RESIDENTIAL CONTEXT AND PATHWAYS OF EXPOSURE: EXAMINING RESIDENTIAL SEGREGATION, NEIGHBORHOOD ADVERSITY, AND NEIGHBORHOOD GREENNESS IN RELATION TO HEALTH

Residential context, from the broader structural factors, like racial residential segregation, to the proximate neighborhood environmental factors, is an important social determinant of health. This dissertation comprises two studies investigating how different levels of residential context are associated with both new and existing health outcomes. The first study examined the relationships between three neighborhood characteristics (greenness, disorder, and socioeconomic disadvantage), seven cardiovascular biomarkers, and diurnal cortisol patterns among middle-aged and older adults aged 57-79 years living in Baltimore City. Using multi-level regression models, this study showed that neighborhood disorder and neighborhood socioeconomic disadvantage were associated with higher C-reactive protein, serum amyloid A, and tumor necrosis factor alpha, while neighborhood greenness was associated with lower soluble vascular cell adhesion molecule-1. None of the neighborhood characteristics were associated with interferon gamma, interleukin-6, soluble intercellular adhesion molecule-1, waking cortisol, or diurnal cortisol decline. Further, interactions between neighborhood greenness and neighborhood disorder, and between neighborhood greenness and neighborhood socioeconomic disadvantage, were not statistically significant for cardiovascular biomarkers, waking cortisol, or diurnal cortisol decline. The second study explored county-level associations of two racial residential segregation measures, the Dissimilarity Index and the Index of Concentration at the Extremes (ICE), with six-month coronavirus disease 2019 (COVID-19) cumulative incidence and mortality. Negative binomial regressions showed the Dissimilarity Index was associated with higher cumulative mortality among 2,068 United States counties. A significant interaction term indicated cumulative incidence was higher among counties with higher Dissimilarity Index values and more Black residents. The ICE was associated with higher COVID-19 cumulative incidence and mortality among 2,068 counties with non-missing Dissimilarity Index values and among all 3,141 U.S. counties. The comparison of an ICE model conducted among the 2,068 U.S. counties to a model conducted among all 3,141 U.S. counties suggested no mis-estimation in the COVID-19 associations resulting from geographic selection bias. Together, these studies demonstrate that residential contexts are important to a wide variety of health outcomes. Interventions to reduce health disparities should combine top-down and bottom-up approaches to more effectively address the root causes of unequal residential environments and the direct effects of their physical and social exposures on health

A shared frequency set between the historical mid-latitude aurora records and the global surface temperature

Herein we show that the historical records of mid-latitude auroras from 1700 to 1966 present oscillations with periods of about 9, 10-11, 20-21, 30 and 60 years. The same frequencies are found in proxy and instrumental global surface temperature records since 1650 and 1850, respectively and in several planetary and solar records. Thus, the aurora records reveal a physical link between climate change and astronomical oscillations. Likely, there exists a modulation of the cosmic ray flux reaching the Earth and/or of the electric properties of the ionosphere. The latter, in turn, have the potentiality of modulating the global cloud cover that ultimately drives the climate oscillations through albedo oscillations. In particular, a quasi 60-year large cycle is quite evident since 1650 in all climate and astronomical records herein studied, which also include an historical record of meteorite fall in China from 619 to 1943. These findings support the thesis that climate oscillations have an astronomical origin. We show that a harmonic constituent model based on the major astronomical frequencies revealed in the aurora records is able to forecast with a reasonable accuracy the decadal and multidecadal temperature oscillations from 1950 to 2010 using the temperature data before 1950, and vice versa. The existence of a natural 60-year modulation of the global surface temperature induced by astronomical mechanisms, by alone, would imply that at least 60-70% of the warming observed since 1970 has been naturally induced. Moreover, the climate may stay approximately stable during the next decades because the 60-year cycle has entered in its cooling phase.Comment: 18 pages, 11 figure

“So I am stuck, but it´s OK” : residential reasoning and housing decision-making of low-income older adults with disabilities in Baltimore, Maryland

Housing preferences and housing decision-making in later life are critical aspects of aging in place, which is a public health priority in many Western countries. However, few studies have examined the economic, social, and health factors that guide older adults’ preferences and decisions about where to live, and even less so among older adults with low income or disabilities who may face greater barriers to aging in place. We sought to understand what housing decision-making and residential reasoning means for low-income older adult homeowners in Baltimore, Maryland. Using a grounded theory approach, we interviewed 12 older adults in June 2017 and February 2018. Our findings revealed how the strong desire to age in place turned into the realization that they had to age in place due to limited resources and options. The overarching category “shifting between wanting to age in place and having to age in place” was influenced by family needs, being a homeowner, the neighborhood, and coping at home. In conclusion, for low-income older adults with disabilities, it is important to acknowledge that sometimes aging in place may be equivalent to being stuck in place

Estimation of place-based vulnerability scores for HIV viral non-suppression: an application leveraging data from a cohort of people with histories of using drugs

Abstract The relationships between place (e.g., neighborhood) and HIV are commonly investigated. As measurements of place are multivariate, most studies apply some dimension reduction, resulting in one variable (or a small number of variables), which is then used to characterize place. Typical dimension reduction methods seek to capture the most variance of the raw items, resulting in a type of summary variable we call “disadvantage score”. We propose to add a different type of summary variable, the “vulnerability score,” to the toolbox of the researchers doing place and HIV research. The vulnerability score measures how place, as known through the raw measurements, is predictive of an outcome. It captures variation in place characteristics that matters most for the particular outcome. We demonstrate the estimation and utility of place-based vulnerability scores for HIV viral non-suppression, using data with complicated clustering from a cohort of people with histories of injecting drugs

Preventing falls among older fallers : Study protocol for a two-phase pilot study of the multicomponent LIVE LiFE program

Background: Falls reflect sentinel events in older adults, with significant negative consequences. Although fall risk factors have been identified as intrinsic (e.g., muscle weakness, balance problems) and extrinsic (e.g., home hazards), most prevention programs target only intrinsic factors. We present the rationale and design of a home-based multicomponent fall prevention program - the LIVE LiFE program - for community-living older adults. The program adapts and expands the successful Lifestyle Intervention Functional Exercise (LiFE) program by adding home safety, vision contrast screening, and medication review. The specific aims of the study are to (1) adapt the LiFE program to a US context and expand it into a multicomponent program (LIVE LiFE) addressing intrinsic and extrinsic fall risks, (2) examine feasibility and acceptability, and (3) estimate program impact on multiple outcome measures to prepare for an efficacy trial. Methods: The study involves two phases: an open-label pilot, followed by a two-group, single-blinded randomized pilot trial. Eligible participants are community-living adults 70+ years reporting at least one injurious fall or two non-injurious falls in the previous year. Participants are randomized in a 2:1 ratio to the program group (LIVE LiFE, n = 25) or the control group (written fall risk assessment, n = 12). The open-label pilot participants (n = 3) receive the program without randomization and are assessed based on their experience, resulting in a stronger emphasis on the participant's personal goals being integrated into LIVE LiFE. Fall risk and balance outcomes are assessed by the Timed Up and Go and the 4-Stage Balance Test at 16 weeks. Additional outcomes are incidence of falls and near falls, falls efficacy, fear of falling, number of home hazards, and medications assessed at 16 weeks. Incidence of falls and near falls, program adherence, and satisfaction are assessed again at 32 weeks. Discussion: By expanding and adapting the evidence-based LiFE program, our study will help us understand the feasibility of conducting a multicomponent program and estimate its impact on multiple outcome measures. This will support moving forward with an efficacy trial of the LIVE LiFE program for older adults who are at risk of falling. Trial registration: ClinicalTrials.gov, NCT03351413. Registered on 22 November 2017

Additional file 1 of Estimation of place-based vulnerability scores for HIV viral non-suppression: an application leveraging data from a cohort of people with histories of using drugs

Supplementary Material 1: Appendix

Epidemiology of the Homebound Population in the United States.

ImportanceIncreasing numbers of older, community-dwelling adults have functional impairments that prevent them from leaving their homes. It is uncertain how many people who live in the United States are homebound.ObjectivesTo develop measures of the frequency of leaving and ability to leave the home and to use these measures to estimate the size of the homebound population in the US population.Design, setting, and participantsCross-sectional data from the National Health and Aging Trends Study collected in 2011 in the contiguous United States. Participants were a nationally representative sample of 7603 noninstitutionalized Medicare beneficiaries 65 years and older.Main outcomes and measuresWe defined homebound persons as those who never (completely homebound) or rarely (mostly homebound) left the home in the last month. We defined semihomebound persons as those who only left the home with assistance or had difficulty or needed help leaving the home. We compared demographic, clinical, and health care utilization characteristics across different homebound status categories.ResultsIn 2011, the prevalence of homebound individuals was 5.6% (95% CI, 5.1%-6.2%), including an estimated 395,422 people who were completely homebound and 1,578,984 people who were mostly homebound. Among semihomebound individuals, the prevalence of those who never left home without personal assistance was 3.3% (95% CI, 2.8%-3.8%), and the prevalence of those who required help or had difficulty was 11.7% (95% CI, 10.9%-12.6%). Completely homebound individuals were more likely to be older (83.2 vs 74.3 years, P < .001), female (67.9% vs 53.4%, P < .006), and of nonwhite race (34.1% vs 17.6%, P < .001) and have less education and income than nonhomebound individuals. They also had more chronic conditions (4.9 vs 2.5) and were more likely to have been hospitalized in the last 12 months (52.1% vs 16.2%) (P < .001 for both). Only 11.9% of completely homebound individuals reported receiving primary care services at home.Conclusions and relevanceIn total, 5.6% of the elderly, community-dwelling Medicare population (approximately 2 million people) were completely or mostly homebound in 2011. Our findings can inform improvements in clinical and social services for these individuals