title: Pulmonary involvement in rheumatoid arthritis: evaluation by radiography and spirometry.
abstract: OBJECTIVE
  To determine whether simple diagnostic methods can yield relevant disease information in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  Patients with RA were randomly selected for inclusion in a cross-sectional study involving clinical evaluation of pulmonary function, including pulse oximetry (determination of SpO2, at rest), chest X-ray, and spirometry.
  
  
  RESULTS
  A total of 246 RA patients underwent complete assessments. Half of the patients in our sample reported a history of smoking. Spirometry was abnormal in 30% of the patients; the chest X-ray was abnormal in 45%; and the SpO2 was abnormal in 13%. Normal chest X-ray, spirometry, and SpO2 were observed simultaneously in only 41% of the RA patients. A history of smoking was associated with abnormal spirometry findings, including evidence of obstructive or restrictive lung disease, and with abnormal chest X-ray findings, as well as with an interstitial pattern on the chest X-ray. Comparing the patients in whom all test results were normal (n = 101) with those in whom abnormal test results were obtained (n = 145), we found a statistically significant difference between the two groups, in terms of age and smoking status. Notably, there were signs of airway disease in nearly half of the patients with minimal or no history of tobacco smoke exposure.
  
  
  CONCLUSIONS
  Pulmonary involvement in RA can be identified through the use of a combination of diagnostic methods that are simple, safe, and inexpensive. Our results lead us to suggest that RA patients with signs of lung involvement should be screened for lung abnormalities, even if presenting with no respiratory symptoms.
authors.affiliation: Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Alexandre Melo
authors.initials: AM
authors.lastname: Kawassaki
authors.affiliation: Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Daniel Antunes Silva
authors.initials: DA
authors.lastname: Pereira
authors.affiliation: Faculdade de Medicina, Hospital das Clínicas, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Fernando Uliana
authors.initials: FU
authors.lastname: Kay
authors.affiliation: Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Ieda Maria Magalhães
authors.initials: IM
authors.lastname: Laurindo
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Carlos Roberto Ribeiro
authors.initials: CR
authors.lastname: Carvalho
authors.affiliation: Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, BR.
authors.forename: Ronaldo Adib
authors.initials: RA
authors.lastname: Kairalla
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications*; D003430:Cross-Sectional Studies; D004417:Dyspnea / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D010092:Oximetry; D015995:Prevalence; D011859:Radiography; D012129:Respiratory Function Tests / Q000379:methods; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology; D013147:Spirometry