title: Prevalence and risks of chronic airway obstruction: a population cohort study in taiwan.
abstract: BACKGROUND
  This study investigated the prevalence, incidence, and hospitalization for chronic airway obstruction (CAO) in a population cohort.
  
  
  METHODS
  Medical reimbursement claims from 1996 to 2002 based on a 1996 insured cohort of 167,372 persons from National Health Insurance, Taiwan, were used. We presented the chronological trends of CAO (International Classification of Diseases, Ninth Revision code 496) and the relationships between the CAO severity and age, sex, urbanization, and hospitalization and comorbidity for the population >/= 40 years old.
  
  
  RESULTS
  The overall average annual prevalence and incidence rates were 2.48/100 and 0.66/100, respectively, for the population, among 4,568 patients with CAO cared during the study period. For the population aged >/= 70 years, the prevalence rates had a peak of 8.83/100 in 1998 and afterward remained a plateau until 2002. The corresponding incidence decreased from 2.48/100 to 1.62/100, and the hospitalization rate for them had a peak of 2.22/100 in 1999. The multivariate logistic regression analysis showed that the risk of hospitalization for CAO was higher for patients with the comorbidity of renal failure, coronary artery disease, and pneumonia and influenza, but lower with skin and joint disorders.
  
  
  CONCLUSIONS
  The national insurance program promotes patient care and provides a proper pathway for surveillance and identification of CAO.
authors.affiliation: Institute of Environmental Health, National Taiwan University College of Public Health, Taipai.
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Wang
authors.affiliation: Institute of Environmental Health, National Taiwan University College of Public Health, Taipai.
authors.forename: Jia-Ming
authors.initials: JM
authors.lastname: Lin
authors.affiliation: Department of Public Health, Fu Jen Catholic University College of Medicine, Taipei Hsien.
authors.forename: Chung-Yi
authors.initials: CY
authors.lastname: Li
authors.affiliation: Department of Family Medicine, National Taiwan University Hospital, Taipai.
authors.forename: Long-Teng
authors.initials: LT
authors.lastname: Lee
authors.affiliation: Environmental and Occupational Medicine, National Taiwan University Medical Center, Taipai.
authors.forename: Yue-Liang
authors.initials: YL
authors.lastname: Guo
authors.affiliation: Institute of Environmental Health, China Medical University College of Public Health, Taichung, Taiwan. Electronic address: fcsung@mail.cmu.edu.tw.
authors.forename: Fung-Chang
authors.initials: FC
authors.lastname: Sung
mesh_terms: D000328:Adult; D000367:Age Factors; D000369:Aged, 80 and over; D015331:Cohort Studies; D015897:Comorbidity; D003431:Cross-Cultural Comparison; D003430:Cross-Sectional Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D012737:Sex Factors; D013624:Taiwan; D014507:Urbanization