Household Crowding and Mental Health: The Importance of Exposure Duration

The present longitudinal study on residential density, interpersonal processes, and psychological health illustrates the importance of exposure duration in environment-health research. With longer exposure to residential density, individuals reported higher levels of psychological symptoms, lower perceived social support, and a greater tendency to socially withdraw. More importantly, the processes linking density to psychological health changed over time. After 2 months of living together, density had negative effects on the psychological health of residents with average or low levels of perceived social support; it had little impact on residents with high levels of perceived social support. In addition, residential density was associated with greater social withdrawal which, in turn, was negatively associated with psychological health. However, 6 months later, residential density appeared to alter directly interpersonal relationships in the household such that the people became increasingly withdrawn and perceived their house mates to be relatively un-supportive. These changes in interpersonal relations and perceptions of social support seemed to account for the increasing negative effect of density on psychological health over time.