Abstract: A Nationwide Panel Study on Green Environment and Incident Depression in South Africa: Sustainable Development Implications for Mental Health in Resource-Limited Settings (Society for Social Work and Research 22nd Annual Conference - Achieving Equal Opportunity, Equity, and Justice)

Schedule:

Saturday, January 13, 2018: 9:45 AM

Liberty BR Salon I (ML 4) (Marriott Marquis Washington DC)

* noted as presenting author

Andrew Tomita, Ph.D., Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa

Alain M. Vandormael, Ph.D., Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa

Diego Cuadros, Ph.D., Department of Geography, University of Cincinnati, Cincinnati, OH

Enrico Di Minin, Ph.D., Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland

Vuokko Heikinheimo, Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland

Frank Tanser, Ph.D., School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa

Rob Slotow, Ph.D., School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa

Jonathan K. Burns, Ph.D., Institute for Health Research, University of Exeter, Exeter, United Kingdom

Background and Purpose: Unparalleled levels of urbanization and economic industrialization are changing the way individuals associate with the natural environment in developing countries. Although studies suggest the mental health benefits of green living environment, the evidence to this theory has been inconsistent. Furthermore, there are few evidence-based large-scale population studies that apply to sub-Saharan African settings. This study explored the relationship between exposure to green space environments and incident depression in South Africa.

Methods: Panel data (waves 1-3) from the South African National Income Dynamics Study (SA-NIDS) was used. The primary outcome, depressive symptomatology, was assessed using a 10-item version of the Center for Epidemiologic Studies Depression Scale (CES-D). The main covariate of the study was green living environment, operationalized from a satellite-derived normalized difference vegetation index (NDVI). Each participant was assigned a NDVI value based on the GPS co-ordinates of their household location. Mixed-effects logistic regression models were fitted to examine the link between NDVI and depression.

Results: Approximately one-fifth (20.9%) of the study cohort (N=11,156), initially case free at baseline, had significant depressive symptomatology (CES-D score≥10) during follow-up. Higher NDVI (greener living environment) demonstrated significantly lower odds of incident depression among middle-income Africans based on mixed-effects logistic regression models (aOR=0.98, 95% CI: 0.97-0.99).

Conclusions and Implications: Apparent trade-offs between economic development and environmental protection have long been debated within developing countries. Although the benefit of economic well-being and poverty alleviation are recognized, our results highlight the importance of green environment for mental health, reaffirming the need for social justice through environmental protection and biodiversity conservation as part of integrated sustainable development strategies in resource-limited countries.