One hundred years of respiratory medicine chronic obstructive pulmonary disease (COPD)—Republished article

Trends in hospital admissions for obstructive lung disease from 2000 to 2010 in Portugal

The burden of hospitalisations for obstructive lung diseases (OLD) has not been sufficiently studied. We aimed to characterise the hospitalisations for OLD from 2000 to 2010 in all Portuguese public hospitals. We analysed hospital discharges with a diagnosis of OLD regarding the patients' gender, age, residence and comorbidities. Of the 120 399 hospital admissions with a principal diagnosis of OLD, COPD (ICD-9-CM 491.x, 492.x, 496) was responsible for 81%. The change in patients discharged with OLD as a principal diagnosis was only 1% from 2000 to 2010 and did not change for COPD. Hospital admissions and deaths for COPD and other OLD increased with age and were more common in men than women. In-hospital mortality for COPD decreased 34.1% from 2000 to 2010, while the median length of stay was fairly constant at 8 days. Respiratory failure, insufficiency and/or arrest, and pneumonia, are the principal diagnoses often associated with COPD. When both pneumonia and COPD were diagnosed there was an increasing trend to classify pneumonia as the principal diagnosis (64.4%-72.9%), a sign that may lead to underestimation of COPD hospitalisations. In summary, a considerable decrease in in-hospital COPD mortality was observed while hospital admissions and the length of stay did not change substantially. These results suggest that better healthcare or other factors may be counteracting the expected increase of the burden of COPD.

Effects of chronic obstructive pulmonary disease and obstructive sleep apnea on cognitive functions: evidence for a common nature

Patients with chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea syndrome (OSAS) show similar neurocognitive impairments. Effects are more apparent in severe cases, whereas in moderate and mild cases the effects are equivocal. The exact mechanism that causes cognitive dysfunctions in both diseases is still unknown and only suggestions have been made for each disease separately. The primary objective of this review is to present COPD and OSAS impact on cognitive functions. Secondly, it aims to examine the potential mechanisms by which COPD and OSAS can be linked and provide evidence for a common nature that affects cognitive functions in both diseases. Patients with COPD and OSAS compared to normal distribution show significant deficits in the cognitive abilities of attention, psychomotor speed, memory and learning, visuospatial and constructional abilities, executive skills, and language. The severity of these deficits in OSAS seems to correlate with the physiological events such as sleep defragmentation, apnea/hypopnea index, and hypoxemia, whereas cognitive impairments in COPD are associated with hypoventilation, hypoxemia, and hypercapnia. These factors as well as vascocerebral diseases and changes in systemic hemodynamic seem to act in an intermingling and synergistic way on the cause of cognitive dysfunctions in both diseases. However, low blood oxygen pressure seems to be the dominant factor that contributes to the presence of cognitive deficits in both COPD and OSAS.