title: Lung involvement in primary Sjögren's syndrome: Correlation between high-resolution computed tomography score and mortality.
abstract: BACKGROUND
  Lung involvement is one of the major systemic manifestations of primary Sjögren's syndrome (pSS). This study aims to demonstrate the correlation between high-resolution computed tomography (HRCT), pulmonary function test (PFT) results, and outcome in these patients.
  
  
  METHODS
  Forty-four pSS patients were enrolled and their PFT results and HRCT findings/scores were retrospectively investigated.
  
  
  RESULTS
  All patients had reduced carbon monoxide-diffusing capacity (DLCO; <75% of the predicted value); <60% of the predicted value of peak expiratory flow (PEF), of forced vital capacity (FVC), and of forced expiratory volume in the 1st second (FEV1) were noted in 15 (34.1%) patients, 13 (29.5%) patients, and 12 (27.3%) patients, respectively. HRCT scores had a negative correlation with DLCO (r = -0.376, p = 0.012), but not with other PFT results. Twelve patients (27.3%) expired during a mean follow-up of 3.7 years; 11 (91.7%) patients died of respiratory failure in the lung-involved patients, of which three were present with pneumonia. The expired patients had lower predicted values of FEV1 (63.1 ± 19.4% vs. 79.0 ± 22.7%, p = 0.017), FVC (58.7 ± 20.4% vs. 77.1 ± 17.5%, p = 0.005), and PEF (54.3 ± 20.5% vs. 72.0 ± 24.8%, p = 0.035), and higher HRCT scores (9.2 ± 5.7 vs. 5.2 ± 3.5, p = 0.033) than those patients who survived. Patients with FEV1, FVC, PEF < 60% of the predicted value, or high HRCT score (13-18) presented shorter median overall survival (p = 0.005, p < 0.001, p = 0.021, p < 0.001, respectively). Multivariate analysis adjusted for PFT results showed that HRCT ≥13 was an independent risk factor for mortality (p = 0.007).
  
  
  CONCLUSIONS
  The clinical outcome of pSS patients with lung involvement in Taiwan is not very favorable. Although HRCT score was poorly correlated with PFT, high HRCT score was significantly associated with higher mortality.
authors.affiliation: Department of Medicine, National Yang-Ming University Hospital, I-Lan, Taiwan, ROC; Division of Allergy, Immunology, Rheumatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Medicine, Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Chen
authors.affiliation: Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Hsiao-Ping
authors.initials: HP
authors.lastname: Chou
authors.affiliation: Division of Allergy, Immunology, Rheumatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Chien-Chih
authors.initials: CC
authors.lastname: Lai
authors.affiliation: Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Yu-Dong
authors.initials: YD
authors.lastname: Chen
authors.affiliation: Department of Medicine, Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.
authors.forename: Ming-Huang
authors.initials: MH
authors.lastname: Chen
authors.affiliation: Division of Allergy, Immunology, Rheumatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Medicine, Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.
authors.forename: Hsiao-Yi
authors.initials: HY
authors.lastname: Lin
authors.affiliation: Division of Allergy, Immunology, Rheumatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Medicine, Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC. Electronic address: dfhuang@vghtpe.gov.tw.
authors.forename: De-Feng
authors.initials: DF
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D012859:Sjogren's Syndrome / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed
keywords: HRCT score; lung involvement; mortality; primary Sjögren's syndrome; pulmonary function test