COPD: exacerbation: mucolytics have no clear effect

Clinical bottom line (level 2a-)

  1. Patients with an exacerbation of COPD who take mucolytics compared with placebo are not clearly more likely to have an improvement in spirometry or produce less sputum.
McCrory et al: AHRQ Publication No. 01-E003. Rockville (MD): 2001; : -
Expires October 2005

The study

Systematic review of randomised controlled trials or prospective controlled studies of
  • Patients: acute exacerbation of COPD (based on clinical diagnosis, spirometry, or known or suspected history, with increasing dyspnea, sputum quantity or purulence, or acute respiratory failure).
  • Intervention: mucolytics compared with placebo
  • Outcome: improvement in spirometry or symptoms

    Articles found in English using Medline, Embase, Cochrane Controlled Trials Register, 1966 to June 1999 (search terms: 'chronic obstructive pulmonary disease' and 'acute exacerbation', index terms and specific terms relating to interventions and methodology: detailed in text )

    Selection criteria: see above
    Appraisal criteria: detailed in text - studies assessed by 2 independent reviewers
    Articles excluded if:
    • studies of patients with: chronic MV needs, tracheostomies, asthma, bronchiolitis obliterans with organizing pneumonia, bronchiolitis obliterans, bronchiectasis, cystic fibrosis, and immunocompromised status (had known lung cancer, HIV/AIDS, or tuberculosis; or were on chemotherapy or radiation therapy for any cause).
    • Nonsystematic reviews (traditional narrative reviews)
    • Studies relating to the use of sputum culture


    6 RCTs found involving 198 patients.
    • No meta-analysis of the data was possible due to the heterogenous nature of the studies.

    The evidence

    • None of these trials reported statistically significant differences in mean FEV1 between treatments.
    • Of the five trials measuring symptom improvement, two reported a statistically significant difference (p < 0.01) favoring the mucolytic drug over control

    Comments

    1. By only selecting English language articles, important studies in other languages may have been missed.

    Citation

    1. McCrory DC, Brown C, Gray RN, et al: Management of Acute Exacerbations of COPD. Evidence Report/Technology Assessment No. 19 (Contract 290-97-0014 to the Duke University Evidence-based Practice Center). Agency for Healthcare Research and Quality. AHRQ Publication No. 01-E003. Rockville (MD): 2001; : -
    Search Terms: found on AHRQ website
    Contributor: Chris Ball, October 2001
    Reviewer:

    Clinical Question.
    Patient exacerbations of COPD
    Intervention or Exposure mucolytics: domiodol, bromhexine, ambroxol, S-carboxymethylcysteine, erdostein, potassium iodide
    Comparison placebo, chloramphenicol, or another mucolytic
    Outcome spirometry, symptom scores, sputum
    		•