title: Prevalence of COPD in primary care clinics: correlation with non-respiratory diseases.
abstract: OBJECTIVE
  Various extrapulmonary effects and comorbidities have been noted to contribute to the burden of chronic obstructive pulmonary disease (COPD). However, the relationship between the prevalence of COPD and non-respiratory diseases has not been well investigated. The aim of the present study was to determine whether or not COPD is different among patients already suffering from other diseases.
  
  
  METHODS
  Spirometry was performed by patients aged >or=40 years old with non-respiratory diseases who visited primary care clinics. Four hundred eighty-one patients performed spirometry and 7 patients were excluded because of poor spirometry maneuvers, resulting in 474 patients that were eligible for the current study. In subjects showing abnormalities in their spirograms, precise diagnoses were made using a questionnaire and chest X-ray examination.
  
  
  RESULTS
  Among the 474 patients, airflow limitation (FEV(1)/FVC<70%) was observed in 53 patients (11.2%). Forty-nine patients (10.3%) were diagnosed as COPD and 4 patients (0.8%) as bronchial asthma. Among the various diseases, the prevalence of COPD was significantly higher only in the patients with liver diseases, which was 18.8% (12 of 64 patients). The odds ratio adjusted by both the amount of smoking and age was 2.66 (95%CI 1.06-6.63, p=0.037).
  
  
  CONCLUSIONS
  The prevalence of COPD was different according to the type of disease, and patients with liver diseases had a higher prevalence of COPD.
authors.affiliation: Third Department of Internal Medicine, Wakayama Medical University, Wakayama, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Minakata
authors.forename: Hisatoshi
authors.initials: H
authors.lastname: Sugiura
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yamagata
authors.forename: Satoru
authors.initials: S
authors.lastname: Yanagisawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ichikawa
authors.forename: Akira
authors.initials: A
authors.lastname: Koarai
authors.forename: Keiichirou
authors.initials: K
authors.lastname: Akamatsu
authors.forename: Tsunahiko
authors.initials: T
authors.lastname: Hirano
authors.forename: Kazuto
authors.initials: K
authors.lastname: Matsunaga
authors.forename: Masakazu
authors.initials: M
authors.lastname: Ichinose
mesh_terms: D000328:Adult; D000368:Aged; D000554:Ambulatory Care Facilities / Q000706:statistics & numerical data; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008107:Liver Diseases / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011320:Primary Health Care / Q000706:statistics & numerical data*; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D013147:Spirometry