusion we showed that respiratory symptoms were more common amongst pSS patients than in the normal population. Concomitant COPD or ILD did not seem to significantly contribute to these, suggesting that other factors are more important in eliciting such symptoms in pSS patients, of which airway sicca is probably the most important. Since pulmonary involvement in pSS is associated with an increased mortality and respiratory symptoms is a poor marker for pulmonary involvement, we suggest that at least PFT should be performed liberally in all pSS patients regardless of symptoms to enable early detection of pulmonary involvement in these patients.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/respiratory-symptoms-in-patients-with-primary-sjogrens-syndrome-a-case-control-study/