Clinical and Prognostic Implications of Cognitive Dysfunction and Depression in COPD

In chronic obstructive pulmonary disease (COPD), cognitive dysfunction - mainly of secondary memory, executive, and constructional abilities - is a marker of disease severity with important clinical and prognostic implications. It correlates with poor compliance with pharmacological therapy, and poor compliance, in turn, increases the cost/effectiveness ratio of home care programs. Executive dysfunction is associated with difficulty with inhaler devices and should be systematically evaluated before prescribing. Drawing impairment has been associated with mortality, although the underlying neurologic abnormalities (right insular damage with autonomic dysfunction or subcortical damage) remain to be defined. Depression is also negatively correlated with survival, besides being a risk factor for quitting respiratory rehabilitation. Cognitive dysfunction should always be considered among the systemic effects of COPD and be the object of systematic screening in COPD patients. Identifying cognitive impairment would prompt either interventions promoting the adherence to the therapy or further investigations to exclude respiratory (nocturnal or effort hypoxemia, coexistent obstructive sleep apnoea) or non respiratory (decompensated diabetes, hypoglycaemic crises, poorly controlled hypertension etc.) causes of cognitive dysfunction. Cognitive enhancing strategies deserve consideration in the framework of a comprehensive approach aimed at improving the health status of people with COPD.