Multilevel analysis of the impact of neighborhood environment on postpartum depressive symptoms.

Background: About one in ten mothers experience postpartum depression (PPD) in Japan. Although the individual and social risk factors of depression have been reported, few studies have focused on the neighborhood environmental features. In this study, we examined the association between neighborhood environmental features and PPD symptoms among Japanese women.

Methods: Questionnaire survey including women who participated in 3- or 4-month health checkup in Nagoya City, Japan in 2012 was used. PPD symptoms were evaluated using Edinburgh Postnatal Depression Scale (EPDS). As the neighborhood places where postpartum mothers often visit, we measured availability of grocery stores, community centers and asobiba (playground for children) within residential neighborhood unit using geographic information system. A multilevel analysis was conducted on 2,298 individuals nested within 388 school districts using Stata 15.1 software.

Results: Mothers who live in the neighborhood with more number of asobiba had lower EPDS score, even after adjustment for individual factors (B: -0.12, 95%CI: -0.24, -0.01), and additional adjustment for other neighborhood environmental factors (B: -0.14, 95%CI: -0.27, -0.02).

Limitation: Our cross-sectional design limits to draw causal inferences. As for the evaluation of PPD symptoms, no diagnosis has been made. Moreover, we do not have the information on the accessibility to transportation, and the exact residential location of the survey respondents.

Conclusion: Our findings suggest that the availability of asobiba in the community has a protective effect on PPD symptoms. Providing more asobiba in the neighborhood for new mothers may be a viable preventive strategy for PPD symptoms.