DIABETES JOURNAL CLUB NOVEMBER 17, 2011 Margaux Añel-Tiangco, MD

Background  Observational studies have shown that neighborhood attributes like poverty and racial segregation are associated with increased risks of obesity and diabetes

How neighborhoods might affect health  Changes in built environment  Grocery stores  Spaces where residents can exercise  Proximity to health care providers  Neighborhood safety might affect  Exercise level  Diet  Level of stress  Social norms might affect health-related behaviors

Methods  Moving to Opportunity (MTO)  Project of the Dept of Housing and Urban Development  5 cities: Baltimore, Boston, Chicago, LA, New York Eligibility: Families with children younger than 18 y/o who live in selected public housing developments in census tracts with poverty rates ≥40% in 1990 Families were given vouchers from Outcomes data collected from one woman from each family (usually the household head) from (~10 yrs after randomization)

Interventions  Low-poverty voucher  Given rent-subsidy voucher - required to use in a low poverty rate census tract (<10% poverty rate)  Received short-term counseling for housing search  After 1 year, can move to a different tract regardless of poverty rate in that tract  Traditional voucher group  Given rent-subsidy voucher with no restrictions on where to live; no housing counseling  Control group – not given voucher

Results 48% used voucher63% used voucher

Baseline characteristics

Census-Tract Poverty Rate According to Study Group median 50% 33% 28%

 13%  19%  22% No difference p = 0.05

Why is there a difference in health outcomes?  Testing for nonlinear relationships between neighborhood attributes and health outcomes had low statistical power

Census tract characteristics

Study critiques  Only half of participants used the vouchers and many of the families in the control moved to lower poverty areas  Participants volunteered – Hawthorne effect

Take home points  Moving to a neighborhood with a low poverty rate is associated with improvements in BMI and A1c  Mechanisms remain unclear  Further research needed to look into clinical or public health interventions that ameliorate the effects of neighborhood environment on obesity and diabetes

Questions?