title: A randomised controlled trial of four weeks versus seven weeks of pulmonary rehabilitation in chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Pulmonary rehabilitation programmes have been shown to improve both exercise tolerance and health status in patients with chronic obstructive pulmonary disease (COPD). The optimal duration for a pulmonary rehabilitation programme is, however, unknown. To assess whether the current pulmonary rehabilitation programme could be shortened a randomised controlled trial was conducted in 44 patients with COPD who were allocated to either a seven week or a four week course.
  
  
  METHODS
  Patients were randomised to either our standard seven week twice weekly outpatient based programme or a comparable but shortened four week course. They were assessed at baseline and at completion by the Chronic Respiratory Questionnaire (CRQ), the Breathing Problems Questionnaire (BPQ), the incremental shuttle walking test (SWT), and the treadmill endurance test (TET).
  
  
  RESULTS
  Twenty one patients (61% men) of mean (SD) age 68 (9.2) years and forced expiratory volume in one second ( FEV(1)) 1.08 (0.4) l completed a conventional seven week course and 23 (67% men) of mean (SD) age 69 (8.8) years and FEV(1) 1.03 (0.3) l completed a shortened four week course. Patients who completed the seven week rehabilitation programme had greater improvements in all outcome measures than those undertaking the four week course. These differences reached clinical and statistical significance for the total CRQ score, which was the primary outcome variable (mean difference (95% confidence intervals (CI) of difference) -0.61(-0.15 to -1.08), p<0.05), and the CRQ domains of dyspnoea (-0.80 (95% CI -0.13 to -1.48), p<0.05), emotion (-0.89 (95% CI -0.33 to -1.45), p<0.005), and mastery (-0.84 (95% CI -0.10 to -1.58), p<0.05). There were also trends towards greater improvements in exercise assessments in the seven week group but the differences did not reach statistical significance (SWT: mean difference -16.9 (95% CI 24.8 to -58.6), p=0.41; TET: geometric mean difference -1.21 (95% CI -0.60 to -2.47), p=0.56).
  
  
  CONCLUSIONS
  A seven week course of pulmonary rehabilitation provides greater benefits to patients than a four week course in terms of improvements in health status. Larger prospective studies are required to determine the optimal duration of a pulmonary rehabilitation programme.
authors.affiliation: Department of Respiratory Medicine, Glenfield Hospital, Groby Road, Leicester LE3 9PQ, UK.
authors.forename: R H
authors.initials: RH
authors.lastname: Green
authors.forename: S J
authors.initials: SJ
authors.lastname: Singh
authors.forename: J
authors.initials: J
authors.lastname: Williams
authors.forename: M D
authors.initials: MD
authors.lastname: Morgan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005080:Exercise Test; D005260:Female; D006304:Health Status; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000534:rehabilitation*; D008297:Male; D008875:Middle Aged; D026741:Physical Therapy Modalities / Q000379:methods*; D013997:Time Factors