COPD: influenza vaccine reduces the number of exacerbations

Clinical bottom line (level 1a-)

  1. Patients with COPD who receive influenza vaccine compared with placebo have fewer exacerbations subsequently (on average 0.5 fewer).
  2. The effect on pneumonia and mortality is unclear.
Poole et al: Cochrane Library 2000; 2 : -
Expires October 2003

The study

Systematic review of all randomised controlled trials of
  • Patients: COPD
  • Intervention: live or inactivated influenza vaccine compared with placebo
  • Outcome: pneumonia, death

    Articles found in ?all languages using Cochrane Airways Group trials register derived from Medline, Embase, CINAHL, and hand-searches of respiratory journals and meeting abtracts, - (search terms: detailed in text ) and and searching bibliographies of retrieved studies for relevant articles. Drug companies and study authors were contacted to identify unpublished material.

    Selection criteria: see above
    Appraisal criteria: by 3 independent reviewers using the Jadad score
    Articles excluded if:
    • patients with asthma


    9 studies found; 4 specifically performed in 215 patients with COPD; the others involved elderly or chronically ill patients of whom some had COPD>

    The evidence

    Outcome Time to outcome CER OR
    (95% CI)    		 NN T
    (95% CI)
    COPD exacerbation 3 weeks 27/51
    (52.9%)    		 1.06
    (0.48 to 2.33)     		-69
    (NNT = 6 to infinity;
    NNH = 5 to infinity)

    • Weighted mean difference total exacerbations per patient: influenza vaccine v. placebo: - 0.45 (95% CI: -0.75 to -0.15)

    Comments

    1. The studies assessing hospitalisation and death were too small to exclude important clinical effects.

    Citation

    1. Poole PJ, Chacko E, Wood-Baker RWB: influenza vaccine for patients with chronic obstructive pulmonary disease. Cochrane Library 2000; 2 : -
    Search Terms: COPD in Cochrane Library
    Contributor: Chris Ball, October 2001
    Reviewer:

    Clinical Question.
    Patient COPD
    Intervention or Exposure influenza vaccine
    Comparison placebo
    Outcome pneumonia, death
    		•