RationalePulmonary rehabilitation (PR) is an effective, key standard treatment for people with COPD. Nevertheless, low participant uptake, insufficient attendance and high drop-out rates are reported. Investigation is warranted of the benefits achieved through alternative approaches, such as pulmonary tele-rehabilitation (PTR).ObjectiveTo investigate whether PTR is superior to conventional PR on 6 min walk distance (6MWD) and secondarily on respiratory symptoms, quality of life, physical activity and lower limb muscle function in patients with COPD and FEV1 <50% eligible for routine hospital-based, outpatient PR.MethodsIn this single-blinded, multicentre, superiority randomised controlled trial, patients were assigned 1:1 to 10 weeks of groups-based PTR (60 min, three times weekly) or conventional PR (90 min, two times weekly). Assessments were performed by blinded assessors at baseline, end of intervention and at 22 weeks’ follow-up from baseline. The primary analysis was based on the intention-to-treat principle.Measurements and main resultsThe primary outcome was change in 6MWD from baseline to 10 weeks; 134 participants (74 females, mean±SD age 68±9 years, FEV1 33%±9% predicted, 6MWD 327±103 metres) were included and randomised. The analysis showed no between-group differences for changes in 6MWD after intervention (9.2 metres (95% CI: −6.6 to 24.9)) or at 22 weeks’ follow-up (−5.3 metres (95% CI: −28.9 to 18.3)). More participants completed the PTR intervention (n=57) than conventional PR (n=43) (χ2 test p<0.01).ConclusionPTR was not superior to conventional PR on the 6MWD and we found no differences between groups. As more participants completed PTR, supervised PTR would be relevant to compare with conventional PR in a non-inferiority design.Trial registration numberClinicalTrials.gov (NCT02667171), 28 January 2016.

Context Many smokers are unable or unwilling to completely quit smoking. A proposed means of harm reduction is to reduce the number of cigarettes smoked per day. However, it is not clear whether this strategy decreases the risk for tobacco-related diseases. Objective To assess the effects of smoking reduction on lung cancer incidence. Design, Setting, and Participants Observational population-based cohort study with up to 31 years of follow-up from the Copenhagen Centre for Prospective Population Studies, which administrates data from 3 longitudinal studies conducted in Copenhagen and suburbs, the Copenhagen City Heart Study, the Copenhagen Male Study, and the Glostrup Population Studies, Denmark. Participants were 11 151 men and 8563 women (N=19 714) aged 20 to 93 years, who attended 2 consecutive examinations with a 5-to 10-year interval between 1964 and 1988. Participants underwent a physical examination and completed self-filled questionnaires about lifestyle habits. The study population was divided into 6 groups according to smoking habits: continued heavy smokers (Ն15 cigarettes/d), reducers (reduced from Ն15 cigarettes/d by minimum of 50% without quitting), continued light smokers (1-14 cigarettes/d), quitters (stopped between first and second examination), stable ex-smokers, and never smokers. Main Outcome Measure Incident primary lung cancer cases assessed by record linkage with the National Cancer Registry until December 31, 2003. Results There were 864 incident lung cancers during follow-up. Using Cox regression, the adjusted hazard ratio (HR) for lung cancer in reducers was 0.73 (95% confidence interval [CI], 0.54-0.98) compared with persistent heavy smokers. The HR for light smokers was 0.44 (95% CI, 0.35-0.56); for quitters, HR 0.50 (95% CI, 0.36-0.69), for stable ex-smokers, HR 0.17 (95% CI, 0.13-0.23), and for never smokers, HR 0.09 (95% CI, 0.06-0.13). Conclusion Among individuals who smoke 15 or more cigarettes per day, smoking reduction by 50% significantly reduces the risk of lung cancer.

The evidence base for the benefit of quitting smoking as regards morbidity and mortality outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD) is limited.The present article is a review of the existing literature. A systematic literature search in medical databases was performed until March 2006, and subsequently until September 1, 2007. The outcomes examined were COPD-related morbidity and mortality (including all-cause mortality) in COPD patients in connection with smoking cessation.A total of 21 and 27 published articles on morbidity and mortality, respectively, were identified and reviewed. For both outcomes, only a few of the studies included patients with severe COPD. Most of the studies reported a beneficial effect of smoking cessation compared with continued smoking, whereas a few found no improvement. Methodological problems, including small study sizes, poor data quality, possibility of reverse causality and incomplete ascertainment of cause of death, limit interpretation of some of the studies.The evidence as a whole supports the conclusion that, even in severe chronic obstructive pulmonary disease, smoking cessation slows the accelerated rate of lung function decline and improves survival compared with continued smoking.

Background: Few studies have investigated the 24-hour symptom profile in patients with COPD or how symptoms during the 24-hour day are inter-related. This observational study assessed the prevalence, severity and relationship between night-time, early morning and daytime COPD symptoms and explored the relationship between 24-hour symptoms and other patient-reported outcomes. Methods: The study enrolled patients with stable COPD in clinical practice. Baseline night-time, early morning and daytime symptoms (symptom questionnaire), severity of airflow obstruction (FEV 1 ), dyspnoea (modified Medical Research Council Dyspnoea Scale), health status (COPD Assessment Test), anxiety and depression levels (Hospital Anxiety and Depression Scale), sleep quality (COPD and Asthma Sleep Impact Scale) and physical activity level (sedentary, moderately active or active) were recorded. Results: The full analysis set included 727 patients: 65.8% male, mean ± standard deviation age 67.2 ± 8.8 years, % predicted FEV 1 52.8 ± 20.5%. In each part of the 24-hour day, >60% of patients reported experiencing ≥1 symptom in the week before baseline. Symptoms were more common in the early morning and daytime versus night-time (81.4%, 82.7% and 63.0%, respectively). Symptom severity was comparable for each period assessed. Overall, in the week before baseline, 56.7% of patients had symptoms throughout the whole 24-hour day (3 parts of the day); 79.9% had symptoms in ≥2 parts of the 24-hour day. Symptoms during each part of the day were inter-related, irrespective of disease severity (all p < 0.001). Early morning and daytime symptoms were associated with the severity of airflow obstruction (p < 0.05 for both). Nighttime, early morning and daytime symptoms were all associated with worse dyspnoea, health status and sleep quality, and higher anxiety and depression levels (all p < 0.001 versus patients without symptoms in each corresponding period). In each part of the 24-hour day, there was also an association between symptoms and a patient's physical activity level (p < 0.05 for each period).

The authors investigated the association between changes in smoking habits and mortality by pooling data from three large cohort studies conducted in Copenhagen, Denmark. The study included a total of 19,732 persons who had been examined between 1967 and 1988, with reexaminations at 5- to 10-year intervals and a mean follow-up of 15.5 years. Date of death and cause of death were obtained by record linkage with nationwide registers. By means of Cox proportional hazards models, heavy smokers (>or=15 cigarettes/day) who reduced their daily tobacco intake by at least 50% without quitting between the first two examinations and participants who quit smoking were compared with persons who continued to smoke heavily. After exclusion of deaths occurring in the first 2 years of follow-up, the authors found the following adjusted hazard ratios for subjects who reduced their smoking: for cardiovascular diseases, hazard ratio (HR) = 1.01 (95% confidence interval (CI): 0.76, 1.35); for respiratory diseases, HR = 1.20 (95% CI: 0.70, 2.07); for tobacco-related cancers, HR = 0.91 (95% CI: 0.63, 1.31); and for all-cause mortality, HR = 1.02 (95% CI: 0.89, 1.17). In subjects who stopped smoking, most estimates were significantly lower than the heavy smokers'. These results suggest that smoking reduction is not associated with a decrease in mortality from tobacco-related diseases. The data confirm that smoking cessation reduces mortality risk.