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Background: Medial temporal lobe atrophy has been linked to decline in neuropsychological measures of explicit memory function. While the hippocampus has long been identified as a critical structure in learning and memory processes, less is known about contributions of the amygdala to these functions. We sought to investigate the relationship between amygdala volume and memory functioning in a clinical sample of older adults. Methods: A serial clinical sample of older adults that underwent neuropsychological assessment at an outpatient neurology clinic was selected for retrospective chart review. Patients were included in the study if they completed a comprehensive neuropsychological assessment within six months of a volumetric MRI scan. Each subject underwent scans conducted on a GE 3.0 Tesla scanner, and volumetric analyses were performed using imaging software which quantifies regional brain volumes. We used bilateral hippocampal and amygdala volumes in our analyses. Associations between these volumes and memory scores, derived from immediate and delayed recall conditions of a verbal story learning task and a nonverbal design reconstruction task [1], were examined using mixed‐effects general linear models, controlling for total intracranial volume, age, sex and education. Partial correlation coefficients, controlling for these covariates, were calculated to estimate the strength of the association between volumes and memory scores. Results: A total of 68 (38F, 29M) participants were included in the analyses, with a mean (SD) age of 80.1 (6.0) and educational level of 15.9 (2.5) years. Controlling for age, sex, education, and total intracranial volume, greater amygdala volumes were associated with better verbal and nonverbal memory performance (p<.001), comparable to hippocampal volume. The interaction term of hemisphere and memory was not significant for any of the models, indicating no lateralized effects. Partial correlation coefficients ranged from 0.45 to 0.31. Conclusion: These findings contribute to a growing body of knowledge highlighting the amygdala as a target for further research in memory functioning through the adult lifespan, supporting a holistic understanding of limbic system operations in which multiple subcortical structures contribute synergistically to memory processes and decline in older adults. References [1] Wechsler, D. (2009). Wechsler Memory Scale fourth edition. San Antonio, TX: Pearson. [ABSTRACT FROM AUTHOR]

Background: Personalized multi‐modal interventions for Alzheimer dementia hold promise to slow progression of symptoms yet related quantitative neuroimaging biomarkers have not been investigated[1,2]. Method: We selected 16 participants (mean age 68.6±5.9 [range 57‐77] years, 50% female) from the Pacific Brain Health Center at Providence St. John's Health Center, with biomarker evidence of Alzheimer dementia amyloidosis. All participants received data‐supported clinical recommendations (DSCR), [3–7] which included a modified SHIELD program[8] recommending a low carbohydrate diet. DSCRs were personalized based on clinical evaluations and laboratory values and closely overseen by a dementia specialist (DM, CW). T1‐weighted MR images were acquired at baseline and with a 1‐year average follow up. Total gray and white matter, hippocampal, lateral ventricle, temporal, parietal, occipital and frontal lobe volumes were quantified using Neuroreader[9]. Global cognition was tested using the Montreal Cognitive Assessment (MoCA). Paired t‐tests were done for these metrics. Result: Changes in hippocampal volumes (t=+1.6, p=0.11), temporal (t=+0.03, p=0.97) and frontal lobes (t=‐0.63, p=0.53) were not significant. There was a marginally significant decline in the parietal lobes (t=+2.1, p=.048) and statistically significant increased lateral ventricles (t=‐4.9, p<0.01). White matter volume declined significantly (t=‐2.8, p=0.01) while gray matter did not change significantly (t=+1.2, p=0.21). Table 1 shows annualized percent changes for these regions. These changes were attenuated compared to literature values for the following regions: gray matter at ‐2%/year [10], hippocampus at ‐3.5%/year [11], temporal lobes at ‐3.23%/year, parietal lobes at ‐3.62%/year and frontal lobes at ‐2.88%/year [12]. Total gray matter and frontal lobe volumes showed increased average annualized changes at +1.97%/year and +0.87%/year respectively. Over the same time period as the brain‐volume trajectory measurements, there was an average decline in MoCA (‐1.5 from 22.06±4.1 to 20.56±6.1, p=0.06) that trended towards but was not statistically significant. Conclusion: Regional volume loss, while present, was moderated compared to literature derived rates. Increased ventricular volumes appear driven by white matter volume loss. These preliminary data suggest that efforts to track and report on clinical outcomes in settings providing close medical management and multimodal lifestyle recommendations may be a worthwhile step towards validating research findings. [ABSTRACT FROM AUTHOR]

Background: Maintaining healthy lifestyle behaviors and optimizing health may slow cognitive decline through risk reduction in older adults with cognitive impairments. Curriculum‐based health coaching, weekly psychosocial support, and use of biomarkers to guide health optimization may aid in establishing effective behavior change centered around multiple reversible dementia risk factors. Method: We piloted combined use of a six‐month online Cognitive Health Program (www.amosinstitute.com) with a telehealth lifestyle support group in six patients with subjective cognitive complaints receiving ongoing outpatient memory care. These patients were given lab‐guided personalized health recommendations for dementia risk reduction throughout the pilot intervention during monthly individual appointments with the study physician overseeing the group. A registered dietician was invited to lead the weekly telehealth lifestyle support group, which was delivered in partnership with the Center's memory clinicians and health coaches. Highlights of the online Cognitive Health Program were reviewed by the dietician each week followed by group discussion on topics including diet, exercise, sleep, stress, and cognitive training. Cognition was assessed at baseline and post‐intervention using a computerized battery (www.cambridgebrainsciences.com). The significance of cognitive changes was estimated with nonparametric tests and effect sizes (Cohen's d). The participants were also queried qualitatively on adherence and satisfaction. Result: Compared to baseline, the participants improved significantly in the global cognition score (p<.02, d = 1.6), and had significant improvements in spatial planning (p<.01, d = 2.3) and visuospatial processing (p<.05, d = 1.1). There was a borderline improvement in verbal reasoning (p<.06, d = 1.0). Subjective reports indicated that participants were able to successfully adhere to multiple lifestyle habits in the areas of sleep, nutrition, and exercise. Participants reported high levels of satisfaction with the virtual group format, the online curriculum, and access to the additional online resources. Conclusion: A virtually administered, six‐month, weekly health coaching group that addresses multiple lifestyle factors associated with brain health, supplemented by self‐paced online health education and lab‐based health optimization by a physician, is feasible and potentially efficacious for improving cognition in participants with subjective cognitive impairment. This format may facilitate behavior change to slow cognitive decline. Future studies will include neuroimaging, formal neuropsychological testing, controls, and larger sample sizes. [ABSTRACT FROM AUTHOR]

Background: Handgrip strength is important for performing activities of daily living[1]. In older adults, weaker handgrip strength and asymmetry are associated with poorer cognition. o better understand mechanisms, we sought to quantify the relationship between handgrip strength and regional volumes quantified on brain MR imaging. Method: We selected 32 participants (mean age=70.8±7.3 [range 57‐89] years, 53.1% female, 90.6% right‐handed, mean body mass index BMI=23.9±4.1) from the Pacific Brain Health Center at Providence St. John's Health Center, with Alzheimer dementia biomarker evidence of amyloidosis[2]. Mean Montreal Cognitive Assessment score for all participants was 21.3±3.8 points. Handgrip strength on dominant and non‐dominant hands was measured using the NIH Motor Toolbox[3] as part of a cognitive fitness assessment using a hydraulic hand dynamometer. The resulting scores included handgrip strength and percentile comparisons to normative data. Asymmetry scores were calculated. Regional brain volumes, including lobar structures and the hippocampus, were measured from T1‐weighted MR images using Neuroreader[4]. Partial correlations (rp), adjusting for age, sex, BMI and total intracranial volume modeled handgrip strength, asymmetry, and brain volumes with a significance threshold of p<0.05. Result: In the dominant hand, higher handgrip strength scores and percentiles were associated with larger volumes in the left frontal lobe (rp=+0.51, p=0.007; rp =+0.47, p=0.01) and right parietal lobe (rp=+0.40, p=0.03; rp=+0.39, p=0.04). In the non‐dominant hand, higher handgrip strength score and percentiles were associated with smaller total cerebral spinal fluid (CSF) volume (rp =‐0.55, p=0.004; rp =‐0.52, p =0.006) and larger volumes within the left hippocampus (rp=+0.45, p=0.01; rp=+.43, p=0.02), right hippocampus (rp=+0.47, p=0.01; rp=+0.43, p=0.02), and right parietal lobe (rp=+0.39, p=0.04; rp=+0.44, p=0.02). Handgrip strength asymmetry was inversely related to right hippocampal volume (rp=‐0.58, p=0.002) and positively correlated to CSF volume (rp=+0.39, p=0.04). Conclusion: Greater handgrip strength was related to larger regional brain volumes. A higher number of brain regions were related to the non‐dominant hand. Asymmetry was associated with lower right hippocampal volume and higher CSF volume. Interventions focused on improving handgrip strength may seek to include quantified brain volumes on MR imaging as endpoints. [ABSTRACT FROM AUTHOR]