Legacies of Environmental Injustice on Neighborhood Violence, Poverty and Active Living in an African American Community.

Features of the built environment such as parks and open spaces contribute to increased physical activity in populations, while living in neighborhoods with high poverty, racial/ethnic segregation, presence of neighborhood problems, and violence has been associated with less active living. Our present study examined the factors that may facilitate or hinder the long-term success of built environment interventions aimed at promoting physical activity in communities with a legacy of environmental injustice. The data for this study came from a larger assessment of the impact of a new local park in Newark, NJ. Analysis included all adults from the original study population who self-identified as African American/Black (N=95). To provide an in-depth understanding of how neighborhood social and physical features influence physical activity among African Americans living in high poverty neighborhoods, we analyzed data from two focus groups with a total of 14 participants, and six in-depth interviews held in 2009-2010. Survey results indicated high exposure to violence, and associations between neighborhood features and walking. Self-reported neighborhood walkability was associated with increased walking (P=.01), while increased perception of neighborhood safety was associated with less walking (P=.01). Qualitative results indicated that residents perceived the new park as a positive change, but also expressed concern about the presence of violence and lack of social cohesion among neighbors, with younger generations expressing less optimism than the elderly. Positive changes associated with improvements to the built environment may be limited by social conditions such as neighborhood violence. These mixed findings suggest that policies and initiatives aimed at improving the built environment should address poverty, safety, and social cohesion to ensure more active living communities.

Neighborhood social environment and changes in leukocyte telomere length: The Multi-Ethnic Study of Atherosclerosis (MESA).

Given limited research on the impact of neighborhood environments on accelerated biological aging, we examined whether changes in neighborhood socioeconomic and social conditions were associated with change in leukocyte telomere length using 10 years of longitudinal data from the Multi-Ethnic Study of Atherosclerosis (years 2000-2011; N = 1031; mean age = 61, SD = 9.4). Leukocyte telomere length change was corrected for regression to the mean and neighborhood was defined as census tract. Neighborhood socioeconomic indicators (factor-based score of income, education, occupation, and wealth of neighborhood) and neighborhood social environment indicators (aesthetic quality, social cohesion, safety) were obtained from the U.S Census/American Community Survey and via study questionnaire, respectively. Results of linear mixed-effects models showed that independent of individual sociodemographic characteristics, each unit of improvement in neighborhood socioeconomic status was associated with slower telomere length attrition over 10-years (ß = 0.002; 95% Confidence Interval (CI): 0.0001, 0.004); whereas each unit of increase in safety (ß = -0.043; 95% CI: -0.069, -0.016) and overall neighborhood social environment score (ß = -0.005; 95% CI: -0.009, -0.0004) were associated with more pronounced telomere attrition, after additionally adjusting for neighborhood socioeconomic status. This study provides support for considerations of the broader social and socioeconomic contexts in relation to biological aging. Future research should explore potential psychosocial mechanisms underlying these associations using longitudinal study designs with repeated observations.

Machine Learning for Social Services: A Study of Prenatal Case Management in Illinois.

OBJECTIVES: To evaluate the positive predictive value of machine learning algorithms for early assessment of adverse birth risk among pregnant women as a means of improving the allocation of social services. METHODS: We used administrative data for 6457 women collected by the Illinois Department of Human Services from July 2014 to May 2015 to develop a machine learning model for adverse birth prediction and improve upon the existing paper-based risk assessment. We compared different models and determined the strongest predictors of adverse birth outcomes using positive predictive value as the metric for selection. RESULTS: Machine learning algorithms performed similarly, outperforming the current paper-based risk assessment by up to 36%; a refined paper-based assessment outperformed the current assessment by up to 22%. We estimate that these improvements will allow 100 to 170 additional high-risk pregnant women screened for program eligibility each year to receive services that would have otherwise been unobtainable. CONCLUSIONS: Our analysis exhibits the potential for machine learning to move government agencies toward a more data-informed approach to evaluating risk and providing social services. Overall, such efforts will improve the efficiency of allocating resource-intensive interventions.

Systematic and Cell Type-Specific Telomere Length Changes in Subsets of Lymphocytes.

Telomeres, the protective DNA-protein complexes at the ends of linear chromosomes, are important for genome stability. Leukocyte or peripheral blood mononuclear cell (PBMC) telomere length is a potential biomarker for human aging that integrates genetic, environmental, and lifestyle factors and is associated with mortality and risks for major diseases. However, only a limited number of studies have examined longitudinal changes of telomere length and few have reported data on sorted circulating immune cells. We examined the average telomere length (TL) in CD4+, CD8+CD28+, and CD8+CD28- T cells, B cells, and PBMCs, cross-sectionally and longitudinally, in a cohort of premenopausal women. We report that TL changes over 18 months were correlated among these three T cell types within the same participant. Additionally, PBMC TL change was also correlated with those of all three T cell types, and B cells. The rate of shortening for B cells was significantly greater than for the three T cell types. CD8+CD28- cells, despite having the shortest TL, showed significantly more rapid attrition when compared to CD8+CD28+ T cells. These results suggest systematically coordinated, yet cell type-specific responses to factors and pathways contribute to telomere length regulation.

Cross-national comparison of socioeconomic inequalities in obesity in the United States and Canada.

INTRODUCTION: Prior cross-national studies of socioeconomic inequalities in obesity have only compared summary indices of inequality but not specific, policy-relevant dimensions of inequality: (a) shape of the socioeconomic gradient in obesity, (b) magnitude of differentials in obesity across socioeconomic levels and, (c) level of obesity at any given socioeconomic level. We use unique data on two highly comparable societies - U.S. and Canada - to contrast each of these inequality dimensions. METHODS: Data came from the 2002/2003 Joint Canada/U.S. Survey of Health. We calculated adjusted prevalence ratios (APRs) for obesity (compared to normal weight) by income quintile and education group separately for both nations and, between Canadians and Americans in the same income or education group. RESULTS: In the U.S., every socioeconomic group except the college educated had significant excess prevalence of obesity. By contrast in Canada, only those with less than high school were worse off, suggesting that the shape of the socioeconomic gradient differs in the two countries. U.S. differentials between socioeconomic levels were also larger than in Canada (e.g., PR quintile 1 compared to quintile 5 was 1.82 in the U.S. [95 % CI: 1.52-2.19] but 1.45 in Canada [95 % CI: 1.10-1.91]). At the lower end of the socioeconomic gradient, obesity was more prevalent in the U.S. than in Canada. CONCLUSIONS: Our results suggest there is variation between U.S. and Canada in different dimensions of socioeconomic inequalities in obesity. Future research should examine a broader set of nations and test whether specific policies or environmental exposures can explain these differences.

Acute responses to opioidergic blockade as a biomarker of hedonic eating among obese women enrolled in a mindfulness-based weight loss intervention trial.

There are currently no commonly used or easily accessible 'biomarkers' of hedonic eating. Physiologic responses to acute opioidergic blockade, indexed by cortisol changes and nausea, may represent indirect functional measures of opioid-mediated hedonic eating drive and predict weight loss following a mindfulness-based intervention for stress eating. In the current study, we tested whether cortisol and nausea responses induced by oral ingestion of an opioidergic antagonist (naltrexone) correlated with weight and self-report measures of hedonic eating and predicted changes in these measures following a mindfulness-based weight loss intervention. Obese women (N = 88; age = 46.7 ± 13.2 years; BMI = 35.8 ± 3.8) elected to complete an optional sub-study prior to a 5.5-month weight loss intervention with or without mindfulness training. On two separate days, participants ingested naltrexone and placebo pills, collected saliva samples, and reported nausea levels. Supporting previous findings, naltrexone-induced cortisol increases were associated with greater hedonic eating (greater food addiction symptoms and reward-driven eating) and less mindful eating. Among participants with larger cortisol increases (+1 SD above mean), mindfulness participants (relative to control participants) reported greater reductions in food addiction symptoms, b = -0.95, SE(b) = 0.40, 95% CI [-1.74, -0.15], p = .021. Naltrexone-induced nausea was marginally associated with reward-based eating. Among participants who endorsed naltrexone-induced nausea (n = 38), mindfulness participants (relative to control participants) reported greater reductions in food addiction symptoms, b = -1.00, 95% CI [-1.85, -0.77], p = .024, and trended toward reduced reward-based eating, binge eating, and weight, post-intervention. Single assessments of naltrexone-induced cortisol increases and nausea responses may be useful time- and cost-effective biological markers to identify obese individuals with greater opioid-mediated hedonic eating drive who may benefit from weight loss interventions with adjuvant mindfulness training that targets hedonic eating.

Excessive Sugar Consumption May Be a Difficult Habit to Break: A View From the Brain and Body.

CONTEXT: Sugar overconsumption and chronic stress are growing health concerns because they both may increase the risk for obesity and its related diseases. Rodent studies suggest that sugar consumption may activate a glucocorticoid-metabolic-brain-negative feedback pathway, which may turn off the stress response and thereby reinforce habitual sugar overconsumption. OBJECTIVE: The objective of the study was to test our hypothesized glucocorticoid-metabolic-brain model in women consuming beverages sweetened with either aspartame of sucrose. DESIGN: This was a parallel-arm, double-masked diet intervention study. SETTING: The study was conducted at the University of California, Davis, Clinical and Translational Science Center's Clinical Research Center and the University of California, Davis, Medical Center Imaging Research Center. PARTICIPANTS: Nineteen women (age range 18-40 y) with a body mass index (range 20-34 kg/m(2)) who were a subgroup from a National Institutes of Health-funded investigation of 188 participants assigned to eight experimental groups. INTERVENTION: The intervention consisted of sucrose- or aspartame-sweetened beverage consumption three times per day for 2 weeks. MAIN OUTCOME MEASURES: Salivary cortisol and regional brain responses to the Montreal Imaging Stress Task were measured. RESULTS: Compared with aspartame, sucrose consumption was associated with significantly higher activity in the left hippocampus (P = .001). Sucrose, but not aspartame, consumption associated with reduced (P = .024) stress-induced cortisol. The sucrose group also had a lower reactivity to naltrexone, significantly (P = .041) lower nausea, and a trend (P = .080) toward lower cortisol. CONCLUSION: These experimental findings support a metabolic-brain-negative feedback pathway that is affected by sugar and may make some people under stress more hooked on sugar and possibly more vulnerable to obesity and its related conditions.