Are neighborhood health associations causal? A 10-year prospective cohort study with repeated measurements.

People who live in disadvantaged neighborhoods tend to have poor physical and mental health, but this might be due to selective residential mobility rather than causal neighborhood effects. As a test of social causation, I examined whether persons were less healthy when they were living in disadvantaged neighborhoods than at other times when they were living in more advantaged neighborhoods. Data were taken from the 10-year Household, Income and Labour Dynamics in Australia (HILDA) prospective cohort study, which had annual follow-up waves between 2001 and 2010 (n = 112,503 person-observations from 20,012 persons). Neighborhood disadvantage was associated with poorer self-rated health, mental health, and physical functioning, higher probability of smoking, and less frequent physical activity. However, these associations were almost completely due to between-person differences; the associations were not replicated in within-person analyses that compared the same persons living in different neighborhoods over time. Results were similar when using neighborhood remoteness as the exposure and when focusing only on long-term residence. In contrast, poor health predicted selective residential mobility to less advantaged neighborhoods, which provided evidence of social selection. These findings provide little support for social causation in neighborhood health associations and suggest that correlations between neighborhoods and health may develop via selective residential mobility.