***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: PURPOSE Acute exacerbations of chronic obstructive pulmonary disease ( AE COPD ) impair health-related quality of life ( HRQL ) . We evaluated the effect of an abbreviated repeat pulmonary rehabilitation ( PR ) program on HRQL after an AE COPD . METHODS Patients who had completed PR were followed for up to 12 months to identify an AE COPD and then placed in r and omized groups to receive a 3-week repeat-PR intervention or usual care .  Measures of HRQL ( Chronic Respiratory Disease Question naire , CRQ ) and functional exercise capacity ( 6-minute walk distance , 6MWD ) were collected at 2 ( T1 ) , 5 ( T2 ) , and 12 weeks ( T3 ) post-AE COPD . The repeat-PR program was undertaken between T1 and T2 . Between-group differences were examined using repeated- measures analysis of variance or covariance . RESULTS Of the 60 patients ( 30 men , age 69±8 years , forced expiratory volume in 1 second 0.86±0.40 L , 6MWD 367±99 m ) followed , 41 experienced an AE COPD 14 ± 11 weeks after completion of the initial PR program and 33 completed the study . Of these , 16 and 17 were r and omized to the intervention and control groups , respectively . No between-group differences were demonstrated at T2 or T3 . With the exclusion of 5 subjects who experienced a second AE COPD between T1 and T3 , the participants in the intervention group demonstrated greater reduction in dyspnea when compared to those in the control group at T3 ( 0.8±1.6 vs −0.4±1.3 points per item , P = .04 ) . CONCLUSIONS The reduction in dyspnea in those who did not experience a second AE COPD provides preliminary evidence for the role of repeat programs . The application of repeat PR should be refined in larger trials BACKGROUND Pulmonary rehabilitation programmes improve the health of patients disabled by lung disease but their cost effectiveness is unproved . We undertook a cost/utility analysis in conjunction with a r and omised controlled clinical trial of pulmonary rehabilitation versus st and ard care . METHODS Two hundred patients , mainly with chronic obstructive pulmonary disease , were r and omly assigned to either an 18 visit , 6 week rehabilitation programme or st and ard medical management . The difference between the mean cost of 12 months of care for patients in the rehabilitation and control groups ( incremental cost ) and the difference between the two groups in quality adjusted life years ( QALYs ) gained ( incremental utility ) were determined . The ratio between incremental cost and utility ( incremental cost/utility ratio ) was calculated . RESULTS Each rehabilitation programme for up to 20 patients cost £ 12 120 . The mean incremental cost of adding rehabilitation to st and ard care was £ –152 ( 95 % CI –881 to 577 ) per patient , p = NS . The incremental utility of adding rehabilitation was 0.030 ( 95 % CI 0.002 to 0.058 ) QALYs per patient , p=0.03 . The point estimate of the incremental cost/utility ratio was therefore negative . The bootstrapping technique was used to model the distribution of cost/utility estimates possible from the data . A high likelihood of generating QALYs at negative or relatively low cost was indicated . The probability of the cost per QALY generated being below £ 0 was 0.64 . CONCLUSIONS This outpatient pulmonary rehabilitation programme produces cost per QALY ratios within bounds considered to be cost effective and is likely to result in financial benefits to the health service In recent years quality of life instruments have been featured as primary outcomes in many r and omized trials . One of the challenges facing the investigator using such measures is determining the significance of any differences observed , and communicating that significance to clinicians who will be applying the trial results . We have developed an approach to elucidating the significance of changes in score in quality of life instruments by comparing them to global ratings of change . Using this approach we have established a plausible range within which the minimal clinical ly important difference ( MCID ) falls . In three studies in which instruments measuring  dyspnea , fatigue , and emotional function in patients with chronic heart and lung disease were applied the MCID was represented by mean change in score of approximately 0.5 per item , when responses were presented on a seven point Likert scale . Furthermore , we have established ranges for changes in question naire scores that correspond to moderate and large changes in the domains of interest . This information will be useful in interpreting question naire scores , both in individuals and in groups of patients participating in controlled trials , and in the planning of new trials Background The feasibility of r and omized trials often depends on successful patient recruitment . Although numerous recruitment barriers have been identified it is unclear which of them complicate recruitment most . Also , most surveys have focused on the patients ' perspective of recruitment barriers whereas the perspective of recruiting physicians has received less attention . Therefore , our aim was to conduct a postal survey among recruiting physicians of a multi-center trial to weigh barriers according to their impact on recruitment . Methods We identified any potential recruitment barriers from the literature and from our own experience with a multi-center trial of respiratory rehabilitation in patients with chronic obstructive pulmonary disease . We developed and pilot-tested a self-administered question naire where recruiting physicians were asked to express their agreement with statements about recruitment barriers on a Likert-type scale from 1 ( full agreement with statement = very substantial recruitment barrier ) to 7 ( no agreement with statement = no recruitment barrier ) . Results 38 of 55 recruiting physicians returned question naires ( 69 % response rate ) , of which 35 could be analyzed ( 64 % useable response rate ) . Recruiting physicians reported that " time constraints " ( median agreement of 3 , interquartile range 2–5 ) had the most negative impact on recruitment followed by " difficulties including identified eligible patients " ( median agreement of 5 , IQR 3–6 ) . Other barriers such as " trial design barriers " , " lack of access to treatment " , " individual barriers of recruiting physicians " or " insufficient training of recruiting physicians " were perceived to have little or no impact on patient recruitment . Conclusion Physicians perceived time constraints as the most relevant recruitment barrier in a r and omized trial . To overcome recruitment barriers interventions , that are affordable for both industry- and investigator-driven trials , need to be developed and tested in r and omized trials . Trial registration IS RCT We examined the feasibility of home-based walking training to maintain the benefits of a short-term exercise training in patients with severe chronic obstructive pulmonary disease ( COPD ) . After initial recovery from an exacerbation , 46 patients were r and omized into a training and a control group , and 30 patients completed the programme ( mean + /- SD FEV1 , 36 + /- 7 % predicted ) . The training group performed a 10-day walking training programme in the hospital , followed by a 6-month programme of supervised walking training at home , integrated into daily activities . The control group did not have exercise training in the hospital or at home . Until 6 months after discharge , lung function , exercise performance and symptom scores were assessed . Six-minute walking distance in the training group improved from day 1 to day 10 ( P<0.001 ) and this effect was maintained over 6 months ( P<0.001 ) . On average , daily walking distance at home was 2308 m and walking was reported on 157 days . Quality of life ( QoL ) scores changed significantly over 6 months ( P<0.001 ) . The control group showed no significant changes in exercise performance or QoL scores throughout the whole study period . Therefore , ( i ) significant improvements in exercise performance and Chronic Respiratory Disease Question naire ( CRQ ) scores could be achieved after recovery from an exacerbation and ( ii ) these improvements were maintained after discharge , when supported by a home-based walking training The aim of this study was to assess long-term mortality and predictive factors of death after hospital admission for acute exacerbation of chronic obstructive pulmonary disease ( COPD ) . 1824 patients ( 23.2 % female ; mean age 70.3±11.3 years ) consecutively admitted for acute exacerbation of COPD in the respiratory medicine departments of 68 general hospitals between October 2006 and June 2007 were prospect ively enrolled in a follow-up cohort . Their vital status was documented between October 2010 and April 2011 . Vital status was available for 1750 patients ( 95.9 % ) , among whom 787 ( 45 % ) died during follow-up . Multivariate analysis found that age ( 60–80 years and ≥80 years versus < 60 years , relative risk 2.99 , 95 % CI 2.31–3.89 ) , lower body mass index ( 25–30 kg·m−2 versus ≤20 kg·m−2 , relative risk 0.80 , 95 % CI 0.66–0.97 ) , lung cancer ( relative risk 2.08 , 95 % CI 1.43–3.01 ) , cardiovascular comorbidity ( relative risk 1.35 , 95 % CI 1.16–1.58 ) , previous hospital admissions for acute exacerbation of COPD ( four or more versus none , relative risk 1.91 , 95 % CI 1.44–2.53 ) , use of accessory respiratory muscles ( relative risk 1.19 , 95 % CI 1.01–1.40 ) or lower-limb oedema ( relative risk 1.74 , 95 % CI ( 1.44–2.12 ) ) at admission and treatment by long-term oxygen therapy at discharge ( relative risk 2.09 , 95 % CI 1.79–2.45 ) were independent risk factors of death . Mortality rate during the 4 years following hospital admission for acute exacerbation of COPD was high ( 45 % ) . Simple clinical information relating to respiratory and general status can help in identifying high-risk patients and targeting more intensive follow-up and care . Interestingly , cardiovascular comorbidities and past hospitalisations for acute exacerbation of COPD , but not forced expiratory volume in 1 s , independently predicted the risk of death . Long-term risk of death after hospitalisation for acute exacerbation of COPD is high but can be readily identified Clinical trials identifier NCT02329873 Background Acute exacerbation ( AE ) of COPD is characterized by a sudden worsening of COPD symptoms . Previous studies have explored the effectiveness of respiratory rehabilitation for patients with COPD ; however , no training program specific to acute exacerbation in elderly patients or unstable periods during hospitalization has been developed . Objective To evaluate the effects of a respiratory rehabilitation exercise training package on dyspnea , cough , exercise tolerance , and sputum expectoration among hospitalized elderly patients with AE COPD . Methods A r and omized control trial was conducted . Pretest and posttest evaluations of 61 elderly in patients with AE COPD ( experimental group n=30 ; control group n=31 ) were performed . The experimental group received respiratory rehabilitation exercise training twice a day , 10–30 minutes per session for 4 days . The clinical parameters ( dyspnea , cough , exercise tolerance , and sputum expectoration ) were assessed at the baseline and at the end of the fourth day . Results All participants ( median age = 70 years , male = 60.70 % , and peak expiratory flow 140 L ) completed the study . In the patients of the experimental group , dyspnea and cough decreased and exercise tolerance and sputum expectoration increased significantly compared with those of the patients in the control group ( all P<0.05 ) . Within-group comparisons revealed that the dyspnea , cough , and exercise tolerance significantly improved in the experimental group by the end of the fourth day ( all P<0.05 ) . Conclusion Results of this study suggest that the respiratory rehabilitation exercise training package reduced symptoms and enhanced the effectiveness of the care of elderly in patients with AE COPD Background : Around the world , the timing of referral of chronic obstructive pulmonary disease ( COPD ) patients for  pulmonary rehabilitation differs from immediately after exacerbation ( early ) to later on when patients are in a stable state ( late ) . There are no trials comparing the different time points of referral for pulmonary rehabilitation . Objectives : Our aim was to compare the effects of early and late pulmonary rehabilitation on exacerbation rates and health-related quality of life ( HRQOL ) in COPD patients with exacerbations . Methods : We r and omized COPD patients ( Global Initiative for Chronic Obstructive Lung Disease stages II – IV ) with a recent exacerbation to early ( within 2 weeks ) or late pulmonary rehabilitation ( starting 6 months after r and omization and in a stable state ) . The primary outcome was the exacerbation rate over 18 months , and secondary outcomes included HRQOL and mortality . We used multivariate analyses and an intention-to-treat analysis approach . Results : We r and omized 36 patients to pulmonary rehabilitation .  On average , patients with early rehabilitation ( n = 19 ) had 2.61 ( SD 2.96 ) exacerbations requiring systemic corticosteroids and /or antibiotics , compared to 2.77 ( SD 3.41 ) in patients with late rehabilitation  ( adjusted incidence rate ratio 0.83 , 95 % confidence interval 
    Output:
    
Hospital readmissions and mortality studies newly included in this up date showed , on average , significantly smaller effects of rehabilitation than were seen in earlier studies .High- quality evidence suggests that pulmonary rehabilitation after an exacerbation improves health-related quality of life .
AUTHORS ' CONCLUSIONS Overall , evidence of high quality shows moderate to large effects of rehabilitation on health-related quality of life and exercise capacity in patients with COPD after an exacerbation .