title: [Long-term follow-up study of moderate chronic obstructive pulmonary disease in elderly patients].
abstract: OBJECTIVE
  To investigate the prognosis of moderate chronic obstructive pulmonary disease (COPD) in the elderly patients, and to evaluate the factors for long term survival.
  
  
  METHODS
  From May 1993, a prospective cohort study was carried out, in which 191 elderly patients with moderate COPD were recruited in Shougang communities, Shijingshan District, Beijing. The general health state, arterial blood gas, pulmonary function test, electrocardiograph, chest X-ray and 6-minute-walk test (6MWT) were recorded. The patients were followed for 12 years. Univariate analysis of survival rate was performed by Kaplan-Meier method. The significance test was done by Log-rank method, and the baseline factors were analyzed using the COX regression model multiplicity.
  
  
  RESULTS
  During the 12 years of follow-up, 10 patients were lost because of migration. Twenty-six patients died of non-COPD diseases, while 52 died of COPD. The survival rate was 81.7% (156/191) in 5 years, and 56.9% (103/181) in 12 years. The result with COX multiplicity showed that the important factors for prognosis of the patients were body mass index [BMI, relative risk (RR) = 0.916, 95% confidence intervals (95% CI) = 0.841 - 0.996], forced expired volume in one second (FEV(1), RR = 0.999, 95% CI = 0.998 - 1.000), arterial partial pressure of oxygen (PaO(2), RR = 0.929, 95% CI = 0.892 - 0.967), 6MWT (RR = 0.997, 95% CI = 0.995 - 1.000) and P pulmonale of ECG (RR = 4.081, 95% CI = 1.567 - 10.624).
  
  
  CONCLUSIONS
  The important factors for prognosis of moderate COPD in elderly patients included BMI, FEV(1), PaO(2), 6MWT and P pulmonale in ECG.
authors.affiliation: Department of Respiratory Medicine, Peking University Shougang Hospital, Beijing 100041, China.
authors.forename: Ping-chao
authors.initials: PC
authors.lastname: Xiang
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yao
authors.forename: Xian-sheng
authors.initials: XS
authors.lastname: Cheng
authors.forename: Er-ming
authors.initials: EM
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.forename: Li-ping
authors.initials: LP
authors.lastname: Song
authors.forename: Li-xin
authors.initials: LX
authors.lastname: Ju
authors.forename: Yan
authors.initials: Y
authors.lastname: Ding
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000401:mortality*; D012129:Respiratory Function Tests; D015996:Survival Rate