Dr. David Schlundt. Associate Professor Vanderbilt University

Transcription

1 Dr. David Schlundt Associate Professor Vanderbilt University

2 Strategies for studying person-environment transactions: Implications for understanding and preventing obesity David G. Schlundt, Ph.D. Associate Professor of Psychology Vanderbilt University Nashville, TN 2014 Southeastern Conference Symposium September, Hyatt Regency Atlanta, Georgia

3 Overview The obesity epidemic in time and space Shortcomings of: Biogenetic explanations Individual psychological and behavioral explanations Alternative Person-environment interaction framework Complex systems theory Research challenge studying personenvironment transactions Technologies/methodologies GIS Geographic Information Systems GPS Global Positioning Systyem EMA Ecological Momentary Assessment

4 Change over time is rapid, distribution in space is uneven Obesity Trends* Among U.S. Adults BRFSS, 1990, 2000, 2010 (*BMI 30, or about 30 lbs. overweight for 5 4 person) No Data <10% 10% 14% 15% 19% 20% 24% 25% 29% 30%

5 Nashville data Rapid increase in prevalence of obesity Differences in prevalence by place Large racial and ethnic disparities Consistent with changes in eating and exercise behaviors Note large neighborhood differences in Nashville

6 Strong association between housing quality and obesity/diabetes prevalence

7 Critique obesity as an individual clinical problem Biomedical model Biogenetic explanations obesity as disease Driven by clinical paradigm (individual diagnosis and treatment) Emphasis on drugs and surgery Is this how the world works? Psychological approaches Search for determinants of individual behavior Analysis at the level of individual (personality, emotion, cognition, and behavior) Behavioral treatments reinforce the clinical paradigm Reductionism Breaks problems down into smaller and smaller pieces Isolates single independent and dependent variables Takes systems and pathways out of context One cause one cure thinking Searching for the Cause of obesity within the individual is missing the big picture Searching for the Cure for obesity by treating the individual is missing the big picture

8 Alternative Frameworks Human behavior equations Theories of person-environment transaction Social cognitive theory Biopsychosocial approach Social ecological framework Complex systems theory Individual embedded in multi-level adaptive systems Whole is great than sum of its parts Must study the person in context B = behavior P = Person E = Environment Organismic B = f(p) Environmentalism B = f(e) Interactionism B = f(p,e) Kurt Lewin (1936) Principles of Topological Psychology

9 Cascade of Causal Influences Barkin, S., & Schlundt, D. (2011). The Challenge Facing Translation of Basic Science into Clinical and Community Settings to Improve Health Outcomes. Environ Health Perspect, 119(10). Complex Systems Science Reductionist Science Environment Antecedents Biobehavioral Self Past Present Future Self Causal Nexus Cascade of Causal Influences Consequences

10 Hypothesis: Obesity epidemic represents a mismatch between individual and environment We evolved as hunters, gatherers, and scavengers in an environment of food scarcity and high physical activity demands Food systems have since evolved Food is a profit driven industry designed to entice individuals to eat Food processing creates unprecedented taste and energy density Approaching the point where half of US food is purchased and consumed away from home Transportation and work systems have evolved Machines and electronics have increased work productivity and decreased physical demands Transportation is largely door-to-door by automobile

11 Technologies/Methods to study personenvironment transactions Geographic information systems (GIS) Computer mapping software Example: Nashville food deserts Global positioning systems (GPS) Capture location, speed, and trajectory of movement through environments Example: Personal resource mapping Ecological momentary assessment (EMA) Real-time capture of cognition, emotion, and behavior Example: Food transaction tracking

12 Nashville Food Deserts for CPPW GIS layers Parcels with utilization codes to identify residences and stores Bus routes, bus stops Census data from (factor analytically derived indicators of people and housing) Health outcomes (obesity, hypertension, diabetes, cholesterol, uninsured) from REACH 2010 Variables at the parcel, census tract, block group, and block level. Larson, C., Haushalter, A., Buck, T., Campbell, D., Henderson, T., & Schlundt, D. (2013). Development of a Community-Sensitive Strategy to Increase Availability of Fresh Fruits and Vegetables in Nashville s Urban Food Deserts, Preventing Chronic Disease, 10.

13 Method Started with residential parcels Computed distance from each residence to Nearest major grocery store (e.g., Kroger, Public, Walmart) Nearest bus stop 31 other variables measuring environment and health Normalized each variable by creating z-scores For each parcel, calculated a weighted sum of z-scores Aggregated data over residential parcels within census block Scores ranged from -37 to +60 for 460 census blocks that had residential properties Used a cutoff score of 20 or higher to define food deserts

14 Using criteria of 20 or greater, the four food deserts in Nashville were easily located

15 Food desert impact areas are in red and orange

16 GIS is a cool tool Provides data to describe the environment Many sources of data to capture Built environment Transportation Food resources Social determinants of health Tremendous tool for the environment side of the personenvironment equation

17 Personal Resource Mapping using GPS Gathered data on individual s personal geography Combine that with existing GIS data to create personal resource maps Use portable GPS monitor that can be carried in pocket, backpack or purse

18 3 individuals including myself wore a QSTARZ Travel Recorder for 7-14 days each The Travel Recorder captured latitude and longitude, travel speed, & elevation every 5 seconds Uploaded into ArcGIS from an excel spread sheet Methods

19 Metro Parcel Data Layer Shows each property and its type of use. This map shows Wilson hall and adjacent properties. All 3 of us visited Wilson hall. Comparing the GPS to the property layer we can tell what kind of businesses each person visited

20 Nic stayed on campus and rode to Wal-Mart and Target Dr. Schlundt lives in Ashland City and visited a friend in Goodlettsville Dr. Novak lives in Brentwood and basically went to and from work

21 This graph shows each of the 3 people accessed food resources Dr. Novak went shopping the least and Dr. Schlundt shopped the most Dr. Novak visited fast-food resources the most

22 Dr. Novak stayed still the most Dr. Schlundt drives the fastest

23 By geocoding addresses and tracking movement through time and space, we can begin to understand how people interact with different environmental systems Social interpersonal Networks resources and barriers Economic and financial Resources and barriers Health needs Physical and Built Environment resources and barriers Food and nutritional resources and barriers Health behaviors and outcomes Information tools and sources resources and barriers Psychosocial needs Transportation resources and barriers Cognitive and perceptual resources and barriers Cultural communities resources and barriers

24 Ecological Momentary Assessment Capturing events as they occur Data collection is moved to the natural environment Three major strategies Event based recording Cued or prompted recording Continuous monitoring Becoming very possible with smart-phones and other gadgets (Fitbit and Garmin Fenix to right)

25 Phone App to monitor food transactions HTML 5 web site with google maps Captures latitude and longitude Asks series of questions Uploads data to server

26 From study of mother-toddler feeding. Moms used app for a week Place type EatHere FoodGroups Time Date Transpo rt People Latitude Longitude Baja burrito :41:26 PM 11-May Edley's barbecue :32:22 PM 12-May Las Paletas :52:49 PM 13-May Trader joe's :21:26 PM 13-May Bombay palace :54:17 PM 13-May Vanderbilt courtyard cafe :56:44 AM 15-May th south farmers market :47:04 PM 15-May Eskind :12:09 PM 18-May We learned that we needed to include husbands/partners to understand where the food in the family comes from. One week is not long enough to understand how people use their food environments

27 The Challenge Is obesity a disease, an individual clinical problem, a failure of selfregulation, a metabolic disorder? Is obesity a failure to adapt in healthy ways to complex interpersonal, food, transportation, political, social, cultural, and economic environments? Can we use technology to gather data on person-environment transactions to improve treatment and prevention? Use cell phones to passively capture latitude and longitude data over weeks or months Geocode the individual's home and work address and locate these on personal resource maps Use geospatial algorithms to extract individual level data that will assist in treatment planning, monitoring, and implementation Aggregate person-environment transaction data to help plan and evaluate public health interventions By seeing obesity as the outcome of person-environment transactions, we are more open to the possibility of multi-level interventions for treatment and prevention