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

The effect of rosemary hydroalcoholic extract on cognitive function and activities of daily living of patients with chronic obstructive pulmonary disease (COPD): A clinical trial

BACKGROUND

In patients living with chronic obstructive pulmonary disease (COPD), cognitive impairment and reduced activities of daily living (ADLs) are associated with poor clinical outcomes.

AIM

The aim of the present study was to determine the effect of rosemary hydroalcoholic extract on cognitive function and ADLs in patients with COPD.

METHODS

A total of 77 COPD patients aged 40-80 years were assigned to two intervention and control groups by random stratified block method in the current tripleblind clinical trial. The intervention group received 500 mg rosemary capsules and the control group received oral capsules containing corn powder twice a day, one to two hours before breakfast and dinner, for two months. The Montreal Cognitive Assessment-Basic (MoCA-B), London Chest Activity of Daily Living scale (LCADL) and Lawton Instrumental Activities of Daily Living (IADL) were used to measure cognitive function and the measure of basic and instrumental daily life activities, before and after the intervention, respectively.

RESULTS

The mean total score of cognitive function (P = 0.022) and the two subscales of abstraction (P = 0.003) and naming (P = 0.034) significantly increased after the intervention in the intervention group. There was no significant difference between the intervention and control groups in terms of changes in the mean scores of IADL and LCADL (P < 0.05). The final statistical model showed that the changes in the total mean score of cognitive function (P = 0.014) and IADL (P = 0.047) in intervention group patients are significantly higher than in the control group after adjusting the effect of obstructive sleep apnea (OSA).

CONCLUSION

The rosemary hydroalcoholic extract can be effective in improving cognitive function and IADL in patients with COPD, but not LCADL.

CLINICAL TRIALS REGISTRATION NUMBER

IRCT20150919024080N16.

Protected characteristics reported in pulmonary rehabilitation: a scoping review

BACKGROUND

An individual's characteristics are reported to influence access, completion and outcomes of pulmonary rehabilitation and may contribute to health inequalities. Many countries have policies to promote equity among individuals' characteristics, including the UK Equality Act 2010 which lists nine protected characteristics (age, disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex and sexual orientation).

OBJECTIVES

To describe the extent to which UK Equality Act 2010 protected characteristics have been collected and reported in UK studies and audits of pulmonary rehabilitation.

METHODS

A scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines was conducted using five databases. UK studies and audits collecting data on pulmonary rehabilitation from 1 October 2010 (date of Equality Act 2010 inception) were eligible. The protected characteristics collected and how they were reported were extracted.

RESULTS

Out of 45 included studies and audits (41 studies and four audits), 98% (k=44) reported age. Sex was reported in 40% (k=18), and 20% (k=9) reported gender with only male and female categories. Half (50%, k=2) of audits reported gender with male, female and transgender categories. Race was reported through ethnicity in 2% (k=1) of studies and 75% (k=3) of audits. No studies or audits explicitly reported disability, but all reported measures indicating disease severity (e.g. forced expiratory volume in 1 s % predicted: 67%, k=30). No studies or audits reported marriage and civil partnership, pregnancy and maternity, religion or belief or sexual orientation.

CONCLUSIONS

Protected characteristics are not commonly reported or are inconsistently reported in UK pulmonary rehabilitation studies and audits. Without reporting these characteristics, health inequalities in pulmonary rehabilitation will remain unclear.

Targeting accelerated pulmonary ageing to treat chronic obstructive pulmonary disease-induced neuropathological comorbidities

Chronic obstructive pulmonary disease (COPD) is a major incurable health burden, ranking as the third leading cause of death worldwide, mainly driven by cigarette smoking. COPD is characterised by persistent airway inflammation, lung function decline and premature ageing with the presence of pulmonary senescent cells. This review proposes that cellular senescence, a state of stable cell cycle arrest linked to ageing, induced by inflammation and oxidative stress in COPD, extends beyond the lungs and affects the systemic circulation. This pulmonary senescent profile will reach other organs via extracellular vesicles contributing to brain inflammation and damage, and increasing the risk of neurological comorbidities, such as stroke, cerebral small vessel disease and Alzheimer's disease. The review explores the role of cellular senescence in COPD-associated brain conditions and investigates the relationship between cellular senescence and circadian rhythm in COPD. Additionally, it discusses potential therapies, including senomorphic and senolytic treatments, as novel strategies to halt or improve the progression of COPD.

Time-Course of Changes in Multidimensional Fatigue and Functional Exercise Capacity and Their Associations during a Short Inpatient Pulmonary Rehabilitation Program

This study aimed to assess the time-course of changes in multidimensional fatigue and functional exercise capacity and their associations during an inpatient pulmonary rehabilitation (PR) program. Seventy COPD patients from three centres were enrolled for a four-week PR program and were evaluated before (T0) and at the end of each week (T1, T2, T3, and T4). Weekly change in multidimensional fatigue was assessed by the multidimensional inventory questionnaire (MFI-20) and functional exercise capacity by the 6-minute walking distance (6MWD). Reaction time (RT) and heart rate variability (HRV) were also assessed as complementary markers of fatigue. HRV did not change during the study (all p > 0.05). MFI-20 score and RT decreased during the first part of the program (p < 0.001) and levelled off at T2 (all p > 0.05 compared with each preceding time). While 6MWD improved by almost 70% during the first part of the PR, it continued to increase, albeit at a greatly reduced pace, between T2 and T4 (p < 0.05). In parallel, a negative association was found between MFI-20 score and 6MWD at each evaluation time (r ranged from 0.43 to 0.71), with a significantly stronger T3 correlation compared with the other time periods (all p < 0.05). The strengthening of the association between fatigue and functional exercise capacity at T3, which occurred concomitantly with the slowdown of functional exercise capacity improvement, is consistent with a role for fatigue in the limitation of performance changes during PR. The limitation of fatigue during PR is thus an interesting aspect to improve the magnitude of performance changes.

The Impact of Pulmonary Rehabilitation on Mental Health and Quality of Life in Patients With Chronic Obstructive Pulmonary Disease (COPD): A Narrative Review

Chronic obstructive pulmonary disease (COPD) is a complex, prevalent, debilitating, and degenerative disease that affects a large population, and the treatment options for the patients are limited. Although progress has been made in COPD pathogenesis, etiology, and management, there is still an unmet need to develop novel therapies. COPD management has recently seen a focus on a multidisciplinary pulmonary rehabilitation approach to help patients manage the disease better. This review primarily focuses on the role of pulmonary rehabilitation as a novel therapeutic strategy for treating and managing COPD, which is known to decrease patients' quality of life. Disease management and the beneficial effects of pulmonary rehabilitation in COPD are discussed. Subsequently, different methods that are employed in pulmonary rehabilitation are examined, including oxygen therapy, exercise, meditation, and education, emphasizing how they can help patients better manage COPD. Pathophysiology and the effect of pulmonary rehabilitation on the cellular level, such as the release of perforins and Th1 and Th17 cytokines, are also explored. The link between exercise and meditation during pulmonary rehabilitation therapy, which promotes repairing affected organs, is emphasized. Future perspectives on personalized medicine and its use in conjunction with pulmonary rehabilitation are also outlined. In conclusion, pulmonary rehabilitation holds significant promise for the management of COPD by addressing the present limitations of treatment. However, further research is essential to overcome and optimize treatment strategies for COPD patients.

The change of attention network functions and physiological adaptation during high-altitude hypoxia and reoxygenation

Previous studies have not reached a definitive conclusion regarding the effect of high-altitude hypoxia and reoxygenation on attention. To clarify the influence of altitude and exposure time on attention and the relations between physiological activity and attention, we conducted a longitudinal study to track attention network functions in 26 college students. The scores on the attention network test and physiological data, including heart rate, percutaneous arterial oxygen saturation (SpO₂), blood pressure, and vital capacity in pulmonary function measurement, were collected at five time-points: two weeks before arriving at high altitude (baseline), within 3 days after arriving at high altitude (HA3), 21 days after arriving at high altitude (HA21), 7 days after returning to sea level (POST7) and 30 days after returning to sea level (POST30). The alerting scores at POST30 were significantly higher than those at baseline, HA3 and HA21; the orienting scores at HA3 were lower than those at POST7 and POST30; the executive control scores at POST7 were significantly lower than those at baseline, HA3, HA21, and POST30; and the executive control scores at HA3 were significantly higher than those at POST30. The change in SpO₂ during high-altitude acclimatization (from HA3 to HA21) was positively correlated with the orienting score at HA21. Vital capacity changes during acute deacclimatization positively correlated with orienting scores at POST7. Attention network functions at the behavioral level did not decline after acute hypoxia exposure compared with baseline. Attention network functions after returning to sea level were improved compared with those during acute hypoxia; additionally, alerting and executive function scores were improved compared with those at baseline. Thus, the speed of physiological adaptation could facilitate the recovery of orienting function during acclimatization and deacclimatization.

The association between total cholesterol and cognitive impairment in chronic obstructive pulmonary disease patients

AIM

Chronic obstructive pulmonary disease (COPD) is primarily a respiratory system disorder associated with extrapulmonary conditions. Cognitive impairment (CoI) is very common among COPD patients This study sought to investigate the association between CoI and clinical parameters, inflammatory markers and lipid profiles in a COPD patient population.

METHODS

The study population included 111 stable COPD patients. COPD was diagnosed according to Global Initiative for Chronic Obstructive Lung Disease guideline. Total complete blood count test and biochemical measurements including lipid profile were performed. Afterwards, all patients underwent neuropsychological assessment including Hospital Anxiety and Depression Scale (HADS), Pittsburgh Sleep Quality Index and Montreal Cognitive Assessment (MoCA) tests.

RESULTS

The patients were categorized into two groups according to their MoCA test score: MoCA score ≤ 21 (CoI) (n = 69) and MoCA score > 21 (normal cognition) (n = 42). Total cholesterol (TC) levels were significantly lower in patients with CoI compared to patients with normal cognition. Inflammation related parameters including C-reactive protein were similar among groups. Multivariate logistic regression analysis yielded education, HADS score and TC (OR:1.02, 95% CI:1.00-1.04, p = 0.025) as independent predictors of MoCA score.

CONCLUSION

TC independently associates with CoI in COPD patients. There is comparable inflammatory status in COPD patients with CoI compared to COPD patients with normal cognition.

Effect of a pulmonary rehabilitation program combined with cognitive training on exercise tolerance and cognitive functions among Tunisian male patients with chronic obstructive pulmonary disease: A randomized controlled trial

BACKGROUND

Cognitive impairment has been well described in patients with Chronic Obstructive Pulmonary Disease (COPD) in addition to cardiorespiratory disability. To reduce this impairment, researchers have recommended the use of single or combined exercise training. However, the combined effect of cognitive training (CT) and pulmonary rehabilitation (PR) program on selective cognitive abilities in patients with COPD has not been fully evaluated. Therefore, we aimed to assess the impact of PR combined with CT on 6 minutes walking test (6MWT) and cognitive parameters in Tunisian males' patients with COPD.

METHODS

Thirty-nine patients with COPD were randomly assigned to an intervention group (n = 21, age = 65.3 ± 2.79) and a control group (n = 18, age = 65.3 ± 3.2). The intervention group underwent PR combined with CT, and the control group underwent only PR, three times per week for 3 months. The primary outcomes were 6MWT (6 minutes walking test -6MWT-parameters) and cognitive performance, as evaluated by Montreal cognitive assessments (MOCA) and P300 test. Secondary outcomes were patient's characteristics and spirometric data. These tests were measured at baseline and after 3 months of training programs.

RESULTS

Results showed a significant improvement of the 6MWT distance after the rehabilitation period in both groups (p < .001). Moreover, both groups showed significant improvement (p < .001) in cognitive performance including MOCA score and P300 test latency in three midline electrodes. However, the improvement in cognitive performance was significantly greater in the PR+CT group than the PR group.

CONCLUSION

In conclusion, although PR alone improves 6MWT parameters and cognitive function, the addition of CT to PR is more effective in improving cognitive abilities in patients with COPD. This combined approach may provide clinicians with a complementary therapeutic option for improving cognitive abilities in patients with COPD.

Impact of cognitive capacity on physical performance in chronic obstructive pulmonary disease patients: A scoping review

Background: Chronic obstructive pulmonary disease (COPD) is often accompanied by impaired cognitive and physical function. However, the role of cognitive function on motor control and purposeful movement is not well studied. The aim of the review was to determine the impact of cognition on physical performance in COPD. Methods: Scoping review methods were performed including searches of the databases: MEDLINE, EMBASE, Cochrane Systematic Reviews, Cochrane (CENTRAL), APA PsycINFO, and CINAHL. Two reviewers independently assessed articles for inclusion, data abstraction, and quality assessment. Results: Of 11,252 identified articles, 44 met the inclusion criteria. The review included 5743 individuals with COPD (68% male) with the forced expiratory volume in one second range of 24-69% predicted. Cognitive scores correlated with strength, balance, and hand dexterity, while 6-min walk distance (n = 9) was usually similar among COPD patients with and without cognitive impairment. In 2 reports, regression analyses showed that delayed recall and the trail making test were associated with balance and handgrip strength, respectively. Dual task studies (n = 5) reported impaired balance or gait in COPD patients compared to healthy adults. Cognitive or physical Interventions (n = 20) showed variable improvements in cognition and exercise capacity. Conclusions: Cognition in COPD appears to be more related to balance, hand, and dual task function, than exercise capacity.

Effects of a nutritional intervention on impaired behavior and cognitive function in an emphysematous murine model of COPD with endotoxin-induced lung inflammation

One cluster of the extrapulmonary manifestations in chronic obstructive pulmonary disease (COPD) is related to the brain, which includes anxiety, depression and cognitive impairment. Brain-related comorbidities are related to worsening of symptoms and increased mortality in COPD patients. In this study, a murine model of COPD was used to examine the effects of emphysema and repetitive pulmonary inflammatory events on systemic inflammatory outcomes and brain function. In addition, the effect of a dietary intervention on brain-related parameters was assessed. Adult male C57Bl/6J mice were exposed to elastase or vehicle intratracheally (i.t.) once a week on three consecutive weeks. Two weeks after the final administration, mice were i.t. exposed to lipopolysaccharide (LPS) or vehicle for three times with a 10 day interval. A dietary intervention enriched with omega-3 PUFAs, prebiotic fibers, tryptophan and vitamin D was administered from the first LPS exposure onward. Behavior and cognitive function, the degree of emphysema and both pulmonary and systemic inflammation as well as blood-brain barrier (BBB) integrity and neuroinflammation in the brain were assessed. A lower score in the cognitive test was observed in elastase-exposed mice. Mice exposed to elastase plus LPS showed less locomotion in the behavior test. The enriched diet seemed to reduce anxiety-like behavior over time and cognitive impairments associated with the presented COPD model, without affecting locomotion. In addition, the enriched diet restored the disbalance in splenic T-helper 1 (Th1) and Th2 cells. There was a trend toward recovering elastase plus LPS-induced decreased expression of occludin in brain microvessels, a measure of BBB integrity, as well as improving expression levels of kynurenine pathway markers in the brain by the enriched diet. The findings of this study demonstrate brain-associated comorbidities - including cognitive and behavioral impairments - in this murine model for COPD. Although no changes in lung parameters were observed, exposure to the specific enriched diet in this model appeared to improve systemic immune disbalance, BBB integrity and derailed kynurenine pathway which may lead to reduction of anxiety-like behavior and improved cognition.

The role of structured exercise interventions on cognitive function in older individuals with stable Chronic Obstructive Pulmonary Disease: A scoping review

A decline in cognitive performance has been associated with disease severity, exacerbations rate, presence of comorbidities, and low activity level in people with chronic obstructive pulmonary disease (COPD). Participation in exercise programs appears to have neuroprotective effects and to improve cognitive performance in older people. The present work undertook a scoping review of the effects of exercise-based interventions on cognitive function in older individuals with stable COPD.

METHODS

The methodological framework for scoping review was used and electronic searches of five databases performed. Original research and observational studies published between January 2010 and December 2021, administering exercise-based interventions and cognitive function evaluation, were included.

RESULTS

Of 13 full-text manuscripts assessed for eligibility, five were allocated to analysis. Three studies administered exercise training within pulmonary outpatient rehabilitation program (PR), and one inpatient PR. The fifth study conducted a structured training intervention in which either aerobic or a combination with resistance exercises were included. Twelve cognitive function screening tools were used in the five studies included in the analysis. Results extracted were based on 245 COPD (33% female) with moderate to very-severe airflow limitation. Interventions ranged from 12 to 36 sessions. Studies reported statistically significant improvements after intervention in different cognitive function domains, such as global cognition, immediate and delayed recall ability, cognitive flexibility, verbal fluency, attention, abstract reasoning, praxis ability.

CONCLUSIONS

Exercise-based interventions improve several areas of cognitive function in patients with stable COPD. However, the magnitude of gain varies among studies, and this is possibly due to the heterogeneity of tests used. Future research is needed to validate the optimal battery of screening tests, and to support the definition of guidelines for cognitive function evaluation in COPD.

Ebselen prevents cigarette smoke-induced cognitive dysfunction in mice by preserving hippocampal synaptophysin expression

Background

Cigarette smoking (CS) is the leading cause of chronic obstructive pulmonary disease (COPD). The “spill-over” of pulmonary inflammation into the systemic circulation may damage the brain, leading to cognitive dysfunction. Cessation of CS can improve pulmonary and neurocognitive outcomes, however, its benefit on the neuroinflammatory profile remains uncertain. Here, we investigate how CS exposure impairs neurocognition and whether this can be reversed with CS cessation or an antioxidant treatment.

Methods

Male BALB/c mice were exposed to CS (9 cigarettes/day for 8 weeks) followed by 4 weeks of CS cessation. Another cohort of CS-exposed mice were co-administrated with a glutathione peroxidase mimetic, ebselen (10 mg/kg) or vehicle (5% CM-cellulose). We assessed pulmonary inflammation, spatial and working memory, and the hippocampal microglial, oxidative and synaptic profiles.

Results

CS exposure increased lung inflammation which was reduced following CS cessation. CS caused spatial and working memory impairments which were attributed to hippocampal microglial activation and suppression of synaptophysin. CS cessation did not improve memory deficits or alter microglial activation. Ebselen completely prevented the CS-induced working and spatial memory impairments, which was associated with restored synaptophysin expression without altering microglial activation.

Conclusion

We were able to model the CS-induced memory impairment and microglial activation seen in human COPD. The preventative effects of ebselen on memory impairment is likely to be dependent on a preserved synaptogenic profile. Cessation alone also appears to be insufficient in correcting the memory impairment, suggesting the importance of incorporating antioxidant therapy to help maximising the benefit of cessation.

Novel pharmacological strategies to treat cognitive dysfunction in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major incurable global health burden and currently the 3rd largest cause of death in the world, with approximately 3.23 million deaths per year. Globally, the financial burden of COPD is approximately €82 billion per year and causes substantial morbidity and mortality. Importantly, much of the disease burden and health care utilisation in COPD is associated with the management of its comorbidities and viral and bacterial-induced acute exacerbations (AECOPD). Recent clinical studies have shown that cognitive dysfunction is present in up to 60% of people with COPD, with impairments in executive function, memory, and attention, impacting on important outcomes such as quality of life, hospitalisation and survival. The high prevalence of cognitive dysfunction in COPD may also help explain the insufficient adherence to therapeutic plans and strategies, thus worsening disease progression in people with COPD. However, the mechanisms underlying the impaired neuropathology and cognition in COPD remain largely unknown. In this review, we propose that the observed pulmonary oxidative burden and inflammatory response of people with COPD 'spills over' into the systemic circulation, resulting in damage to the brain and leading to cognitive dysfunction. As such, drugs targeting the lungs and comorbidities concurrently represent an exciting and unique therapeutic opportunity to treat COPD and cognitive impairments, which may lead to the production of novel targets to prevent and reverse the debilitating and life-threatening effects of cognitive dysfunction in COPD.

Benefits of pulmonary rehabilitation in COPD patients with mild cognitive impairment - A pilot study

BACKGROUND

Cognitive impairment might interfere with the efficacy of Pulmonary Rehabilitation (PR) in Chronic Obstructive Pulmonary Disease (COPD). We aimed to identify differential responses to PR between cognitively impaired (CI) and cognitively normal (CN) COPD patients by assessing health status and exercise capacity.

METHODS

Sixty patients (FEV₁: 47 ± 15%) were classified as CI or CN according to the Montreal Cognitive Assessment (MoCA ≤25points) and completed a 3-week inpatient PR program. Cognitive function (neuropsychological battery), health-status (36-Item Short Form Survey [SF-36]), and exercise capacity (6-min walk test [6MWT], cycle-endurance test [CET]) were assessed before and after PR. Responsiveness to PR was estimated by mean change (delta-value [Δ]) and the d-Effect Size (ES).

RESULTS

Twenty-five COPD patients (42%) presented evidence of mild CI prior to PR. Both, CI and CN patients significantly improved global cognitive function, health status (the majority of SF-36 components), and exercise capacity (6MWT and cycle endurance) in response to PR. Compared to CN, CI patients did not improve SF-36 subdomains of "role emotional" and "bodily pain", and demonstrated a lower magnitude of improvement in 6MWT ([Δ]: 25 m; ES: 0.21) compared to CN ([Δ]: 46 m; ES: 0.54).

CONCLUSIONS

PR has favorable effects on global cognitive function, health status, and exercise capacity in both CI and CN COPD patients. There was no concrete evidence to indicate interference of cognitive impairment to PR effectiveness.