Defining Spatial Epidemiology: A Systematic Review and Re-Orientation

BACKGROUND

Spatial epidemiology has emerged as an important subfield of epidemiology over the past quarter century. We trace the origins of spatial epidemiology and note that its emergence coincided with technological developments in spatial statistics and geography. We hypothesize that spatial epidemiology makes important contributions to descriptive epidemiology and analytic risk factor studies, but is not yet aligned with epidemiology's current focus on causal inference and intervention.

METHODS

We conducted a systematic review of studies indexed in PubMed that used the term "spatial epidemiolog*" in the title, abstract, or keywords. Excluded papers were not written in English, examined disease in animals, or reported biologic pathogen distribution only. We coded the included papers into five categories (review, demonstration of method, descriptive, analytic, intervention) and recorded the unit of analysis (i.e., individual vs. ecological). We additionally examined papers coded as analytic ecologic studies using scales for lexical content.

RESULTS

A total of 482 papers met the inclusion criteria, including 76 reviews, 117 demonstrations of methods, 122 descriptive studies, 167 analytic studies, and 0 intervention studies. Demonstration studies were most common from 2006 to 2014, and analytic studies were most common after 2015. Among the analytic ecologic studies, those published in later years used more terms relevant to spatial statistics (IRR =1.3, 95%CI: 1.1, 1.5) and causal inference (IRR =1.1, 95%CI: 1.1, 1.2).

CONCLUSIONS

Spatial epidemiology is an important and growing subfield of epidemiology. We suggest a re-orientation to help align its practice with the goals of contemporary epidemiology.

Longitudinal profiles of neighborhood socioeconomic vulnerability influence blood pressure changes across the female midlife period

PURPOSE

To examine whether longitudinal exposure to neighborhood socioeconomic vulnerability influences blood pressure changes throughout midlife in a racially, ethnically, and geographically-diverse cohort of women transitioning through menopause.

METHODS

We used longitudinal data on 2738 women (age 42-52 at baseline) living in six United States cities from The Study of Women's Health Across the Nation. Residential histories, systolic blood pressures (SBP), and diastolic blood pressures (DBP) were collected annually for ten years. We used longitudinal latent profile analysis to identify patterns of neighborhood socioeconomic vulnerability occurring from 1996 to 2007 in participant neighborhoods. We used linear mixed-effect models to determine if a woman's neighborhood profile throughout midlife was associated with blood pressure changes.

RESULTS

We identified four unique profiles of neighborhood socioeconomic vulnerability - differentiated by residential socioeconomic status, population density, and vacant housing conditions - which remained stable across time. Women residing in the most socioeconomically vulnerable neighborhoods experienced the steepest increase in annual SBP growth by 0.93 mmHg/year (95% CI: 0.65-1.21) across ten-year follow-up.

CONCLUSIONS

Neighborhood socioeconomic vulnerability was significantly associated with accelerated SBP increases throughout midlife among women.

North to south gradient and local waves of influenza in Chile

Influenza seasonality is caused by complex interactions between environmental factors, viral mutations, population crowding, and human travel. To date, no studies have estimated the seasonality and latitudinal patterns of seasonal influenza in Chile. We obtained influenza-like illness (ILI) surveillance data from 29 Chilean public health networks to evaluate seasonality using wavelet analysis. We assessed the relationship between the start, peak, and latitude of the ILI epidemics using linear and piecewise regression. To estimate the presence of incoming and outgoing traveling waves (timing vs distance) between networks and to assess the association with population size, we used linear and logistic regression. We found a north to south gradient of influenza and traveling waves that were present in the central, densely populated region of Chile. Our findings suggest that larger populations in central Chile drive seasonal influenza epidemics.

Understanding Polarizing Community Perspectives on Harm Reduction Strategies: Challenges to Addressing the Opioid Crisis in Appalachian Pennsylvania

Introduction

Rural communities face barriers to opioid treatment and overdose prevention including concerns about stigma and lack of harm reduction services.

Purpose

The aim of this study was to explore community perspectives and understanding of harm reduction approaches to opioid use and overdose in a high-risk Northern Appalachian case community in Pennsylvania.

Methods

A small town approximately 10 miles from Pittsburgh was identified as the community with the greatest predicted probabilities of epidemic outbreak using posteriors from spatial models of hospitalizations for opioid use disorders. We interviewed 20 key stakeholders in the case community in using a semi-structured interview guide and analyzed the qualitative data using an inductive grounded theory approach.

Results

Our findings illustrate how conflicting perspectives about opioid dependence lay the foundation for the polarizing community perspectives on addressing opioid use and overdose and general disagreement regarding the legitimacy of harm reduction approaches versus abstinence-based recovery plans. Community members shared varying perspectives on multiple aspects of the opioid epidemic, including appropriate strategies, treatment, and overdose prevention methods and how community leaders and organizations should respond.

Implications

Opinions, coupled with a general lack of education regarding opioid use and harm reduction options, make it challenging for small communities with limited resources to create comprehensive plans to address the opioid crisis.

Drivers of opioid use in Appalachian Pennsylvania: Cross-cutting social and community-level factors

BACKGROUND

Four Appalachian states including Pennsylvania (PA) have the highest drug overdose rates in the country, calling for better understanding of the social and economic drivers of opioid use in the region. Using key informant interviews, we explored the social and community drivers of opioid use in a non-urban Appalachian Pennsylvania community.

METHODS

In 2017, we conducted qualitative interviews with 20 key stakeholders from a case community selected using the results from quantitative spatial models of hospitalizations for opioid use disorders. In small town located 10 miles outside Pittsburgh, PA, we asked participants to share their perceptions of contextual factors that influence opioid use among residents. We then used qualitative thematic analysis to organize and generate the results.

RESULTS

Participants identified several contextual factors that influence opioid use among residents. Three cross-cutting thematic topics emerged: 1) acceptance and denial of use through familial and peer influences, community environments, and social norms; 2) impacts of economic shifts and community leadership on availability of programs and opportunities; and 3) the role of coping within economic disadvantage and social depression.

CONCLUSION

Uncovering multi-level, contextual drivers of opioid use can benefit the development of future public health interventions. These results suggest that social and community-level measures of structural deprivation, acceptance and/or denial of the opioid epidemic, community engagement and development, social support, and social depression are important for future research and programmatic efforts in the Appalachian region.

Introduction to the Theme Issue on Dynamics of Health Behavior: Revisiting Systems Science for Population Health

Systems science can help public health professionals to better understand the complex dynamics between factors affecting health behaviors and outcomes and to identify intervention opportunities. Despite their demonstrated utility in addressing health topics such influenza, tobacco control, and obesity, the associated methods continue to be underutilized by researchers and practitioners addressing health behaviors. This article discusses the growth of systems science methods (e.g., system dynamics, social network analysis, and agent-based modeling) in health research, provides a frame for the articles included in this themed issue, and closes with recommendations for enhancing the future of systems science and health behavior research. We argue that integrating systems sciences methods into health behavior research and practice is essential for improved population health and look forward to supporting the evolution of the field.

Adolescent drinking in different contexts: What behaviors do parents control?

Previous research suggests that the context in which drinking occurs contribute to specific alcohol-related problems. In the current study we assessed how often adolescents attended different contexts in which they could drink, how often they drank in those contexts, and whether drinking patterns and parental monitoring were related to alcohol use in those contexts. We collected survey data from 1,217 adolescents 15-18 years of age in 24 midsized California cities. Measures included past-year frequencies of attending and drinking in restaurants, bars/nightclubs, and outdoor places, typical hours spent at home (i.e., own home or someone else's home), perceptions of parental control and disclosure to parents about free time activities, and demographics. Multilevel zero-inflated negative binomial models were used to assess associations between drinking patterns, parental control, and disclosure and frequency of attending and drinking in specific contexts. There were large variations in attending contexts in which drinking could take place. More frequent drinking was related to less time spent at home, while heavier drinking was associated with more time spent at home. Parental control was related to less frequent attendance at bars/nightclubs, and disclosure to less frequent involvement in outdoor activities and spending more time at home. Among drinkers, frequencies of attendance were strongly related to frequencies of drinking in all contexts except the home. Parental control and disclosure were related to more frequent drinking at restaurants and exposure to bars/nightclubs and drinking at outdoor activities. Parental monitoring may reduce exposure to risks by shifting adolescent contexts for alcohol use.

Are Barroom and Neighborhood Characteristics Independently Related to Local-Area Assaults?

BACKGROUND

Two separate but complementary literatures examine bar-related violence: one has focused on barroom features, and the other has focused on features of neighborhoods near bars. This study unifies these 2 perspectives using a microenvironmental approach.

METHODS

In a purposive sample of 65 bars in 4 California cities, we used premise assessments to characterize the physical, social, and economic environments of barrooms (e.g., patron count, average pace of drinking, and restaurant service); and a combination of systematic social observation, census, and alcohol license data to characterize the neighborhoods in which they were located (e.g., physical disorder, alcohol outlet density, and median household income). Hierarchical Poisson models then assessed relationships between these features and counts of police-reported assaults within buffer areas around bars.

RESULTS

Aspects of both barroom environments (more patrons, more dancing, and louder music) and neighborhood environments (greater bar density, greater physical disorder, lower population density, and lower income) were independently related to increased incidence of assaults.

CONCLUSIONS

Preventive intervention to reduce bar-area violence may be directed at both bar environments (e.g., limiting the number of patrons) and neighborhood environments (e.g., limiting outlet density).

Who drinks where: youth selection of drinking contexts

BACKGROUND

Different drinkers may experience specific risks depending on where they consume alcohol. This longitudinal study examined drinking patterns, and demographic and psychosocial characteristics associated with youth drinking in different contexts.

METHODS

We used survey data from 665 past-year alcohol-using youths (ages 13 to 16 at Wave 1) in 50 midsized California cities. Measures of drinking behaviors and drinking in 7 contexts were obtained at 3 annual time points. Other characteristics included gender, age, race, parental education, weekly disposable income, general deviance, and past-year cigarette smoking.

RESULTS

Results of multilevel regression analyses show that more frequent past-year alcohol use was associated with an increased likelihood of drinking at parties and at someone else's home. Greater continued volumes of alcohol (i.e., heavier drinking) was associated with increased likelihood of drinking at parking lots or street corners. Deviance was positively associated with drinking in most contexts, and past-year cigarette smoking was positively associated with drinking at beaches or parks and someone else's home. Age and deviance were positively associated with drinking in a greater number of contexts. The likelihood of youth drinking at parties and someone else's home increased over time, whereas the likelihood of drinking at parking lots/street corners decreased. Also, deviant youths progress to drinking in their own home, beaches or parks, and restaurants/bars/nightclubs more rapidly.

CONCLUSIONS

The contexts in which youths consume alcohol change over time. These changes vary by individual characteristics. The redistribution of drinking contexts over the early life course may contribute to specific risks associated with different drinking contexts.