COPD: smoking cessation program improved lung function.

Clinical bottom line (level 1b)

  1. Smokers with mild COPD who received a smoking cessation program had an initial improvement in FEV 1 (on average 46 ml/min) compared with patients who received usual care. However there was no clear difference in mortality between the two groups.
  2. Smokers with mild COPD who received ipratropium and a smoking cessation program compared with usual care had an initial improvement in FEV 1 (on average 73 ml/min). However there was no clear effect on mortality.
  3. All groups had a decline in lung function after the first year. Only sustained quitters benefited.
Anthonisen et al: Journal of the American Medical Association 1994; 272: 1497-1505
Expires November 2003

The study

Single-blinded ?concealed randomised trial with intention-to-treat
Setting: 10 acute hospitals, USA and Canada

5887 patients (aged 35 to 60; mean 48, 63% male) smokers of at least 10 cigarettes per day with spirometric signs of early COPD (FEV1/FVC < 70%, and FEV1 55% to 90% predicted))

Excluded if
  • aged < 35, or > 60
  • on beta-blocker medication
  • regularly used physician-prescribed bronchodilators
  • evidence of other serious disease that might interfere with follow-up or lung function


    • Note:
  • Patients were stratified for centre before randomisation.


    • Control Group: (n = 1964, 1964 analysed): no intervention
    Experimental Group: (n = 1962, 1962 analysed): smoking intervention: 12-session smoking cessation program combining behaviour modification and use of nicotine gum, with continuing 5-year maintenance program to prevent relapse; and placebo
    Experimental Group: (n = 1961, 1961 analysed): smoking intervention; and ipratropium inhaler 2 puffs three times a day

    96% followed for 5 years

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    death: smoking cessation v. usual care 5 years 51
    (2.60%)    		 44
    (2.24%)    		 14%
    (-29% to 42%)    		 0.35%
    (-0.61% to 1.32%)    		 280
    (NNT = 76 to infinity;
    NNH = 170 to infinity)
    death: smoking cessation and ipratropium v. usual care 5 years 51
    (2.60%)    		 54
    (2.75%)    		 -6%
    (-55% to 27%)    		 -0.16%
    (-1.17% to 0.85%)    		 -640
    (NNT = 120 to infinity;
    NNH = 86 to infinity)

    Outcome Control Group
    (SD)    		 Experimental Group
    (SD)    		 Mean Difference
    (95% CI)
    decline in FEV 1 in first year: smoking cessation v. usual care 34.3
    (195)     		-11.2
    (190)     		-46
    (-58 to -33)
    decrease in FEV 1 in first years: smoking cessation and ipratropium v. usual care 34.3
    (195)     		-38.8
    (190)     		-73
    (-85 to -61)

    Comments

    1. After the first year, lung function declined at a similar rate in all three groups. The improvement was reversible, and is clinically barely significant.
    2. The study is too small to show any effect on mortality.
    3. No significant difference in the rate of hospitalisation was noted between the 3 groups (data not given).

    Citation

    1. Anthonisen NR, Connett JE, Kiley JP, et al: effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1 : the Lung Health Study. Journal of the American Medical Association 1994; 272: 1497-1505
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    Contributor: Bob Phillips and Chris Ball, November 1999
    Reviewer:

    Clinical Question.
    Patient smokers with mild COPD
    Intervention or Exposure smoking cessation program, ipratropium
    Comparison usual care
    Outcome death, decline in FEV 1