@article{7b2161d6a3dd4d728970a7105722f5d2,
title = "What have we learned from large drug treatment trials in COPD?",
abstract = "Although the development of effective treatments for patients with chronic obstructive pulmonary disease (COPD) has not been seen as a high priority, the past decade has seen a substantial increase in the number of clinical studies examining different treatments for this disease. Large studies are needed to adequately assess the effectiveness of treatment because of the chronic nature of the disease and the intermittent occurrence of some key outcomes such as exacerbations. Data from randomised controlled trials show that treatment improves exercise performance by increasing lung volume rather than changing expiratory flow. Although assessment of lung function remains the cornerstone of drug assessment, improvements in health status, the number of exacerbations and admissions to hospital are now recognised as important treatment outcomes. Randomised controlled trial data provide the best evidence for treatment efficacy, but results of these studies can be affected by differences in inclusion criteria and patient dropout during the study. Bronchodilator reversibility testing does not reliably define subgroups that will respond to a particular treatment. Carefully done and adequately powered clinical trials continue to inform, not only our views about treatment, but also our understanding of COPD and how it is best assessed and managed. Ensuring that these expensive studies are done objectively to the highest standard is an important goal for the next decade.",
author = "Calverley, {Peter MA} and Rennard, {Stephen I.}",
note = "Funding Information: Although most studies in the past 10 years have been funded by the health-care industry or with some Government sponsorship, the first studies defining the clinical course of COPD were entirely funded by governments. Thus, the landmark study of Fletcher and colleagues 10 in a stratified random sample of 792 British men was supported by the British Medical Research Council. They tested the hypothesis that the presence of cough and sputum identified patients with a worse natural history of disease compared with those without cough or sputum production. 10 The unexpected conclusion, that the degree of airflow obstruction determined disease progression, has affected the subsequent definition of COPD and provided a clear rationale for the role of spirometry in diagnosis. This study also led directly to a difficult therapeutic target, namely the slowing of the decline in lung function over time, which has subsequently been studied in detail. Results in other general populations have supported the longitudinal findings of Fletcher and Peto 11,12 about the association of decline in lung function with tobacco smoking, but the US National Heart Lung and Blood Institute (NHLBI)-supported Lung Health Study in nearly 6000 North American smokers with mild COPD showed beyond doubt that smoking cessation, and treatment in a smoking cessation programme had beneficial effects on lung function decline 13,14 and other important outcomes such as mortality. 15 ",
year = "2007",
month = sep,
day = "1",
doi = "10.1016/S0140-6736(07)61381-6",
language = "English (US)",
volume = "370",
pages = "774--785",
journal = "Lancet",
issn = "0140-6736",
publisher = "Elsevier B.V.",
number = "9589",
}