title: Undiagnosed airflow limitation in patients at cardiovascular risk.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) and cardiovascular diseases (CVD) share risk factors and impair each other's prognosis.
  
  
  OBJECTIVE
  To assess the prevalence of airflow limitation (AL) compatible with COPD in a population at cardiovascular risk and to identify determinants of AL.
  
  
  METHODS
  All consecutive patients referred to the cardiovascular prevention unit of a university hospital in 2009 were studied in a cross-sectional analysis. Patients answered questionnaires on socioeconomic status, medical history and lifestyle, and underwent extensive physical examinations, biological measures and spirometry testing. AL was defined as FEV1/FVC<0.70, without any history of asthma. Determinants of AL were assessed using logistic regression.
  
  
  RESULTS
  The sample comprised 493 participants (mean age 57.4±11.1 years); 60% were men, 18% were current smokers, 42% were ex-smokers and 10% of patients had a history of CVD. Ten-year risk of coronary heart disease (CHD) according to the Framingham equation was intermediate (10-20%) for 25% of patients and high (>20%) for 10%. Prevalence of AL was 5.9% (95% confidence interval [CI] 4.0-8.3%) in the whole population and 4.3% (2.6-6.6%) among subjects in primary cardiovascular prevention. AL was independently associated with CVD (adjusted odds ratio 4.18, 95% CI 1.72-10.15; P=0.002) but not with Framingham CHD risk. More than 80% of patients screened with AL had not been diagnosed previously and more than one in two patients was asymptomatic.
  
  
  CONCLUSIONS
  Patients with CVD are at increased risk of AL and thus should benefit from AL screening as they are frequently asymptomatic.
authors.affiliation: UMR 1027 Inserm, Department of Epidemiology, Health Economics and Public Health, CHU de Toulouse, université de Toulouse, 31073 Toulouse cedex, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Bérard
authors.forename: Vanina
authors.initials: V
authors.lastname: Bongard
authors.forename: Nicolas
authors.initials: N
authors.lastname: Roche
authors.forename: Thierry
authors.initials: T
authors.lastname: Perez
authors.forename: Dany
authors.initials: D
authors.lastname: Brouquières
authors.forename: Dorota
authors.initials: D
authors.lastname: Taraszkiewicz
authors.forename: Stéphane
authors.initials: S
authors.lastname: Fievez
authors.forename: François
authors.initials: F
authors.lastname: Denis
authors.forename: Roger
authors.initials: R
authors.lastname: Escamilla
authors.forename: Jean
authors.initials: J
authors.lastname: Ferrières
mesh_terms: D000046:Academic Medical Centers; D000368:Aged; D058070:Asymptomatic Diseases; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000503:physiopathology; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D005602:France; D006801:Humans; D016015:Logistic Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D018570:Risk Assessment; D012307:Risk Factors; D013147:Spirometry; D011795:Surveys and Questionnaires; D014797:Vital Capacity