title: Undifferentiated connective tissue disease-associated interstitial lung disease: changes in lung function.
abstract: Undifferentiated connective tissue disease (UCTD) is a distinct clinical entity that may be accompanied by interstitial lung disease (ILD). The natural history of UCTD-ILD is unknown. We hypothesized that patients with UCTD-ILD would be more likely to have improvement in lung function than those with idiopathic pulmonary fibrosis (IPF) during longitudinal follow-up. We identified subjects enrolled in the UCSF ILD cohort study with a diagnosis of IPF or UCTD. The primary outcome compared the presence or absence of a > or = 5% increase in percent predicted forced vital capacity (FVC) in IPF and UCTD. Regression models were used to account for potential confounding variables. Ninety subjects were identified; 59 subjects (30 IPF, 29 UCTD) had longitudinal pulmonary function data for inclusion in the analysis. After accounting for baseline pulmonary function tests, treatment, and duration between studies, UCTD was associated with substantial improvement in FVC (odds ratio = 8.23, 95% confidence interval, 1.27-53.2; p = 0.03) during follow-up (median, 8 months) compared with IPF. Patients with UCTD-ILD are more likely to have improved pulmonary function during follow-up than those with IPF. These findings demonstrate the clinical importance of identifying UCTD in patients presenting with an "idiopathic" interstitial pneumonia.
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267-0564, USA. brent.kinder@uc.edu
authors.forename: Brent W
authors.initials: BW
authors.lastname: Kinder
authors.forename: Cyrus
authors.initials: C
authors.lastname: Shariat
authors.forename: Harold R
authors.initials: HR
authors.lastname: Collard
authors.forename: Laura L
authors.initials: LL
authors.lastname: Koth
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Wolters
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Golden
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: Panos
authors.forename: Talmadge E
authors.initials: TE
authors.lastname: King
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003240:Connective Tissue Diseases / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D016015:Logistic Models; D008137:Longitudinal Studies; D008168:Lung / Q000503:physiopathology*; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011653:Pulmonary Diffusing Capacity; D020127:Recovery of Function; D012189:Retrospective Studies; D018570:Risk Assessment; D013997:Time Factors; D016896:Treatment Outcome; D014797:Vital Capacity