Verbal memory impairment in COPD: its mechanisms and clinical relevance

Exercise training influence on cognitive capacity and mental health within chronic obstructive pulmonary disease - A pilot study

Objective

Although pulmonary rehabilitation and regular exercise have improved negative emotions and cognitive capacity within cases of chronic obstructive pulmonary disease (COPD), influence by exercise training upon different cognitive and memory functions in COPD is still controversial. This investigation aimed to assess whether cognitive performance and mental health are affected by the benefits of exercise training within cases of COPD.

Materials and Methods

This pilot investigation included thirty-three patients with Global Initiative for Chronic Obstructive Lung Disease stage ≥B. Based on the subjects' rights, all included patients could choose to join either the exercise group or the control group, according to their free will. Twelve patients were assigned to receive exercise treatment over a 2-month period, while the remaining 16 patients were assigned to the control group. Cognitive capacity outcomes were measured using the Wechsler Memory Scale-III Word List Test, Stroop task, and psychomotor vigilance task (PVT). Mood states were assessed through the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI).

Results

Most cases demonstrated major improvement for BDI and BAI scorings post-60-day therapy. During PVT, the omission rate decreased, while the hit rate increased, indicating an improvement in attention performance. Furthermore, this investigation found a significant increase in immediate verbal and recognition memory for word-list test. However, no major performance shifts were found on Stroop analysis.

Conclusion

This investigation demonstrated that a 2-month exercise training program resulted in significant improvement in negative emotions, immediate memory, recognition memory, and attention.

Cognitive Function in Patients With Mild Idiopathic Pulmonary Fibrosis: A Case-Control Pilot Study

This case-control study examined cognitive function in patients with mild idiopathic pulmonary fibrosis (IPF), in comparison with controls or moderate-to-severe IPF. Ten mild IPF, 10 moderate-to-severe IPF, and 16 controls were enrolled, and performance on seven different cognitive function tests was compared in each group. IPF showed decreased cognitive function compared to controls in verbal memory, cognitive flexibility and information processing speed. As the scores were lower even in mild IPF, this study suggests that cognitive function declines early in the disease process of IPF. Thus, occupational therapy for IPF should require an assessment of cognitive function and assistance appropriate to the client's function.

Guideline Alignment and Medication Concordance in COPD

BACKGROUND

Provider adherence to clinical treatment guidelines in COPD is low. However, for patients to receive guideline-aligned care, providers not only must prescribe guideline-aligned care, but also must communicate that regimen successfully to patients to ensure medication concordance. The rate of medication concordance between patients and providers and its impact on clinical management is unknown in COPD.

RESEARCH QUESTION

To examine rates of guideline alignment and medication concordance and to identify patient-level factors that place patients at risk for these types of poor disease management outcomes.

STUDY DESIGN AND METHODS

This study was a secondary data analysis of the Medication Adherence Research in COPD study (2017-2023). Participants were categorized into 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage. Medication regimens were classified as aligned or nonaligned with 2017 GOLD guidelines. Nonaligned regimens were stratified further into overuse and underuse categories. Medication concordance between provider-reported and participant-reported regimens was determined. Factors associated with guideline alignment and medication concordance were evaluated using logistic regression.

RESULTS

Of 191 participants, 51% of provider-reported regimens were guideline aligned, with 86% of nonaligned regimens reflecting overuse with an inhaled corticosteroid (ICS). Thirty-eight percent of participants reported different regimens than their providers, of which > 80% reflected participants not reporting medications their providers reported prescribing. Participants did not report long-acting muscarinic antagonists and long-acting beta-agonists at similar rates as ICSs. Greater symptom burden and absence of a pulmonologist on the care team were associated with both guideline misalignment and medication discordance. Cognitive impairment and Black race additionally were associated with medication discordance.

INTERPRETATION

Guideline misalignment and medication discordance were common and were driven by overuse of ICSs and unreported medications, respectively. The patient-level factors associated with medication discordance highlight the importance of improving patient-provider communication to improve clinical management in COPD.

Association between cognitive decline and activities of daily living decline in patients undergoing long-term oxygen therapy: a prospective observational pilot study

PURPOSE

Patients undergoing long-term oxygen therapy (LTOT) are predisposed to progressive cognitive decline; however, the association between cognitive decline progression and activities of daily living (ADL) decline has not been described. We aimed to describe the association between cognitive decline progression and ADL decline in patients undergoing LTOT.

MATERIALS AND METHODS

In this prospective observational pilot study, data were collected at baseline and 1-year following the ambulatory recruitment of patients in the Department of Respiratory Medicine at the National Hospital Organization Nishiniigata Chuo Hospital. We recruited 96 patients with chronic respiratory disease undergoing LTOT, and 55 patients who completed a 1-year follow-up were finally included.

RESULTS

Multivariate logistic regression analysis revealed that Montreal Cognitive Assessment score reduction (a measure of cognitive decline) was associated with Barthel index score reduction (a measure of ADL) at 1-year follow-up (odds ratio: 3.98; 95% confidence interval: 1.16 - 13.69; p = 0.02).

CONCLUSION

A progression of cognitive decline in patients undergoing LTOT may affect ADL decline. An early detection of cognitive decline in patients undergoing LTOT is essential for ADL maintenance in rehabilitation practice.IMPLICATIONS FOR REHABILITATIONPatients undergoing long-term oxygen therapy (LTOT) present with progressive cognitive decline.Cognitive decline progression is associated with a decline in activities of daily living in patients undergoing LTOT.A periodic cognitive assessment is important in rehabilitation practice for the early detection of progressive cognitive decline in patients undergoing LTOT.

The Association Between Cognitive Functions and Psychological Factors in Patients with Severe COPD

Purpose

Patients with COPD experience anxiety, depression, and stress more frequently than in the age and gender-matched general population. This cross-sectional study aimed to examine the relationship between cognitive functions and the psychological factors of anxiety, depression and stress among patients with COPD.

Patients and Methods

Between January 2021 and January 2023, patients with severe COPD were recruited, along with age-matched controls. Participants completed the Hospital Anxiety and Depression Scale (HADS) and the Perceived Stress Scale (PSS). The Montreal Cognitive Assessment (MoCA), a continuous reaction time test (CRT), and a driving simulator were used to assess cognitive impairment. Hierarchical multiple linear regression analyses were used to explain the variance of the correlations.

Results

In total, 80 patients (mean age = 64yrs) and 22 controls (mean age = 61yrs) participated in the study. Patients reported significantly higher levels of psychological symptoms compared to the controls (p ≤ 0.001). We found no differences in anxiety (p = 0.31), depression (p = 0.66) and stress (p = 0.37) between patients with and without cognitive impairment. However, stress showed to be a significant predictor of decreased attention (higher stress score resulted in decreasing CRT-index, indication a reduced stability in reaction time) (p = 0.02). Psychological factors did not explain additional variance in cognitive functions beyond sociodemographic factors such as age and sex.

Conclusion

Psychological symptom levels are higher in COPD than controls and perceived stress among patients with COPD appears to be associated with decreased attention. However, psychological factors in general did not appear to contribute to the variance in cognitive functions beyond sociodemographic, physical, and self-perceived symptoms.

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.

Impact of Coexisting Dementia on Inpatient Outcomes for Patients Admitted with a COPD Exacerbation

Purpose

People with COPD are at a higher risk of cognitive dysfunction than the general population. However, the additional impact of dementia amongst such patients is not well understood, particularly in those admitted with a COPD exacerbation. We assessed the impact of coexisting dementia on inpatient mortality and length of stay (LOS) in patients admitted to hospital with a COPD exacerbation, using the United States based National Inpatient Sample database.

Patients and Methods

Patients aged over 40 years and hospitalised with a primary diagnosis of COPD exacerbation from 2011 to 2015 were included. Cases were grouped into patients with and without dementia. Multivariable logistic regression analysis, stratified by age, was used to assess risk of inpatient deaths. Cox regression was carried out to compare death rates and competing risk analysis gave estimates of discharge rates with time to death a competing variable.

Results

A total of 576,381 patients were included into the analysis, of which 35,372 (6.1%) had co-existent dementia. There were 6413 (1.1%) deaths recorded. The odds of inpatient death were significantly greater in younger patients with dementia (41–64 years) [OR (95% CI) dementia vs without: 1.75 (1.04–2.92), p=0.03]. Cases with dementia also had a higher inpatient mortality rate in the first 4 days [HR (95% CI) dementia vs without: 1.23 (1.08–1.41), p=0.002] and a longer LOS [sub-hazard ratio (95% CI) dementia vs without: 0.93 (0.92–0.94), p<0.001].

Conclusion

Dementia as a comorbidity is associated with worse outcomes based on inpatient deaths and LOS in patients admitted with COPD exacerbations.

Examining the possible causal relationship between lung function, COPD and Alzheimer's disease: a Mendelian randomisation study

Rationale

Large retrospective case-control studies have reported an association between chronic obstructive pulmonary disease (COPD), reduced lung function and an increased risk of Alzheimer’s disease. However, it remains unclear if these diseases are causally linked, or due to shared risk factors. Conventional observational epidemiology suffers from unmeasured confounding and reverse causation. Additional analyses addressing causality are required.

Objectives

To examine a causal relationship between COPD, lung function and Alzheimer’s disease.

Methods

Using two-sample Mendelian randomisation, we used single nucleotide polymorphisms (SNPs) identified in a genome wide association study (GWAS) for lung function as instrumental variables (exposure). Additionally, we used SNPs discovered in a GWAS for COPD in those with moderate to very severe obstruction. The effect of these SNPs on Alzheimer’s disease (outcome) was taken from a GWAS based on a sample of 24 807 patients and 55 058 controls.

Results

We found minimal evidence for an effect of either lung function (OR: 1.02 per SD; 95% CI 0.91 to 1.13; p value 0.68) or liability for COPD on Alzheimer’s disease (OR: 0.97 per SD; 95% CI 0.92 to 1.03; p value 0.40).

Conclusion

Neither reduced lung function nor liability COPD are likely to be causally associated with an increased risk of Alzheimer’s, any observed association is likely due to unmeasured confounding. Scientific attention and health prevention policy may be better focused on overlapping risk factors, rather than attempts to reduce risk of Alzheimer’s disease by targeting impaired lung function or COPD directly.

Physiological and neurochemical adaptations following abrupt termination of chronic hypercapnia in goats

Chronic hypercapnia (CH) is a hallmark of respiratory diseases such as chronic obstructive pulmonary disease. In such patients, mechanical ventilation is often used to restore normal blood-gas homeostasis. However, little is known regarding physiological changes and neuroplasticity within physiological control networks after termination of CH. Utilizing our goat model of increased inspired CO₂-induced CH, we determined whether termination of CH elicits time-dependent physiological and neurochemical changes within brain stem sites of physiological control. Thirty days of CH increased [Formula: see text] (+15 mmHg) and steady-state ventilation (SS V̇i; 283% of control). Within 24 h after terminating CH, SS V̇i, blood gases, arterial [H⁺], and most physiological measurements returned to control. However, the acute ventilatory chemoreflex (ΔV̇i/Δ[H⁺]) was greater than control, and measured SS V̇i exceeded ventilation predicted by arterial [H⁺] and ΔV̇i/Δ[H⁺]. Potentially contributing to these differences were increased excitatory neuromodulators serotonin and norepinephrine in the nucleus tractus solitarius, which contrasts with minimal changes observed at 24 h and 30 days of hypercapnia. Similarly, there were minimal changes found in markers of neuroinflammation and glutamate receptor-dependent neuroplasticity upon termination of CH, which were previously increased following 24 h of hypercapnia. Thus, following termination of CH: 1) ventilatory, renal, and other physiological functions rapidly return to control; 2) neuroplasticity within the ventilatory control network may contribute to the difference between measured vs. predicted ventilation and the elevation in the acute ventilatory [H⁺] chemoreflex; and 3) neuroplasticity is fundamentally distinct from acclimatization to CH.NEW & NOTEWORTHY In healthy adult goats, steady-state ventilation and most physiological measures return to control within 24 h after termination of chronic hypercapnia (CH). However, the acute [H⁺] chemoreflex is increased, and measured ventilation exceeds predicted ventilation. At 24 h of recovery, excitatory neuromodulators are above control, but other measured markers of neuroplasticity are unchanged from control. Our data suggest that CH elicits persistent physiological and neurochemical changes for up to 24 h after termination of CH.

From Mild Cognitive Impairment (MCI) to Dementia in Chronic Obstructive Pulmonary Disease. Implications for Clinical Practice and Disease Management: A Mini-Review

Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease characterized by partially irreversible chronic airflow limitation. Current literature highlights that COPD patients also have an increased risk to develop Mild Cognitive Impairment (MCI) and dementia. Chronic patients with cognitive impairment experience a worsening of health-related quality of life, mainly because it could affect treatment self-management, medication adherence and personal independence. Moreover, they also report high levels of anxiety and depression, which are associated with disease severity, poor quality of life, poor adherence to rehabilitation programs and difficulties in self-management. In current literature, there is a lack of studies describing simultaneously the associations between cognitive impairment, dysfunctional psychosocial factors, self-management abilities and their impact on pharmacological/non-pharmacological adherence. Therefore, the aim of the present short review is to describe the implications of cognitive impairment and psychosocial factors for clinical practice and disease management in COPD patients. Due to the interaction of these factors on adherence to rehabilitation programs, self-management and rehabilitation completion, future research should investigate simultaneously the role of all these different aspects to individuate a specific clinical approach that might include specific screening tools to evaluate cognitive impairment and psychosocial difficulties. A timely specific evaluation, within an interdisciplinary approach, could help to implement a more individualized and personalized treatment.

Risk Factors for Postural and Functional Balance Impairment in Patients with Chronic Obstructive Pulmonary Disease

Reduced balance function has been observed during balance challenging conditions in the chronic obstructive pulmonary disease (COPD) population and is associated with an increased risk of falls. This study aimed to examine postural balance during quiet standing with eyes open and functional balance in a heterogeneous group of COPD and non-COPD (control) subjects, and to identify risk factors underlying balance impairment using a large panel of methods. In COPD and control subjects, who were mostly overweight and sedentary, postural and functional balance were assessed using center-of-pressure displacement in anterior-posterior (AP) and medio-lateral (ML) directions, and the Berg Balance Scale (BBS), respectively. COPD showed 23% greater AP sway velocity (p = 0.049). The presence of oxygen therapy, fat mass, reduced neurocognitive function, and the presence of (pre)diabetes explained 71% of the variation in postural balance in COPD. Transcutaneous oxygen saturation, a history of exacerbation, and gait speed explained 83% of the variation in functional balance in COPD. Neurocognitive dysfunction was the main risk factor for postural balance impairment in the control group. This suggests that specific phenotypes of COPD patients can be identified based on their type of balance impairment.

Midbrain and cerebral inflammatory and glutamatergic adaptations during chronic hypercapnia in goats

Cognitive impairment is associated with multiple human diseases that have in common chronic hypercapnia. However, the mechanisms leading to chronic hypercapnia-induced cognitive decline are not known. We have previously shown chronic hypercapnia through exposure to increased inspired CO₂ (6% InCO₂) in conscious goats caused an immediate (within hours) and sustained decline in cognitive performance during a shape discrimination test. Herein, within the same goats, we assessed markers of neuroinflammation and glutamate receptor expression/phosphorylation within CNS regions important for cognitive function following 24 hours (h) or 30 days (d) of chronic hypercapnia. Within 24 h, chronic hypercapnia increased expression of the inflammatory cytokine IL-1β in the orbitofrontal cortex and medial prefrontal cortex, but at 30d IL-1β levels were not different relative to time-matched goats exposed to room-air. Additionally, Iba1 expression (a marker of microglial activation) was unaltered by chronic hypercapnia in all regions tested. Finally, levels of the total and phosphorylated AMPA receptor subunit GluR₂ were reduced within the hippocampus at both 24 h and 30 d of hypercapnia, and reduced following 30 d within the anterior insular cortex. These data suggest that chronic hypercapnia leads to CNS site-dependent acute inflammatory responses and shifts in select glutamate receptor expression/phosphorylation in brain regions contributing to cognitive function. Such changes may be indicative of alterations in glutamatergic receptor-mediated signaling and neuronal dysfunction that contribute to declines in cognitive function associated with human diseases defined or marked by chronic CO₂ retention.

Disruption of white matter connectivity in chronic obstructive pulmonary disease

Background

Mild cognitive impairment is a common systemic manifestation of chronic obstructive pulmonary disease (COPD). However, its pathophysiological origins are not understood. Since, cognitive function relies on efficient communication between distributed cortical and subcortical regions, we investigated whether people with COPD have disruption in white matter connectivity.

Methods

Structural networks were constructed for 30 COPD patients (aged 54–84 years, 57% male, FEV₁ 52.5% pred.) and 23 controls (aged 51–81 years, 48% Male). Networks comprised 90 grey matter regions (nodes) interconnected by white mater fibre tracts traced using deterministic tractography (edges). Edges were weighted by the number of streamlines adjusted for a) streamline length and b) end-node volume. White matter connectivity was quantified using global and nodal graph metrics which characterised the networks connection density, connection strength, segregation, integration, nodal influence and small-worldness. Between-group differences in white matter connectivity and within-group associations with cognitive function and disease severity were tested.

Results

COPD patients’ brain networks had significantly lower global connection strength (p = 0.03) and connection density (p = 0.04). There was a trend towards COPD patients having a reduction in nodal connection density and connection strength across the majority of network nodes but this only reached significance for connection density in the right superior temporal gyrus (p = 0.02) and did not survive correction for end-node volume. There were no other significant global or nodal network differences or within-group associations with disease severity or cognitive function.

Conclusion

COPD brain networks show evidence of damage compared to controls with a reduced number and strength of connections. This loss of connectivity was not sufficient to disrupt the overall efficiency of network organisation, suggesting that it has redundant capacity that makes it resilient to damage, which may explain why cognitive dysfunction is not severe. This might also explain why no direct relationships could be found with cognitive measures. Smoking and hypertension are known to have deleterious effects on the brain. These confounding effects could not be excluded.

Contributions of cardiovascular risk and smoking to chronic obstructive pulmonary disease (COPD)-related changes in brain structure and function

Background

Brain damage and cardiovascular disease are extra-pulmonary manifestations of chronic obstructive pulmonary disease (COPD). Cardiovascular risk factors and smoking are contributors to neurodegeneration. This study investigates whether there is a specific, COPD-related deterioration in brain structure and function independent of cardiovascular risk factors and smoking.

Materials and methods

Neuroimaging and clinical markers of brain structure (micro- and macro-) and function (cognitive function and mood) were compared between 27 stable COPD patients (age: 63.0±9.1 years, 59.3% male, forced expiratory volume in 1 second [FEV1]: 58.1±18.0% pred.) and 23 non-COPD controls with >10 pack years smoking (age: 66.6±7.5 years, 52.2% male, FEV1: 100.6±19.1% pred.). Clinical relationships and group interactions with brain structure were also tested. All statistical analyses included correction for cardiovascular risk factors, smoking, and aortic stiffness.

Results

COPD patients had significantly worse cognitive function (p=0.011), lower mood (p=0.046), and greater gray matter atrophy (p=0.020). In COPD patients, lower mood was associated with markers of white matter (WM) microstructural damage (p<0.001), and lower lung function (FEV1/forced vital capacity and FEV1) with markers of both WM macro (p=0.047) and microstructural damage (p=0.028).

Conclusion

COPD is associated with both structural (gray matter atrophy) and functional (worse cognitive function and mood) brain changes that cannot be explained by measures of cardiovascular risk, aortic stiffness, or smoking history alone. These results have important implications to guide the development of new interventions to prevent or delay progression of neuropsychiatric comorbidities in COPD. Relationships found between mood and microstructural abnormalities suggest that in COPD, anxiety, and depression may occur secondary to WM damage. This could be used to better understand disabling symptoms such as breathlessness, improve health status, and reduce hospital admissions.

Assessment of Cognitive Impairment in Patients with Chronic Obstructive Pulmonary Disease Using the Rapid Cognitive Screen

OBJECTIVES

To determine the prevalence of cognitive impairment in chronic obstructive pulmonary disease (COPD) patients using the Rapid Cognitive Screen (RCS).

DESIGN

Cross sectional study.

PARTICIPANTS

A total of 106 men and women with COPD 50 years of age or older.

SETTING

Pulmonary ambulatory clinic in a tertiary academic center in St. Louis, Missouri, USA.

MEASUREMENTS

We enrolled patients with COPD who completed the RCS tool. Patients were classified as having normal cognition, mild cognitive impairment (MCI), or dementia if they scored ≥ 8, 6-7, or ≤ 5, respectively. The prevalence of each category was measured, and patients' baseline characteristics were compared.

RESULTS

One hundred and six patients completed the RCS. Of those, 36 (33.9%) patients scored ≤ 5 on the RCS, 33 (31.1%) scored 6 or 7, and 37 (34.9%) scored ≥ 8. The prevalence of dementia, MCI, and normal cognition were 33.9%, 31.1%, and 34.9%, respectively. Baseline lung function was not different between patients with normal cognition and those with abnormal cognition (FEV1 1.53 ± 0.39 vs 1.45 ± 0.32 L). In patients with abnormal cognition, there was no difference in patients' characteristics between patients with MCI or dementia.

CONCLUSION

Cognitive impairment is highly prevalent in patients with COPD. RCS successfully identified cognitive impairment in COPD. We recommend performing RCS in patients with COPD routinely.

Visual rating assessment of cerebral atrophy and its relationship with cognitive function in chronic obstructive pulmonary disease

Introduction

Widespread white matter damage and cognitive impairment have been demonstrated in chronic obstructive pulmonary disease (COPD). However, it remains unclear if brain atrophy is a global phenomenon or if specific subregions are differentially affected. The aims of this study are, first, to test a simple, validated visual analogue grading technique. Second, we hypothesised that frontal regions of the brains of patients with COPD will show greater signs of atrophy compared with control subjects. Third, any localised regions of atrophy would correlate with components of cognitive performance. Finally, the severity of cerebral atrophy would be associated with measures of respiratory disease severity.

Methods

We used a simple, validated visual analogue grading technique to assess the degree of regional atrophy in multiple brain regions from cerebral MR images in patients with stable non-hypoxaemic COPD (n=25) and age-matched control subjects (n=25). We also explored correlations between regional brain atrophy with demographics, cognitive performance measures and disease severity. Measures of cognitive performance focused on executive function, working memory, verbal memory, overall memory and processing speed. Measures of disease severity include lung function, gas exchange, health status and breathlessness questionnaires.

Results

The visual grading scale found that patients with COPD had significantly greater frontal atrophy than control subjects (p=0.02), independent of smoking history, comorbid depression or anxiety. Cognitive function was significantly worse in the COPD group for executive function (p<0.001), working memory (p=0.02), verbal memory (p=0.03) and processing speed (p=0.001). Group differences in atrophy did not appear to account for differences in cognitive function. We were unable to identify meaningful correlations between regional atrophy and disease severity or cognitive function.

Conclusion

Further work is needed to identify causative mechanisms behind unexplained structural brain changes in COPD.

Ventilatory and integrated physiological responses to chronic hypercapnia in goats

KEY POINTS

Chronic hypercapnia per se has distinct effects on the mechanisms regulating steady-state ventilation and the CO₂ /H⁺ chemoreflex. Chronic hypercapnia leads to sustained hyperpnoea that exceeds predicted ventilation based upon the CO₂ /H⁺ chemoreflex. There is an integrative ventilatory, cardiovascular and metabolic physiological response to chronic hypercapnia. Chronic hypercapnia leads to deterioration of cognitive function.

ABSTRACT

Respiratory diseases such as chronic obstructive pulmonary disease (COPD) often lead to chronic hypercapnia which may exacerbate progression of the disease, increase risk of mortality and contribute to comorbidities such as cognitive dysfunction. Determining the contribution of hypercapnia per se to adaptations in ventilation and cognitive dysfunction within this patient population is complicated by the presence of multiple comorbidities. Herein, we sought to determine the role of chronic hypercapnia per se on the temporal pattern of ventilation and the ventilatory CO₂ /H⁺ chemoreflex by exposing healthy goats to either room air or an elevated inspired CO₂ (InCO₂ ) of 6% for 30 days. A second objective was to determine whether chronic hypercapnia per se contributes to cognitive dysfunction. During 30 days of exposure to 6% InCO₂ , steady-state (SS) ventilation ( V ̇ _I ) initially increased to 335% of control, and then within 1-5 days decreased and stabilized at ∼230% of control. There was an initial respiratory acidosis that was partially mitigated over time due to increased arterial [HCO₃ ^- ]. There was a transient decrease in the ventilatory CO₂ /H⁺ chemoreflex, followed by return to pre-exposure levels. The SS V ̇ _I during chronic hypercapnia was greater than predicted from the acute CO₂ /H⁺ chemoreflex, suggesting separate mechanisms regulating SS V ̇ _I and the chemoreflex. Finally, as assessed by a shape discrimination test, we found a sustained decrease in cognitive function during chronic hypercapnia. We conclude that chronic hypercapnia per se results in: (1) a disconnect between SS V ̇ _I and the CO₂ /H⁺ chemoreflex, and (2) deterioration of cognitive function.

Airflow obstruction, cognitive function and mortality in a US national cohort: NHANES-III

OBJECTIVE

To test the hypothesis that cognitive impairment increases mortality independent of airflow obstruction.

MATERIALS AND METHODS

In 1988-1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured forced expiratory volume in the first second (FEV1) and the forced vital capacity (FVC) and selected items on cognitive function with mortality follow-up. For this survival analysis 4365 persons aged 60 and over with complete data formed the analytic sample.

RESULTS

The FEV1/FVC less than the lower limit of predicted ratio (LLP) defined airflow obstruction and Composite Cognitive Function Score (CCF) ≤4, cognitive impairment. The percentage who died during follow up was 67% among those with neither FEV1/FVC < LLP nor CCF ≤4, 82% with FEV1/FVC < LLP only, 85% with CCF score ≤4 only and 93% with both FEV1/FVC LLP and CCF score ≤4 (P < .001). Weighted Cox proportional hazards regression revealed an increased hazard ratio (HR) in persons with FEV1/FVC <LLP only and in persons with CCF ≤4 only, respectively, compared with persons with neither. FEV1/FVC ratio < LLP remained a significant predictor of mortality with an interaction between FEV1/FVC ratio < LLP and CCF ≤4 (P = .051).

CONCLUSION

Elderly persons with either airflow obstruction or cognitive impairment or both had increased all-cause mortality when compared to those with neither after adjusting for confounders. However, cognitive impairment was not a predictor of increased mortality independent of airflow obstruction.

Clinical effects of cognitive impairment in patients with chronic obstructive pulmonary disease

The aim of this study was to evaluate the clinical effects of cognitive impairment in patients with chronic obstructive pulmonary disease (COPD). A total of 91 patients with stable moderate to very severe COPD were included in this study. Cognitive functions of the patients were evaluated using the mini-mental state examination (MMSE) tool and clock-drawing test. The Brody’s Instrumental Activities of Daily Living (IADL) Questionnaire; COPD assessment test (CAT); body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE); and Charlson comorbidity index were assessed. The patients were divided into two groups as those who were diagnosed with cognitive impairment (group 1, n = 16) and those with normal cognitive functions (group 2, n = 75). Group 1 had a lower arterial partial pressure of oxygen , shorter 6-min walking distance, and higher arterial partial pressure of carbon dioxide (PaCO₂) than group 2 (p = 0.01, p = 0.024, p = 0.018, respectively). In group 1, the IADL score was lower, and CAT and BODE scores were higher than group 2 (p = 0.002, p = 0.037, p = 0.012, respectively). When we considered all the patients, there was an independent correlation between the IADL score and MMSE score (p = 0.03). This study revealed that COPD patients with cognitive impairment may have more hypoxemia and limited activities of daily living.

Computerized screening for cognitive impairment in patients with COPD

Purpose

COPD is associated with cognitive impairment. These impairments should be diagnosed, but due to time- and budget-reasons, they are often not investigated. The aim of this study is to examine the viability of a brief computerized cognitive test battery, Central Nervous System Vital Signs (CNSVS), in COPD patients.

Patients and methods

Patients with COPD referred to tertiary pulmonary rehabilitation were included. Cognitive functioning of patients was assessed with CNSVS before pulmonary rehabilitation and compared with age-corrected CNSVS norms. CNSVS is a 30 minute computerized test battery that includes tests of verbal and visual memory, psychomotor speed, processing speed, cognitive flexibility, complex attention, executive functioning, and reaction time.

Results

CNSVS was fully completed by 205 (93.2%, 105 females, 100 males) of the total group of patients (n=220, 116 females, 104 males). Z-tests showed that COPD patients performed significantly worse than the norms on all CNSVS cognitive domains. Slightly more than half of the patients (51.8%) had impaired functioning on 1 or more cognitive domains. Patients without computer experience performed significantly worse on CNSVS than patients using the computer frequently.

Conclusion

The completion rate of CNSVS was high and cognitive dysfunctions measured with this screening were similar to the results found in prior research, including paper and pen cognitive tests. These results support the viability of this brief computerized cognitive screening in COPD patients, that may lead to better care for these patients. Cognitive performance of patients with little computer experience should be interpreted carefully. Future research on this issue is needed.

The impact of cognitive impairment on self-management in chronic obstructive pulmonary disease: A systematic review

OBJECTIVE

To determine the characteristics of persons with cognitive impairment being able to self-manage in chronic obstructive pulmonary disease (COPD).

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance this systematic review examined all studies in English from 1st January 2000 to 20 February 2016, describing the relationship between cognition and COPD self-management domains in older community dwelling persons with dementia or cognitive impairment.

RESULTS

Of 4474 studies identified, thirteen studies were eligible for inclusion. No studies differentiated populations into recognized dementia subtypes. Study aims were variable; most (n = 7) examined inhaler competency alone. Studies identified a link between worsening cognition and the need for assistance in activities of daily living. Only one study evaluated the impact of cognition on overall self-management and found no association between cognitive impairment and self-rated self-management. Mild degrees of cognitive impairment were associated with reduced symptom recall. Cognitive impairment in COPD was associated with high degrees of inhaler incompetency. Basic cognitive screening tests were able to predict inhaler incompetence with reduced overall cognitive function, dyspraxia, and/or executive function identified as predictors of incompetency.

CONCLUSIONS

Multiple measures of disability consistently demonstrated that cognitive impairment in COPD significantly increased the need for assistance in many aspects of daily living, treatment adherence, and effective self-management. Given the nature of neuropsychological deficits seen in COPD, dedicated screening tools are required. Future research should investigate the impact of cognitive dysfunction in COPD and identify how to support those that lack capacity to self-manage.

Cognitive impairment in COPD: should cognitive evaluation be part of respiratory assessment?

Cognitive impairment is highly prevalent in patients with COPD and demonstrates multiple detrimental effects on many aspects of patient state and therapeutic outcomes. It is attributed to several overlapping pathophysiological factors, with the most common being the low level of oxygen saturation due to respiratory insufficiency. Despite the impact of cognitive impairment on clinical outcomes, the screening for coexisting cognitive deficits which may interfere with the successful progress of respiratory treatment is yet neglected. There is a special consideration that cognitive deficits should be taken into account when developing respiratory therapy plans. Cognitively impaired patients are likely to require more support and have need of an individualised respiratory care plan which can also be beneficial for their cognitive deficits. Pulmonary rehabilitation as a multidisciplinary approach could be prioritised for COPD patients with cognitive impairment.

EDUCATIONAL AIMS

To illustrate the common signs of cognitive impairment and define potential associations between lung and cognitive dysfunction.To illustrate the potential influence of cognitive deficits on the optimal progress of respiratory therapy.To illustrate the importance of cognitive evaluation as part of a comprehensive clinical assessment for patients suspected of suffering cognitive impairment.

Cognitive status among patients with chronic obstructive pulmonary disease

PURPOSE

We investigated the association between cognitive impairment and chronic obstructive pulmonary disease (COPD), taking into account demographic and clinical variables evaluated during routine practice.

PATIENTS AND METHODS

We performed a post hoc analysis of a cross-sectional study that included subjects with stable COPD. Sociodemographic and clinical information was recorded using the Body mass index, airflow Obstruction, Dyspnea and Exacerbations index and the Charlson comorbidity index. Cognitive performance was studied by the mini-mental state examination, with a score less than 27 indicating clinical impairment. Depressive symptoms, physical activity, and quality of life (EuroQoL-5 dimensions and COPD Assessment Test) were also evaluated.

RESULTS

The analysis included 940 subjects. The prevalence of cognitive impairment was 39.4%. Multivariate logistic regression models revealed that cognitive impairment was associated with educational level (odds ratio [OR] =0.096, 95% confidence interval [CI] =0.011-0.447) and poorer quality of life measured by the EuroQoL-5 dimensions social tariff (OR =0.967, 95% CI =0.950-0.983). When questionnaires were not included in the analysis, cognitive impairment was associated with educational level (OR =0.063, 95% CI =0.010-0.934), number of exacerbations (OR =11.070, 95% CI =1.450-84.534), Body mass index, airflow Obstruction, Dyspnea and Exacerbations index score (OR =1.261, 95% CI =1.049-1.515), and the Charlson comorbidity index (OR =1.412, 95% CI =1.118-1.783).

CONCLUSION

Cognitive impairment is common in COPD and is associated with low educational level, higher disease severity, and increased comorbidity. This could have therapeutic implications for this population.

Driving performance in patients with chronic obstructive lung disease, interstitial lung disease and healthy controls: a crossover intervention study

Introduction

Cognitive deficits in patients suffering from chronic obstructive pulmonary disease (COPD) have been described and hypoxaemia has been addressed as a possible cause. Cognitive functions in patients with interstitial lung disease (ILD) are not well studied. These patients are taking part in everyday traffic, but little is known regarding their driving performance. This study was conducted to determine the driving performance in patients with COPD and ILD, respectively compared to healthy controls using a driving simulator. Additionally, the effect of oxygen supply was addressed.

Methods

16 patients with COPD (8 receivers and 8 non-receivers of long-term oxygen therapy (LTOT)), 8 patients with ILD (consisting of idiopathic interstitial pneumonias) and 8 healthy controls were tested in a driving simulator. Each test lasted 45 min. In the oxygen intervention part of the study the patients were randomised to receive oxygen therapy in the first or second test and acted as their own controls.

Results

Patients with COPD had significantly impaired driving performance when comparing SD from the centre of the road and number of off-road events to controls. Patients with COPD receiving LTOT performed significantly worse than those not receiving LTOT when comparing SD and worse than the patients with ILD when comparing SD and off-road events. Patients with ILD performed similarly to controls (SD: LTOT 2.39*; no LTOT 0.69*; ILD 0.37; controls 0.36; *p<0.05. Off-road: LTOT 226.67*; no LTOT 78.92*; ILD 40.00; controls 25.78; *p<0.05). Oxygen therapy had no effect on driving performance.

Conclusions

Patients with ILD performed similarly to controls in the driving simulator, whereas patients with COPD showed decreased driving performance, especially those receiving LTOT. Doctors should be aware of this when renewing the driving license of patients with COPD. Oxygen therapy showed no effect on driving performance.

Trial registration number

NCT02125916

Does COPD have a clinically relevant impact on hearing loss? A retrospective matched cohort study with selection of patients diagnosed with COPD

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) as a multisystemic disease has a measurable and biologically explainable impact on the auditory function detectable in the laboratory. This study tries to clarify if COPD is also a significant and clinically relevant risk factor for hearing impairment detectable in the general practice setting.

DESIGN

Retrospective matched cohort study with selection of patients diagnosed with COPD.

SETTING

12 general practices in Lower Austria.

PARTICIPANTS

Consecutive patients >35 years with a diagnosis of COPD who consulted 1 of 12 single-handed GPs in 2009 and 2010 were asked to participate. Those who agreed were individually 1:1 matched with controls according to age, sex, hypertension, diabetes, coronary heart disease and chronic heart failure.

MAIN OUTCOME MEASURES

Sensorineural hearing impairment as assessed by pure tone audiometry, answers of three questions concerning a self-perceived hearing problem, application of the whispered voice test and the score of the Hearing Inventory for the Elderly, Screening Version (HHIE-S).

RESULTS

194 patients (97 pairs of 194 cases and controls) with a mean age of 65.5 (SD 10.2) were tested. Univariate conditional logistic regression resulted in significant differences in the mean bone conduction hearing loss and in the total score of HHIE-S, in the multiple conditional regression model, only smoking (p<0.0001) remained significant.

CONCLUSIONS

The results of this study do not support the hypothesis that there is an association between COPD and hearing impairment which, if found, would have allowed better management of patients with COPD.

Assessment of cognitive impairment in long-term oxygen therapy-dependent COPD patients

BACKGROUND

A number of studies have shown that COPD, particularly in its later and more severe stages, is associated with various cognitive deficits. Thus, the primary goal of the present study was to elucidate the extent of cognitive impairment in patients with long-term oxygen therapy-dependent (LTOTD) COPD. In addition, this study aimed to determine the effectiveness of two cognitive screening tests, the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA), for COPD patients and the ability of oxygen therapy to mitigate COPD-related deficits in cognitive function.

METHODS

The present study enrolled 45 subjects: 24 nonuser and 21 regular-user LTOTD-COPD patients. All subjects had a similar grade of education, and there were no significant differences regarding age or sex. The MoCA (cutoff: <26 points) and MMSE (cutoff: ≤24 points) scores were compared between these two groups.

RESULTS

The nonuser LTOTD-COPD group had a significantly lower MoCA score than that of the regular-user LTOTD-COPD group (19.38±2.99 vs 21.68±2.14, respectively) as well as a significantly lower MMSE score. Moreover, the absence of supplemental oxygen therapy increased the risk of cognitive impairment (MoCA, P=0.007 and MMSE, P=0.014), and the MoCA and MMSE scores significantly correlated with the number of emergency admissions and the number of hospitalizations in the last year.

CONCLUSION

In the present study, the nonuser LTOTD-COPD group exhibited a significant decrease in cognitive status compared with the regular-user LTOTD-COPD group. This suggests that the assessment of cognitive function in nonuser LTOTD-COPD patients and the use of protective strategies, such as continuous supplemental oxygen treatment, should be considered during the management of COPD in this population. In addition, the MoCA score was superior to the MMSE score for the determination of cognitive impairment in the nonuser LTOTD-COPD patients.

Chronic obstructive pulmonary disease and cerebrovascular disease: A comprehensive review

Along with the aging population, the public health burden of cerebrovascular disease is increasing. Cerebral small vessel disease and accumulation of brain pathology associate with cognitive decline and can lead to clinical outcomes, such as stroke and dementia. Chronic Obstructive Pulmonary Disease (COPD) is a common respiratory disease among elderly. The quality of life and prognosis of patients with COPD is greatly determined by the presence of comorbidities including stroke and cognitive impairment. Despite the clinical relevance of cerebral small vessel disease, stroke and (vascular) cognitive impairment in patients with COPD, literature is scarce and underlying mechanisms are unknown. The aim of the present review is therefore to summarize current scientific knowledge, to provide a better understanding of the interplay between COPD and the aging brain and to define remaining knowledge gaps. This narrative review article 1) overviews the epidemiology of cerebral small vessel disease, stroke and cognitive impairment in patients with COPD; 2) discusses potential underlying mechanisms including aging, smoking, systemic inflammation, vasculopathy, hypoxia and genetic susceptibility; and 3) highlights areas requiring further research.

Cognitive impairment in COPD: a systematic review

The objectives of this study were to characterize and clarify the relationships between the various cognitive domains affected in COPD patients and the disease itself, as well as to determine the prevalence of impairment in the various cognitive domains in such patients. To that end, we performed a systematic review using the following databases: PubMed, Scopus, and ScienceDirect. We included articles that provided information on cognitive impairment in COPD patients. The review of the findings of the articles showed a significant relationship between COPD and cognitive impairment. The most widely studied cognitive domains are memory and attention. Verbal memory and learning constitute the second most commonly impaired cognitive domain in patients with COPD. The prevalence of impairment in visuospatial memory and intermediate visual memory is 26.9% and 19.2%, respectively. We found that cognitive impairment is associated with the profile of COPD severity and its comorbidities. The articles reviewed demonstrated that there is considerable impairment of the cognitive domains memory and attention in patients with COPD. Future studies should address impairments in different cognitive domains according to the disease stage in patients with COPD.

Characteristics of patients with COPD newly prescribed a long-acting bronchodilator: a retrospective cohort study

Introduction

This study aimed to characterize patients with chronic obstructive pulmonary disease (COPD) newly prescribed a long-acting bronchodilator (LABD), and to assess changes in medication over 24 months.

Methods

A cohort of patients with COPD aged ≥40 years newly prescribed an LABD between January 1, 2007 and December 31, 2009 were identified from the Truven Marketscan^® Commercial Database (Truven Health Analytics, Ann Arbor, MI, USA) and followed for 24 months. Inclusion criteria included no prior prescription for an LABD or inhaled corticosteroids for 12 months prior to the LABD index date (baseline). Patient characteristics were examined. As LABDs were mainly long-acting muscarinic antagonists (LAMAs), additions, switches, discontinuation, adherence to (medication possession ratio), and persistence (proportion of days covered) with LAMA monotherapy were assessed for 24 months following the index date. Adherence and persistence with long-acting β₂-agonists (LABAs) were also assessed.

Results

A cohort of 3,268 patients aged 40–65 years was identified (mean age 55.8 years, 48% male). LAMA monotherapy was prescribed to 93% of patients who received an LABD. During the 24-month follow-up, 16% of these patients added COPD medication, 10% switched to an inhaled corticosteroid-containing medication, and 25% discontinued after one LAMA prescription at baseline. Over 12 and 24 months, adherence to LAMA was 40% and 33%, respectively, and adherence to LABA was 29% and 24%, respectively. Over the same time periods, persistence with LAMA monotherapy was 19% and 15%, respectively, and persistence with LABA was 9% and 7%, respectively.

Conclusion

Adherence to newly initiated LAMA monotherapy was low, with one in four patients adding to or switching from LAMA and many patients discontinuing therapy. Adherence to LABA was also low. These results suggest that additional medication to a single LABD may be required in some patients with COPD to achieve optimal disease control.

Chronic Obstructive Pulmonary Disease in the elderly

The prevalence of Chronic Obstructive Pulmonary Disease (COPD) dramatically increases with age, and COPD complicated by chronic respiratory failure may be considered a geriatric condition. Unfortunately, most cases remain undiagnosed because of atypical clinical presentation and difficulty with current respiratory function diagnostic standards. Accordingly, the disease is under-recognized and undertreated. This is expected to impact noticeably the health status of unrecognized COPD patients because a timely therapy could mitigate the distinctive and important effects of COPD on the health status. Comorbidity also plays a pivotal role in conditioning both the health status and the therapy of COPD besides having major prognostic implication. Several problems affect the overall quality of the therapy for the elderly with COPD, and current guidelines as well as results from pharmacological trials only to some extent apply to this patient. Finally, physicians of different specialties care for the elderly COPD patient: physician's specialty largely determines the kind of approach. In conclusion, COPD, in itself a complex disease, becomes difficult to identify and to manage in the elderly. Interdisciplinary efforts are desirable to provide the practicing physician with a multidisciplinary guide to the identification and treatment of COPD.

Microstructural change of the brain in chronic obstructive pulmonary disease: a voxel-based investigation by MRI

BACKGROUND

Cognitive deficit is a common problem in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to prospectively evaluate if MRI can demonstrate microstructural volume loss and the diffusion anisotropic change in subjects with COPD, compared with cognitively normal (CN) subjects.

METHODS

Six subjects with severe COPD, 13 with moderate COPD, and 12 CN subjects underwent isotropic volumetric T1-weighted imaging and diffusion tensor imaging (DTI). Voxel-based statistical analyses among groups were performed on brain volumes, fractional anisotropy (FA) and trace. Cognitive function tests were performed in all subjects, and the Cognitive function tests (CFT) scores were compared among the three groups.

RESULTS

No significant regional difference in volume was found in both the severe and moderate COPD groups relative to the CN group. Comparing between severe COPD and CN, FA was reduced in both the cerebral cortices, and in frontoparietal periventricular white matter. The trace value of the severe COPD group was significantly higher in the cerebral cortices, and in frontoparietal periventricular white matter, than that of the CN group. The severe COPD group showed significantly lower scores in the language-related, visuospatial, and frontal executive functions compared to those of the CN and moderate COPD group.

CONCLUSION

This study demonstrated that COPD could affect the axonal integrity in multiple brain regions, and change in DTI might be related with the severity of the 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.

Driving-Related Neuropsychological Performance in Stable COPD Patients

Background. Cognitive deterioration may impair COPD patient's ability to perform tasks like driving vehicles. We investigated: (a) whether subclinical neuropsychological deficits occur in stable COPD patients with mild hypoxemia (PaO(2) > 55 mmHg), and (b) whether these deficits affect their driving performance. Methods. We recruited 35 stable COPD patients and 10 normal subjects matched for age, IQ, and level of education. All subjects underwent an attention/alertness battery of tests for assessing driving performance based on the Vienna Test System. Pulmonary function tests, arterial blood gases, and dyspnea severity were also recorded. Results. COPD patients performed significantly worse than normal subjects on tests suitable for evaluating driving ability. Therefore, many (22/35) COPD patients were classified as having inadequate driving ability (failure at least in one of the tests), whereas most (8/10) healthy individuals were classified as safe drivers (P = 0.029). PaO(2) and FEV1 were correlated with almost all neuropsychological tests. Conclusions. COPD patients should be warned of the potential danger and risk they face when they drive any kind of vehicle, even when they do not exhibit overt symptoms related to driving inability. This is due to the fact that stable COPD patients may manifest impaired information processing operations.

Shape shifters: biobehavioral determinants and phenomena in symptom research

Symptom assessment and management are critical to patient-centered care. Traditionally, the determinants of a symptom are viewed as separate from the phenomena associated with that symptom. By separating determinants and phenomena, however, the complexity and dynamism of the patient experience are ignored. Likewise, categorizing symptom determinants and phenomena as solely biological or behavioral minimizes their dimensionality and may hinder interdisciplinary dialogue. Here we propose that determinants and phenomena are not fixed but shift between each other depending on perspective. To illustrate this way of thinking the metaphor of the "shape shifter" from folklore is used. A shape shifter moves between states and may be seen differently by the same person at different times or by multiple individuals at one time. To guide discussion, we present 5 exemplars of increasing complexity, wherein a determinant becomes a phenomenon or vice versa, depending upon context. Suggestions for statistical testing of the model are included with each. We conclude by exploring how shifting between determinants and phenomena may affect symptom cluster assessment and management.

Association of chronic obstructive pulmonary disease with cognitive decline in very elderly men

Aim

To determine the change in cognitive function in very elderly men with chronic obstructive pulmonary disease (COPD) over a 3-year period relative to age-and education-matched controls.

Methods

In this hospital-based, prospective case-control study, we evaluated a consecutive series of 110 very elderly men with COPD and 110 control subjects who were hospitalized between January and December 2007. All the subjects performed cognitive tests at baseline and underwent annual evaluations (for 3 years), which included the Mini-Mental State Examination, word list recall, delayed recall, animal category fluency, and the symbol digit modalities test.

Results

In mixed-effects models adjusted for hypertension and coronary heart disease, COPD was associated with a more rapid rate of cognitive decline based on the Mini-Mental State Examination, word list recall, delayed recall, animal category fluency, and the symbol digit modalities test (all p < 0.01) compared to controls.

Conclusion

COPD is associated with a more rapid rate of cognitive decline in very elderly persons.

Disturbed sleep among COPD patients is longitudinally associated with mortality and adverse COPD outcomes

OBJECTIVE

To investigate the cross-sectional association between COPD severity and disturbed sleep and the longitudinal association between disturbed sleep and poor health outcomes.

METHODS

Ninety eight adults with spirometrically-confirmed COPD were recruited through population-based, random-digit telephone dialing. Sleep disturbance was evaluated using a 4-item scale assessing insomnia symptoms as: difficulty falling asleep, nocturnal awakening, morning tiredness, and sleep duration adequacy. COPD severity was quantified by: FEV(1) and COPD Severity Score, which incorporates COPD symptoms, requirement for COPD medications and oxygen, and hospital-based utilization. Subjects were assessed one year after baseline to determine longitudinal COPD exacerbations and emergency utilization and were followed for a median 2.4 years to assess all-cause mortality.

RESULTS

Sleep disturbance was cross-sectionally associated with cough, dyspnea, and COPD Severity Score, but not FEV(1). In multivariable logistic regression, controlling for sociodemographics and body-mass index, sleep disturbance longitudinally predicted both incident COPD exacerbations (OR=4.7; p=0.018) and respiratory-related emergency utilization (OR=11.5; p=0.004). In Cox proportional hazards analysis, controlling for the same covariates, sleep disturbance predicted poorer survival (HR=5.0; p=0.013). For all outcomes, these relationships persisted after also controlling for baseline FEV(1) and COPD Severity Score.

CONCLUSIONS

Disturbed sleep is cross-sectionally associated with worse COPD and is longitudinally predictive of COPD exacerbations, emergency health care utilization, and mortality.

Comorbidities of chronic obstructive pulmonary disease

PURPOSE OF REVIEW

Defining the nature of the association between chronic obstructive pulmonary disease (COPD) and other chronic conditions is of primary importance to improve the health status of COPD patients through the optimal care of comorbidities. We aimed at providing a reasoned guide to understand, recognize and treat comorbidity of COPD with the perspective of shifting from comorbidity to multimorbidity.

RECENT FINDINGS

Select comorbidities, such as atherosclerotic disease, depression, chronic kidney disease, cognitive impairment, obstructive sleep apnea syndrome, lung cancer, osteoporosis, diabetes, heart failure, sarcopenia, aortic aneurysm, arrhythmias and pulmonary embolism are highly prevalent among older COPD patients. Several concerns may affect the management of older COPD patients with comorbidity (e.g. the use of β-blockers in patients with COPD and cardiovascular diseases or concerns about the cardiovascular safety of inhaled COPD drugs).

SUMMARY

Evidence suggests that systemic inflammation may be the link between COPD and comorbidities, but this issue is still debated. Whatever the mechanism underlying comorbidities in COPD may be, it has an important clinical, prognostic and therapeutic impact. Nevertheless, clinical practice guidelines do not take into account comorbidities in their recommendations. Additionally, clinical trials investigating COPD treatment in the context of multimorbidity and considering geriatric outcomes are also distinctly lacking.

Teaching inhaler use in chronic obstructive pulmonary disease patients

PURPOSE

To review barriers to the successful use of inhalers in patients with chronic obstructive pulmonary disease (COPD), and the role of the nurse practitioner (NP) in facilitating optimum inhaler use.

DATA SOURCES

Review of the national and international scientific literature.

CONCLUSIONS

Pharmacologic treatment of COPD patients comprises mainly inhaled medications. Incorrect use of inhalers is very common in these individuals. Some of the consequences of poor inhaler technique include reduced therapeutic dosing, medication adherence, and disease stability, which can lead to increased morbidity, decreased quality of life, and a high burden on the healthcare system. Knowledgeable evaluation and frequent reassessment of inhaler use coupled with education of patients, caregivers, and healthcare professionals can significantly improve the benefits COPD patients derive from inhaled therapy.

IMPLICATIONS FOR PRACTICE

Patient education is vital for correct use of inhalers and to ensure the effectiveness of inhaled medications. The NP has a critical role in assessing potential barriers to successful learning by the patient and improving inhaler technique and medication management. The NP can also facilitate success with inhaled medications by providing up-to-date inhaler education for other healthcare team members, who may then act as patient educators.

Sexual dysfunction and marital satisfaction among the chemically injured veterans

Introduction:

Researches show that chronic illnesses may affect marital adjustment and sexual function. Therefore, the purpose of this research was to recognize marital satisfaction, sexual dysfunction and demographic factors among Chemically Injured Veterans (CIV).

Materials and Methods:

In this descriptive research, we selected and studied 185 cases of CIVs referred to Tehran's hospitals. Data gathering tools were Enrich Marital Satisfaction Scale and structured interview. The items of interview included 28 questions about sexual dysfunction according to DSM-IV-r. The statistical methods were T-test, ANOVA and Correlation.

Results:

The results show that 45.5%, i.e. nearly half of the CIV subjects were dissatisfied with their marriage and marital relationship and the dissatisfaction level in 11% was very high. Other results show that 65/4% of veterans with chemical injuries suffered from a kind of sexual dysfunction. The most common dysfunctions were: erectile problem and libido reduction by 49.2% and 48.6% respectively. Also, results show that there was a relation between demographic factors and sexual dysfunction in CIVs.

Discussion:

As far as the results show, sexual libido reduction rate in CIVs is like that in chronic obstructive pulmonary disease patients. Therefore, sex therapy, psychotherapy and couple therapy must be a component of the treatment of CIVs.