Abstract B25: Impact of neighborhood obesogenic factors on obesity in over 100,000 participants of the Multiethnic Cohort Study
Authors: Cheng Iona , Yang Juan , Hertz Andrew , Clarke Christina , Albright Cheryl , Marchand Loic Le , Kolonel Laurence , Henderson Brian , Monroe Kristine , Lin-Gomez Scarlett , Wilkens Lynne 
Published: October 2015

Introduction: The obesity epidemic is a serious health priority with important consequences on obesity-associated cancers. Socioeconomic (SES) and “obesogenic” attributes of neighborhoods may promote obesity by providing a context where it is difficult to engage in physical activity and/or access healthy foods. This may be particularly relevant for minority populations that have limited neighborhood resources and experience higher levels of obesity. However, the extent to which these neighborhood factors translate into individual levels of body mass index (BMI) have been mixed among racial/ethnic groups. Therefore, leveraging the scale and racial/ethnic diversity of the Multiethnic Cohort (MEC) study, we examined the associations between neighborhood obesogenic factors and BMI among African Americans, Japanese Americans, Latinos, and Whites in California.

Methods: Study subjects included 107,697 MEC participants, ages 45-75, residing in California (93% from Los Angeles County) with geocoded addresses and data available on BMI at baseline questionnaire (1993-1996). Residential baseline addresses were geocoded to latitude and longitude coordinates and assigned to 1990 Census block groups to ascertain neighborhood levels of SES, population density, and commute patterns. In addition, geocodes were linked to business data to quantify neighborhood attributes of the retail/restaurant food environment, parks, recreational facilities, walkability, traffic density, and total businesses within a residential buffer area of one mile in radius. Polytomous logistic regression was conducted to examine the relationship between the obesogenic environment and BMI in kg/m2 (underweight: BMI&lt;18.5; normal weight: BMI=18.5-&lt;25 (reference); overweight BMI=25-&lt;30; obese BMI&gt;30) adjusting for age, sex, and race/ethnicity and including all neighborhood obesogenic factors. Stratified analyses were conducted by gender and race/ethnicity.

Results: Lower neighborhood SES was significantly associated with higher odds of being overweight and obese. For males, in comparison to the highest SES quintile (Q5), the odds ratios and 95% confidence intervals for obesity with decreasing SES quintiles were Q4: OR=1.36 (95% CI: 1.20-1.50), Q3: OR=1.59; (95% CI: 1.40-1.81), Q2: OR=1.70 (95% CI: 1.49-1.93), and Q1: OR=1.89 (95% CI: 1.63-2.19). For females, similar patterns of associations were seen although larger associations were observed (Q4: OR=1.52 (95% CI: 1.36-1.70), Q3: OR=2.11 (95% CI: 1.89-2.34), Q2: OR=2.72 (95% CI: 2.43-3.03), Q1: OR=3.34 (95% CI: 2.94-3.78)). All racial/ethnic groups demonstrated similar patterns of associations between SES and obesity. Neighborhoods with smaller density of businesses (i.e. fewer nearby walkable destinations) were significantly associated with higher odds of obesity (ORQ1 vs. Q5=1.24; 95% CI: 1.14-1.34). This association was consistently observed among African American males and females, U.S. born Latino males, foreign-born Latino females, and White females. For White males and females, residence in neighborhoods with lower levels of commuting by car or motorcycle were associated with lower odds of obesity in comparison to residence in neighborhoods at the highest level of commuting by car or motorcycle (males ORQ1 vs. Q5=0.51; 95% CI: 0.35-0.76; females ORQ1 vs. Q5=0.64; 95% CI: 0.48-0.84).

Conclusion: These findings demonstrate the impact of the neighborhood environment on obesity with complex relationships observed across gender and racial/ethnic groups. Future analyses will incorporate individual-level health behaviors such as dietary factors, physical activity and smoking, as well estimates of genetic ancestry. Our understanding of this relationship between the obesogenic environment and obesity provides a framework for future studies of neighborhood obesogenic factors and cancer risk.

Citation Format: Iona Cheng, Juan Yang, Andrew Hertz, Christina Clarke, Cheryl Albright, Loic Le Marchand, Laurence Kolonel, Brian Henderson, Kristine Monroe, Scarlett Lin-Gomez, Lynne Wilkens. Impact of neighborhood obesogenic factors on obesity in over 100,000 participants of the Multiethnic Cohort Study. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B25.