A multi-stage approach to maximizing geocoding success in a large population-based cohort study through automated and interactive processes

Associations of neighborhood sociodemographic environment with mortality and circulating metabolites among low-income black and white adults living in the southeastern United States

BACKGROUND

Residing in a disadvantaged neighborhood has been linked to increased mortality. However, the impact of residential segregation and social vulnerability on cause-specific mortality is understudied. Additionally, the circulating metabolic correlates of neighborhood sociodemographic environment remain unexplored. Therefore, we examined multiple neighborhood sociodemographic metrics, i.e., neighborhood deprivation index (NDI), residential segregation index (RSI), and social vulnerability index (SVI), with all-cause and cardiovascular disease (CVD) and cancer-specific mortality and circulating metabolites in the Southern Community Cohort Study (SCCS).

METHODS

The SCCS is a prospective cohort of primarily low-income adults aged 40-79, enrolled from the southeastern United States during 2002-2009. This analysis included self-reported Black/African American or non-Hispanic White participants and excluded those who died or were lost to follow-up ≤ 1 year. Untargeted metabolite profiling was performed using baseline plasma samples in a subset of SCCS participants.

RESULTS

Among 79,631 participants, 23,356 deaths (7214 from CVD and 5394 from cancer) were documented over a median 15-year follow-up. Higher NDI, RSI, and SVI were associated with increased all-cause, CVD, and cancer mortality, independent of standard clinical and sociodemographic risk factors and consistent between racial groups (standardized HRs among all participants were 1.07 to 1.20 in age/sex/race-adjusted model and 1.04 to 1.08 after comprehensive adjustment; all P < 0.05/3 except for cancer mortality after comprehensive adjustment). The standard risk factors explained < 40% of the variations in NDI/RSI/SVI and mediated < 70% of their associations with mortality. Among 1110 circulating metabolites measured in 1688 participants, 134 and 27 metabolites were associated with NDI and RSI (all FDR < 0.05) and mediated 61.7% and 21.2% of the NDI/RSI-mortality association, respectively. Adding those metabolites to standard risk factors increased the mediation proportion from 38.4 to 87.9% and 25.8 to 42.6% for the NDI/RSI-mortality association, respectively.

CONCLUSIONS

Among low-income Black/African American adults and non-Hispanic White adults living in the southeastern United States, a disadvantaged neighborhood sociodemographic environment was associated with increased all-cause and CVD and cancer-specific mortality beyond standard risk factors. Circulating metabolites may unveil biological pathways underlying the health effect of neighborhood sociodemographic environment. More public health efforts should be devoted to reducing neighborhood environment-related health disparities, especially for low-income individuals.

Rurality and race in heart failure risk: Insights from the Southern Community Cohort Study

INTRODUCTION

Rural-urban health disparities are apparent in the burden of disease and health outcomes, including cardiovascular disease (CVD), specifically heart failure (HF). However, the factors influencing these disparities are not fully understood. Study and results: Among 27,115 participants in the Southern Community Cohort Study (SCCS) (mean age: 54 years (47-65)), 18,647 (68.8%) were black, 8,468 (32.3%) were white, and 20% resided in rural areas. Over a median 13-year follow-up period, 7,542 HF events occurred (rural = 1,865 vs. urban = 5,677). The age-adjusted HF incidence was 29.6 (95% CI, 28.9-30.5) and 36.5 (95% CI, 34.9-38.3) per 1,000 person-years for urban and rural participants, respectively (P < .001). The risk of HF associated with rurality varied by race and sex. Rural black men had the highest risk across all groups (HR, 1.34; 95% CI, 1.19-1.51) (age-adjusted incidence rate: 40.4/1000 person-years (95% CI, 36.8-44.3)) followed by black women (HR, 1.18; 95% CI, 1.08-1.28) and white women (HR, 1.22; 95% CI, 1.07-1.39). Rurality was not associated with HF risk among white men (HR, 0.97; 95% CI, 0.81-1.16).

LESSONS LEARNED

This large study shows that rural populations have an increased incidence of HF, which is particularly striking among women and black men, independent of individual-level biological, behavioral, and sociocultural risk factors. It also shows the need for further investigation into the rurality-associated risk of HF, the impact of preventive care utilization on the risk of HF and interpersonal, community, or societal factors that could contribute to rural-urban disparities. This will help to guide public health efforts aimed at HF prevention among rural populations.

Dietary medium-chain fatty acids and risk of incident colorectal cancer in a predominantly low-income population: a report from the Southern Community Cohort Study

BACKGROUND

No prospective observational study has specifically examined the associations between dietary intakes of medium-chain fatty acids and risk of colorectal cancer.

OBJECTIVES

This study examined the association between dietary intakes of medium-chain fatty acids and colorectal cancer risk overall and by racial subgroups in a predominantly low-income United States population.

METHODS

This prospective study included 71,599 eligible participants aged 40 to 79 who were enrolled in the Southern Community Cohort Study between 2002 and 2009 in 12 southeastern United States states. Incident colorectal cancer cases were ascertained via linkage to state cancer registries, which was completed through 31 December, 2016. The dietary intakes of medium-chain fatty acids were assessed using a validated 89-item food frequency questionnaire. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between intakes of medium-chain fatty acids and risk for incident colorectal cancer.

RESULTS

Among 71,599 participants, 48,008 (67.3%) were Black individuals and 42,260 (59.0%) were female. A total of 868 incident colorectal cancer cases occurred during a median follow-up of 13.7 y. Comparing the highest to the lowest quartile, high intake of dodecanoic acid/lauric acid (C12:0) was associated with reduced risk of colorectal cancer among White participants (HR: 0.52; 95% CI: 0.30, 0.91; P-trend = 0.05), but not in Black individuals (HR: 0.92; 95% CI, 0.68, 1.24; P-trend = 0.80) in multivariable-adjusted models. No associations were found between intakes of hexanoic acid/caproic acid (C6:0), octanoic acid/caprylic acid (C8:0), or decanoic acid/capric acid (C10:0) and risk of incident colorectal cancer overall or within racial subgroups.

CONCLUSIONS

In a predominantly low-income United States population, an increased dietary C12:0 intake was associated with a substantially reduced risk of colorectal cancer only among White individuals, but not in Black individuals.

Association of Rurality With Risk of Heart Failure

Importance

Rural populations experience an increased burden of heart failure (HF) mortality compared with urban populations. Whether HF incidence is greater among rural individuals is less known. Additionally, the intersection between racial and rural health inequities is understudied.

Objective

To determine whether rurality is associated with increased risk of HF, independent of cardiovascular (CV) disease and socioeconomic status (SES), and whether rurality-associated HF risk varies by race and sex.

Design, Setting, and Participants

This prospective cohort study analyzed data for Black and White participants of the Southern Community Cohort Study (SCCS) without HF at enrollment who receive care via Centers for Medicare & Medicaid Services (CMS). The SCCS is a population-based cohort of low-income, underserved participants from 12 states across the southeastern United States. Participants were enrolled between 2002 and 2009 and followed up until December 31, 2016. Data were analyzed from October 2021 to November 2022.

Exposures

Rurality as defined by Rural-Urban Commuting Area codes at the census-tract level.

Main Outcomes and Measures

Heart failure was defined using diagnosis codes via CMS linkage through 2016. Incidence of HF was calculated by person-years of follow-up and age-standardized. Sequentially adjusted Cox proportional hazards regression models tested the association between rurality and incident HF.

Results

Among 27 115 participants, the median (IQR) age was 54 years (47-65), 18 647 (68.8%) were Black, and 8468 (32.3%) were White; 5556 participants (20%) resided in rural areas. Over a median 13-year follow-up, age-adjusted HF incidence was 29.6 (95% CI, 28.9-30.5) per 1000 person-years for urban participants and 36.5 (95% CI, 34.9-38.3) per 1000 person-years for rural participants (P < .001). After adjustment for demographic information, CV risk factors, health behaviors, and SES, rural participants had a 19% greater risk of incident HF (hazard ratio [HR], 1.19; 95% CI, 1.13-1.26) compared with their urban counterparts. The rurality-associated risk of HF varied across race and sex and was greatest among Black men (HR, 1.34; 95% CI, 1.19-1.51), followed by White women (HR, 1.22; 95% CI, 1.07-1.39) and Black women (HR, 1.18; 95% CI, 1.08-1.28). Among White men, rurality was not associated with greater risk of incident HF (HR, 0.97; 95% CI, 0.81-1.16).

Conclusions and Relevance

Among predominantly low-income individuals in the southeastern United States, rurality was associated with an increased risk of HF among women and Black men, which persisted after adjustment for CV risk factors and SES. This inequity points to a need for additional emphasis on primary prevention of HF among rural populations.

Racial Disparities in Associations of Alcohol Consumption With Liver Disease Mortality in a Predominantly Low-Income Population: A Report From the Southern Community Cohort Study

Consistent with previous cross-sectional studies, in the Southern Community Cohort Study, the largest cohort for Black Americans conducted in a predominantly low-income population with 81,694 participants, we found that moderate alcohol drinking was associated with a significantly increased risk of mortality due to liver disease in Black Americans (hazard ratio = 2.06; 95% confidence interval: 1.08-3.94) but not in White Americans (hazard ratio = 0.87; 95% confidence interval: 0.52-1.44). We found that heavy drinking was significantly associated with an increased risk of mortality due to liver disease in both Black and White Americans. Future studies are warranted to understand the mechanism involving such racial disparity.

Uncertainty in geospatial health: challenges and opportunities ahead

PURPOSE

Uncertainty is not always well captured, understood, or modeled properly, and can bias the robustness of complex relationships, such as the association between the environment and public health through exposure, estimates of geographic accessibility and cluster detection, to name a few.

METHODS

We review current challenges and future opportunities as geospatial data and analyses are applied to the field of public health. We are particularly interested in the sources of uncertainty in geospatial data and how this uncertainty may propagate in spatial analysis.

RESULTS

We present opportunities to reduce the magnitude and impact of uncertainty. Specifically, we focus on (1) the use of multiple reference data sources to reduce geocoding errors, (2) the validity of online geocoders and how confidentiality (e.g., HIPAA) may be breached, (3) use of multiple reference data sources to reduce geocoding errors, (4) the impact of geoimputation techniques on travel estimates, (5) residential mobility and how it affects accessibility metrics and clustering, and (6) modeling errors in the American Community Survey. Our paper discusses how to communicate spatial and spatiotemporal uncertainty, and high-performance computing to conduct large amounts of simulations to ultimately increase statistical robustness for studies in public health.

CONCLUSIONS

Our paper contributes to recent efforts to fill in knowledge gaps at the intersection of spatial uncertainty and public health.

Neighborhood variation in unsolved homicides: a retrospective cohort study in Indianapolis, Indiana, 2007-2017

BACKGROUND

Homicide is a widely acknowledged public health problem in the United States. The majority of homicides are committed with a firearm and have long-term health consequences for family members and entire communities. When left unsolved, violence may be perpetuated due to the retaliatory nature of homicides. Improving homicide clearance rates may help prevent future violence, however, we know little about the community-level social dynamics associated with unsolved homicides.

METHODS

This study examines the individual-and-community-level social processes associated with low homicide clearance rates in Indianapolis, Indiana between 2007 and 2017. Homicide clearance is the primary outcome, defined as if a perpetrator was arrested for that homicide case between 2007 and 2017. Individual-level variables include the victim's race/ethnicity, sex, and age. Community-level (i.e., census tracts) variables include the number of resident complaints against the police, resident complains of community disorder, income inequality, number of police interactions, and proportion of African American residents.

RESULTS

In Indianapolis over a 11-year period, the homicide clearance rate decreased to a low of 38% in 2017, compared to a national clearance rate of 60%. Homicide case clearance was less likely for minority (OR 0.566; 95% CI, 0.407-0.787; p < 0.01) and male (OR 0.576; 95% CI, 0.411-0.807; p < 0.01) victims. Resident complaints of community disorder were associated with a decreased odds of case clearance (OR 0.687; 95% CI, 0.485-0.973; p < .01)., African American victim's cases were less likely to be cleared in 2014-2017 (OR 0.640; 95% CI, 0.437-0.938; p < 0.05), compared to 2007.

CONCLUSIONS

Our study identified differences in neighborhood social processes associated with homicide clearance, indicating existing measures on these community factors are complex. Programs aimed at improving signs of community disorder and building community engagement may improve neighborhood clearance rates, lower violence, and improve the health of these communities.

Supports and Barriers to Home-Based Physical Activity During Preoperative Treatment of Pancreatic Cancer: A Mixed-Methods Study

BACKGROUND

Physical activity and exercise appear to benefit patients receiving preoperative treatment for cancer. Supports and barriers must be considered to increase compliance with home-based exercise prescriptions in this setting. Such influences have not been previously examined.

METHODS

The authors used quantitative and qualitative methods to examine potential physical activity influences among patients who were prescribed home-based aerobic and strengthening exercises concurrent with preoperative chemotherapy or chemoradiation for pancreatic cancer. Physical activity was measured using exercise logs and accelerometers. Social support for exercise and perceived neighborhood walkability were measured using validated surveys. Relationships between influences and physical activity were evaluated using linear regression analyses and qualitative interviews.

RESULTS

Fifty patients received treatment for a mean of 16 (9) weeks prior to planned surgical resection. Social support from friends and neighborhood esthetics were positively associated with physical activity (P < .05). In interviews, patients confirmed the importance of these influences and cited encouragement from health care providers and desire to complete and recover from treatment as additional motivators.

CONCLUSIONS

Interpersonal and environmental motivators of exercise and physical activity must be considered in the design of future home-based exercise interventions designed for patients receiving preoperative therapy for cancer.

Ovarian Cancer in Women of African Ancestry (OCWAA) consortium: a resource of harmonized data from eight epidemiologic studies of African American and white women

PURPOSE

Although the incidence rate of epithelial ovarian cancer (EOC) is somewhat lower in African American (AA) than white women, survival is worse. The Ovarian Cancer in Women of African Ancestry (OCWAA) consortium will overcome small, study-specific sample sizes to better understand racial differences in EOC risk and outcomes.

METHODS

We harmonized risk factors and prognostic characteristics from eight U.S.

STUDIES

the North Carolina Ovarian Cancer Study (NCOCS), the Los Angeles County Ovarian Cancer Study (LACOCS), the African American Cancer Epidemiology Study (AACES), the Cook County Case-Control Study (CCCCS), the Black Women's Health Study (BWHS), the Women's Health Initiative (WHI), the Multiethnic Cohort Study (MEC), and the Southern Community Cohort Study (SCCS).

RESULTS

Determinants of disparities for risk and survival in 1,146 AA EOC cases and 2,922 AA controls will be compared to 3,368 white EOC cases and 10,270 white controls. Analyses include estimation of population-attributable risk percent (PAR%) by race.

CONCLUSION

OCWAA is uniquely positioned to study the epidemiology of EOC in AA women compared with white women to address disparities. Studies of EOC have been underpowered to address factors that may explain AA-white differences in the incidence and survival. OCWAA promises to provide novel insight into disparities in ovarian cancer.

Neighborhood Deprivation Predicts Heart Failure Risk in a Low-Income Population of Blacks and Whites in the Southeastern United States

BACKGROUND

Recent data suggest that neighborhood socioeconomic environment predicts heart failure (HF) hospital readmissions. We investigated whether neighborhood deprivation predicts risk of incident HF beyond individual socioeconomic status in a low-income population.

METHODS AND RESULTS

Participants were 27 078 whites and blacks recruited during 2002 to 2009 in the SCCS (Southern Community Cohort Study), who had no history of HF and were using Centers for Medicare or Medicaid Services. Incident HF diagnoses through December 31, 2010, were ascertained using International Classification of Diseases, Ninth Revision, codes 428.x via linkage with Centers for Medicare or Medicaid Services research files. Participant residential information was geocoded and census tract determined by a spatial join to the US Census Bureau TIGER/Line Shapefiles. The neighborhood deprivation index was constructed using principal components analysis based on census tract-level socioeconomic variables. Cox models with Huber-White cluster sandwich estimator of variance were used to investigate the association between neighborhood deprivation index and HF risk. The study sample was predominantly middle aged (mean, 55.5 years), black (69%), female (63%), low income (70% earned <$15 000/y), and >50% of participants lived in the most deprived neighborhoods (third neighborhood deprivation index tertile). Over median follow-up of 5.2 years, 4300 participants were diagnosed with HF. After adjustment for demographic, lifestyle, and clinical factors, a 1 interquartile increase in neighborhood deprivation index was associated with a 12% increase in risk of HF (hazard ratio, 1.12; 95% confidence interval, 1.07-1.18), and 4.8% of the variance in HF risk (intraclass correlation coefficient, 4.8; 95% confidence interval, 3.6-6.4) was explained by neighborhood deprivation.

CONCLUSIONS

In this low-income population, scant neighborhood resources compound the risk of HF above and beyond individual socioeconomic status and traditional cardiovascular risk factors. Improvements in community resources may be a significant axis for curbing the burden of HF.

Does religious involvement affect mortality in low-income Americans? A prospective cohort study

OBJECTIVE

This study aimed to evaluate the impacts of various forms of religious involvement, beyond individual socioeconomic status, lifestyle factors, emotional well-being and social support, on all-cause and cause-specific mortality in socioeconomic disadvantaged neighbourhoods.

DESIGN

This is a prospective cohort study conducted from 2002 through 2015.

SETTINGS

This study included underserved populations in the Southeastern USA.

PARTICIPANTS

A total of nearly 85 000 participants, primarily low-income American adults, were enrolled. Eligible participants were aged 40-79 years at enrolment, spoke English and were not under treatment for cancer within the prior year.

RESULTS

We found that those who attended religious service attendance >1/week had 8% reduction in all-cause death and 15% reduction in cancer death relative to those who never attended. This association was substantially attenuated by depression score, social support, and socioeconomic and lifestyle covariates, and further attenuated by other forms of religious involvement. This association with all-cause mortality was found being stronger among those with higher socioeconomic status or healthier lifestyle behaviours.

CONCLUSION

Our results indicate that the association between religious services attendance >1/week and lower mortality was moderate but robust, and could be attenuated and modified by socioeconomic or lifestyle factors in this large prospective cohort study of underserved populations in the Southeastern USA.

Neighbourhood deprivation and lung cancer risk: a nested case-control study in the USA

OBJECTIVES

To examine the association between neighbourhood deprivation and lung cancer risk.

DESIGN

Nested case-control study.

SETTING

Southern Community Cohort Study of persons residing in 12 states in the southeastern USA.

PARTICIPANTS

1334 cases of lung cancer and 5315 controls.

PRIMARY OUTCOME MEASURE

Risk of lung cancer.

RESULTS

After adjustment for smoking status and other confounders, and additional adjustment for individual-level measures of socioeconomic status (SES), there was no monotonic increase in risk with worsening deprivation score overall or within sex and race groups. There was an increase among current and shorter term former smokers (p=0.04) but not among never and longer term former smokers. There was evidence of statistically significant interaction by sex among whites, but not blacks, in which the effect of worsening deprivation on lung cancer existed in males but not in females.

CONCLUSIONS

Area-level measures of SES were associated with lung cancer risk in current and shorter term former smokers only in this population.

Associations Between Neighborhood Environment, Health Behaviors, and Mortality

INTRODUCTION

Considering the joint association of neighborhood socioeconomic environment and individual-level health behaviors with health outcomes may help officials design effective disease prevention strategies. This study evaluates the joint influences of neighborhood socioeconomic environment and individual health behaviors on mortality in a cohort primarily comprising people with low individual-level SES.

METHODS

The prospective Southern Community Cohort Study includes 77,896 white and African American participants recruited in the years 2002-2009; 55% of participants had a household income <$15,000 at baseline interview. Mortality from cancer (n=2,471), cardiovascular diseases (n=3,005), and all-causes (n=10,099) was identified from the National Death Index through December 31, 2013 (median follow-up, 8 years). Data were analyzed in 2016 and 2017. Associations were assessed between mortality, a neighborhood deprivation index composed of 11 census tract-level variables, five health behaviors, and a composite healthy lifestyle score.

RESULTS

Living in a neighborhood with the greatest socioeconomic disadvantage was associated with higher all-cause mortality in both men (hazard ratio=1.41, 95% CI=1.27, 1.57) and women (hazard ratio=1.77, 95% CI=1.57, 2.00). Associations were attenuated after adjustment for individual-level SES and major risk factors (hazard ratio for men=1.09, 95% CI=0.98, 1.22, and hazard ratio for women=1.26, 95% CI=1.12, 1.42). The dose-response association between neighborhood disadvantage and mortality was less apparent among smokers. Nevertheless, individuals who lived in disadvantaged neighborhoods and had the unhealthiest lifestyle scores experienced the highest mortality.

CONCLUSIONS

Disadvantaged neighborhood socioeconomic environments are associated with increased mortality in a cohort of individuals of low SES. Positive individual-level health behaviors may help negate the adverse effect of disadvantage on mortality.

Travel Time Influences Readmission Risk: Geospatial Mapping of Surgical Readmissions

The University of Virginia (UVA) has recently become an Accountable Care Organization (ACO), intensifying efforts to provide better care for individuals. UVA's ACO population resides across the entire Commonwealth, with a large percentage of patients living in rural areas. To provide better health for this population, the central tenet of the ACO mission, we identified geographic risk factors influencing hospital readmission. We analyzed the relationship between the distance of patients’ residence to the nearest hospital and 30-day readmission in general surgery patients. A retrospective chart review using January 1, 2011 through October 31, 2013 American College of Surgeons National Surgical Quality Improvement Program data for general surgery procedures was conducted. ArcGIS mapped street addresses provided graphical representation of distance between surgical population and the nearest hospital. We analyzed the impact on readmission, of time traveled, insurance status, and median household income. Each increase of 10 minutes in travel time from the patient's residence to the nearest hospital, not just UVA, was associated with a 9 per cent increase in the probability of readmission after adjusting for patient characteristics, preoperative comorbidities, laboratory values, and postoperative complications before or after discharge (odds ratio = 1.09; 95% confidence interval = 1.01–1.17; P = 0.019). Unlike urban hospitals, those serving rural populations may be at particular risk of postsurgical readmissions. Patients living furthest from a hospital facility are most at risk for readmission after a general surgery procedure. This vulnerable population may benefit most from comprehensive discharge planning.

Accuracy of two geocoding methods for geographic information system-based exposure assessment in epidemiological studies

BACKGROUND

Environmental exposure assessment based on Geographic Information Systems (GIS) and study participants' residential proximity to environmental exposure sources relies on the positional accuracy of subjects' residences to avoid misclassification bias. Our study compared the positional accuracy of two automatic geocoding methods to a manual reference method.

METHODS

We geocoded 4,247 address records representing the residential history (1990-2008) of 1,685 women from the French national E3N cohort living in the Rhône-Alpes region. We compared two automatic geocoding methods, a free-online geocoding service (method A) and an in-house geocoder (method B), to a reference layer created by manually relocating addresses from method A (method R). For each automatic geocoding method, positional accuracy levels were compared according to the urban/rural status of addresses and time-periods (1990-2000, 2001-2008), using Chi Square tests. Kappa statistics were performed to assess agreement of positional accuracy of both methods A and B with the reference method, overall, by time-periods and by urban/rural status of addresses.

RESULTS

Respectively 81.4% and 84.4% of addresses were geocoded to the exact address (65.1% and 61.4%) or to the street segment (16.3% and 23.0%) with methods A and B. In the reference layer, geocoding accuracy was higher in urban areas compared to rural areas (74.4% vs. 10.5% addresses geocoded to the address or interpolated address level, p < 0.0001); no difference was observed according to the period of residence. Compared to the reference method, median positional errors were 0.0 m (IQR = 0.0-37.2 m) and 26.5 m (8.0-134.8 m), with positional errors <100 m for 82.5% and 71.3% of addresses, for method A and method B respectively. Positional agreement of method A and method B with method R was 'substantial' for both methods, with kappa coefficients of 0.60 and 0.61 for methods A and B, respectively.

CONCLUSION

Our study demonstrates the feasibility of geocoding residential addresses in epidemiological studies not initially recorded for environmental exposure assessment, for both recent addresses and residence locations more than 20 years ago. Accuracy of the two automatic geocoding methods was comparable. The in-house method (B) allowed a better control of the geocoding process and was less time consuming.

Built Environment and Depression in Low-Income African Americans and Whites

INTRODUCTION

Urban environments are associated with a higher risk of adverse mental health outcomes; however, it is unclear which specific components of the urban environment drive these associations.

METHODS

Using data collected in 2002-2009 from 73,225 low-income, racially diverse individuals across the Southeastern U.S., analyses evaluated the cross-sectional relationship between a walkability index and depression. Walkability was calculated from population density, street connectivity, and destination count in the 1,200-meter area around participants' homes, and depression was measured using the Center for Epidemiologic Studies Depression Scale for depression symptomatology and questionnaire responses regarding doctor-diagnosed depression and antidepressant use. Data were analyzed in 2015.

RESULTS

Participants living in neighborhoods with the highest walkability index had 6% higher odds of moderate or greater depression symptoms (score ≥15, 95% CI=0.99, 1.14), 28% higher odds of doctor-diagnosed depression (95% CI=1.20, 1.36), and 16% higher odds of current antidepressant use (95% CI=1.08, 1.25), compared with those in the lowest walkability index. Higher walkability was associated with higher odds of depression symptoms in the most deprived neighborhoods only, whereas walkability was associated with lower odds of depression symptoms in the least deprived neighborhoods.

CONCLUSIONS

Living in a more walkable neighborhood was associated with modestly higher levels of doctor-diagnosed depression and antidepressant use, and walkability was associated with greater depression symptoms in neighborhoods with higher deprivation. Although dense urban environments may provide opportunities for physical activity, they may also increase exposure to noise, air pollution, and social stressors that could increase levels of depression.

Spatializing 6,000 years of global urbanization from 3700 BC to AD 2000

How were cities distributed globally in the past? How many people lived in these cities? How did cities influence their local and regional environments? In order to understand the current era of urbanization, we must understand long-term historical urbanization trends and patterns. However, to date there is no comprehensive record of spatially explicit, historic, city-level population data at the global scale. Here, we developed the first spatially explicit dataset of urban settlements from 3700 BC to AD 2000, by digitizing, transcribing, and geocoding historical, archaeological, and census-based urban population data previously published in tabular form by Chandler and Modelski. The dataset creation process also required data cleaning and harmonization procedures to make the data internally consistent. Additionally, we created a reliability ranking for each geocoded location to assess the geographic uncertainty of each data point. The dataset provides the first spatially explicit archive of the location and size of urban populations over the last 6,000 years and can contribute to an improved understanding of contemporary and historical urbanization trends.

Socioeconomic status, race, and mortality: a prospective cohort study

OBJECTIVES

We evaluated the independent and joint effects of race, individual socioeconomic status (SES), and neighborhood SES on mortality risk.

METHODS

We conducted a prospective analysis involving 52 965 non-Hispanic Black and 23 592 non-Hispanic White adults taking part in the Southern Community Cohort Study. Cox proportional hazards modeling was used to determine associations of race and SES with all-cause and cause-specific mortality.

RESULTS

In our cohort, wherein Blacks and Whites had similar individual SES, Blacks were less likely than Whites to die during the follow-up period (hazard ratio [HR] = 0.78; 95% confidence interval [CI] = 0.73, 0.84). Low household income was a strong predictor of all-cause mortality among both Blacks and Whites (HR = 1.76; 95% CI = 1.45, 2.12). Being in the lowest (vs highest) category with respect to both individual and neighborhood SES was associated with a nearly 3-fold increase in all-cause mortality risk (HR = 2.76; 95% CI = 1.99, 3.84). There was no significant mortality-related interaction between individual SES and neighborhood SES among either Blacks or Whites.

CONCLUSIONS

SES is a strong predictor of premature mortality, and the independent associations of individual SES and neighborhood SES with mortality risk are similar for Blacks and Whites.