Sarah Garcia

Cerebral Perfusion is Associated With White Matter Hyperintensities in Older Adults With Heart Failure

Cognitive impairment is common in heart failure (HF) and believed to be the result of cerebral hypoperfusion and subsequent brain changes including white matter hyperintensities (WMHs). The current study examined the association between cerebral blood flow and WMHs in patients with HF and the relationship between WMHs and cognitive impairment. Sixty-nine patients with HF completed the Mini-Mental State Examination (MMSE) and underwent echocardiography, transcranial Doppler sonography for cerebral blood flow velocity of the middle cerebral artery, and brain magnetic resonance imaging. Multivariable hierarchical regression analyses controlling for medical and demographic characteristics as well as intracranial volume showed reduced cerebral blood flow velocity of the middle cerebral artery was associated with greater WMHs (β=-0.34, P=.02). Follow-up regression analyses adjusting for the same medical and demographic factors in addition to cerebral perfusion also revealed marginal significance between increased WMHs and poorer performance on the MMSE (β=-0.26, P=.05). This study suggests that reduced cerebral perfusion is associated with greater WMHs in older adults with HF. These findings support the widely proposed mechanism of cognitive impairment in HF patients and prospective studies are needed to confirm these results.

Cognitive function predicts weight loss after bariatric surgery.

BACKGROUND Clinically significant cognitive impairment is found in a subset of patients undergoing bariatric surgery. These difficulties could contribute to a reduced adherence to postoperative lifestyle changes and decreased weight loss. The present study is the first to prospectively examine the independent contribution of cognitive function to weight loss after bariatric surgery. Executive function/attention and verbal memory at baseline were expected to negatively predict the percentage of excess weight loss (%EWL) and body mass index (BMI) at follow-up. Three sites of the Longitudinal Assessment of Bariatric Surgery parent project were used: Columbia (New York, NY), Cornell (Princeton, NJ), and the Neuropsychiatric Research Institute (Fargo, ND). METHODS A total of 84 individuals enrolled in the Longitudinal Assessment of Bariatric Surgery project undergoing bariatric surgery completed a cognitive evaluation at baseline. The BMI and %EWL were calculated at the 12-week and 12-month postoperative follow-up visits. RESULTS Clinical impairment in task performance was most prominent in tasks associated with verbal recall and recognition (14.3-15.5% of the sample) and perseverative errors (15.5%). After accounting for demographic and medical variables, the baseline test results of attention/executive function and memory predicted the BMI and %EWL at 12 months but not at 12 weeks. CONCLUSIONS These results have demonstrated that baseline cognition predicts for greater %EWL and lower BMI 12 months after bariatric surgery. Additional work is needed to clarify the degree to which cognition contributes to adherence and the potential mediation of cognition on the relationship between adherence and weight loss in this group.

Depression is associated with cognitive dysfunction in older adults with heart failure.

Persons with heart failure (HF) frequently exhibit cognitive impairment with deficits in attention and memory. Depression is common in HF though its possible contribution to cognitive impairment is unknown. Cognitive dysfunction and depression may share common mechanisms in HF, as both are associated with similar abnormalities on neuroimaging. A total of 116 participants with HF (68.53 ± 9.30 years) completed a neuropsychological battery and self-report measures of depression. Regression models showed depression incrementally and independently predicted test performance in all cognitive domains. Follow-up partial correlations revealed that greater depressive symptoms were associated with poorer performance on tests of attention, executive function, psychomotor speed, and language. These results indicate that depressive symptoms are associated with poorer cognitive performance in HF though further work is needed to clarify mechanisms for this association and possible cognitive benefits of treating depression in persons with HF.

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

BackgroundReduced 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.MethodsForty-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.ResultsMaximum 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).ConclusionThe 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.

Neurocognitive Effects of Obesity and Bariatric Surgery.

This review paper will discuss the recent literature examining the relationship between obesity and neurocognitive outcomes, with a particular focus on cognitive changes after bariatric surgery. Obesity is now recognized as an independent risk factor for adverse neurocognitive outcomes, and severely obese persons appear to be at even greater risk. Bariatric surgery is associated with rapid improvements in cognitive function that persist for at least several years, although the mechanisms underlying these improvements are incompletely understood. Assessment of cognitive impairment in bariatric surgery patients is challenging, and improved methods are needed, as poorer performance on neuropsychological tests of memory and executive function leads to poorer clinical weight outcomes. In addition to its clinical importance, further study in this area will provide key insight into obesity-related cognitive dysfunction and clarify the possibility of an obesity paradox for neurological outcomes.

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 (&bgr; = .32, &Dgr;R2 = 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.

Poor sleep quality and reduced cognitive function in persons with heart failure

Cognitive dysfunction is common in persons with heart failure (HF), with an estimated 25–75% of HF patients exhibiting deficits on neuropsychological testing [1]. Deficits are particularly common on tests of attention, memory, and executive functioning [2–3]. A growing number of factors have been shown to contribute to the cognitive dysfunction found in persons with HF, including decreased cerebral blood flow velocity [4]. It appears likely that poor sleep is another contributor to cognitive dysfunction in HF as past studies suggest 50–80% of HF patients experience sleep difficulties [5–6]. In turn, poor sleep is associated with cognitive impairment in both patient and healthy samples in past work [7–8]. The current study examined whether reported sleep problems are associated with poorer cognitive functioning in a sample of older adults with HF. Additional analyses were performed to examine whether poor sleep quality would also be associated with other psychosocial outcomes in persons with HF, including activities of daily living, quality of life, and depressive symptoms. One hundred and fifty-nine older adults diagnosed with systolic HF were recruited from Summa Health System in Akron, OH (68.53±9.30 years; 36.2% female). Comorbid medical conditions included hypertension (79.8%), elevated cholesterol (68%), coronary artery bypass graft (35.2%), and type 2 diabetes (30.4%). All participants were between 50–85 years of age, English-speaking, and had an established diagnosis of New York Heart Association (NYHA) class II or III HF. Exclusion criteria included a history of significant neurological disorder (e.g. dementia, stroke), head injury, severe psychiatric disorder (e.g. schizophrenia, bipolar disorder), and substance use. As sleep apnea is common in persons with HF [9] and known to independently suppress cognitive function in other samples [10–11], HF patients with a diagnosis of sleep apnea were excluded from the current analyses. All procedures were approved by the local Institutional Review Board and written consent was obtained from all participants. Participants completed a 90-minute neuropsychological battery, followed by the 2-minute step test. A series of medical history and self-report questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI-II), Lawton-Brody Activities of Daily Living Questionnaires (ADL), and the 12-Item Short Form Health Survey (SF-12) were then completed by all participants. Consistent with past work [5–6], sleep problems were common within our sample of older adults with HF, as the sample had an average Global PSQI of 15.23 ± 7.12 and 96.0% had a Global PSQI score in the impaired range (>5). Difficulties falling asleep (20.8%), staying asleep (49.6%), as well as interruptions in sleep due to bathroom use (56.0%) were those problems most commonly reported. Cognitive impairment was also prevalent as participants averaged 92.87 ± 5.49 on the Modified Mini-Mental Status Exam (3MS), with 24.8% of the sample scoring below 90, 30.4% between 90–95, and 40% above a 95. After adjusting for age, gender, education, HF severity, diabetes, and hypertension, Global PSQI demonstrated incremental predictive validity for executive functioning and attention (ΔF(1,117) = 3.96, ΔR2 = .02, p .05). See Table 1. Table 1 Association of Sleep Quality with Cognitive Functions in Older Adults with Heart Failure (N = 125): A summary of hierarchical regressions. Again, after adjusting for age, gender, education, HF severity, diabetes, and hypertension, partial correlations revealed that Global PSQI was significantly associated with SF-12 MCS (r(117) = −0.44, p < .01), SF-12 PCS (r (117) = −0.37, p < .01), the BDI-II (r (117) = 0.38, p < .05), instrumental ADL (r (117) = −0.22, p < .05), and basic ADL (r (117) = −0.19, p < .05). Poorer sleep quality was associated with reduced quality of life, increased depressive symptomatology, and reduced instrumental and basic ADL performance. The current results show that poor reported sleep quality is associated with reduced performance on tests of attention/executive function and a similar trend emerged for memory. This relationship between sleep quality and cognitive impairment has been reported in other samples, including healthy adults [12–13] and less severe forms of cardiovascular disease [14]. While many HF patients already experience decreased cerebral blood flow, impaired sleep has also been linked to similar effects on blood flow and could further exacerbate cognitive impairment [15]. Additional work is needed to clarify this possibility. Within this sample of older adults with HF, greater reported sleep problems are also associated with poorer psychosocial outcomes. Similar to other populations [16–17], poor sleep is associated with reduced quality of life, greater depression, and reduced functional independence. Such findings raise the possibility that sleep problems are a possible therapeutic target to improve outcomes in persons with HF. Exercise and sleep education have been beneficial to quality of sleep, mood, and quality of life in other populations [18–19]. Likewise, treatment of depression may improve sleep, as the directionality of this relationship is unclear [20]. The current findings are limited in several ways. Future research is needed to clarify the mechanisms by which sleep influences cognitive functioning in this population as well as the types of sleep problems which lead to impairment. Neuroimaging studies may provide clues to how sleep and heart failure contribute to cognitive decline [21]. The cognitive dysfunction found in HF may cause patients to over- or under- estimate their sleep problems and objective measures would clarify possible discrepancies and provide information for future treatment interventions [22]. Finally, prospective studies should also be conducted to better understand how sleep problems progress in HF and how they might correspond to cognitive function and other outcomes. For example, cognitive impairment is associated with elevated mortality risk in persons with HF [23] and the contribution of poor sleep and other factors to this risk are unknown. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology [24].

The effects of a brief, water-based exercise intervention on cognitive function in older adults.

Physical inactivity is a modifiable risk factor for accelerated cognitive decline in older adults. Water-based exercise provides the same physiological benefits as land-based exercise with reduced risk of acute injury. The current study evaluated the effects of a brief, water-based exercise intervention on cognitive functioning and cardiovascular fitness in a group of community dwelling older adults. The exercise group (n = 27, M(age) = 63.26 ± 7.64, 78% female) attended one moderate intensity water aerobics class per day for six consecutive days whereas the control group (n = 33, M(age) = 65.67 ± 6.69, 75% female) continued their typical routine. Neuropsychological and cardiovascular fitness tests were given the week before and the week after the intervention to both groups. The exercise group demonstrated significant improvements in cardiovascular fitness, as well as executive function, attention, and memory over controls. This suggests a brief exercise program can provide benefits for older adults.

Patient reports of cognitive problems are not associated with neuropsychological test performance in bariatric surgery candidates

BACKGROUND Recent work shows that cognitive deficits are common in bariatric surgery candidates and are associated with reduced weight loss at 12 months postoperatively. Because preoperative neuropsychological assessment is not available for all patients at all sites, many care providers ask patients to self-report their level of cognitive dysfunction. However, the accuracy of patient self-report of cognitive abilities has not been empirically examined. METHODS Eighty-one bariatric surgery candidates completed self-report measures of cognitive functioning and neuropsychological tests of memory and other cognitive abilities. RESULTS Analyses found no association between subjective report of cognitive function and objective performance on neuropsychological testing. However, persons with history of major depressive disorder reported experiencing greater cognitive deficits. CONCLUSIONS These findings suggest that bariatric surgery candidates have little insight into their current level of cognitive function. Future work is needed to confirm these findings and identify brief, objective measures of cognitive function that are sensitive to deficits in bariatric surgery candidates.

Cognitive performance in older adults with stable heart failure: longitudinal evidence for stability and improvement.

ABSTRACT Cognitive impairment is prevalent in heart failure (HF), though substantial variability in the pattern of cognitive impairment is found across studies. To clarify the nature of cognitive impairment in HF, we examined longitudinal trajectories across multiple domains of cognition in HF patients using latent growth class modeling. 115 HF patients completed a neuropsychological battery at baseline, 3-months and 12-months. Participants also completed the Beck Depression Inventory-II (BDI-II). Latent class growth analyses revealed a three-class model for attention/executive function, four-class model for memory, and a three-class model for language. The slope for attention/executive function and language remained stable, while improvements were noted in memory performance. Education and BDI-II significantly predicted the intercept for attention/executive function and language abilities. The BDI-II also predicted baseline memory. The current findings suggest that multiple performance-based classes of neuropsychological test performance exist within cognitive domains, though case-controlled prospective studies with extended follow-ups are needed to fully elucidate changes and predictors of cognitive function in HF.