Brain metabolites in autonomic regulatory insular sites in heart failure

Heart failure-induced brain myelin changes and differences between sexes

Heart failure (HF) leads to brain injury in autonomic, respiratory, mood, and cognitive control sites, revealed as tissue volume loss, altered metabolites, and impaired diffusion tissue properties. The extent of myelin changes in HF and variations within sexes are unclear. Our aim was to examine regional brain subcortical and white matter myelin integrity in HF patients over control subjects, as well as differences between sexes using T1- and T2-weighted clinical images. We acquired T1- and T2-weighted images from 63 HF patients and 129 controls using a 3.0-Tesla MRI scanner. Using T1- and T2-weighted images, ratio maps were computed, normalized to a common space, smoothed, and compared between groups (ANCOVA; covariates: age and sex; SPM12, false discovery rate, p < .010), as well as between male versus female HF (ANCOVA; covariate: age; SPM12, uncorrected p < .005). Multiple brain areas in HF showed decreased myelin integrity, including the amygdala, hippocampus, cingulate, insula, cerebellum, prefrontal cortices, and multiple white matter areas, compared to controls. Female HF patients showed more brain injuries in the parietal, prefrontal and frontal, hippocampus, amygdala, pons, cerebellar, insula, and corpus callosum compared to male HF patients. HF subjects showed compromised subcortical and white matter myelin integrity, especially in sites regulating autonomic, respiratory, mood, and cognition, with more changes in females over males. These findings provide a structural basis for the enhanced symptoms identified in female over male HF patients with similar disease severity.

What is the role of interoception in the symptom experience of people with a chronic condition? A systematic review

BACKGROUND

Interoception, the ability of the organism to sense, interpret, and regulate signals originating from within the body, plays an important role in how individuals perceive and respond to symptoms. However, there is scarce evidence on the role of interoception in the symptom experience of people with chronic conditions.

AIM

To synthesize the role of interoception in the symptom experience of adults with a chronic condition.

METHODS

Systematic review. We searched PubMed, Psychinfo, Embase, CINAHL, and Science Citation Index-Expanded. We included primary research (all study designs) addressing our study aim, published between 2013-2021, and measuring at least one dimension of interoception. Any chronic condition and any symptom were included. No language limits were applied. Only the adult population was included.

RESULTS

We included 18 quantitative studies investigating the relationship between three interoceptive dimensions (i.e., accuracy, sensibility, awareness) and condition-specific symptoms in 10 chronic conditions. People with chronic conditions had lower interoceptive accuracy than healthy controls. Higher interoceptive sensibility was associated with lower symptom severity/frequency. Higher interoceptive accuracy was associated with lower symptom severity/frequency in half of the studies, while the other half reported the opposite. Only one study explored interoceptive awareness.

CONCLUSION

Interoceptive abilities are lower in patients with chronic conditions. Higher interoceptive sensibility is associated with lower symptom severity/frequency, but this relationship is unclear when it comes to interoceptive accuracy and awareness.

Exploring the brain with sleep-related injuries, and fixing it

The focus of my research efforts rests with determining dysfunctional neural systems underlying disorders of sleep, and identifying interventions to overcome those disorders. Aberrant central and physiological control during sleep exerts serious consequences, including disruptions in breathing, motor control, blood pressure, mood, and cognition, and plays a major role in sudden infant death syndrome, congenital central hypoventilation, and sudden unexpected death in epilepsy, among other concerns. The disruptions can be traced to brain structural injury, leading to inappropriate outcomes. Identification of failing systems arose from the assessment of single neuron discharge in intact, freely moving and state-changing human and animal preparations within multiple systems, including serotonergic action and motor control sites. Optical imaging of chemosensitive, blood pressure and other breathing regulatory areas, especially during development, were useful to show integration of regional cellular action in modifying neural output. Identification of damaged neural sites in control and afflicted humans through structural and functional magnetic resonance imaging procedures helped to identify the sources of injury, and the nature of interactions between brain sites that compromise physiological systems and lead to failure. Interventions to overcome flawed regulatory processes were developed, and incorporate noninvasive neuromodulatory means to recruit ancient reflexes or provide peripheral sensory stimulation to assist breathing drive to overcome apnea, reduce the frequency of seizures, and support blood pressure in conditions where a failure to perfuse can lead to death.

Randomized Controlled Trial of a Cognitive Intervention to Improve Memory in Heart Failure

BACKGROUND

The objective of this 3-arm randomized controlled trial was to evaluate efficacy of computerized cognitive training (CCT) to improve primary outcomes of delayed recall memory and serum brain-derived neurotrophic factor (BDNF) levels and secondary outcomes of working memory, instrumental activities of daily living (IADL), and health-related quality of life (HRQL) among patients with heart failure (HF).

METHODS AND RESULTS

Patients (N = 256) were randomly assigned to 8 weeks of CCT using BrainHQ, computerized crossword puzzles active control intervention, and usual care. All patients received weekly nurse enhancement interventions. Data were collected at enrollment and baseline visits and at 10 weeks and 4 and 8 months. In mixed effects models, there were no statistically significant group or group by time differences in outcomes. There were statistically significant differences over time in all outcomes in all groups. Patients improved over time on measures of delayed recall memory, working memory, IADL, and HRQL and had decreased serum BDNF.

CONCLUSIONS

CCT did not improve outcomes compared with the active control intervention and usual care. Nurse enhancement interventions may have led to improved outcomes over time. Future studies are needed to test nurse enhancement interventions in combination with other cognitive interventions to improve memory in HF.

LAYSUMMARY

In 256 patients with heart failure, 8 weeks of computerized cognitive training, computerized crossword puzzles, or usual care were studied for effects on (1st) recall memory and serum brain-derived neurotrophic factor (BDNF) and (2nd) working memory, instrumental activities of daily living (IADL), and health-related quality of life (HRQL). Measurements were at baseline, 10 weeks, 4- and 8-months. Nurse enhancement interventions (e.g., support, assessment) were provided. Recall memory, working memory, IADL, and HRQL improved over time. There were no statistically significant differences among treatment groups over time. BDNF unexpectedly decreased. Nurse enhancement interventions may explain improved outcomes. Future studies are needed.

The influence of dyadic congruence and satisfaction with dyadic type on patient self-care in heart failure

BACKGROUND

Chronic illness management is increasingly carried out at home by individuals and their informal caregivers (dyads). Although synergistic in concept, the nuances of dyadic congruence in caring for patients with heart failure are largely unexamined.

AIMS

The purpose of this study was to examine the role of dyadic-type congruence on patient self-care (maintenance, symptom perception, and management) while controlling for actor and partner effects.

METHODS

This secondary data analysis of 277 dyads consisted of a series of multilevel models to examine the impact of dyadic congruence on a patient's self-care maintenance, symptom perception, and self-care management. Patient-level and caregiver-level data were input into each model simultaneously to account differential appraisals of factors related to the dyad.

RESULTS

Bivariate analyses yielded dyad congruence which was associated with better patient self-care maintenance, symptom perception and management. However, after multilevel models were constructed, dyad congruence was found to be a significant predictor of patient's symptom perception scores, but not self-care maintenance or management scores. Caregiver's satisfaction with the dyad was differentially and significantly associated with self-care - it was inversely associated with patient self-care maintenance and positively associated with patient self-care management.

CONCLUSION

This is the first study, to our knowledge, reporting that congruence in heart failure dyads is associated with better patient symptom perception and this advances our prior hypothesis that dyad typologies could be used to predict patient self-care performance. Since symptom perception is the key to preventing heart failure exacerbation, screening heart failure patient and caregiver dyads for congruence is important in clinical settings.

Neuropsychological Assessment and Screening in Heart Failure: a Meta-Analysis and Systematic Review

A variety of neuropsychological changes secondary to heart failure have been documented in the literature. However, what remains unclear are which neuropsychological abilities are the most impacted by heart failure and what tests have the sensitivity to measure that impact. Eight databases were searched for articles that examined the neuropsychological functioning of patients with heart failure. Some of the inclusion criteria were articles had to have a heart failure group with a demographically comparable control group and standardized neuropsychological testing. Exclusion criteria included articles with a heart failure group with any other type of major organ failure, or comparisons that were between different classes of heart failure rather than between a heart failure and non-heart failure group. A total of 33 articles met the inclusion criteria (total heart failure sample n = 8900) and provided effect size data for 20 neuropsychological domains. All observed domain-level differences between heart failure and non-heart failure groups were statistically significant, except for simple motor functioning and confrontation naming. The greatest differences in performance were in executive functioning, global cognition, complex psychomotor speed, and verbal memory. The highest effect sizes came from Trail-Making Test-Part B, CAMCOG, Symbol Digit Modality Test, and California Verbal Learning Test. The neuropsychological patterns of heart failure suggested diffuse cognitive involvement, with higher-level processes being most affected. It is important to track neurocognition in this clinical population since neuropsychological impairment is prevalent, and screening measures appear to be reliable. Such screening and further assessment would inform future medical treatment and may improve patient care management.

The central nervous system and heart failure

The view that chronic heart failure was exclusively a disease of the heart dominated the cardiovascular literature until relatively recently. However, over the last 40 years it has increasingly come to be seen as a multisystem disease. Aside from changes in the sympathetic and parasympathetic nervous systems and the renin-angiotensin-aldosterone system, adaptations to the lungs, muscles and gastrointestinal tract have been clearly documented. It is clear that the brain and CNS are also affected in patients with heart failure, although this is often under recognized. The purpose of this review is to summarize the changes in the structure and biochemical function of the CNS in patients with chronic heart failure and to discuss their potential importance.

Integrating Symptoms Into the Middle-Range Theory of Self-Care of Chronic Illness

The Middle-Range Theory of Self-Care of Chronic Illness has been used widely since it was first published in 2012. With the goal of theoretical refinement in mind, we evaluated the theory to identify areas where the theory lacked clarity and could be improved. The concept of self-care monitoring was determined to be underdeveloped. We do not yet know how the process of symptom monitoring influences the symptom appraisal process. Also, the manner in which self-care monitoring and self-care management are associated was thought to need refinement. As both of these issues relate to symptoms, we decided to enrich the Middle-Range Theory with knowledge from theories about symptoms. Here, we propose a revision to the Middle-Range Theory of Self-Care of Chronic Illness where symptoms are clearly integrated with the self-care behaviors of self-care maintenance, monitoring, and management.

Psychometric Testing of the Revised Self-Care of Heart Failure Index

BACKGROUND

Self-care is essential in people with chronic heart failure (HF). The process of self-care was refined in the revised situation specific theory of HF self-care, so we updated the instrument measuring self-care to match the updated theory. The aim of this study was to test the psychometric properties of the revised 29-item Self-Care of Heart Failure Index (SCHFI).

METHODS

A cross-sectional design was used in the primary psychometric analysis using data collected at 5 sites in the United States. A longitudinal design was used at the site collecting test-retest data. We tested SCHFI validity with confirmatory factor analysis and predictive validity in relation to health-related quality of life. We tested SCHFI reliability with Cronbach α, global reliability index, and test-retest reliability.

RESULTS

Participants included 631 adults with HF (mean age, 65 ± 14.3 years; 63% male). A series of confirmatory factor analyses supported the factorial structure of the SCHFI with 3 scales: Self-Care Maintenance (with consulting behavior and dietary behavior dimensions), Symptom Perception (with monitoring behavior and symptom recognition dimensions), and Self-Care Management (with recommended behavior and problem-solving behavior dimensions). Reliability estimates were 0.70 or greater for all scales. Predictive validity was supportive with significant correlations between SCHFI scores and health-related quality-of-life scores.

CONCLUSIONS

Our analysis supports validity and reliability of the SCHFI v7.2. It is freely available to users on the website: www.self-care-measures.com.

Heart and brain interaction in patients with heart failure: overview and proposal for a taxonomy. A position paper from the Study Group on Heart and Brain Interaction of the Heart Failure Association

Heart failure (HF) is a complex clinical syndrome with multiple interactions between the failing myocardium and cerebral (dys-)functions. Bi-directional feedback interactions between the heart and the brain are inherent in the pathophysiology of HF: (i) the impaired cardiac function affects cerebral structure and functional capacity, and (ii) neuronal signals impact on the cardiovascular continuum. These interactions contribute to the symptomatic presentation of HF patients and affect many co-morbidities of HF. Moreover, neuro-cardiac feedback signals significantly promote aggravation and further progression of HF and are causal in the poor prognosis of HF. The diversity and complexity of heart and brain interactions make it difficult to develop a comprehensive overview. In this paper a systematic approach is proposed to develop a comprehensive atlas of related conditions, signals and disease mechanisms of the interactions between the heart and the brain in HF. The proposed taxonomy is based on pathophysiological principles. Impaired perfusion of the brain may represent one major category, with acute (cardio-embolic) or chronic (haemodynamic failure) low perfusion being sub-categories with mostly different consequences (i.e. ischaemic stroke or cognitive impairment, respectively). Further categories include impairment of higher cortical function (mood, cognition), of brain stem function (sympathetic over-activation, neuro-cardiac reflexes). Treatment-related interactions could be categorized as medical, interventional and device-related interactions. Also interactions due to specific diseases are categorized. A methodical approach to categorize the interdependency of heart and brain may help to integrate individual research areas into an overall picture.

The Role of Heart Failure, Daytime Sleepiness, and Disturbed Sleep on Cognition

Disturbed sleep and daytime sleepiness may interfere with possible direct relationships between heart failure (HF) and cognition, yet there is limited research investigating this relationship. We aimed to investigate possible mediating roles of disturbed sleep and daytime sleepiness on the relationship between HF and selected cognitive domains among individuals with and without HF. In a cross-sectional design study, we examined the data of 841 older adults with and without HF from the Aging, Demographics, and Memory Study (ADAMS). We found individuals with HF were likely to have a higher degree of disturbed sleep and daytime sleepiness. Both disturbed sleep and daytime sleepiness were significant predictors of cognition. We found that only daytime sleepiness mediated the relationship between the presence of HF and cognitive domains, such as in attention, memory, and executive function after controlling for covariates. Interventions to improve daytime sleepiness among individuals with HF may also help improving cognition.

Lateralized Resting-State Functional Brain Network Organization Changes in Heart Failure

Heart failure (HF) patients show brain injury in autonomic, affective, and cognitive sites, which can change resting-state functional connectivity (FC), potentially altering overall functional brain network organization. However, the status of such connectivity or functional organization is unknown in HF. Determination of that status was the aim here, and we examined region-to-region FC and brain network topological properties across the whole-brain in 27 HF patients compared to 53 controls with resting-state functional MRI procedures. Decreased FC in HF appeared between the caudate and cerebellar regions, olfactory and cerebellar sites, vermis and medial frontal regions, and precentral gyri and cerebellar areas. However, increased FC emerged between the middle frontal gyrus and sensorimotor areas, superior parietal gyrus and orbito/medial frontal regions, inferior temporal gyrus and lingual gyrus/cerebellar lobe/pallidum, fusiform gyrus and superior orbitofrontal gyrus and cerebellar sites, and within vermis and cerebellar areas; these connections were largely in the right hemisphere (p<0.005; 10,000 permutations). The topology of functional integration and specialized characteristics in HF are significantly changed in regions showing altered FC, an outcome which would interfere with brain network organization (p<0.05; 10,000 permutations). Brain dysfunction in HF extends to resting conditions, and autonomic, cognitive, and affective deficits may stem from altered FC and brain network organization that may contribute to higher morbidity and mortality in the condition. Our findings likely result from the prominent axonal and nuclear structural changes reported earlier in HF; protecting neural tissue may improve FC integrity, and thus, increase quality of life and reduce morbidity and mortality.

Forebrain neurocircuitry associated with human reflex cardiovascular control

Physiological homeostasis depends upon adequate integration and responsiveness of sensory information with the autonomic nervous system to affect rapid and effective adjustments in end organ control. Dysregulation of the autonomic nervous system leads to cardiovascular disability with consequences as severe as sudden death. The neural pathways involved in reflexive autonomic control are dependent upon brainstem nuclei but these receive modulatory inputs from higher centers in the midbrain and cortex. Neuroimaging technologies have allowed closer study of the cortical circuitry related to autonomic cardiovascular adjustments to many stressors in awake humans and have exposed many forebrain sites that associate strongly with cardiovascular arousal during stress including the medial prefrontal cortex, insula cortex, anterior cingulate, amygdala and hippocampus. Using a comparative approach, this review will consider the cortical autonomic circuitry in rodents and primates with a major emphasis on more recent neuroimaging studies in awake humans. A challenge with neuroimaging studies is their interpretation in view of multiple sensory, perceptual, emotive and/or reflexive components of autonomic responses. This review will focus on those responses related to non-volitional baroreflex control of blood pressure and also on the coordinated responses to non-fatiguing, non-painful volitional exercise with particular emphasis on the medial prefrontal cortex and the insula cortex.