title: Eight-year follow-up of airway hyperresponsiveness in patients with primary Sjögren's syndrome.
abstract: OBJECTIVE
  To evaluate in a longitudinal study the influence of airway hyperresponsiveness (AHR) on lung function in patients with primary Sjögren's syndrome (pSS).
  
  
  METHODS
  Lung function was studied over an eight-year period in 15 patients who fulfilled the Copenhagen criteria for primary Sjögren's syndrome and who were covered in our earlier published study on AHR in patients with Sjögren's syndrome. Standard spirometry and measurements of lung volumes, diffusing capacity (DLCO), and AHR to methacholine were performed.
  
  
  RESULTS
  A significant decline over time was found in total lung capacity (TLC), vital capacity (VC), forced vital capacity (FVC), functional residual capacity (FRC), and expiratory midflows (FEF50). A sign of small airway obstruction (decrease in FEF50) at entry correlated with VC at follow-up (r = .8, P < .003), and the individual change in FEF50during the observation period correlated with the individual change in VC (r = .6, P < .05). Six patients had increased AHR, and three of them had decreased DLCO. Six of the patients progressively reduced DLCO over time, and five of them had spirometric signs of increased small airway obstruction.
  
  
  CONCLUSIONS
  During this eight-year follow-up we observed that one-third of the patients with pSS developed a significant reduction in lung function. Our findings suggest that small airways obstruction and AHR are associated with reduction of VC and development of impaired DLCO as a sign of interstitial lung disease in this group of patients.
authors.affiliation: a Department of Allergy , University Hospital , Reykjavik , Iceland.|b Department of Respiratory Medicine , University Hospital , Reykjavik , Iceland.
authors.forename: Dora
authors.initials: D
authors.lastname: Ludviksdottir
authors.affiliation: c Centre for Rheumatology Research, University Hospital , Reykjavik , Iceland.
authors.forename: Sigridur Th
authors.initials: ST
authors.lastname: Valtysdottir
authors.affiliation: d Department of Clinical Physiology , Akademiska Sjukhuset, Uppsala University Hospital , Uppsala , Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Hedenström
authors.affiliation: e Department of Medical Sciences , Akademiska Sjukhuset, Uppsala University Hospital , Uppsala , Sweden.
authors.forename: Roger
authors.initials: R
authors.lastname: Hällgren
authors.affiliation: c Centre for Rheumatology Research, University Hospital , Reykjavik , Iceland.|f Faculty of Medicine , University of Iceland , Reykjavik , Iceland.
authors.forename: Björn
authors.initials: B
authors.lastname: Gudbjörnsson
mesh_terms: D000368:Aged; D049628:Body Size; D001985:Bronchial Provocation Tests; D004058:Diffusion; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008168:Lung / Q000503:physiopathology*; D008297:Male; D016210:Methacholine Chloride / Q000737:chemistry; D008875:Middle Aged; D012129:Respiratory Function Tests; D012859:Sjogren's Syndrome / Q000175:diagnosis / Q000503:physiopathology*; D013147:Spirometry; D014797:Vital Capacity
chemical_list: D016210:Methacholine Chloride
keywords: Airway hyperresponsiveness; Sjögren’s syndrome; follow-up; lung function