The environments, mobility/transportation, and health

Sensors

GSM tower

COMPONENT 1: Improvement of wearable device, real-time transmission

End users

Acquisition server

COMPONENT 3: Web applications, prompted recall, counseling

COMPONENT 2: Data processing, GPS algorithms, Accelerometer algorithms

Outputs /

Applications

Algorithms

GIS

Web server

Contextual expology

= a subdicipline interested in contextual exposure

assessment

The environments,

mobility / transportation,

and health

= identification

of the places

and times of

exposure

(the where

and when of

exposure)

Erasmus Medical Centre

Rotterdam

March 22 2013

Basile Chaix, INSERM

Environmental exposure assessment in the RECORD Study

Chronic environmental exposures

Electronic survey of regular mobility

Global Positioning System tracking

Acute environmental exposures

Regular mobility assessment

VERITAS in RECORD:

Chaix et Kestens.

Am J Prev Med 2012

a succession of 27 screens with standard questions and interactive maps

Chaix et al. RECORD Study.

Int J Epidemiol 2012

Introduction

Participants are asked to

draw the delimitations of their perceived residential neighborhood

Geocoding of activity places

- residences

- workplaces

- supermarkets,

outdoor markets, bakeries,

butcher shops,

fruit and vegetable shops,

fish stores, cheese merchants,

specialized food stores

- tobacco shops,

- bank, post offices

- hairdressers

- transportation stations

- sport facilities

- entertainment facilities

- places for regular cultural,

community or spiritual activities

- places to which relatives are

taken and places where people

are visited

"The loss of close collaboration between urban planning and public health professionals that characterized the post-World War II era has limited the design of effective interventions that might translate into improved health for urban populations"

Availability of Google Maps search functionalities to retrieve places and services

Mary Northridge, J Urban Health 2003;80:556-568.

Urban planning

Public health

Findings from geo-ethnography

Low socioeconomic subgroups...:

Tooltips allow one to provide information on each service (visit frequency, etc.)

Matthews S. Am J Prev Med 2008;34:257-259.

... trapped in a low resource environment?

... travelling across low resource environments?

• Boston, 10 families, use of 222 locations

Regular activity space

Land use planning

Epidemiology

Air pollution studies

• 6% in the residential census tract
• 21% in immediately adjacent census tracts
• 73% elsewhere across the city

Standard deviational ellipse

Innovative directions for research

New Urbanism

(Matthews, Am J Prev Med 2008)

Urban health

• Spatial polygamy

-> collect extra-residential information

• Activity space
• Network of usual places

Barriers in mobility and related spatial isolation as a source of social disadvantage

(Schönfelder, Transport Policy 2003)

Spatial behavior

(Flamm M, Kaufmann V)

Preston et al. J Transport Geography 2007;15(3):151-160.

Neighborhood

and health studies

A static view of environmental exposures

Review on n'hoods and metabolic factors (131 articles)

• 90% of studies focused on residential neighborhoods
• 6% focused on non-residential environments
• 4% accounted for both environments

(Leal & Chaix, Obesity Reviews 2011)

"Local trap": a literature focused on the local environment

(Cummins, Int J Epidemiol 2007)

"Residential trap": a literature focused on the residential neighborhood

(Chaix, Annu Rev Pub Health 2009)

Socioeconomic position

Residential environment

Neighborhood & health DYAD

Neighborhood, mobility & health TRIAD

At least two reasons to incorporate mobility in N&H research:

- High white-collar workers (2008):

Transportation habits

• residences and workplaces in urban centers

regular use of public transport

Second wave of the RECORD Study (ongoing)

Neighborhood and health (N&H) studies

- Blue collar workers (2008):

- 4540 participants surveyed (March 21 2013)

- 65180 regular activity places geocoded

• lack of access to public transport from residences / workplaces

higher dependence on cars

National Survey on Transport and Travel

Current N&H studies

Early N&H studies

Chaix & Kestens

Am J Prev Med 2012

- Changes in the use of cycling between 1994 and 2008:

• increase among high-white collar workers
• decrease among blue-collar workers

2010-2012

1985

1990-1995

2002-2003

Social disparities in transportation mode use likely result in socio-spatial disparities in physical activity

N'hood socio-economic status

Multilevel analysis

Built and service environment

Incorporation of mobility

Social processes

Social epidemiology

Social sciences

Urban planning

Geography

Environ. psychology

Social epidemiology

The RECORD Cohort Study

Summary of findings of RECORD wave 1

Chaix et al. Hypertension, 2010. 55(3): p. 769-775.

Chaix et al. Epidemiology, 2011. 22(1): p. 18-26.

Association between neighborhood socioeconomic status and blood pressure. Mediating role of excess weight and fat.

Neighborhood influences on participation in the study.

Correction of neighborhood effects on type 2 diabetes from bias.

- Wave 1 : 2007 - 2008

N = 7290 participants

- Wave 2 : 2011 - 2013

N = 8600 (additional inclusions)

- 30-79 year old in 2007 - 2008

- 111 municipalities of the Paris

region and 10 districts of Paris

Van Hulst & Chaix. J Hypertens, 2012. 30(7): p. 1336-46.

Leal & Chaix. Epidemiology, 2011. 22(5): p. 694-703.

A typology of neighborhoods was associated with blood pressure, even after adjustment for NSES and risk factors. Different patterns reported for systolic & diastolic blood pressure.

Associations between neighborhood socioeeconomic status and body mass index or waist circumference. Separability of these associations from those with individual socioeconomic status?

Chaix et al. Soc Sci Med, 2011. 73(10): p. 1543-1550.

Leal & Chaix. Am J Epidemiol, 2012. 175(11): p. 1152-1162.

- Wave 1 and wave 2:

Association between neighborhood socioeconomic status and resting heart rate. Mediating role of physical activity and excess weight and fat.

Physical and service environments as predictors of body mass index and waist circumference. Application of other matching techniques to assess whether the associations are separable.

- Medical, clinical, biological checkup

- Socioeconomic questionnaire

- Behavioral questionnaire

- Psychological questionnaire

- Questionnaire on the neighborhood

Karusisi & Chaix. Prev Med, 2012. 55(1): p. 50-55.

Chaix et al. PLoS One, 2012. 7(3): p. e32908.

The presence/quality of green/open spaces was associated with jogging and with jogging inside rather than outside one's neighborhood. Additional supportive effect of social cohesion.

Within-supermarket correlation in body mass index and waist circumference. Shopping in a hard-discount, especially among low educated individuals, is associated with excess weight and fat.

- Wave 2 :

VERITAS electronic survey of regular destinations

Challenges in the definition of mobility-based measures of exposure

Measuring exposure to contexts with regular mobility data

Chaix et al. RECORD Study. Int J Epidemiol 2012

Selective daily mobility bias:

Confounding due to factors that determine both places of daily mobility and health or health behavior

+ estimated shortest paths between locations

Exposure areas around activity places

Exclusion of activity places

related to the outcome

Both with destination surveys and GPS tracking, it is critical to collect information on the activities practiced at the different places for filtering of exposure measures.

Chaix & Kestens.

Am J Prev Med 2012

Measurement in GPS-based "daily path areas"

Zenk, Health Place 2011;17:1150-1161.

• Exposure area: 0.5 mile around all GPS points

• A high density of fast-foods was associated with:
• a higher intake of saturated fat
• a lower intake of whole grains

• A high density of fast-foods was associated with:
• a higher intake of saturated fat
• a lower intake of fruits/veggies
• a lower intake of whole grains

... when measured in the daily

path area

... but not when measured in the

residential neighborhood

Selective daily mobility

Chaix, Health Place 2013;21C:46-51.

Selective daily mobility

HOME

Transportation habits: contributing to environmental effects on health?

Transportation and health

as an emerging field

Studies of mobility based on GPS tracking

Neighborhood determinants of walking for transport, RECORD Study

Transportation and health

Ecological data

Limitations of current literature

Public health / Nutrition studies

Transportation studies

Bassett et al.

J Phys Act Health. 2008

• GPS tracking and mobility survey (often over one day)
• ... but without reliable information on physical activity and health

• GPS tracking and accelerometry
• ... but lack of information on activity places and transportation modes

Adjusted for age, sex, marital status, education, employment status, occupation, income, dwelling property

Integrate the Public health / Nutrition approach and the Transportation approach to GPS studies

Chaix et al. Health Place. 2013;21C:46-51.

RECORD GPS Study

...as an alliance between...

Transportation authorities/operators

Public health

Transportation and health:

Individual longitudinal data

Free bus pass for people >60y in England in 2006

• INPES
• IReSP
• ARS of Ile-de-France

• Ministry of transportation
• CERTU
• STIF
• RATP
• IdF Regional Council

• Associated with an increased use of public transport
• Older participants using public transport had a decreased risk of becoming obese between 2004 and 2008

(JECH 2012;66:176-180)

Light rail transit system (LRT) installed in North Carolina

• Nearby residents using the LRT had an average -1.18 reduction in BMI and an 81% reduced odds of becoming obese between 2006 and 2008

(Am J Prev Med 2010;39:105-112)

Use of motorized transportation over 1997-2006 (China)

• Use of motorized transportation for >5y was related to a 1.2 kg greater weight gain

(Am J Prev Med 2012;43:1-10)

Annual km traveled by motor vehicles (over 6.4y, Spain)

RECORD GPS Study

• Among those with unchanged exposure, those in the highest category of distance traveled had a greater risk of becoming overweight/obese (HR = 1.4)

(Am J Prev Med 2013;44:254-259)

• After the second wave of the RECORD Study
• GPS and accelerometer at the belt for 7 days
• Participants report information on their activity places in a diary
• Device sent back by mail

Transportation and health

Reviews and meta-analyses

Wanner et al. Am J Prev Med 2012;42(5):493-502

• March 21 2013: recruitment

of 210 participants

Of 30 studies, 25 reported associations for all, most, or some variables in the expected direction: more active transport (walking, cycling) associated with lower body weight

Hamer et al. Prev Med 2008;46(1):9-13

Walking or biking to work was associated with a decreased cardiovascular risk, especially among women (hypertension, stroke, myocardial infarction, coronary heart disease mortality)

Rissel et al. Int J Environ Res Public Health 2012;9:2454-78

The use of public transports was associated with a 8 to 33 mn longer time of walking per day.

Algorithm for the automatic processing of GPS data

- Cleaning of GPS data (based on signal

quality, etc.)

- Interpolation of missing data

- Detection of activity places

- Segmentation of the trajectory into

activity places and trips between them

- Detection of transportation modes

- Empirical tests to validate and

calibrate the algorithm

Mobility Web Mapping application

(for the RECORD GPS Study)

• Survey of activities, visit frequencies, and transportation modes over 7 days
• Delete fictive activity places
• Report unobserved or unidentified activity places
• Identification of activity places also in VERITAS
• Aim: use of the application in near-real time with over-the-air data transmission

FINAL OUTPUTS

1. Timetable with

activity places

and trips

2. Corrected

geographic file

of the trajectory

STUDY OUTPUTS

...integrating:

• cleaned GPS data (activity places, trips)
• corrections and additions from the survey
• attribute data (activity type, etc.)

3. Aggregation of accelerometry according to

the 7-day timetable

Concluding remarks

DESCRIPTIVE DATA ON TRIPS

PRELIMINARY DESCRIPTIVE DATA

Analyses at the trip level (n = 4186)

(n = 60)

• Important to strengthen the partnership between Public health and Urban planning among:

4186 trips for 132 participants (med.: 30 / indiv.)

Outcome variable: use of the train in the trip

Proportion of trips by walking according to the calculated distance (n = 132, 4186 trips)

• 32% of the overall energy expenditure over 7 days related to transport

(Freedson VM3, 2011)

Time (departure)

Day (departure)

- researchers & research administrators

- decision makers

- field workers

Week 75%

Week-end 25%

Morning (6h-10h) 17%

Day (10h-17h) 53%

Evening (17h-22h) 27%

Night (22h-6h) 3%

• Compared to trips including a travel by car, trips including a travel with public transport imply:

• Important to account for daily mobility in health research

Distance (calculated)

Mode (when unique)

• 1586 additionals footsteps
• a 88.8 kcal higher energy expenditure

...or respectively

• 216 additional steps for each 10 mn of trip
• 11.1 kcal for each 10 mn of trip

- identification of population with specific needs

- active/motorized transportation and its health effects

- improved exposure assessment

< 500 m 23%

500 m–1000 m 16%

1000 m–2500 m 19%

2500 m–5000 m 13%

5000 m–10000 m 12%

> 10000 m 17%

Walk 46%

Bike 2%

Car 42%

Metro 6%

Bus 2%

Train 2%

• Complementary strategies to incorporate daily mobility in health research, including:

- electronic surveys of regular destinations to assess chronic

environmental exposures

- GPS tracking to assess acute environmental exposures