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1.  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 < .05). Follow-up analyses revealed consumption of foods high in sodium was associated with reduced cognitive function (p < .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.
PMCID: PMC5022366  PMID: 23663211
Cognitive impairment; Dietary habits; Frontal functioning; Heart failure; Nutrition
2.  Executive Dysfunction is Independently Associated with Reduced Functional Independence in Heart Failure 
Journal of clinical nursing  2013;23(5-6):829-836.
Aims and Objectives
To examine the independent association between executive function with instrumental activities of daily living and health behaviors in older adults with heart failure.
Executive function is an important contributor to functional independence as it consists of cognitive processes needed for decision-making, planning, organizing, and behavioral monitoring. Impairment in this domain is common in heart failure patients and associated with reduced performance of instrumental activities of daily living in many medical and neurological populations. However, the contribution of executive functions to functional independence and healthy lifestyle choices in heart failure patients has not been fully examined.
Cross-sectional analyses.
175 heart failure patients completed a neuropsychological battery and echocardiogram. Participants also completed the Lawton-Brody instrumental activities of daily living scale and reported current cigarette use.
Hierarchical regressions revealed reduced executive function was independently associated with worse instrumental activity of daily living performance with a specific association for decreased ability to manage medications. Partial correlations showed executive dysfunction was associated with current cigarette use.
Our findings suggest that executive dysfunction is associated with poorer functional independence and contributes to unhealthy behaviors in heart failure. Future studies should examine whether heart failure patients benefit from formal organization schemae (i.e., pill organizers) to maintain independence.
Relevance to Clinical Practice
Screening of executive function in heart failure patients may provide key insight into their ability to perform daily tasks, including management of treatment recommendations.
PMCID: PMC5022367  PMID: 23650879
Cognition; executive functions; heart failure; instrumental activities of daily living
3.  Depressive Symptomatology, Exercise Adherence and Fitness are Associated with Reduced Cognitive Performance in Heart Failure 
Journal of aging and health  2013;25(3):459-477.
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.
158 HF patients completed neuropsychological testing, physical fitness test, Beck Depression Inventory-II (BDI-II), and measures assessing exercise adherence, and physical exertion.
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.
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.
PMCID: PMC5022365  PMID: 23378527
Cognitive function; cardiovascular fitness; depression; exercise adherence; heart failure
4.  Cognitive Reserve Moderates the Association between Heart Failure and Cognitive Impairment 
Cognitive impairment in persons with heart failure is common. Theories of cognitive reserve suggest that premorbid factors, such as intellectual ability, may provide a buffer against cognitive impairment due to neuropathological insult. No study has examined the influence of cognitive reserve on cognitive functioning in older adults with heart failure.
This study examined whether cognitive reserve moderates the relationship between heart failure severity and cognitive function.
A total of 157 persons with heart failure (69.26 ± 9.26 years; 39% female) completed neuropsychological testing and a brief fitness assessment. Cognitive reserve was operationalized using estimated premorbid intellect on American National Adult Reading Test (AMNART).
A moderation analysis was performed using a hierarchical regression models for each cognitive domain. An interaction term between the AMNART and 2-minute step test was created and entered into the final block of the model, with demographic, psychosocial, and heart failure severity entered in the previous blocks. The interaction term was significant for attention (t(155) = −2.54, p = .012), executive function (t(155) = −3.30, p = .001), and language (t(155) = −2.83, p = .005) domains.
The current findings suggest that cognitive reserve moderates the association between heart failure severity and cognitive function in multiple cognitive domains. Further work is needed to clarify the mechanisms by which cognitive reserve attenuates cognitive impairment in this population.
PMCID: PMC4993107  PMID: 22034987
heart failure; cognitive reserve; cognitive function; cardiovascular disease; neuropsychology
5.  Cognitive Performance in Older Adults with Stable Heart Failure: Longitudinal Evidence for Stability and Improvement 
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.
PMCID: PMC3858403  PMID: 23906182
Heart failure; trajectories; cognitive function; longitudinal; cognitive profile
6.  Randomized Controlled Trial of Mindfulness-based Stress Reduction for Prehypertension 
Psychosomatic medicine  2013;75(8):10.1097/PSY.0b013e3182a3e4e5.
Mindfulness-based stress reduction (MBSR) is an increasingly popular practice demonstrated to alleviate stress and treat certain health conditions. MBSR may reduce elevated blood pressure (BP). Treatment guidelines recommend lifestyle modifications for BP in the prehypertensive range (SBP 120–139 or DBP 80–89), followed by antihypertensives if BP reaches hypertensive levels. MBSR has not been thoroughly evaluated as a treatment for prehypertension. A randomized clinical trial of MBSR for high BP was conducted to determine whether BP reductions associated with MBSR exceed those observed for an active control condition consisting of progressive muscle relaxation training (PMR).
56 men (43%) and women (57%) averaging 50.3 (SD = 6.5) years of age (91% Caucasian) with unmedicated BP in the prehypertensive range were randomized to 8 weeks of MBSR or PMR delivered in a group format. Treatment sessions were administered by 1 treatment provider and lasted approximately 2.5 hours each week. Clinic BP was the primary outcome measure. Ambulatory BP was a secondary outcome measure.
Analyses were based on intent-to-treat. Patients randomized to MBSR exhibited a 4.8 mm Hg reduction in clinic SBP, which was larger than the 0.7 mm Hg reduction observed for PMR, p = .016. Those randomized to MBSR exhibited a 1.9 mm Hg reduction in DBP, compared to a 1.2 mm Hg increase for PMR, p = .008. MBSR did not result in larger decreases in ambulatory BP than PMR.
MBSR resulted in a reduction in clinic SBP and DBP compared to PMR.
PMCID: PMC3834730  PMID: 24127622
Mindfulness; meditation; prehypertension; blood pressure; clinical trial; MBSR
7.  The Interactive Effects of Cerebral Perfusion and Depression on Cognitive Function in Older Adults with Heart Failure 
Psychosomatic medicine  2013;75(7):632-639.
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 symptomatology and cognitive impairment in patients with HF.
Persons with HF (N=89; 67.61 (SD = 11.78) years of age) completed neuropsychological testing and impedance cardiography. Depressive symptomatology was assessed using the Beck Depression Inventory-II and transcranial doppler was used to quantify cerebral perfusion.
Depression was associated with reduced performance on tasks assessing attention/executive function (r=−0.28), language (r=−.0.30) and motor function (r=−.28) in unadjusted models (p-values < 0.05). Global cerebral blood flow was correlated with memory performance (r=0.22, p=.040) but not to 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 (CBF-V) and the BDI-II. The interaction between greater depressive symptomatology and decreased global CBF-V was associated with greater deficits in attention/executive function (β = .32, ΔR2 = .08, p = .003).
Depressive symptomatology 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.
PMCID: PMC3770733  PMID: 23873714
Cognitive impairment; Cerebral Perfusion; Heart failure; Depression; Cardiovascular disease; Cerebral blood flow velocity
8.  The Independent Association of Hypertension with Cognitive Function Among Older Adults with Heart Failure 
Journal of the neurological sciences  2012;323(1-2):216-220.
Hypertension is the most common comorbidity among heart failure (HF) patients and has been independently linked with cognitive impairment. Cognitive impairment is prevalent among HF patients, though the extent to which hypertension contributes to cognitive function in this population is unclear.
116 HF patients (31.0% women, 67.68 ± 11.16 years) completed neuropsychological testing and impedance cardiography. History of physician diagnosed hypertension, along with other medical characteristics, was ascertained through a review of participants’ medical charts.
69.8% of the HF patients had a diagnostic history of hypertension. After adjustment for demographic and medical characteristics (i.e., cardiac index, medication status, and resting blood pressure), hypertension was independently associated with attention/executive function/psychomotor speed (ΔF(1,103) = 10.85, ΔR2 = .07, p < .01) and motor functioning (ΔF(1,103) = 4.46, ΔR2 = .04, p < .05). HF patients with a diagnosed history of hypertension performed worse in these domains than those without such history.
The current findings indicate that diagnostic history of hypertension is an important contributor to cognitive impairment in HF. Hypertension frequently precedes HF and future studies should examine whether sustained hypertension compromises cerebral autoregulatory mechanisms to produce brain damage and exacerbate cognitive impairment in this population.
PMCID: PMC3483380  PMID: 23026535
Cognitive function; cardiac index; heart failure; hypertension; blood pressure
9.  Cognitive Function and Treatment Adherence in Older Adults with Heart Failure 
Psychosomatic medicine  2012;74(9):965-973.
Treatment recommendation and guidelines for patients with heart failure (HF) can be complex, and past work has shown HF patients to demonstrate low rates of adherence to recommended health behaviors. While previous work has identified several medical, demographic, and psychosocial predictors of HF persons’ capacity to adhere to treatment recommendations, little is known about the contribution of cognitive impairment to reported treatment adherence in this population.
149 persons with HF (68.08 years; SD = 10.74) completed a brief fitness assessment and neuropsychological testing. Treatment adherence was assessed using the Heart Failure Compliance Questionnaire, a brief measure that asks participants to report their adherence to a variety of recommended health behaviors (i.e., medication management, diet, exercise, among others).
16.1% of participants reported poor overall adherence, with particularly high rates of non-adherence to dietary and exercise recommendations. Hierarchical regression analyses adjusting for possible confounds revealed reduced performance on attention (β = .26, p = .01), executive function (β = .18, p = .04), and language (β = .22, p = .01) were associated with poorer overall adherence. Follow-up analyses showed these cognitive domains were associated with behaviors such as keeping doctor appointments, medication management, and dietary recommendations (p < .05 for all).
The current findings demonstrate that cognitive function is an independent contributor to adherence in older adults with HF. Prospective studies that objectively measure treatment adherence are needed to clarify these findings and identify possible strategies to improve outcomes in this population.
PMCID: PMC3498588  PMID: 23115344
attention; executive function; heart failure; treatment adherence; cognitive impairment
10.  A New Measure of Interpersonal Exploitativeness 
Measures of exploitativeness evidence problems with validity and reliability. The present set of studies assessed a new measure [the Interpersonal Exploitativeness Scale (IES)] that defines exploitativeness in terms of reciprocity. In Studies 1 and 2, 33 items were administered to participants. Exploratory and Confirmatory Factor Analysis demonstrated that a single factor consisting of six items adequately assess interpersonal exploitativeness. Study 3 results revealed that the IES was positively associated with “normal” narcissism, pathological narcissism, psychological entitlement, and negative reciprocity and negatively correlated with positive reciprocity. In Study 4, participants competed in a commons dilemma. Those who scored higher on the IES were more likely to harvest a greater share of resources over time, even while controlling for other relevant variables, such as entitlement. Together, these studies show the IES to be a valid and reliable measure of interpersonal exploitativeness. The authors discuss the implications of these studies.
PMCID: PMC3665920  PMID: 23755031
exploitativeness; narcissism; measurement; reciprocity; social dilemma
11.  Latent state trait modeling of children’s cortisol at two points of the diurnal cycle 
Psychoneuroendocrinology  2011;37(2):249-255.
One challenge in examining stable individual differences in basal activity of the HPA axis is controlling for internally- or externally- based situational factors that lead to day to day variation in ambulatory cortisol. Disturbed basal activity is of particular interest in studies with children, for whom a dysregulated HPA axis may play an etiologic role in emotional or health outcomes. The purpose of this study was to determine whether trait vs. situationally specific sources of variation can be identified at different points of the diurnal cycle in children and if so, whether state and trait components vary according to time of measurement. Early morning and late evening salivary cortisol was collected from 164 children aged 7-11 years. Samples were collected 30 minutes after wakeup and 30 minutes before bedtime on 3 weekdays. State, trait, and error components of cortisol levels were assessed using a latent state trait model. Possible influences of sampling day and outlier treatment on parameter estimates were examined. The results showed that a latent trait factor superimposed on state residuals and measurement error was identified for both early morning and late evening cortisol. Model fit was excellent and criteria for invariance tests were met. Trait factors accounted for 41% and 57% of the variance in morning and evening cortisol, respectively. These findings suggest cortisol attributed to trait factors can be identified and are of substantial magnitude at both the peak and nadir of the diurnal cycle. Latent state trait modeling is a potentially useful tool in understanding the role of stable individual differences in cortisol levels for development and health.
PMCID: PMC3241873  PMID: 21752549
hypothalamic pituitary adrenocortical axis; cortisol; latent state trait model
12.  Obesity Interacts with Cerebral Hypoperfusion to Exacerbate Cognitive Impairment in Older Adults with Heart Failure 
Cerebral hypoperfusion accompanies heart failure (HF) and is associated with reduced cognitive performance. Obesity is prevalent in persons with HF and is also a likely contributor to cognitive function, as it has been independently linked to cognitive impairment in healthy individuals. The current study examined the association between obesity and cognitive performance among older adults with HF and whether obesity interacts with cerebral hypoperfusion to exacerbate cognitive impairment.
Patients with HF (n = 99, 67.46 ± 11.36 years of age) completed neuropsychological testing and impedance cardiography. Cerebral blood flow velocity (CBF-V) measured by transcranial Doppler sonography quantified cerebral perfusion and body mass index (BMI) operationalized obesity.
A hierarchical regression analysis showed that lower CBF-V was associated with reduced performance on tests of attention/executive function and memory. Elevated BMI was independently associated with reduced attention/executive function and language test performance. Notably, a significant interaction between CBF-V and BMI indicated that a combination of hypoperfusion and high BMI has an especially adverse influence on attention/executive function in HF patients.
The current findings suggest that cerebral hypoperfusion and obesity interact to impair cognitive performance in persons with HF. These results may have important clinical implications, as HF patients who are at high risk for cerebral hypoperfusion may benefit from weight reduction.
PMCID: PMC3507266  PMID: 23272007
Body mass index; Cerebral perfusion; Cognitive function; Heart failure; Obesity
13.  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.
PMCID: PMC3371669  PMID: 22701196
14.  Self-Harm and Suicide Attempts among High-Risk, Urban Youth in the U.S.: Shared and Unique Risk and Protective Factors 
The extent to which self-harm and suicidal behavior overlap in community samples of vulnerable youth is not well known. Secondary analyses were conducted of the “linkages study” (N = 4,131), a cross-sectional survey of students enrolled in grades 7, 9, 11/12 in a high-risk community in the U.S. in 2004. Analyses were conducted to determine the risk and protective factors (i.e., academic grades, binge drinking, illicit drug use, weapon carrying, child maltreatment, social support, depression, impulsivity, self-efficacy, parental support, and parental monitoring) associated with both self-harm and suicide attempt. Findings show that 7.5% of participants reported both self-harm and suicide attempt, 2.2% of participants reported suicide attempt only, and 12.4% of participants reported self-harm only. Shared risk factors for co-occurring self-harm and suicide attempt include depression, binge drinking, weapon carrying, child maltreatment, and impulsivity. There were also important differences by sex, grade level, and race/ethnicity that should be considered for future research. The findings show that there is significant overlap in the modifiable risk factors associated with self-harm and suicide attempt that can be targeted for future research and prevention strategies.
PMCID: PMC3315085  PMID: 22470286
self-harm; suicide attempt; youth; adolescents; U.S.; high-risk; school; cross-sectional
15.  Assessing Injuries with Proxies: Implications for Understanding Concurrent Relations and Behavioral Antecedents of Pediatric Injuries 
Objective To examine the implications of using proxies of medically attended injuries (minor injuries and close calls) for understanding concurrent relations among—and behavioral antecedents of—pediatric injuries. Methods Participants were 812 children from the NICHD Study of Early Child Care. Measures of externalizing behavior, maternal depression, SES, and the home environment were examined as prospective predictors of minor injuries, close calls, and medically attended injuries. Results Minor injuries and close calls were associated with medically attended injuries concurrently. Regression equations revealed different prospective predictors across the three outcome variables. Conclusions This study was the first to examine concurrent associations among minor injuries, close calls, and medically attended injuries. Prospective antecedents of each injury assessment were also examined. The present findings signify the importance of distinguishing between these different methods of assessing pediatric injury. The study also illustrated that different analytic strategies were needed to represent observed data of each outcome variable.
PMCID: PMC2910935  PMID: 19451172
injury; injury proxies; count outcomes

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