The 2011 recommendations of the Global initiative for chronic Obstructive Lung Disease (GOLD) constituted a major paradigm shift in COPD management since they set 2 major goals for the assessment and management of patients: (1) the reduction of their current level of symptoms (i.e., treat the patient today); and (2) the reduction of their risk of exacerbations (i.e., prevent them tomorrow). Exacerbations are not only an important clinical endpoint in patients with COPD, but they are also a risk factor themselves for additional adverse outcomes since they have been shown to increase the risk for mortality, to accelerate the decline in pulmonary function, and to decrease health status and quality of life. Despite their importance, many unanswered questions related to exacerbations remain. The purpose of this review is to discuss: (1) knowns and unknowns in our current understanding of exacerbations,
COPD Exacerbations: Knowns and UnknownsThe 2011 recommendations of the Global initiative for chronic Obstructive Lung Disease (GOLD) propose that the assessment and treatment of COPD patients should be structured around 2 major goals: the reduction of the current level of symptoms (i.e., treat the patient today); and, the reduction of the risk of future exacerbations of the disease (COPD exacerbations) (i.e., prevent them tomorrow).1 The latter is a major step forward for COPD, in many ways similar to that achieved by cardiologists decades ago when they realized that they should treat not only symptoms (dyspnea) or acute events (angina), but also to reduce the risk of future events by decreasing arterial blood pressure and/or cholesterol levels. Further, COPD exacerbations are not only important clinical endpoints in themselves, 2-5 but also increase the risk for mortality 6,7 accelerate the decline in pulmonary function,8-11 worsen cardiovascular comorbidities,
12,13decrease health status, 14,15 and impair activities of daily living.
16-18Despite their importance, many questions related to COPD exacerbations remain unanswered. The purpose of this paper is to review the current state of the art with respect to prevention of COPD exacerbations. Specifically, it discusses: (1)knowns and unknowns in our current understanding of COPD exacerbations, (2) factors that increase their risk, and (3)how to prevent them. It does not discuss the adequacy of the treatment of these episodes