Health predictors of neighborhood selection: a prospective cohort study of residential mobility in Ontario, Canada.

Background: Health selection into neighborhoods describes unhealthy people moving disproportionately to lower-income neighborhoods, producing observable socioeconomic gradients sometimes falsely attributed to neighborhood effects on health. We investigated residential mobility outcomes and their relationship to baseline health using population-level data linkages in Ontario, Canada.

Methods: We included Canadian Community Health Survey (CCHS) respondents ages 25 to 64 between 2005 and 2014 (n=93,235). We assessed baseline health using self-reported health and multimorbidity. We captured moves using health administrative data and the Canadian census. We fit multinomial logistic regression models with a six-category residential mobility outcome: (1) non-movers in low-income neighborhoods; (2) non-movers in high-income neighborhoods; (3) movers from low-income to low-income; (4) movers from low-income to high-income; (5) movers from high-income to low-income; and (6) movers from high-income to high-income. We adjusted models for CCHS cycle, age, sex, household income, immigrant status, and residential instability.

Results: Compared to those with very good or excellent health, respondents reporting fair or poor health at baseline had higher odds of moving from low- to low-income neighborhoods (aOR=1.73, 95%CI 1.46-2.05), moving from high- to low-income (aOR=1.64, 95%CI 1.35-1.98), moving from low- to high-income (aOR=1.26, 95%CI 1.04-1.54), and not moving within low-income (aOR=1.36, 1.23-1.51) relative to not moving within high-income. Results were consistent for objective health measures, comparing respondents with at least four chronic conditions to those with one or none.

Conclusions: In a large, population-based study, both subjective and objective measures of health had a strong relationship with residential mobility outcomes.