Ronald Cohen

University of Florida, Gainesville, Florida, United States

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Publications (64)185.23 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Obesity is associated with cognitive impairment, and bariatric surgery has been shown to improve cognitive functioning. Rapid improvements in glycemic control are common after bariatric surgery and likely contribute to these cognitive gains. We examined whether improvements in glucose regulation are associated with better cognitive function following bariatric surgery. A total of 85 adult bariatric surgery patients underwent computerized cognitive testing and fasting blood draw for glucose, insulin, and glycated hemoglobin (HbA1c) at baseline and 12 months postoperatively. Significant improvements in both cognitive function and glycemic control were observed among patients. After controlling for baseline factors, 12-month homeostatic model assessment of insulin resistance HOMA-IR predicted 12-month digits backward (β = -.253, p < .05), switching of attention-A (β = .156, p < .05), and switching of attention-B (β = -.181, p < .05). Specifically, as HOMA-IR decreased over time, working memory, psychomotor speed, and cognitive flexibility improved. Decreases in HbA1c were not associated with postoperative cognitive improvements. After controlling for baseline cognitive test performance, changes in body mass index (BMI) were also not associated with 12-month cognitive function. Small effects of improved glycemic control on improved aspects of attention and executive function were observed following bariatric surgery among severely obese individuals. Future research is needed to identify the underlying mechanisms for the neurocognitive benefits of these procedures.
    Journal of Clinical and Experimental Neuropsychology 04/2015; 37(4):1-12. DOI:10.1080/13803395.2015.1023264 · 2.16 Impact Factor
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    ABSTRACT: HIV-associated brain injury persists despite antiretroviral therapy (cART), but contributing factors remain poorly understood. We postulated that inflammation-associated biomarkers will be associated with cerebral injury on proton magnetic resonance spectroscopy (MRS) in chronically HIV-infected subjects. Five biomarkers were measured in 197 HIV-infected subjects: soluble CD14, MCP-1, IP-10, MIP-1β, and fractalkine. Levels of N-acetyl aspartate (NAA), Choline (Cho), Myoinositol (MI), Glutamate+Glutamine (Glx), and Creatine (Cr) were acquired in the midfrontal cortex (MFC), frontal white matter (FWM), and basal ganglia (BG). Predictive models were built via linear regression and the best models were chosen using the Akaike Information Criterion. Increases in plasma or CSF MCP-1 were associated with lower NAA/Cr in the MFC and BG while metabolite changes in the FWM for NAA/Cr, GlxCr and Cho/Cr were explained almost exclusively by a single factor, sCD14. Plasma and CSF levels of this factor were also significantly associated with Glx/Cr in MFC and BG. Higher CSF FKN was associated with higher NAA/Cr in BG. Best predictors for higher Cho/Cr in BG and MFC were CSF sCD14 and CSF MIP-1β. Plasma and CSF IP-10 were only associated with Cho/Cr in MFC. Of the three models that simultaneously accounted for both plasma and CSF, there were more associations between CSF biomarkers and MRS metabolites. Markers of inflammation and immune activation, in particular MCP-1 and sCD14, predominantly reflecting CNS sources, contribute to the persistence of brain injury in a metabolite and region dependent manner in chronically HIV-infected patients on stable cART.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 01/2015; 69(1). DOI:10.1097/QAI.0000000000000532 · 4.39 Impact Factor
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    ABSTRACT: Reduced physical activity (PA) may be one factor that contributes to cognitive decline and dementia in heart failure (HF). Yet, the longitudinal relationship between PA and cognition in HF is poorly understood due to limitations of past work, including single time assessments of PA. This is the first study to examine changes in objectively measured PA and cognition over time in HF. At baseline and 12-weeks, 57 HF patients completed psychosocial self-report measures, a neuropsychological battery, and wore an accelerometer for seven days. At baseline, HF patients spent an average of 597.83 (SD = 75.91) minutes per day sedentary. Steps per day declined from baseline to the 12-week follow-up; there was also a trend for declines in moderate-vigorous PA. Regression analyses controlling for sex, HF severity, and depressive symptoms showed that decreases in light (p = 0.08) and moderate-vigorous (p = 0.04) daily PA emerged as strong predictors of declines in attention/executive function over the 12-week period, but not memory or language. Reductions in daily PA predicted acute decline in attention/executive function in HF, but not memory or language. Modifications to daily PA may attenuate cognitive decline and prospective studies are needed to test this possibility. Copyright © 2014 Elsevier Inc. All rights reserved.
    Journal of Cardiac Failure 01/2015; DOI:10.1016/j.cardfail.2014.12.010 · 3.07 Impact Factor
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    ABSTRACT: Bariatric surgery is associated with improved cognitive function, but the mechanisms underlying these gains remain poorly understood. Disturbed leptin and ghrelin systems are common in obese individuals and are associated with impaired cognitive function in other samples. Bariatric surgery has been shown to improve serum leptin and ghrelin levels, and these changes may underlie postoperative cognitive improvements. Eighty-four patients completed a computerized cognitive test battery prior to bariatric surgery and at 12 months postoperatively. Participants also submitted to an 8-hour fasting blood draw to quantify serum leptin and ghrelin concentrations at these same time points. Baseline cognitive impairments and disturbed leptin and ghrelin levels improved at the 12-month follow-up compared to presurgery. Higher leptin levels were associated with worse attention/executive function at baseline; no such findings emerged for ghrelin. Regression analyses controlling for baseline factors and demographic characteristics showed that both decreased leptin and increased ghrelin following surgery was associated with better attention/executive function at the 12-month follow-up. These effects diminished after controlling for the postoperative change in body mass index (BMI); however, BMI change did not predict 12-month cognitive function. Improvements in leptin and ghrelin levels following bariatric surgery appear to contribute to postoperative cognitive benefits. These gains may involve multiple mechanisms, such as reduced inflammation and improved glycemic control. Future studies that employ neuroimaging are needed to clarify the underlying mechanisms and determine whether the effects of bariatric surgery on leptin and ghrelin levels can attenuate adverse brain changes and/or risk of dementia in severely obese individuals.
    Journal of Clinical Neurology 01/2015; 11(1):48-56. DOI:10.3988/jcn.2015.11.1.48 · 1.81 Impact Factor
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    ABSTRACT: Heart failure (HF) patients are at risk for structural brain changes due to cerebral hypoperfusion. Past work shows obesity is linked with reduced cerebral blood flow and associated with brain atrophy in healthy individuals, although its effects on the brain in HF are unclear. This study examined the association among body mass index (BMI), cerebral perfusion, and brain volume in HF patients. Eighty HF patients underwent transcranial Doppler sonography to quantify cerebral blood flow velocity of the middle cerebral artery (CBF-V of the MCA) and brain magnetic resonance imaging (MRI) to quantify total brain, total and subcortical gray matter, white matter volume, and white matter hyperintensities. Body mass index (BMI) operationalized weight status. Nearly 45% of HF patients exhibited a BMI consistent with obesity. Regression analyses adjusting for medical variables, demographic characteristics, and CBF-V of the MCA, showed increased BMI was associated with reduced white matter volume (p <.05). BMI also interacted with cerebral perfusion to impact total gray matter volume, but this pattern did not emerge for any other MRI indices (p < 0.05). Our findings suggest increased BMI negatively affects brain volume in HF, and higher BMI interacts with cerebral perfusion to impact gray matter volume. The mechanisms for these findings remain unclear and likely involve multiple physiological processes. Prospective studies are needed to elucidate the exact pattern and rates of brain changes in obese HF persons.
    12/2014; 1(1):4. DOI:10.1186/2052-9538-1-4
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    ABSTRACT: Heart failure patients require assistance with instrumental activities of daily living in part because of the high rates of cognitive impairment in this population. Structural brain insult (eg, reduced gray matter volume) is theorized to underlie cognitive dysfunction in heart failure, although no study has examined the association among gray matter, cognition, and instrumental activities of daily living in heart failure. The aim of this study was to investigate the associations among gray matter volume, cognitive function, and functional ability in heart failure. A total of 81 heart failure patients completed a cognitive test battery and the Lawton-Brody self-report questionnaire to assess instrumental activities of daily living. Participants underwent magnetic resonance imaging to quantify total gray matter and subcortical gray matter volume. Impairments in instrumental activities of daily living were common in this sample of HF patients. Regression analyses controlling for demographic and medical confounders showed that smaller total gray matter volume predicted decreased scores on the instrumental activities of daily living composite, with specific associations noted for medication management and independence in driving. Interaction analyses showed that reduced total gray matter volume interacted with worse attention/executive function and memory to negatively impact instrumental activities of daily living. Smaller gray matter volume is associated with greater impairment in instrumental activities of daily living in persons with heart failure, possibly via cognitive dysfunction. Prospective studies are needed to clarify the utility of clinical correlates of gray matter volume (eg, cognitive dysfunction) in identifying heart failure patients at risk for functional decline and determine whether interventions that target improved brain and cognitive function can preserve functional independence in this high-risk population.
    The Journal of cardiovascular nursing 11/2014; Publish Ahead of Print. DOI:10.1097/JCN.0000000000000218 · 1.81 Impact Factor
  • Journal of the American Geriatrics Society 11/2014; 62(11). DOI:10.1111/jgs.13123 · 4.22 Impact Factor
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    ABSTRACT: 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.
    Journal of Clinical and Experimental Neuropsychology 10/2014; 36(9):1-11. DOI:10.1080/13803395.2014.957167 · 2.16 Impact Factor
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    ABSTRACT: Objective: Bariatric surgery is associated with improved cognitive function, though the mechanisms are unclear. Elevated inflammation is common in obesity and associated with impaired cognition. Inflammation decreases after bariatric surgery, implicating it as a possible mechanism for cognitive improvement. The objective of this study was to examine whether reduced inflammation is a possible mechanism for post-operative cognitive improvement in bariatric surgery patients. Methods: Participants were 77 bariatric surgery patients who completed cognitive testing before surgery and one year post-surgery. Cognitive domains assessed were attention/executive function, language, and memory. High-sensitivity C-reactive protein (hs-CRP) was assessed at both time points. Results: Patients exhibited pre-operative cognitive impairment, though attention/ executive (M±SDbaseline= 53.57 ± 8.68 vs. M±SDfollow-up= 60.32 ± 8.19) and memory (M±SDbaseline= 44.96 ± 7.98 vs. M±SDfollow-up= 51.55 ± 8.25) improved one year post-surgery. CRP was elevated at baseline and fell into the normative range post-surgery (M±SDbaseline= 0.9 ± 0.7 vs. M±SDfollow-up= 0.2 ± 0.3 mg/dL). Pre-operative CRP was not associated with baseline cognitive function (β-values = -0.10 to 0.02) and changes in CRP also did not correspond to changes in cognition post-surgery (β-values = 0.02 to β = 0.11; ps >0.05 for all domains). A trend was detected for smaller improvements in memory among participants with elevated baseline CRP (>0.30 mg/dL) versus those with normal levels (Group x Time: p=0.083). Conclusions: Improvements in hs-CRP were not associated with post-operative cognitive benefits. Future studies are needed to explore other inflammatory markers and potential mechanisms of cognitive improvement after bariatric surgery, including improved glycemic control and neurohormone changes.
    Psychosomatic Medicine 10/2014; in press. DOI:10.1097/PSY.0000000000000125 · 4.09 Impact Factor
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    ABSTRACT: Obesity-associated cognitive impairments may be partially reversible through bariatric surgery. Depression, a prevalent comorbidity in bariatric surgery candidates, is linked with cognitive impairment and poorer surgical outcomes in other populations. No study has examined the effects of pre-operative depression on cognitive changes in bariatric surgery patients. Sixty-seven bariatric surgery patients completed a computerized cognitive test battery prior to surgery and 12 months post-operatively. The structured clinical interview for the DSM-IV Axis I disorders assessed major depressive disorder (MDD). Pre-surgery history of MDD was found in 47.8% of patients, but was not associated with greater baseline cognitive impairments. Repeated measures revealed improved cognitive abilities 12 months after surgery. Pre-surgery history of MDD did not influence post-operative cognitive function. Pre-operative history of MDD did not limit post-operative cognitive improvements. Larger studies with extended follow-ups are needed to clarify our findings and identify factors (e.g. older age) that may modify cognitive changes following surgery.
    Psychology Health and Medicine 09/2014; 20(7):1-12. DOI:10.1080/13548506.2014.959531 · 1.53 Impact Factor
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    ABSTRACT: Evidence suggests that both obesity and binge eating disorder (BED) may be associated with deficits in cognitive functioning. The purpose of this study was to examine whether a lifetime history of BED would be associated with changes in several domains of cognitive functioning (attention, executive function, language, and memory) following bariatric surgery. Participants were 68 bariatric surgery patients who completed a computerized battery of cognitive tests within 30 days prior to undergoing surgery and again at a 12-Month postoperative follow-up. Results revealed that on the whole, participants displayed improvements from baseline to follow-up in attention, executive function, and memory, even after controlling for diagnostic history of depression; no changes were observed for language. However, individuals with and without a history of BED did not differ in changes in body mass index or in the degree of improvement in cognitive functioning from baseline to follow-up. Such results suggest that a history of BED does not influence changes in cognitive functioning following bariatric surgery. Future research will be needed to further clarify the role of BED in predicting cognitive function over time.
    Journal of Psychiatric Research 08/2014; 59. DOI:10.1016/j.jpsychires.2014.08.004 · 4.09 Impact Factor
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    ABSTRACT: 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.
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    ABSTRACT: Background: The mechanisms for improved cognitive function post-bariatric surgery are not well understood. Markers of kidney and liver function (i.e., cystatin C and alkaline phosphatase (ALP)) are elevated in obese individuals and associated with poor neurocognitive outcomes in other samples. Bariatric surgery can improve cystatin C and ALP levels, but no study has examined whether such changes correspond to post-operative cognitive benefits. Methods: 78 bariatric surgery patients completed a computerized cognitive test battery prior to and 12-months after surgery. All participants underwent an eight-hour fasting blood draw to quantify cystatin C and ALP concentrations. Results: Cognitive function improved after surgery. Cystatin C levels decreased at the 12-month follow-up; however, no changes were found in ALP concentrations. At baseline, higher cystatin C levels predicted worse attention/executive function, but no such effects emerged for ALP. Regression analyses controlling for possible medical and demographic confounds and baseline factors revealed that decreased ALP levels following surgery predicted better attention/executive function and memory abilities. Post-surgery changes in cystatin C did not correspond to cognitive improvements. Conclusions: Decreased ALP levels predicted better cognition following bariatric surgery, suggesting improved liver function as a possible mechanism of post-operative cognitive benefits. Future studies with neuroimaging and longer follow-up periods are needed to determine whether bariatric surgery can decrease risk for adverse brain changes and dementia in severely obese persons via improved metabolic function.
    Journal of the Neurological Sciences 07/2014; 345(1-2). DOI:10.1016/j.jns.2014.07.037 · 2.26 Impact Factor
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    ABSTRACT: Cognitive impairment is common in heart failure. Obesity is a known risk factor for cognitive dysfunction in heart failure, though the mechanisms remain unclear. Obesity increases risk for conditions like hypertension and type 2 diabetes mellitus (T2DM) as well as poor fitness levels, and this may serve as one possible pathway accounting for association between obesity and cognitive dysfunction. We used structural equation modeling to test whether the combination of hypertension, T2DM, and reduced fitness mediate the association between obesity and cognitive dysfunction. Two hundred heart failure patients completed neuropsychological testing and a physical fitness assessment. Hypertension and T2DM were ascertained via self-report and medical records. Body mass index (BMI) was calculated. Forty-three percent of the sample was obese. Hypertension (70%) and T2DM (36%) were common, and fitness levels were reduced. The structural equation model with these factors as mediators between BMI and cognitive function demonstrated excellent fit (comparative fit index = 0.98; root mean-square error of approximations = 0.03). Higher BMI correlated with hypertension, T2DM, and poorer fitness. Each of these factors predicted worse cognition. Models that isolated medical comorbidities and physical fitness as the mediator were weaker than the full model. Increased risk for medical comorbidities and reduced fitness levels helped to explain the negative effects of obesity on cognitive dysfunction in heart failure. Prospective studies should confirm this pattern and examine how weight loss benefits cognitive function in heart failure.
    European Journal of Cardiovascular Nursing 05/2014; 14(4). DOI:10.1177/1474515114535331 · 1.83 Impact Factor
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    ABSTRACT: Cerebral hypoperfusion is common in heart failure (HF) and believed to underlie poor neurocognitive outcomes in this population. Up to 42% of HF patients also exhibit depressive symptomatology that may stem from reduced cerebral blood flow. However, no study has examined this possibility or whether reduced brain perfusion increases risk for future cognitive dysfunction in older adults with HF. One hundred HF patients underwent transcranial Doppler ultrasonagraphy to quantify global cerebral blood flow velocity (CBF-V) and were administered a cognitive test battery to assess global cognition, attention/executive function, and memory abilities. All participants then completed the Beck Depression Inventory-II to assess depressive symptomatology. These procedures were performed at baseline and at 12-month follow-up. Repeated measures revealed that CBF-V declined over the 12-month period. Regression analyses showed that reduced baseline CBF-V predicted worse performances in attention/executive function (p < 0.05 for all) and a trend for memory (p = 0.09) in addition to greater depressive symptomatology (p < 0.05) at the 12-month follow-up, even after controlling for baseline factors and medical and demographic variables. Cerebral perfusion declined over time and was associated with poorer cognitive function and greater depressive symptoms at a 1-year follow-up in HF. Prospective studies with long-term follow-ups that employ neuroimaging are needed to examine whether cognitive dysfunction and depression in HF stem from the adverse effects of cerebral hypoperfusion on the cerebral structure. Copyright © 2013 John Wiley & Sons, Ltd.
    International Journal of Geriatric Psychiatry 04/2014; 29(4). DOI:10.1002/gps.4023 · 3.09 Impact Factor
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    ABSTRACT: Background Bariatric surgery is associated with cognitive benefits, but the nature of such gains may be variable across demographically and clinically diverse persons. Older adults achieve less weight loss and resolution of fewer medical comorbidities after surgery compared to younger patients, and are also at heightened risk for nutritional deficiencies. However, no study has examined the influence of age on cognitive improvements after bariatric surgery. Objective To determine the effects of age on cognitive function post-bariatric surgery. Setting Hospital. Methods 95 participants enrolled in the Longitudinal Assessment for Bariatric Surgery completed a computerized cognitive test battery prior to bariatric surgery and at 12-weeks, and 12-months post-operatively. Results Baseline cognitive impairments were common. Significant improvements were found in attention/executive function and memory abilities 12-weeks and 12-months after surgery. Age was not associated with baseline cognitive test performance. Separate multivariable regression analyses controlling for baseline attention/executive function and memory also showed that age was not a significant predictor of 12-week or 12-month performances in these domains (p > 0.05 for all). Conclusions The current study provides preliminary evidence suggesting that older age does not preclude post-bariatric surgery cognitive benefits. Prospective studies in more age diverse samples (i.e., up to 70 years) are needed to determine whether bariatric surgery can reduce risk of age-related neurological conditions like Alzheimer’s disease and stroke.
    Surgery for Obesity and Related Diseases 04/2014; 10(6). DOI:10.1016/j.soard.2014.04.005 · 4.94 Impact Factor
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    ABSTRACT: 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.
    Journal of the neurological sciences 04/2014; 339(1-2). DOI:10.1016/j.jns.2014.02.008 · 2.26 Impact Factor
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    ABSTRACT: Abstract Cognitive impairment is common in severe obesity. Lack of physical activity is a likely contributor to impairment in this population, as many obese persons are inactive and physical activity has been positively and independently associated with cognitive function in healthy and medically-ill samples. This study investigated whether physical activity, measured by self-report of aerobic physical activity in 85 bariatric surgery candidates, was associated with cognitive function. A subset of 31 participants also completed objective activity monitoring. Steps/day and high-cadence minutes/week, representative of ambulatory moderate to vigorous physical activity (MVPA), were calculated. Approximately one quarter of participants self-reported at least 30 minutes/day of aerobic MVPA, at least 5 days per week. Median steps/day was 7949 (IQR = 4572) and median MVPA min/week was 105 (IQR = 123). Cognitive deficits were found in 32% of participants (29% memory, 10% executive function, 13% language, 10% attention). Controlling for demographic and medical factors, self-reported aerobic physical activity was weakly correlated with lower attention (r = -.21, p = .04) and executive function (r = -.27, p < .01) and both self-reported aerobic physical activity and objectively-determined MVPA min/week were negatively correlated with memory (r = -.20, p = .04; r = -.46; p = .02, respectively). No other correlations between physical activity measures and cognitive function were significant. Contrary to expectations, greater levels of physical activity were not associated with better cognitive functioning. Such findings encourage future studies to clarify the association among cognitive function and physical activity in obese persons.
    The International journal of neuroscience 02/2014; 124(12). DOI:10.3109/00207454.2014.895344 · 1.53 Impact Factor
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    ABSTRACT: Objective: Nearly 6 million Americans have heart failure (HF), up to 80% of which exhibit cognitive deficits on testing. Physical inactivity is common in HF, yet little is known about the possible contribution of physical inactivity to cognitive dysfunction in this population. Method: Older adults with HF (N = 93; Mage = 68.5 years, 33.7% women) completed neuropsychological testing, as well as cardiac and physical activity assessment as part of a larger protocol. HF severity was measured via impedance cardiography. Physical activity was assessed via an Actigraph accelerometer and operationalized using daily step count and time engaged in moderate-vigorous activity (minutes/day). Results: Linear regression analyses controlling for sex, high blood pressure, diabetes, depressive symptomatology, and HF severity showed that greater physical activity (both step count and minutes spent in moderate-vigorous activity) was associated with better executive function/attention, processing speed, and scores on a screening measure of cognition. Conclusions: These findings indicate that physical activity is an independent predictor of cognitive function in persons with HF. Future work is needed to clarify the mechanisms by which physical activity benefits cognitive function in HF and determine whether interventions to promote physical activity can attenuate cognitive decline over time. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
    Health Psychology 01/2014; 33(11). DOI:10.1037/hea0000039 · 3.95 Impact Factor
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    ABSTRACT: Objective: Obesity is as an independent risk factor for poor neurocognitive outcomes, including Alzheimer's disease. Bariatric surgery has recently been shown to result in improved memory at 12-weeks post-operatively. However, the long-term effects of bariatric surgery on cognitive function remain unclear. Design and Methods: 86 individuals (63 bariatric surgery patients, 23 obese controls) were recruited from a prospective study examining the neurocognitive effects of bariatric surgery. All participants completed self-report measurements and a computerized cognitive test battery prior to surgery and at 12-week and 24-month follow-up; obese controls completed measures at equivalent time points. Results: Bariatric surgery patients exhibited high rates of pre-operative cognitive impairments in attention, executive function, memory, and language. Relative to obese controls, repeated measures ANOVA showed improvements in memory from baseline to 12-weeks and 24-months post-operatively (p <.05). Regression analyses controlling for baseline factors revealed that a lower BMI at 24-months demonstrated a trend toward significance for improved memory (β = -.30, p =.075). Conclusion: These findings suggest that cognitive benefits of bariatric surgery may extend to 24-months post-operatively. Larger prospective studies with extended follow-up periods are needed to elucidate whether bariatric surgery decreases risk for cognitive decline and possibly the development of dementia.
    Obesity 01/2014; 22(1). DOI:10.1002/oby.20494 · 4.39 Impact Factor

Publication Stats

749 Citations
185.23 Total Impact Points

Institutions

  • 2013–2015
    • University of Florida
      • Institute on Aging
      Gainesville, Florida, United States
    • McKnight Brain Institute
      Gainesville, Florida, United States
  • 2014
    • European Society of Cardiology
      Biot, Provence-Alpes-Côte d'Azur, France
    • Kent State University
      • Department of Psychology
      Кент, Ohio, United States
  • 2005–2014
    • Alpert Medical School - Brown University
      • Department of Psychiatry and Human Behavior
      Providence, Rhode Island, United States
  • 2008–2013
    • Brown University
      • Department of Psychiatry and Human Behavior
      Providence, Rhode Island, United States
  • 2011–2012
    • Rhode Island Hospital
      Providence, Rhode Island, United States
  • 2009
    • Harvard Medical School
      • Department of Radiology
      Boston, Massachusetts, United States
  • 2001–2002
    • Providence Hospital
      Mobile, Alabama, United States