Neighborhood and individual socioeconomic determinants of hospitalization.

BACKGROUND: A number of studies have established links between neighborhood social environments and health. In a previous study of 8197 adults, death rates for adults with low socioeconomic status (SES) were highest in high-SES neighborhoods, lower in moderate-SES neighborhoods and lowest in low-SES neighborhoods. This study examines whether these findings extend to time to hospitalization.

METHODS: Population-based study of 1686 women and men, aged 25 to 74 at baseline, from 82 neighborhoods in four California cities. Participants were surveyed and medically examined in 1989-1990 and followed through the end of 2002. Neighborhood-level SES was defined by five census variables and divided into three levels. Individual-level SES was defined by household income and educational level and divided into tertiles (nine individual/neighborhood SES groups).

RESULTS: There were 627 hospitalizations. The age- and gender-adjusted rates of any hospitalization between 1989-1990 and the end of 2002 for adults with low SES were highest for those living in high-SES neighborhoods (51% compared with 28% to 38% for adults from the other eight individual/neighborhood groups). For these adults, time to hospitalization, as indicated by survival curves, was significantly shorter compared with the other individual/neighborhood groups (p < 0.01, multilevel Cox proportional hazards model). Findings were not explained by baseline differences in individual-level sociodemographic characteristics, health behaviors or risk factors, health status, or proximity to neighborhood goods and services.

CONCLUSIONS: These findings suggest that factors leading to increased mortality for adults with low SES in high-SES neighborhoods also affect hospitalization.