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Cover page of Depression is associated with hippocampal volume loss in adults with HIV.

Depression is associated with hippocampal volume loss in adults with HIV.

(2021)

Depressive symptoms are more prevalent in persons with HIV (PWH) than HIV-uninfected individuals. In HIV-uninfected individuals, depression has been associated with atrophy in the hippocampus and other brain regions. In the present study, we investigated the impact of depression on brain structure in PWH. One hundred PWH participated in a cross-sectional study (56.6 ± 6.4 yrs, range 41-70 yrs, 24 females, 63 African Americans). The Beck's Depression Inventory-II (BDI-II) was used to assess depressive symptoms. Structural MRI images were collected. Both the voxel-based morphometry (VBM) technique and a region of interest (ROI) based approach were used to examine the relationship between hippocampal gray matter volume (GMv) and depressive symptoms. The impact of HIV CD4 nadir and antidepressants was also investigated. Both VBM and ROI approaches revealed that higher BDI-II scores (implicating more severe depressive symptoms) were associated with loss of hippocampal GMv, especially in the right hippocampus and the right entorhinal cortex. Low CD4 nadir predicted additional hippocampal volume loss independent of depressive symptoms. Taking antidepressants did not have a detectable effect on hippocampal volume. In summary, having more depressive symptoms is associated with smaller hippocampal volume in PWH, and a history of severe immunosuppression (i.e., low CD4 nadir) correlates with additional hippocampal volume reduction. However, the impact of depression on hippocampal volume may be independent of HIV-disease severity such as low CD4 nadir.

Cover page of Relationship between level of response to alcohol and acute tolerance.

Relationship between level of response to alcohol and acute tolerance.

(2021)

Background

A low level of response (low LR) to alcohol correlates with the later development of alcohol-related problems. Although some of the underpinnings of LR are understood, little is known about the potential relationship between LR and acute tolerance. The current analyses tested the hypothesis that a low LR will be explained in part by more intense acute tolerance to alcohol during a drinking session.

Methods

Data were generated through a reanalysis of data from 120 individuals who were 18- to 25-year-old, sex-matched pairs of low and high LR drinkers who at baseline did not yet meet criteria for an alcohol use disorder. Each subject participated in an oral alcohol challenge after consuming about 0.7ml ethanol per kg and acute tolerance was measured as the differences in alcohol's effects at similar breath alcohol levels (BrACs) during the rising and falling breath alcohol (BrAC) curve. Measures included aspects of the Subjective High Assessment Scale (SHAS) and body sway.

Results

Contrary to our hypothesis, but similar to results with other alcohol measures, acute tolerance was actually significantly attenuated in low LR compared with high LR individuals on most SHAS scores. Neither LR group demonstrated acute tolerance to alcohol for sleepiness or body sway. Men and women did not differ on any of these measures.

Conclusion

These data do not support a role of acute tolerance in the low LR to alcohol as measured by subjective feelings of intoxication or body sway in these subjects, findings that were similar across males and females. In addition, consistent with the literature, the analyses demonstrated differences in acute tolerance across measures such that this phenomenon was observed for most measures of subjective effects but not for body sway. Among the subjective effects, acute tolerance was observed for alcohol's intoxicating effect but not for feeling sleepy.

Cover page of Object attachment as we grow older.

Object attachment as we grow older.

(2021)

Extreme object attachment in adults can form as a way to compensate for a lack of interpersonal attachment or as a symptom of hoarding disorder; however, normative levels of object attachment also exist across the lifespan. Although the importance of secure interpersonal attachment as a protective factor for older adults has been well established, research into object attachment in older adults is still a nascent field. As individuals age, they inevitably experience a series of cognitive, emotional, and physical changes that may influence their attachment to objects. Life events may impact the way that we view our possessions, particularly over time. Given individual differences, multiple pathways may affect normative object attachment as we age.

Cover page of Health Impacts of the Stay-at-Home Order on Community-Dwelling Older Adults and How Technologies May Help: Focus Group Study (Preprint)

Health Impacts of the Stay-at-Home Order on Community-Dwelling Older Adults and How Technologies May Help: Focus Group Study (Preprint)

(2021)

BACKGROUND

As of March 2021, in the USA, the COVID-19 pandemic has resulted in over 500,000 deaths, with a majority being people over 65 years of age. Since the start of the pandemic in March 2020, preventive measures, including lockdowns, social isolation, quarantine, and social distancing, have been implemented to reduce viral spread. These measures, while effective for risk prevention, may contribute to increased social isolation and loneliness among older adults and negatively impact their mental and physical health.

OBJECTIVE

This study aimed to assess the impact of the COVID-19 pandemic and the resulting “Stay-at-Home” order on the mental and physical health of older adults and to explore ways to safely increase social connectedness among them.

METHODS

This qualitative study involved older adults living in a Continued Care Senior Housing Community (CCSHC) in southern California, USA. Four 90-minute focus groups were convened using the Zoom Video Communications platform during May 2020, involving 21 CCSHC residents. Participants were asked to describe how they were managing during the “stay-at-home” mandate that was implemented in March 2020, including its impact on their physical and mental health. Transcripts of each focus group were analyzed using qualitative methods.

RESULTS

Four themes emerged from the qualitative data: (1) impact of the quarantine on health and well-being, (2) communication innovation and technology use, (3) effective ways of coping with the quarantine, and (4) improving access to technology and training. Participants reported a threat to their mental and physical health directly tied to the quarantine and exacerbated by social isolation and decreased physical activity. Technology was identified as a lifeline for many who are socially isolated from their friends and family.

CONCLUSIONS

Our study findings suggest that technology access, connectivity, and literacy are potential game-changers to supporting the mental and physical health of older adults and must be prioritized for future research.

Cover page of Associations Between Heart Rate Variability Measured With a Wrist-Worn Sensor and Older Adults’ Physical Function: Observational Study (Preprint)

Associations Between Heart Rate Variability Measured With a Wrist-Worn Sensor and Older Adults’ Physical Function: Observational Study (Preprint)

(2021)

BACKGROUND

Heart rate variability (HRV), or variation in beat-to-beat intervals of the heart, is a quantitative measure of autonomic regulation of the cardiovascular system. Low HRV derived from electrocardiogram (ECG) recordings is reported to be related to physical frailty in older adults. Recent advances in wearable technology offer opportunities to more easily integrate monitoring of HRV into regular clinical geriatric health assessments. However, signals obtained from ECG versus wearable photoplethysmography (PPG) devices are different, and a critical first step preceding their widespread use is to determine whether HRV metrics derived from PPG devices also relate to older adults’ physical function.

OBJECTIVE

This study aimed to investigate associations between HRV measured with a wrist-worn PPG device, the Empatica E4 sensor, and validated clinical measures of both objective and self-reported physical function in a cohort of older adults living independently within a continuing care senior housing community. Our primary hypothesis was that lower HRV would be associated with lower physical function. In addition, we expected that HRV would explain a significant proportion of variance in measures of physical health status.

METHODS

We evaluated 77 participants from an ongoing study of older adults aged between 65 and 95 years. The assessments encompassed a thorough examination of domains typically included in a geriatric health evaluation. We collected HRV data with the Empatica E4 device and examined bivariate correlations between HRV quantified with the triangular index (HRV TI) and 3 widely used and validated measures of physical functioning—the Short Physical Performance Battery (SPPB), Timed Up and Go (TUG), and Medical Outcomes Study Short Form 36 (SF-36) physical composite scores. We further investigated the additional predictive power of HRV TI on physical health status, as characterized by SF-36 physical composite scores and Cumulative Illness Rating Scale for Geriatrics (CIRS-G) scores, using generalized estimating equation regression analyses with backward elimination.

RESULTS

We observed significant associations of HRV TI with SPPB (n=52; Spearman ρ=0.41; P=.003), TUG (n=51; ρ=−0.40; P=.004), SF-36 physical composite scores (n=49; ρ=0.37; P=.009), and CIRS-G scores (n=52, ρ=−0.43; P=.001). In addition, the HRV TI explained a significant proportion of variance in SF-36 physical composite scores (R2=0.28 vs 0.11 without HRV) and CIRS-G scores (R2=0.33 vs 0.17 without HRV).

CONCLUSIONS

The HRV TI measured with a relatively novel wrist-worn PPG device was related to both objective (SPPB and TUG) and self-reported (SF-36 physical composite) measures of physical function. In addition, the HRV TI explained additional variance in self-reported physical function and cumulative illness severity beyond traditionally measured aspects of physical health. Future steps include longitudinal tracking of changes in both HRV and physical function, which will add important insights regarding the predictive value of HRV as a biomarker of physical health in older adults.

Cover page of "PrEP"ing for a PrEP demonstration project: understanding PrEP knowledge and attitudes among cisgender women.

"PrEP"ing for a PrEP demonstration project: understanding PrEP knowledge and attitudes among cisgender women.

(2021)

Background

Prior to implementing a pre-exposure prophylaxis (PrEP) demonstration study, we sought to explore cisgender women's experiences with HIV prevention, PrEP knowledge and attitudes, and anticipated barriers and facilitators for PrEP uptake and adherence in Southern California.

Methods

Three focus groups were held with cisgender women of mixed HIV serostatus in San Diego and Los Angeles between November 2015 and January 2016. Women were recruited through local testing sites, community-based organizations, and social media. Focus groups were audio-recorded and transcripts were analyzed using thematic analysis.

Results

Twenty-two women participated in focus groups, with median age 44 (IQR 30-53) and 6 identifying as non-Hispanic Black, 7 non-Hispanic White, 8 Latina and 1 mixed race. Despite limited prior PrEP knowledge and no PrEP experience, participants expressed interest in taking PrEP. Anticipated benefits were freedom from worry about HIV and control over sexual health; however, these were tempered by concerns including the possibility of increased HIV risk behaviors and potential side effects. Cisgender women reported potential barriers to PrEP uptake and adherence barriers, like competing priorities and poor PrEP access. Conversely, PrEP facilitators included utilizing practical tools such as phone apps and pill boxes as well as receiving encouragement from loved ones and support from other cisgender women on PrEP, women living with HIV and their medical providers.

Conclusions

Although PrEP awareness was low, participants recognized the importance of PrEP and ways to facilitate adherence. Exploring perspectives of cisgender women is integral to developing effective interventions to support PrEP uptake and adherence for women at elevated risk for HIV.

Cover page of Implementation determinants and mechanisms for the prevention and treatment of adolescent HIV in sub-Saharan Africa: concept mapping of the NIH Fogarty International Center Adolescent HIV Implementation Science Alliance (AHISA) initiative.

Implementation determinants and mechanisms for the prevention and treatment of adolescent HIV in sub-Saharan Africa: concept mapping of the NIH Fogarty International Center Adolescent HIV Implementation Science Alliance (AHISA) initiative.

(2021)

Introduction

Adolescent HIV prevention and treatment is a high priority for youth healthcare in sub-Saharan Africa.

Methods

This study employed concept mapping to identify factors that impact the implementation of HIV prevention and intervention programs for adolescents in sub-Saharan Africa. Key stakeholders including researchers, policymakers, and non-governmental organization (NGO) personnel constituting membership of the NIH-sponsored Adolescent HIV Prevention and Treatment Implementation Science Alliance responded to the question: "In your experience, what factors have facilitated or hindered implementation of evidence-based HIV prevention or treatment for adolescents in sub-Saharan Africa?" Participants generated statements in response to the focus question, sorted them into thematically relevant groups, and rated each statement on its importance and changeability.

Results

Through data analyses and participant feedback, 15 distinct themes were derived. "Workforce/Workflow" and "HIV Stigma and Adolescent Development" were rated highest for importance, and "Threshold Conditions for Treatment" and "Structure of Implementation Efforts" were rated most changeable.

Conclusions

Understanding implementation science determinants and mechanisms can facilitate the uptake of successful implementation and sustainment strategies for the prevention and treatment of HIV in a given context. We placed determinants and mechanisms within the Exploration, Preparation, Implementation, Sustainment (EPIS) framework to provide greater contextual integration with broader theories in implementation science. Implementers across multiple disciplines can use these findings to improve the scale-up of evidence-based practices for adolescent HIV prevention and treatment in sub-Saharan Africa. Implementation approaches that consider the determinants and mechanisms identified in this study and integrated in implementation frameworks will likely have utility for other health conditions and contexts.

Cover page of Developing functional network connectivity of the dorsal anterior cingulate cortex mediates externalizing psychopathology in adolescents with child neglect.

Developing functional network connectivity of the dorsal anterior cingulate cortex mediates externalizing psychopathology in adolescents with child neglect.

(2021)

Childhood adversity has been associated with elevated risk for psychopathology. We investigated whether development of functional brain networks important for executive function (EF) could serve as potential mediators of this association. We analyzed data of 475 adolescents, a subsample of the multisite longitudinal NCANDA (National Consortium on Alcohol and Neurodevelopment in Adolescence) cohort with completed measures of childhood trauma, resting-state functional brain connectivity data, and symptoms of internalizing and externalizing psychopathology at baseline and follow-up years 1-4. Using parallel process latent growth models, we found that childhood adversity was associated with increased risk for externalizing/internalizing behaviors. We specifically investigated whether functional connectivity of the dorsal anterior cingulate cortex (dACC) to brain regions within the cingulo-opercular (CO) network, a well-known EF network that underlies control of attention and self-regulation, mediates the association between adversity and symptoms of psychopathology. We found that childhood adversity, specifically child neglect was negatively associated with functional connectivity of the dACC within the CO network, and that this connectivity mediated the association between neglect and externalizing behaviors. Our study advances a mechanistic understanding of how childhood adversity may impact the development of psychopathology, highlighting the relevance of dACC functional networks particularly for externalizing psychopathology.

Cover page of Wisdom and fluid intelligence are dissociable in healthy older adults.

Wisdom and fluid intelligence are dissociable in healthy older adults.

(2021)

Objectives

The relationship between wisdom and fluid intelligence (Gf) is poorly understood, particularly in older adults. We empirically tested the magnitude of the correlation between wisdom and Gf to help determine the extent of overlap between these two constructs.

Design

Cross-sectional study with preregistered hypotheses and well-powered analytic plan (https://osf.io/h3pjx).

Setting

Memory and Aging Center at the University of California San Francisco, located in the USA.

Participants

141 healthy older adults (mean age = 76 years; 56% female).

Measurements

Wisdom was quantified using a well-validated self-report-based scale (San Diego Wisdom Scale or SD-WISE). Gf was assessed via composite measures of processing speed (Gf-PS) and executive functioning (Gf-EF). The relationships of SD-WISE scores to Gf-PS and Gf-EF were tested in bivariate correlational analyses and multiple regression models adjusted for demographics (age, sex, and education). Exploratory analyses evaluated the relationships between SD-WISE and age, episodic memory performance, and dorsolateral and ventromedial prefrontal cortical volumes on magnetic resonance imaging.

Results

Wisdom showed a small, positive association with Gf-EF (r = 0.181 [95% CI 0.016, 0.336], p = .031), which was reduced to nonsignificance upon controlling for demographics, and no association with Gf-PS (r = 0.019 [95% CI -0.179, 0.216], p = .854). Wisdom demonstrated a small, negative correlation with age (r = -0.197 [95% CI -0.351, -0.033], p = .019), but was not significantly related to episodic memory or prefrontal volumes.

Conclusions

Our findings indicate that most of the variance in wisdom (>95%) is unaccounted for by Gf. The independence of wisdom from cognitive functions that reliably show age-associated declines suggests that it may hold unique potential to bolster decision-making, interpersonal functioning, and other everyday activities in older adults.