Cognitive and perceived health status in patient with chronic obstructive pulmonary disease surviving acute on chronic respiratory failure: a controlled study.

OBJECTIVE: To evaluate the perceived health and cognitive status in survivors of chronic obstructive pulmonary disease (COPD) exacerbations requiring mechanical ventilation. DESIGN AND
SETTING: Prospective controlled cohort study in a respiratory intermediate intensive care unit. PATIENTS: Sixty-three COPD patients at their first episode of acute on chronic respiratory failure requiring mechanical ventilation, controls were 34 consecutive stable COPD patients on long-term oxygen therapy with no previous ICU admission. MEASUREMENTS AND
RESULTS: Perceived health and cognitive status by means of the Nottingham Health Profile (NHP) and the Mini Mental State (MMS), respectively, at discharge and 3 and 6 months thereafter. At discharge patients showed significantly worse mean values than controls in MMS and in all NHP dimensions except pain. The MMS score was below 24, the threshold level of cognitive impairment, in 43% patients of the study group but only 3% of controls ( p=0.006). Six months after discharge patients showed NHP and MMS values similar to those of controls and the proportion of patients with a MMS score below 24 had significantly decreased to 17%, a value not significantly different from that in controls (5%).
CONCLUSIONS: COPD patients surviving their first episode of acute on chronic respiratory failure requiring mechanical ventilation, suffer worsen perceived health status and cognitive function, which 6 months after discharge may improve to levels similar to those in stable COPD patients on long-term oxygen therapy with no previous ICU admission.