COPD: women were at greater risk

Clinical bottom line (level 1b)

  1. One in sixty people were admitted to hospital with COPD.
  2. Patients were more likely to be admitted to hospital with COPD if they
    • were female
    • inhaled cigarettes
Prescott et al: European Respiratory Journal 1997; 10: 822-827
Expires November 2003

The study

Prospective cohort study with objective outcomes, adjusted for confounding factors, not validated in an independent set of patients.

Setting: 2 regions, Denmark

13897 patients (aged mean 45 years, 53% female) from a population study (stratified for age)

Excluded if
  • aged < 20
  • born before 1920



    • Factors studied:
  • age, sex, smoking history (tobacco exposure, pack-years), cohabitation, length of education
  • female
  • years spent inhaling cigarettes (per 10 years)




    • Cox proportional hazards model performed to adjust for confounding factors.

    ?100% followed for 7 to 16 years
    Outcomes studied:
  • admitted to hospital with COPD identified using a National Hospital Discharge Register

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)    		 NNF
    (95% CI)
    admitted to hospital with COPD 7 to 16 years 241/13897 1.7%
    (1.5% to 2.0%)    		 58
    (51 to 66)

    prognostic factor for
    admitted to hospital with COPD     		time to outcome adjusted RR
    (95% CI)    		 NNF+
    (95% CI)
    female 7 to 16 years 3.6
    (1.4 to 9.0)     		22
    (7 to 140)
    years spent inhaling cigarettes (per 10 years) 7 to 16 years 1.6
    (1.0 to 2.7)     		96
    (34 to infinifty)

    Citation

    1. Prescott E, Bjerg AM, Andersen PK, et al: gender difference in smoking effects on lung function and risk of hospitalization for COPD: results from a Danish longitudinal population study. European Respiratory Journal 1997; 10: 822-827
    Search Terms: ?
    Contributor: Chris Ball and Clare Wotton, November 1999
    Reviewer: Paul Sullivan

    Clinical Question.
    Patient well
    Intervention or Exposure smoking, sex
    Outcome admission to hospital with COPD