Association of Loneliness with Functional Connectivity MRI, Amyloid-ß PET, and Tau PET Neuroimaging Markers of Vulnerability for Alzheimer's Disease.

Background: Loneliness has been declared an "epidemic" associated with negative physical, mental, and cognitive health outcomes such as increased dementia risk. Less is known about the relationship between loneliness and advanced neuroimaging correlates of Alzheimer's disease (AD). Objective: To assess whether loneliness was associated with advanced neuroimaging markers of AD using neuroimaging data from Framingham Heart Study (FHS) participants without dementia. Methods: In this cross-sectional observational analysis, we used functional connectivity MRI (fcMRI), amyloid-ß (Aß) PET, and tau PET imaging data collected between 2016 and 2019 on eligible FHS cohort participants. Loneliness was defined as feeling lonely at least one day in the past week. The primary fcMRI marker was Default Mode Network intra-network connectivity. The primary PET imaging markers were Aß deposition in precuneal and FLR (frontal, lateral parietal and lateral temporal, retrosplenial) regions, and tau deposition in the amygdala, entorhinal, and rhinal regions. Results: Of 381 participants (mean age 58 [SD 10]) who met inclusion criteria for fcMRI analysis, 5% were classified as lonely (17/381). No association was observed between loneliness status and network changes. Of 424 participants (mean age 58 [SD = 10]) meeting inclusion criteria for PET analyses, 5% (21/424) were lonely; no associations were observed between loneliness and either Aß or tau deposition in primary regions of interest. Conclusions: In this cross-sectional study, there were no observable associations between loneliness and select fcMRI, Aß PET, and tau PET neuroimaging markers of AD risk. These findings merit further investigation in prospective studies of community-based cohorts.

Topical Review of Hobbies and Cognitive Health.

BACKGROUND: Establishing preventive measures to improve cognitive health of the growing older adult population is a public health priority. Though, the links between low-cost non-pharmacologist interventions that target activities like hobbies and cognitive health remain unclear. OBJECTIVE: We conducted a topical review of extant literature to characterize prior findings in context and identify potential research opportunities. METHODS: Search criteria was conducted with search terms "Hobbies and Dementia", "Hobbies and Cognitive Health," "Leisure Activities and Dementia," and "Leisure Activities and Cognitive Health". From the initial 383 articles, 25 articles were selected for review by using broad inclusion and exclusion criteria. RESULTS: Of the 25 articles included in this review, 19 were longitudinal cohort, 1 was a retrospective cohort, 2 were case-control, and 3 were cross-sectional. These studies classified hobbies as leisure activities that were cognitive/intellectual, cultural, religious, social, gardening, traveling, or physical. These studies were conducted in the United States (9), United Kingdom (3), Sweden (3), France (5), Finland (1), Korea (1), Japan (2), and China (1). The associations of different types of hobbies with dementia from these studies were not consistent. Inconsistencies could be due to limitations of study design, lack of standardized methods, sample diversity, and differences in factors like social/cultural environment across the study populations. CONCLUSION: This review examined existing evidence for the association between engagement in different types of hobbies and dementia and identified key knowledge gaps and promising approaches for future research.

Markers of infection and inflammation are associated with post-thrombectomy mortality in acute stroke.

OBJECTIVE: We explored the relationship between markers of infection and inflammation and mortality in patients with acute ischemic stroke who underwent thrombectomy. METHODS: We performed retrospective chart review of stroke patients who underwent thrombectomy at two tertiary academic centers between December 2018 and November 2020. Associations between discharge mortality, WBC count, neutrophil percentage, fever, culture data, and antibiotic treatment were analyzed using the Wilcoxon rank sum test, Student's t-test, and Fisher's exact test. Independent predictors of mortality were identified with multivariable analysis. Analyses were repeated excluding COVID-positive patients. RESULTS: Of 248 patients who underwent thrombectomy, 41 (17 %) died prior to discharge. Mortality was associated with admission WBC count (11 [8-14] vs. 9 [7-12], p = 0.0093), admission neutrophil percentage (78 % ± 11 vs. 71 % ± 14, p = 0.0003), peak WBC count (17 [13-22] vs. 12 [9-15], p < 0.0001), fever (71 % vs. 27 %, p < 0.0001), positive culture (44 % vs. 15 %, p < 0.0001), and days treated with antibiotics (3 [1-7] vs. 1 [0-4], p < 0.0001). After controlling for age, admission NIHSS and post-thrombectomy ASPECTS score, mortality was associated with admission WBC count (OR 13, CI 1.32-142, p = 0.027), neutrophil percentage (OR 1.03, CI 1.0-1.07, p = 0.045), peak WBC count (OR 301, CI 24-5008, p < 0.0001), fever (OR 24.2, CI 1.77-332, p < 0.0001), and positive cultures (OR 4.24, CI 1.87-9.62, p = 0.0006). After excluding COVID-positive patients (n = 14), peak WBC count, fever and positive culture remained independent predictors of mortality. CONCLUSION: Markers of infection and inflammation are associated with discharge mortality after thrombectomy. Further study is warranted to investigate the causal relationship of these markers with clinical outcome.

Non-Pharmacologic Interventions for Hispanic Caregivers of Persons with Dementia: Systematic Review and Meta-Analysis.

BACKGROUND: As the Hispanic/Latino (HL) population grows, so too does the need for HL family caregivers for persons with dementia. HL caregivers tend to have less education, lower health literacy, and lower income, each uniquely compounding burden. Research is needed to appropriately tailor interventions for this population. OBJECTIVE: A systematic review and meta-analysis was conducted to 1) provide an updated review of non-pharmacologic intervention studies for HL dementia caregivers, 2) characterize promising interventions, and 3) highlight opportunities for future research. METHODS: Databases were searched for articles evaluating non-pharmacologic interventions for HL dementia caregivers. Studies were excluded if target populations did not include HLs or if no intervention was delivered. Data were extracted and random effects meta-analysis was performed on two primary outcomes: caregiver depression and burden. Effect sizes were calculated as pre- and post-intervention standardized mean differences (SMD), and further depression subgroup meta-analysis was performed. Other secondary outcome measures (e.g., perceived social support, caregiver knowledge, anxiety) were evaluated qualitatively. RESULTS: Twenty-three studies were identified. Most included multiple components pertaining to psychosocial support, caregiver education, and community resource facilitation. Many studies were successful in improving caregiver outcomes, though intervention design varied. Meta-analysis revealed minimal to moderate heterogeneity and small effect size in improving depressive symptoms (SMD = -0.31, 95% CI -0.46 to -0.16; I2 = 50.16%) and burden (SMD = -0.28, 95% CI -0.37 to -0.18; I2 = 11.06%). CONCLUSION: Although intervention components varied, many reported outcome improvements. Future studies may benefit from targeting physical health, addressing sociocultural and economic contexts of caregivers, and leveraging technology.

Pre-admission antithrombotic use is associated with 3-month mRS score after thrombectomy for acute ischemic stroke.

In patients who undergo thrombectomy for acute ischemic stroke, the relationship between pre-admission antithrombotic (anticoagulation or antiplatelet) use and both radiographic and functional outcome is not well understood. We sought to explore the relationship between pre-admission antithrombotic use in patients who underwent thrombectomy for acute ischemic stroke at two medical centers in New York City between December 2018 and November 2020. Analyses were performed using analysis of variance and Pearson's chi-squared tests. Of 234 patients in the analysis cohort, 65 (28%) were on anticoagulation, 64 (27%) were on antiplatelet, and 105 (45%) with no antithrombotic use pre-admission. 3-month Modified Rankin Scale (mRS) score of 3-6 was associated with pre-admission antithrombotic use (71% anticoagulation vs. 77% antiplatelet vs. 56% no antithrombotic, p = 0.04). There was no relationship between pre-admission antithrombotic use and Thrombolysis in Cerebral Iinfarction (TICI) score, post-procedure Alberta Stroke Program Early CT Score (ASPECTS) score, rate of hemorrhagic conversion, length of hospital admission, discharge NIH Stroke Scale (NIHSS), discharge mRS score, or mortality. When initial NIHSS score, post-procedure ASPECTS score, and age at admission were included in multivariate analysis, pre-admission antithrombotic use was still significantly associated with a 3-month mRS score of 3-6 (OR 2.36, 95% CI 1.03-5.54, p = 0.04). In this cohort of patients with acute ischemic stroke who underwent thrombectomy, pre-admission antithrombotic use was associated with 3-month mRS score, but no other measures of radiographic or functional outcome. Further research is needed on the relationship between use of specific anticoagulation or antiplatelet agents and outcome after acute ischemic stroke, but moreover, improve stroke prevention.

Bayesian screening for feature selection.

Biomedical applications such as genome-wide association studies screen large databases with high-dimensional features to identify rare, weakly expressed, and important continuous-valued features for subsequent detailed analysis. We describe an exact, rapid Bayesian screening approach with attractive diagnostic properties using a Gaussian random mixture model focusing on the missed discovery rate (the probability of failing to identify potentially informative features) rather than the false discovery rate ordinarily used with multiple hypothesis testing. The method provides the likelihood that a feature merits further investigation, as well as distributions of the effect magnitudes and the proportion of features with the same expected responses under alternative conditions. Important features include the dependence of the critical values on clinical and regulatory priorities and direct assessment of the diagnostic properties.

Tachycardia is associated with mortality and functional outcome after thrombectomy for acute ischemic stroke.

BACKGROUND: The relationship between cardiac function and mortality after thrombectomy for acute ischemic stroke is not well elucidated. METHODS: We analyzed the relationship between cardiac function and mortality prior to discharge in a cohort of patients who underwent thrombectomy for acute ischemic stroke at two large medical centers in New York City between December 2018 and November 2020. All analyses were performed using Welch's two sample t-test and logistic regression accounting for age, initial NIHSS and post-procedure ASPECTS score, where OR is for each unit increase in the respective variables. RESULTS: Of 248 patients, 41 (16.5%) died prior to discharge. Mortality was significantly associated with higher initial heart rate (HR; 89 ± 19 bpm vs 80 ± 18 bpm, p = 0.004) and higher maximum HR over entire admission (137 ± 26 bpm vs 114 ± 25 bpm, p < 0.001). Mortality was also associated with presence of NSTEMI/STEMI (63% vs 29%, p < 0.001). When age, initial NIHSS score, and post-procedure ASPECTS score were included in multivariate analysis, there was still a significant relationship between mortality and initial HR (OR 1.03, 95% CI 1.01- 1.05, p = 0.02), highest HR over the entire admission (OR 1.03, 95% CI 1.02-1.05, p < 0.001), and presence of NSTEMI/STEMI (OR 3.76, 95% CI 1.66-8.87, p = 0.002). CONCLUSIONS: Tachycardia is associated with mortality in patients who undergo thrombectomy. Further investigation is needed to determine whether this risk is modifiable.

Wortmannin Attenuates Seizure-Induced Hyperactive PI3K/Akt/mTOR Signaling, Impaired Memory, and Spine Dysmorphology in Rats.

Numerous studies have shown epilepsy-associated cognitive deficits, but less is known about the effects of one single generalized seizure. Recent studies demonstrate that a single, self-limited seizure can result in memory deficits and induces hyperactive phosphoinositide 3-kinase/Akt (protein kinase B)/mechanistic target of rapamycin (PI3K/Akt/mTOR) signaling. However, the effect of a single seizure on subcellular structures such as dendritic spines and the role of aberrant PI3K/Akt/mTOR signaling in these seizure-induced changes are unclear. Using the pentylenetetrazole (PTZ) model, we induced a single generalized seizure in rats and: (1) further characterized short- and long-term hippocampal and amygdala-dependent memory deficits, (2) evaluated whether there are changes in dendritic spines, and (3) determined whether inhibiting hyperactive PI3K/Akt/mTOR signaling rescued these alterations. Using the PI3K inhibitor wortmannin (Wort), we partially rescued short- and long-term memory deficits and altered spine morphology. These studies provide evidence that pathological PI3K/Akt/mTOR signaling plays a role in seizure-induced memory deficits as well as aberrant spine morphology.