The 2-minute step test is independently associated with cognitive function in older adults with heart failure

Mediating role of cognitive status on performance in the two-minute step test and its normative data among Malaysian community-dwelling older persons

INTRODUCTION

The two-minute step test (2MST) has been used to estimate cardiorespiratory fitness and optimum scores are needed for performing activities of daily living with ease among older persons. However, there is limited information on the mediating role of cognitive impairment on 2MST performance and the 2MST normative data. Hence, we aim to identify the mediating role of cognitive status on performance in the 2MST among community-dwelling older adults and to establish the normative values of the 2MST.

METHODS

Participants aged 60 years and above were recruited through multistage random sampling from four states in Malaysia. The participants performed the 2MST using standard protocols. Mean comparison was done using an independent sample t-test or one-way analysis of variance. The 2MST normative values were then outlined descriptively.

RESULTS

Older age groups (60-69 years: 65.4 ± 21.9 times; 70-79 years: 61.7 ± 22.9 times; ≥80 years: 51.6 ± 24.5 times) had significantly lower levels of 2MST performance (p < 0.001). Women (56.6 ± 20.9 times) and participants with mild cognitive impairment (MCI) (58.7 ± 21.7 times) also had significantly lower levels of 2MST performance (p < 0.001) compared with men (69.1 ± 20.7 times) and participants with normal cognition (63.7 ± 21.6 times). Cognitive status had a significant mediation effect for age and sex on 2MST performance (p < 0.001). Therefore, the 2MST normative values were stratified according to cognitive status, sex, and age groups.

CONCLUSION

Validation of these findings in a larger number of older populations with MCI may provide directions for cardiorespiratory fitness training to be emphasised among older persons with MCI. Geriatr Gerontol Int 2022; ••: ••-••.

Physical fitness in institutionalized older adults with dementia: association with cognition, functional capacity and quality of life

This cross-sectional study investigated the association of physical fitness with cognitive function, functional capacity and quality of life among institutionalized older adults with dementia. One hundred and two older adults aged 78.0 ± 8.4 years, predominantly female (67.6%), with neurocognitive disorder due to Alzheimer’s disease (AD) (49.2%), vascular dementia (14.7%), Parkinson’s disease (2%), dementia with Lewy bodies (2%) or unspecified dementia (32.1%) participated in the present study. Regression analyses were used to examine associations between physical fitness components (Senior Fitness Test) and cognitive function (Mini-Mental State Examination), functional capacity (Katz Index of Independence in Activities of Daily Living) and Quality of Life (QoL)-Alzheimer's Disease scale. Univariate regression indicates that strength, flexibility, agility/dynamic balance and aerobic endurance are relevant for cognitive function, physical capacity and perceived QoL in institutionalized older people with dementia. After multiple regression analyses, adjusted for body mass index (BMI), results showed that aerobic endurance had a significant positive association with Total Katz Index. For both, caregiver perception of QoL-AD and global QoL-AD, BMI remained significantly and positively associated. Agility–dynamic balance presented a significant negative relation with global QoL-AD. Overall, our findings suggest that better physical fitness is important for cognition and autonomous functional capacity and that it has positive repercussions on the QoL in institutionalized older adults with dementia. Consequently, exercise-based therapeutic strategies aiming to improve physical fitness should be implemented.

The Effectiveness of Exercise on Cognitive Performance in Individuals with Known Vascular Disease: A Systematic Review

Patients with known vascular disease are at increased risk for cognitive impairments. Exercise has been shown to improve cognition in healthy elderly populations and those with mild cognitive impairments. We explored the literature to understand exercise as a modality to improve cognition in those with vascular disease, focusing on dose-responses. A systematic review was conducted through 2017 using Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane, Ovid Embase, and Ovid MEDLINE databases. Eligible studies examined effects of exercise on memory and cognition in cardiovascular (CVD) or cerebrovascular disease (CBVD). Data extracted included group characteristics, exercise dosage and outcomes measures employed. Twenty-two studies (12 CVD, 10 CBVD) met the inclusion criteria. Interventions included aerobic, resistance, or mixed training, with neuropsychological test batteries assessing cognition. In CVD populations, five studies demonstrated improved cardiovascular fitness and cognition with aerobic training, and another seven studies suggested a dose-response. In CBVD trials, four studies reported improved cognition, with no effects observed in the fifth study. Another study found enhanced cognition with resistance training and four demonstrated a positive association between functional capacity and cognition following combined aerobic and resistance training. Exercise is able to positively affect cognitive performance in those with known vascular disease. There is evidence to suggest a dose–response relationship. Further research is required to optimize prescription.

Cognitive decline in heart failure

Cognitive impairment (CI) is common in older adults with heart failure (HF). The prevalence of CI is higher among patients with HF than in those without. The spectrum of CI in HF is similar to that observed in the general population and may range from delirium to isolated memory or non-memory-related deficits to dementia. Both HF with reduced ejection fraction and HF with preserved ejection fraction have been associated with defects in different domains of cognition. Numerous risk factors have been shown to contribute to CI in HF. Additionally, various pathophysiological mechanisms related to HF can contribute to cognitive decline. These conditions are not routinely screened for in clinical practice settings with HF populations, and guidelines on optimal assessment strategies are lacking. Validated tools and criteria should be used to differentiate acute cognitive decline (delirium) from chronic cognitive decline such as mild cognitive impairment and dementia. CI in HF has been associated with higher rates of disability and impairment in self-care activities that may in turn increase healthcare cost, hospital readmission and mortality. Early detection of CI may improve clinical outcomes in older adults with HF. Appropriate HF management strategies may also help to reduce CI in patients with HF, and future research is needed to develop and test newer and more effective interventions to improve outcomes in patients with HF and CI.

Reduced Physical Fitness in Patients With Heart Failure as a Possible Risk Factor for Impaired Driving Performance

OBJECTIVE

Reduced physical fitness secondary to heart failure (HF) may contribute to poor driving; reduced physical fitness is a known correlate of cognitive impairment and has been associated with decreased independence in driving. No study has examined the associations among physical fitness, cognition, and driving performance in people with HF.

METHOD

Eighteen people with HF completed a physical fitness assessment, a cognitive test battery, and a validated driving simulator scenario.

RESULTS

Partial correlations showed that poorer physical fitness was correlated with more collisions and stop signs missed and lower scores on a composite score of attention, executive function, and psychomotor speed. Cognitive dysfunction predicted reduced driving simulation performance.

CONCLUSION

Reduced physical fitness in participants with HF was associated with worse simulated driving, possibly because of cognitive dysfunction. Larger studies using on-road testing are needed to confirm our findings and identify clinical interventions to maximize safe driving.

Obesity as a risk factor for poor neurocognitive outcomes in older adults with heart failure

Heart failure (HF) has reached epidemic proportions and is a significant contributor to poor outcomes. HF is an established risk factor for Alzheimer's disease, vascular dementia, and abnormalities on neuroimaging. Moreover, up to 80% of HF patients also exhibit milder impairments on cognitive tests assessing attention, executive function, memory, and language. The mechanisms of cognitive impairment in HF are not entirely clear and involve a combination of physiological processes that negatively impact the brain. Cerebral hypoperfusion and common comorbid conditions in HF are among the most commonly proposed contributors to poor neurocognitive outcomes in this population. Obesity is another likely risk factor for adverse brain changes and cognitive impairment in HF, as it is a known contributor to neurocognitive outcomes in healthy and patient samples. This paper reviews the literature on HF and cognitive function and introduces obesity as a significant risk factor for poor neurocognitive outcomes in this population.

Cardiac rehabilitation is associated with lasting improvements in cognitive function in older adults with heart failure

OBJECTIVE

Heart failure (HF) is a known risk factor for cognitive impairment. Cardiac rehabilitation (CR) may attenuate poor neurocognitive outcomes in HF via improved physical fitness--a significant promoter of cognitive function. However, no study has examined the possible acute and lasting benefits of CR on cognitive function in persons with HF.

METHODS AND RESULTS

Fifty-two patients with HF completed a 12-week Phase II CR program. All participants were administered neuropsychological testing and completed a brief physical fitness assessment at baseline, completion of CR (i.e. 12 weeks), and 12-month follow-up. Repeated measures analyses showed a significant time effect for both attention/executive function and memory (P < 0.05). Attention/executive function performance increased from baseline to 12 weeks and these gains remained up to 12 months; memory was unchanged from baseline to 12 weeks, but then improved between the 12-week and 12-month time points. Physical fitness improved from baseline to 12 weeks and these benefits were maintained 12 months later. Changes in physical fitness and cognitive function over time did not reach a statistically significant association, though poorer physical fitness was associated with decreased cognitive performance at the baseline and 12-month time points.

CONCLUSIONS

CR is associated with both acute and lasting cognitive benefits in patients with HF. Prospective studies with extended follow-ups are needed to clarify the mechanisms that underpin cognitive improvements following CR (e.g., improved cerebral perfusion) and whether CR can ultimately reduce risk for cognitive decline and conditions like Alzheimer's disease in HF.

Better adherence to treatment recommendations in heart failure predicts improved cognitive function at a one-year follow-up

INTRODUCTION

Treatment nonadherence is common in heart failure (HF) and is associated with poor health outcomes in this population. Recent cross-sectional work in heart failure and past work in other medical populations suggest that cognitive function is a key determinant of a patient's ability to adhere to treatment recommendations. However, it is also possible that treatment adherence is an important modifier and predictor of cognitive function, though no study has examined this possibility, and we sought to do so in a sample of heart failure patients.

METHOD

A total of 115 patients with heart failure self-reported adherence to treatment recommendations. The Modified Mini Mental State Examination (3MS), Trail Making Test Parts A and B, and the California Verbal Learning Test-II (CVLT-II) assessed cognitive function. These procedures were performed at baseline and a 12-month follow-up.

RESULTS

Global cognition and memory abilities improved over the 12-month period. Regression analyses controlling for baseline and medical and demographic factors showed that better baseline treatment adherence predicted improved 12-month performances on the 3MS and CVLT-II. Adherence to medication and diet regimens and smoking abstinence emerged as the most important contributors.

CONCLUSIONS

Better treatment adherence predicted improved cognition one year later in HF. Prospective studies that utilize objective assessments of treatment adherence are needed to confirm our findings and examine whether improved treatment adherence preserves cognitive function in heart failure.

COPD is associated with cognitive dysfunction and poor physical fitness in heart failure

OBJECTIVE

To examine the associations among chronic obstructive pulmonary disease (COPD), cognitive function, and physical fitness in heart failure (HF).

BACKGROUND

Cognitive impairment in HF in part stems from medical comorbidities and poor physical fitness. COPD, a frequent co-existing condition in HF, is a risk factor for cognitive impairment and a known cause of poor physical fitness. Yet, the interplay among COPD, cognition, and physical fitness has never been examined in HF.

METHODS

191 HF patients completed a cognitive test battery and brief physical fitness assessment. Diagnostic history of COPD was ascertained via medical chart review.

RESULTS

Regression analyses showed HF patients with COPD exhibited worse attention/executive function and poorer fitness relative to their non-COPD counterparts. Worse fitness correlated with cognitive dysfunction.

CONCLUSIONS

COPD is associated with reduced cognition and worse fitness in HF. Longitudinal work that employs objective assessments of COPD is needed to determine directionality and clarify mechanisms.

Decreased physical activity predicts cognitive dysfunction and reduced cerebral blood flow in heart failure

OBJECTIVE

Cognitive impairment in heart failure (HF) is believed to result from brain hypoperfusion subsequent to cardiac dysfunction. Physical inactivity is prevalent in HF and correlated with reduced cardiac and cognitive function. Yet, no longitudinal studies have examined the neurocognitive effects of physical inactivity in HF. The current study examined whether reduced physical activity increases risk for cognitive impairment and brain hypoperfusion over time in HF.

METHODS

At baseline and 12 months later, 65 HF patients underwent neuropsychological testing, transcranial Doppler ultrasonography, and were asked to wear an accelerometer for seven days.

RESULTS

Lower baseline step count and less time spent in moderate free-living activity best predicted worse attention/executive function and decreased cerebral perfusion at the 12-month follow-up. Decreased baseline cerebral perfusion also emerged as a strong predictor of poorer 12-month attention/executive function.

CONCLUSIONS

Lower physical activity predicted worse cognition and cerebral perfusion 12 months later in HF. Physical inactivity in HF may contribute to cognitive impairment and exacerbate risk for conditions such as Alzheimer's disease. Larger studies are needed to elucidate the mechanisms by which physical inactivity leads to cognitive dysfunction in HF, including clarification of the role of cerebral hypoperfusion.

Cognitive dysfunction mediates the effects of poor physical fitness on decreased functional independence in heart failure

AIM

Heart failure (HF) patients require assistance with activities of daily living (ADL). Poor physical fitness has recently been identified as a contributor to the high rates of disability in HF, though the mechanisms for such effects are unclear. Although not previously examined, decreased fitness might adversely impact ADL in HF through its known association with cognitive impairment, a key correlate of self-care abilities in this population. We sought to test this possibility using a model-based approach.

METHODS

A total of 197 patients with HF completed a physical fitness test and a neuropsychological test battery. A total ADL composite was derived from the Lawton Brody scale. Structural equation modeling tested whether cognitive function mediated the association between physical fitness and total ADL.

RESULTS

Fitness was reduced, and cognitive dysfunction and impaired ADL were prevalent. The initially significant association between fitness and total ADL was attenuated when cognitive function was introduced as a mediator. This model showed good fit (comparative fit index=0.91: root mean-square error of approximations=0.077) with a significant indirect pathway between physical fitness and total ADL through cognitive function: Decreased physical fitness was associated with cognitive dysfunction (β=0.35), which predicted greater assistance with ADL (β=0.22).

CONCLUSIONS

Poor physical fitness might lead to decreased functional independence in HF through its negative effects on cognitive function. Prospective studies are required to confirm our findings, identify other mechanisms by which poor fitness impacts ADL, and examine whether exercise interventions can improve cognition and help preserve ADL independence in HF.

The interactive effects of cerebral perfusion and depression on cognitive function in older adults with heart failure

OBJECTIVE

Depression is common among persons with heart failure (HF) and has been linked to cognitive impairment in this population. The mechanisms of this relationship are unclear, and the current study examined whether cerebral perfusion moderates the association between depressive symptoms and cognitive impairment in patients with HF.

METHODS

Persons with HF (n = 89; mean [standard deviation] age = 67.61 [11.78] years) completed neuropsychological testing and impedance cardiography. Depressive symptoms were assessed using the Beck Depression Inventory II, and transcranial Doppler was used to quantify cerebral perfusion.

RESULTS

Depression was associated with reduced performance on tasks assessing attention/executive function (r = -0.28), language (r = -0.0.30), and motor function (r = -0.28) in unadjusted models (p values <.05). Global cerebral blood flow was correlated with memory performance (r = 0.22, p = .040) but not with other tasks. A moderation analysis was performed using hierarchical regression models for attention/executive function, memory, language, and motor function. For each model, medical and demographic characteristics were entered into the initial blocks, and the final block consisted of an interaction term between global cerebral blood flow velocity and the Beck Depression Inventory II. The interaction between greater depressive symptoms and decreased global cerebral blood flow velocity was associated with greater deficits in attention/executive function (β = .32, ΔR(2) = 0.08, p = .003).

CONCLUSIONS

Depressive symptoms and cerebral hypoperfusion interact to adversely affect cognitive performance in older adults with HF. Longitudinal studies are needed to clarify this relationship and elucidate subsequent neuropathology.

Cardiovascular fitness associated with cognitive performance in heart failure patients enrolled in cardiac rehabilitation

Background

Reduced cognitive function is common in persons with heart failure (HF). Cardiovascular fitness is a known contributor to cognitive function in many patient populations, but has only been linked to cognition based on estimates of fitness in HF. The current study examined the relationship between fitness as measured by metabolic equivalents (METs) from a standardized stress test and cognition in persons with HF, as well as the validity of office-based predictors of fitness in this population.

Methods

Forty-one HF patients enrolled in cardiac rehabilitation completed a standardized exercise stress test protocol, a brief neuropsychological battery, the 2-minute step test (2MST), and a series of medical history and self-report questionnaires.

Results

Maximum METs from stress testing demonstrated incremental predictive validity for attention (β = .41, p = .03), executive function (β = .37, p = .04), and memory domains (β = .46, p = .04). Partial correlations accounting for key medical and demographic characteristics revealed greater METs was associated with the 2MST (r (32) = .41, p = .02) but not with the Duke Activity Status Index (DASI) (r(32) = .24, p = .17).

Conclusion

The current findings indicate that better fitness levels measured by METs is independently associated with better cognitive function in older adults with HF. Results also showed that METs was closely associated with one office-based measure of fitness (2MST), but not another (DASI). Prospective studies are needed to clarify the mechanisms linking fitness and cognitive function in HF.

Depressive symptomatology, exercise adherence, and fitness are associated with reduced cognitive performance in heart failure

OBJECTIVE

Depression is common in heart failure (HF) and associated with reduced cognitive function. The current study used structrual equation modeling to examine whether depression adversely impacts cognitive function in HF through its adverse affects on exercise adherence and cardiovascular fitness.

METHOD

158 HF patients completed neuropsychological testing, physical fitness test, Beck depression inventory-II (BDI-II), and measures assessing exercise adherence and physical exertion.

RESULTS

The model demonstrated excellent model fit and increased scores on the BDI-II negatively affected exercise adherence and cardiovascular fitness. There was a strong inverse association between cardiovascular fitness and cognitive function. Sobel test showed a significant indirect pathway between the BDI-II and cognitive function through cardiovascular fitness.

DISCUSSION

This study suggests depression in HF may adversely impact cognitive function through reduced cardiovascular fitness. Prospective studies are needed to determine whether treatment of depression can lead to better lifestyle behaviors and ultimately improve neurocognitive outcomes in HF.

Poorer physical fitness is associated with reduced structural brain integrity in heart failure

OBJECTIVE

Physical fitness is an important correlate of structural and functional integrity of the brain in healthy adults. In heart failure (HF) patients, poor physical fitness may contribute to cognitive dysfunction and we examined the unique contribution of physical fitness to brain structural integrity among patients with HF.

METHODS

Sixty-nine HF patients performed the Modified Mini Mental State examination (3MS) and underwent brain magnetic resonance imaging. All participants completed the 2-minute step test (2MST), a brief measure of physical fitness. We examined the associations between cognitive performance, physical fitness, and three indices of global brain integrity: total cortical gray matter volume, total white matter volume, and whole brain cortical thickness.

RESULTS

Regression analyses adjusting for demographic characteristics, medical variables (e.g., left ventricular ejection fraction), and intracranial volume revealed reduced performance on the 2MST were associated with decreased gray matter volume and thinner cortex (p<.05). Follow up analyses showed that reduced gray matter volume and decreased cortical thickness were associated with poorer 3MS scores (p<.05).

CONCLUSIONS

Poor physical fitness is common in HF and associated with reduced structural brain integrity. Prospective studies are needed to elucidate underlying mechanisms for the influence of physical fitness on brain health in HF.

Dietary habits moderate the association between heart failure and cognitive impairment

Cognitive impairment is common in heart failure patients. Poor dietary habits are associated with reduced neurocognitive function in other medical populations, including diabetes and Alzheimer's disease. This study examined whether dietary habits help moderate the relationship between heart failure severity and cognitive function. A total of 152 persons with heart failure completed neuropsychological testing and a fitness assessment. Dietary habits were assessed using the Starting the Conversation-Diet questionnaire, a nutrition measure suggested for use in primary care settings. Moderation analyses showed that better dietary habits attenuated the adverse impact of heart failure severity on frontal functioning (b = 1.28, p < 0.05). Follow-up analyses revealed consumption of foods high in sodium was associated with reduced cognitive function (p < 0.05). This study suggests dietary habits can moderate the association between heart failure and performance on tests of attention and executive function. Longitudinal studies are needed to confirm and clarify the mechanisms for our findings.

The additive effects of type-2 diabetes on cognitive function in older adults with heart failure

Background. Medical comorbidity has been theorized to contribute to cognitive impairment in heart failure (HF) patients. Specifically, type-2 diabetes mellitus (T2DM), a common coexisting condition among HF patients, may be an independent predictor of cognitive impairment. Nonetheless, the relationships between T2DM and other risk factors for cognitive impairment among persons with HF are unclear. Methods. Persons with HF (N = 169, 34.3% women, age 68.57 ± 10.28 years) completed neuropsychological testing within a framework of an ongoing study. History of T2DM, along with other medical characteristics, was ascertained through a review of participants' medical charts and self-report. Results. Many participants (34.9%) had a comorbid T2DM diagnosis. After adjustment for demographic and medical characteristics, HF patients with T2DM evidenced significantly greater impairments across multiple cognitive domains than HF patients without T2DM: λ = .92, F(5, 156) = 2.82, P = .018. Post hoc tests revealed significant associations between T2DM and attention (P = .003), executive function (P = .032), and motor functioning (P = .008). Conclusion. The findings suggest additive contributions of T2DM and HF to impairments in attention, executive function, and motor function. Future work is needed to elucidate the mechanisms by which T2DM exacerbates cognitive impairment in HF.