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1.
Brain functions and cognition on transient insulin deprivation in type 1 diabetes.
Creo, AL, Cortes, TM, Jo, HJ, Huebner, AR, Dasari, S, Tillema, JM, Lteif, AN, Klaus, KA, Ruegsegger, GN, Kudva, YC, et al
JCI insight. 2021;(5)
Abstract
BACKGROUNDType 1 diabetes (T1D) is a risk factor for dementia and structural brain changes. It remains to be determined whether transient insulin deprivation that frequently occurs in insulin-treated individuals with T1D alters brain function.METHODSWe therefore performed functional and structural magnetic resonance imaging, magnetic resonance spectroscopy, and neuropsychological testing at baseline and following 5.4 ± 0.6 hours of insulin deprivation in 14 individuals with T1D and compared results with those from 14 age-, sex-, and BMI-matched nondiabetic (ND) participants with no interventions.RESULTSInsulin deprivation in T1D increased blood glucose, and β-hydroxybutyrate, while reducing bicarbonate levels. Participants with T1D showed lower baseline brain N-acetyl aspartate and myo-inositol levels but higher cortical fractional anisotropy, suggesting unhealthy neurons and brain microstructure. Although cognitive functions did not differ between participants with T1D and ND participants at baseline, significant changes in fine motor speed as well as attention and short-term memory occurred following insulin deprivation in participants with T1D. Insulin deprivation also reduced brain adenosine triphosphate levels and altered the phosphocreatine/adenosine triphosphate ratio. Baseline differences in functional connectivity in brain regions between participants with T1D and ND participants were noted, and on insulin deprivation further alterations in functional connectivity between regions, especially cortical and hippocampus-caudate regions, were observed. These alterations in functional connectivity correlated to brain metabolites and to changes in cognition.CONCLUSIONTransient insulin deprivation therefore caused alterations in executive aspects of cognitive function concurrent with functional connectivity between memory regions and the sensory cortex. These findings have important clinical implications, as many patients with T1D inadvertently have periods of transient insulin deprivation.TRIAL REGISTRATIONClinicalTrials.gov NCT03392441.FUNDINGClinical and Translational Science Award (UL1 TR002377) from the National Center for Advancing Translational Science; NIH grants (R21 AG60139 and R01 AG62859); the Mayo Foundation.
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Assessment of cognitive and psychomotor impairment, subjective effects, and blood THC concentrations following acute administration of oral and vaporized cannabis.
Spindle, TR, Martin, EL, Grabenauer, M, Woodward, T, Milburn, MA, Vandrey, R
Journal of psychopharmacology (Oxford, England). 2021;(7):786-803
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Abstract
BACKGROUND Cannabis legalization is expanding, but there are no established methods for detecting cannabis impairment. AIM: Characterize the acute impairing effects of oral and vaporized cannabis using various performance tests. METHODS Participants (N = 20, 10 men/10 women) who were infrequent cannabis users ingested cannabis brownies (0, 10, and 25 mg Δ-9-tetrahydrocannabinol, THC) and inhaled vaporized cannabis (0, 5, and 20 mg THC) in six double-blind outpatient sessions. Cognitive/psychomotor impairment was assessed with a battery of computerized tasks sensitive to cannabis effects, a novel test (the DRiving Under the Influence of Drugs, DRUID®), and field sobriety tests. Blood THC concentrations and subjective drug effects were evaluated. RESULTS Low oral/vaporized doses did not impair cognitive/psychomotor performance relative to placebo but produced positive subjective effects. High oral/vaporized doses impaired cognitive/psychomotor performance and increased positive and negative subjective effects. The DRUID® was the most sensitive test to cannabis impairment, as it detected significant differences between placebo and active doses within both routes of administration. Women displayed more impairment on the DRUID® than men at the high vaporized dose only. Field sobriety tests showed little sensitivity to cannabis-induced impairment. Blood THC concentrations were far lower after cannabis ingestion versus inhalation. After inhalation, blood THC concentrations typically returned to baseline well before pharmacodynamic effects subsided. CONCLUSIONS Standard approaches for identifying impairment due to cannabis exposure (i.e. blood THC and field sobriety tests) have severe limitations. There is a need to identify novel biomarkers of cannabis exposure and/or behavioral tests like the DRUID® that can reliably and accurately detect cannabis impairment at the roadside and in the workplace.
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Recruitment and Baseline Characteristics of Participants in the AgeWell.de Study-A Pragmatic Cluster-Randomized Controlled Lifestyle Trial against Cognitive Decline.
Röhr, S, Zülke, A, Luppa, M, Brettschneider, C, Weißenborn, M, Kühne, F, Zöllinger, I, Samos, FZ, Bauer, A, Döhring, J, et al
International journal of environmental research and public health. 2021;(2)
Abstract
Targeting dementia prevention, first trials addressing multiple modifiable risk factors showed promising results in at-risk populations. In Germany, AgeWell.de is the first large-scale initiative investigating the effectiveness of a multi-component lifestyle intervention against cognitive decline. We aimed to investigate the recruitment process and baseline characteristics of the AgeWell.de participants to gain an understanding of the at-risk population and who engages in the intervention. General practitioners across five study sites recruited participants (aged 60-77 years, Cardiovascular Risk Factors, Aging, and Incidence of Dementia/CAIDE dementia risk score ≥ 9). Structured face-to-face interviews were conducted with eligible participants, including neuropsychological assessments. We analyzed group differences between (1) eligible vs. non-eligible participants, (2) participants vs. non-participants, and (3) between intervention groups. Of 1176 eligible participants, 146 (12.5%) dropped out before baseline; the study population was thus 1030 individuals. Non-participants did not differ from participants in key sociodemographic factors and dementia risk. Study participants were M = 69.0 (SD = 4.9) years old, and 52.1% were women. The average Montreal Cognitive Assessment/MoCA score was 24.5 (SD = 3.1), indicating a rather mildly cognitively impaired study population; however, 39.4% scored ≥ 26, thus being cognitively unimpaired. The bandwidth of cognitive states bears the interesting potential for differential trial outcome analyses. However, trial conduction is impacted by the COVID-19 pandemic, requiring adjustments to the study protocol with yet unclear methodological consequences.
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Effect of Advanced Glycation End Products on Cognition in Older Adults with Type 2 Diabetes: Results from a Pilot Clinical Trial.
Lotan, R, Ganmore, I, Livny, A, Itzhaki, N, Waserman, M, Shelly, S, Zacharia, M, Moshier, E, Uribarri, J, Beisswenger, P, et al
Journal of Alzheimer's disease : JAD. 2021;(4):1785-1795
Abstract
BACKGROUND Dietary advanced glycation end-products (AGEs) are linked to cognitive decline. However, clinical trials have not tested the effect of AGEs on cognition in older adults. OBJECTIVE The aim of the current pilot trial was to examine the feasibility of an intervention to reduce dietary AGEs on cognition and on cerebral blood flow (CBF). METHODS The design is a pilot randomized controlled trial of dietary AGEs reduction in older adults with type 2 diabetes. Seventy-five participants were randomized to two arms. The control arm received standard of care (SOC) guidelines for good glycemic control; the intervention arm, in addition to SOC guidelines, were instructed to reduce their dietary AGEs intake. Global cognition and CBF were assessed at baseline and after 6 months of intervention. RESULTS At baseline, we found a reverse association between AGEs and cognitive functioning, possibly reflecting the long-term toxicity of AGEs on the brain. There was a significant improvement in global cognition at 6 months in both the intervention and SOC groups which was more prominent in participants with mild cognitive impairment. We also found that at baseline, higher AGEs were associated with increased CBF in the left inferior parietal cortex; however, 6 months of the AGEs lowering intervention did not affect CBF levels, despite lowering AGEs exposure in blood. CONCLUSION The current pilot trial focused on the feasibility and methodology of intervening through diet to reduce AGEs in older adults with type 2 diabetes. Our results suggest that participants with mild cognitive impairment may benefit from an intensive dietary intervention.
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Evaluation of Available Cognitive Tools Used to Measure Mild Cognitive Decline: A Scoping Review.
Chun, CT, Seward, K, Patterson, A, Melton, A, MacDonald-Wicks, L
Nutrients. 2021;(11)
Abstract
Cognitive decline is a broad syndrome ranging from non-pathological/age-associated cognitive decline to pathological dementia. Mild cognitive impairment MCI) is defined as the stage of cognition that falls between normal ageing and dementia. Studies have found that early lifestyle interventions for MCI may delay its pathological progression. Hence, this review aims to determine the most efficient cognitive tools to discriminate mild cognitive decline in its early stages. After a systematic search of five online databases, a total of 52 different cognitive tools were identified. The performance of each tool was assessed by its psychometric properties, administration time and delivery method. The Montreal Cognitive Assessment (MoCA, n = 15), the Mini-Mental State Examination (MMSE, n = 14) and the Clock Drawing Test (CDT, n = 4) were most frequently cited in the literature. The preferable tools with all-round performance are the Six-item Cognitive Impairment Test (6CIT), MoCA (with the cut-offs of ≤24/22/19/15.5), MMSE (with the cut-off of ≤26) and the Hong Kong Brief Cognitive Test (HKBC). In addition, SAGE is recommended for a self-completed survey setting whilst a 4-point CDT is quick and easy to be added into other cognitive assessments. However, most tools were affected by age and education levels. Furthermore, optimal cut-off points need to be cautiously chosen while screening for MCI among different populations.
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Greek High Phenolic Early Harvest Extra Virgin Olive Oil Reduces the Over-Excitation of Information-Flow Based on Dominant Coupling Mode (DoCM) Model in Patients with Mild Cognitive Impairment: An EEG Resting-State Validation Approach.
Dimitriadis, SI, Lyssoudis, C, Tsolaki, AC, Lazarou, E, Kozori, M, Tsolaki, M
Journal of Alzheimer's disease : JAD. 2021;(1):191-207
Abstract
BACKGROUND Extra virgin olive oil (EVOO) constitutes a natural compound with high protection over cognitive function that could positively alter brain dynamics and the mixture of within and between-frequency connectivity. OBJECTIVE The balance of cross-frequency coupling over within-frequency coupling can build a nonlinearity index (NI) that encapsulates the over-excitation of information flow between brain areas and across experimental time. The present study investigated for the very first time how the Greek High Phenolic Early Harvest Extra Virgin Olive Oil (HP-EH-EVOO) versus Moderate Phenolic (MP-EVOO) and Mediterranean Diet (MeDi) intervention in people with mild cognitive impairment (MCI) could affect their spontaneous EEG dynamic connectivity. METHODS Forty-three subjects (14 in MeDi, 16 in MP-EVOO, and 13 in HP-EH-EVOO) followed an EEG resting-state recording session (eyes-open and closed) before and after the treatment. Following our dominant coupling mode model, we built a dynamic integrated dynamic functional connectivity graph that tabulates the functional strength and the dominant coupling mode model of every pair of brain areas. RESULTS Signal spectrum within 1-13 Hz and theta/beta ratio have decreased in the HP-EH-EVOO group in the eyes-open condition. The intervention improved the FIDoCM across groups and conditions but was more prominent in the HP-EH-EVOO group (p < 0.001). Finally, we revealed a significant higher post-intervention reduction of NI (ΔNITotal and α) for the HP-EH-EVOO compared to the MP-EVOO and MeDi groups (p < 0.0001). CONCLUSION Long-term intervention with HP-EH-EVOO reduced the over-excitation of information flow in spontaneous brain activity and altered the signal spectrum of EEG rhythms.
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Association of anthropometric and nutrition status indicators with cognitive functions in centenarians.
Tai, P, Yang, S, Liu, W, Wang, S, Chen, K, Jia, W, Han, K, Liu, M, He, Y
Clinical nutrition (Edinburgh, Scotland). 2021;(4):2252-2258
Abstract
BACKGROUND & AIMS How anthropometric and nutrition status indicators relate to cognitive function in the oldest old adults is an issue that needs to be explored. This study aimed to analyze the association of parameters and nutrition status indicators (waist circumference, BMI, calf circumference, and waist-calf circumference ratio [WCR]) with cognitive functions in centenarians. METHODS A cross-sectional observational study was conducted with the full sample of 1002 centenarians from Hainan. The mini-mental state examination (MMSE) was used to identify cognitive impairment. Multiple logistic regression analysis was used to examine the strength of association between each anthropometric index and the risk of cognitive impairment or severe cognitive impairment identified by MMSE. Locally Weighted Scatterplot Smoothing (LOWESS) curve was used to visualize the linear or non-linear relationship of each pair. RESULTS The risk of cognitive impairment identified by MMSE for centenarians was reduced by 12% for every 1 cm thickening of the calf circumference (OR = 0.88, 95% CI: 0.81-0.95) and the increase in each unit of WCR increased cognitive impairment the risk by 1.60 times (OR = 2.60, 95% CI: 1.31-5.13) after adjusting for demographic characteristics (i.e., gender, age, ethnicity, marital status, education level, and type of residence) and lifestyle (i.e., smoking, drinking, and exercise) related variables. CONCLUSIONS Results suggest that calf circumference is negatively associated with the risk of cognitive impairment identified by MMSE in centenarians. Older adults with lower calf circumference should pay attention to their cognitive function.
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Prediction of cognitive response to surgery in elderly patients with primary hyperparathyroidism.
Koman, A, Bränström, R, Pernow, Y, Bränström, R, Nilsson, IL
BJS open. 2021;(2)
Abstract
BACKGROUND Primary hyperparathyroidism (pHPT) can be associated with potentially reversible cognitive impairment, which is occasionally mistaken for natural ageing and dementia. The aim was to evaluate short-term medical normalization of hypercalcaemia in surgical decision-making for elderly patients with mild cognitive deficiency. METHODS Patients with pHPT were included in a prospective observational study. A test panel including the Montreal Cognitive Assessment (MoCA) and validated tools for estimation of psychological status (Hospital Anxiety and Depression Scale, HADS), and muscle strength (timed-stands test, TST) was applied at baseline, after 4 weeks of calcimimetic treatment, and after parathyroidectomy. Mild cognitive impairment was defined by a MoCA score below 26. A longitudinal increase in MoCA score of at least 2 points 6 months after surgery was considered clinically meaningful. RESULTS Of 110 patients who underwent testing, 35 aged 50 years or more were identified to have mild cognitive dysfunction, including 19 who were aged at least 70 years (median MoCA score 23, i.q.r. 21-24). Calcimimetic treatment resulted in normalization of calcium levels, and improvements in MoCA and HADS scores, and TST time. Normal MoCA scores (at least 26) were reached in 17 patients by 6 months after surgery, of whom 10 were aged 70 years or older. Long-term increase in MoCA score correlated with the decrease in ionized calcium concentration (r = -0.536, P = 0.022). Baseline calcium concentration and improvement in MoCA with calcimimetic treatment were identified as independent predictors of favourable outcome after parathyroidectomy. CONCLUSION Medical normalization of hypercalcaemia can aid in predicting outcome after parathyroidectomy.
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Impact of Fatty Acid Supplementation on Cognitive Performance among United States (US) Military Officers: The Ranger Resilience and Improved Performance on Phospholipid-Bound Omega-3's (RRIPP-3) Study.
Marriott, BP, Turner, TH, Hibbeln, JR, Newman, JC, Pregulman, M, Malek, AM, Malcolm, RJ, Burbelo, GA, Wismann, JW
Nutrients. 2021;(6)
Abstract
Studies have assessed omega-3 fatty acids and cognitive decline among older adults and cognitive development among children, although less is known about cognitive or neurological effects among young adults. We examined whether omega-3 supplementation from krill oil could improve cognition and resilience among young military officers compared to a control. This double-blind, placebo-controlled trial enrolled 555 officers (mean age 23.4 ± 2.8, 98.6% male) entering the United States (US) Army Infantry Basic Officer Leaders Course (IBOLC) with the intention to complete the US Ranger Course. Volunteer participants consumed eight dietary supplements daily of krill oil containing 2.3 g omega-3 or control (macadamia nut oil) over an approximate 20-week period. Cognitive functioning, resilience, and mood were assessed during a well-rested period at approximately 14 weeks and after a battlefield simulation at 16 weeks. Blood spot samples were collected to monitor compliance and dietary intake was assessed. All hypotheses were tested using both 'Intention to Treat' (ITT) and 'As Per Protocol' (APP) approaches. Of the 555 randomized individuals, 245 (44.1%) completed the study. No statistically significant group-by-time interactions indicating treatment effect were found on any outcomes. Poor compliance was indicated by lower than expected omega-3 elevations in the treatment group, and may have contributed to a failure to detect a response.
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A Critical Review of the Study of Neuroprotective Diets to Reduce Cognitive Decline.
Duplantier, SC, Gardner, CD
Nutrients. 2021;(7)
Abstract
Alzheimer's disease (AD) and other dementias are now the seventh leading cause of death in the world and are projected to affect 115.4 million people by 2050. Delaying the onset of AD by just five years is estimated to reduce the cost and prevalence of the disease by half. There is no cure for AD nor any drug therapies to halt its progression once the disease begins. Lifestyle choices including diet are being seen as a viable complementary therapy to reduce cognitive decline, the hallmark of AD. Mediterranean, DASH (Dietary Approaches to Stop Hypertension), and MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diets have biological mechanisms supporting their potential neuroprotective benefits, but the findings of study outcomes about these benefits have been inconsistent. This paper analyzed five Randomized Clinical Trials (RCTs) (from 2000 to 2021) and 27 observational studies (from 2010 to 2021) focused on the link between cognitive health and the Mediterranean/DASH/MIND diets to identify gaps and challenges that could lead to inconsistent results. These include a lack of accuracy in assessing food intake, multiple dietary pattern scoring systems, a shifting metric among studies focused on the Mediterranean diet, a lack of standards in the tools used to assess cognitive decline, and studies that were underpowered or had follow-up periods too short to detect cognitive change. Insights from these gaps and challenges are summarized in recommendations for future RCTs, including both pragmatic and explanatory RCTs.