Faculty Bibliography

Background Vascular function is compromised in Alzheimer disease (AD) years before amyloid and tau pathology are detected and a substantial body of work shows abnormal platelet activation states in patients with AD. The aim of our study was to investigate whether platelet function in middle age is independently associated with future risk of AD. Methods and Results We examined associations of baseline platelet function with incident dementia risk in the community-based FHS (Framingham Heart Study) longitudinal cohorts. The association between platelet function and risk of dementia was evaluated using the cumulative incidence function and inverse probability weighted Cox proportional cause-specific hazards regression models, with adjustment for demographic and clinical covariates. Platelet aggregation response was measured by light transmission aggregometry. The final study sample included 1847 FHS participants (average age, 53.0 years; 57.5% women). During follow-up (median, 20.5 years), we observed 154 cases of incident dementia, of which 121 were AD cases. Results from weighted models indicated that platelet aggregation response to adenosine diphosphate 1.0 µmol/L was independently and positively associated with dementia risk, and it was preceded in importance only by age and hypertension. Sensitivity analyses showed associations with the same directionality for participants defined as adenosine diphosphate hyper-responders, as well as the platelet response to 0.1 µmol/L epinephrine. Conclusions Our study shows individuals free of antiplatelet therapy with a higher platelet response are at higher risk of dementia in late life during a 20-year follow-up, reinforcing the role of platelet function in AD risk. This suggests that platelet phenotypes may be associated with the rate of dementia and potentially have prognostic value.

OBJECTIVES/OBJECTIVE:Discrimination is a major contributor to health disparities between Black and White older adults. Although the health effects of discrimination are well established, less is known about factors that may intervene in the discrimination-health connection, such as coping strategies. The study aim was to determine whether John Henryism (JH; high-effort coping) moderates the association between racial discrimination and hypertension in nationally representative samples of older African Americans and Caribbean Blacks. METHODS:The analytic sample was drawn from the National Survey of American Life-Reinterview, which was conducted 2001-2003, and included African Americans (N = 546) and Caribbean Blacks (N = 141) aged 55 and older. Study variables included racial discrimination, JH, and hypertension. Logistic regressions, which controlled key sociodemographic differences, were used to test the study aim. RESULTS:Among both Black ethnic groups, discrimination and JH were not associated with hypertension. For African Americans low and moderate in JH, discrimination was unrelated to hypertension; discrimination was positively associated with hypertension for African Americans high in JH. For Caribbean Blacks, discrimination was positively associated with hypertension among respondents low in JH. Among Caribbean Blacks moderate and high in JH, discrimination was not associated with hypertension. DISCUSSION/CONCLUSIONS:The findings indicate that JH, in the face of discrimination, is associated with hypertension of older African Americans but may be an effective coping strategy for older Caribbean Blacks due to cultural and sociodemographic differences between the 2 ethnic groups. Future research should investigate the differing mechanisms by which JH influences health in heterogeneous older Black populations.

Objective/UNASSIGNED:The study objective was to examine predictors of sleep disturbance and strain among caregivers of persons living with dementia (PLWD). Methods/UNASSIGNED:This cross-sectional study utilized a sample of community-dwelling older adults and their family caregivers drawn from the 2017 National Health and Aging Trends Study and National Study of Caregiving. Multivariable logistic regression was used to assess the association between caregiver and PLWD characteristics and a composite measure of caregiving strain. High caregiving strain was defined as a total score of ≥ 5 on the 6 caregiving strain items (e.g., emotional difficulty, no time for self). We used multivariable proportional odds models to examine predictors of caregiver sleep-related outcomes (trouble falling back to sleep and interrupted sleep), after adjusting for other caregiver and PLWD factors. Results/UNASSIGNED:Of the 1,142 family caregivers, 65.2% were female, 15% were Black, and 14% were Hispanic. Average age was 60 years old. Female caregivers were more likely to report high level of strain compared to male caregivers (OR: 2.61, 95% CI = 1.56, 4.39). Compared to non-Hispanic Whites, non-Hispanic Black and Hispanic caregivers had reduced odds of reporting greater trouble falling back asleep [OR = 0.55, CI (0.36, 0.82) and OR = 0.56, CI (0.34, 0.91), respectively]. The odds of reporting greater trouble falling back asleep was significantly greater among caregivers with high blood pressure vs. caregivers without high blood pressure [OR = 1.62, CI (1.12, 2.33)]. Conclusion/UNASSIGNED:In this cross-sectional study, caregivers with greater sleep difficulty (trouble falling back asleep) were more likely to report having high blood pressure. We found no racial/ethnic differences in interrupted sleep among caregivers to PLWD. These results suggest that interventions to improve sleep among caregivers to PLWD may decrease poor cardiovascular outcomes in this group.

OBJECTIVES/OBJECTIVE:We contrasted the relative risks (RR) of short [<7 h] and long [>8 h] sleep experienced by middle-aged (45-64 years) and older (≥65 years) adults, compared with young adults (20-44 years). METHODS:We utilized NHANES data (2005-2016), capturing sociodemographic, socioeconomic, and health-related data among US adults. RESULTS:The Relative Risk (RR) of short sleep between young and middle-aged adults did not differ [RR = 1.02, NS]. However, the RR of short sleep was significantly reduced among older participants [RR = 0.81, p < 0.01]. Middle-aged adults had significantly lower RR of long sleep [RR = 0.80, p < 0.01], whereas older adults had significantly greater RR of long sleep [RR = 1.41, p < 0.01]. Compared with young adults, older adults with or without increased disease burden had significantly lower RR of short sleep [RR = 0.81, p < 0.01 and RR = 0.80, p < 0.01], respectively. However, for middle-aged adults, the RR of short sleep did not differ whether they reported a greater disease burden. Relative to young adults, older adults with or without disease burden had higher RRs of long sleep [RR = 1.39, p < 0.01] and [RR = 1.45, p < 0.01], respectively. For middle-aged adults without disease burden, the RR of long sleep was lower than among young adults [RR = 0.72, p < 0.01]. CONCLUSIONS:Compared with young adults, older adults were not at increased risk for short sleep. Rather, they reported longer sleep time regardless of the presence of disease burden. Future studies should investigate longitudinal effects of aging on objective sleep time, with or without common diseases.

Objective/UNASSIGNED:Compared to European Americans, research indicates that African Americans have higher white matter hyperintensity (WMH) load; however, the clinical and biological bases underlying this higher burden are poorly understood. We hypothesize that obesity may explain differences in WMH between African and European Americans. Methods/UNASSIGNED:, and WMH load, captured by FLAIR images, as sum of deep and periventricular volumes, scored using the Fazekas scale (0-6), WMH≥4 considered high. Results/UNASSIGNED:=5.3, p=0.02). Conclusion/UNASSIGNED:Results denote that age predicted WMH among European Americans, while obesity predicted WMH among African Americans. Matched sample analyses indicate that obesity increases the odds of WMH, though more pronounced in African Americans. These findings suggest that obesity may explain the differential burden of white matter hyperintensity load, signifying public health and clinical importance.

Maintaining influenza vaccination at high coverage has the potential to prevent a proportion of COVID-19 morbidity and mortality. We examined whether flu-vaccination is associated with severe corona virus disease 2019 (COVID-19) disease, as measured by intensive care unit (ICU)-admission, ventilator-use, and mortality. Other outcome measures included hospital length of stay and total ICU days. Our findings showed that flu-vaccination was associated with a significantly reduced likelihood of an ICU admission especially among aged <65 and non-obese patients. Public health promotion of flu-vaccination may help mitigate the overwhelming demand for critical COVID-19 care pending the large-scale availability of COVID-19 vaccines.

Efforts to control the current coronavirus disease 2019 (COVID-19) pandemic have led to national lockdowns around the world. Reactions to the rapidly evolving outbreak were shared on social media platforms. We conducted a mixed-methods analysis of tweets collected from May 10 to May 24, 2020, using MAXQDA software in conjunction with Twitters search API using the keywords: "COVID-19," "coronavirus pandemic," "Covid19," "face masks," and included terms such as "Queens," "Bronx," "New York." A total of 7, 301 COVID-19-related tweets across the globe were analyzed. We used SAS Text Miner V.15.1 for descriptive text mining to uncover the primary topics in unstructured textual data. Content analysis of tweets revealed six themes: surveillance, prevention, treatments, testing and cure, symptoms and transmission, fear, and financial loss. Our study also demonstrates the feasibility of using Twitter to capture real-time data to assess the public's concerns and public health needs during the COVID-19 pandemic.