The Diagnosis and Treatment of COPD and Its Comorbidities.

Chronic obstructive pulmonary disease (COPD) is the third most common cause of death around the world. The affected patients suffer not only from impaired lung function, but also from a wide variety of comorbidities. Their cardiac comorbidities, in particular, lead to increased mortality.This review is based on pertinent publications retrieved by a selective search in PubMed, including guidelines from Germany and abroad.The usual diagnostic criteria for COPD are a post-bronchodilator FEV1/FVC quotient below the fixed threshold of 0.7, or, preferably, below the lower limit of normal (LLN) according to the GLI reference values for the avoidance of over- and underdiagnosis. The overall prognosis is markedly affected by comorbidities of the lung itself and those that involve other organs; in particular, many persons with COPD die of heart disease. The potential presence of heart disease must be borne in mind in the evaluation of patients with COPD, as lung disease can impair the detection of heart disease.As patients with COPD are often multimorbid, the early diagnosis and adequate treatment not only of their lung disease, but also of their extrapulmonary comorbidities are very important. Well-established diagnostic instruments and well-tested treatments are available and are described in detail in the guidelines concerning the comorbidities. Preliminary observations suggest that more attention should be paid to the potential positive effects of treating comorbidities on the lung disease itself, and vice versa.