Cognitive function during exacerbations of chronic obstructive pulmonary disease

Abstract

Background The reported prevalence of cognitive impairment in patients with stable chronic obstructive pulmonary disease (COPD) ranges 36‐77%. Few studies report the prevalence of cognitive impairment in acutely unwell COPD patients. Aims To determine the prevalence and time course of cognitive impairment in patients with COPD during and after an admission to hospital with an exacerbation of the disease. Methods Patients admitted to hospital with an exacerbation of COPD between October 2013 and November 2014 were administered the Montreal Cognitive Assessment tool, COPD assessment test and modified Borg dyspnoea scale at three points in time: within 24 h of admission, between 48 and 72 h after admission and 6 weeks post discharge. Results Twenty‐five patients agreed to participate. Four withdrew from the study after the initial evaluation. The mean (range) COPD assessment test score 24 h after admission was 26 (18–37). Cognitive impairment was found in 19/25 (76%) patients at the initial evaluation, 16/21 (76%) patients at the second evaluation. Overall, 22/25 (88%) showed cognitive impairment within 72 h of an exacerbation of COPD. Fourteen out of 21 (66%) patients showed cognitive impairment at the final evaluation. The mean Montreal Cognitive Assessment scores improved from admission (22.6) to the second evaluation (23.3) to the final evaluation 3 (24.4), but this change was not statistically significant. Conclusion Cognitive impairment is highly prevalent during hospital admissions with an exacerbation of COPD. This impairment does improve with time, but only a minority recover within a normal range. This will affect patients’ abilities to understand and remember information given to them in hospital and adhere to medication regimens.

Cognitive function following pulmonary rehabilitation and post-discharge recovery from exacerbation in people with COPD

“…Dodd et al [11] also found no improvement in cognitive performance at 3-months post-discharge using a comprehensive neuropsychological assessment. However, there are inconsistencies in methodology across studies and, as such, other studies have shown an improvement in cognition following recovery [15,17,18]. These methodological differences make direct comparisons between studies difficult, as the timings of the baseline assessment (e.g.…”

“…Differences observed in other studies may be related to the assessment of cognitive function soon after hospital admission. Poot et al [18] and Lopez-Torres et al [17] saw a significant improvement in cognition following a 6-8-week and 1-month recovery, respectively, but both baselines were taken during time of exacerbation. By aligning our baseline assessment of cognition with the approximate timing of PR offer, the present study found that mild-moderate cognitive impairment should not be considered as a reason to delay the offering to the post-discharge phase.…”

“…Dodd et al [11] were first to assess cognitive changes following recovery post-discharge, identifying no improvement. Although the natural recovery of symptoms, physiology and health-related quality of life post-exacerbation has been documented [15,16], the recovery of cognition in relation to other health markers is less consistent [11,15,17,18]. Studies have identified the improvement of lung function, dyspnoea and COPD symptoms following recovery from AECOPD [15,17,18], and Dodd et al [11] found an association between health-related quality of life and cognitive impairment at the time of exacerbation, but a complete assessment is yet to be explored in a single cohort.…”

“…Although the natural recovery of symptoms, physiology and health-related quality of life post-exacerbation has been documented [15,16], the recovery of cognition in relation to other health markers is less consistent [11,15,17,18]. Studies have identified the improvement of lung function, dyspnoea and COPD symptoms following recovery from AECOPD [15,17,18], and Dodd et al [11] found an association between health-related quality of life and cognitive impairment at the time of exacerbation, but a complete assessment is yet to be explored in a single cohort. Processing speed, language and attention have all found to be impaired following hospitalisation for an exacerbation [11,13,17], however the recovery of cognitive performance and other health markers 1-3 months post-discharge is unclear.…”

Cognitive impairment in COPD: an often overlooked co-morbidity

“…During acute exacerbations patients with COPD have been found to have worse cognitive impairment than similar patients with acute heart failure [17]. This acute cognitive deterioration is seen to improve over 6 weeks in most, but not in all patients [18]. Whether exacerbations change cognition in the long term is unclear [19].…”