Abstract

Examining the relationship between drought and mental health outcomes of depression and anxiety in the U.S.

By

Robyn J. Cathey

December 4, 2017

BACKGROUND: Drought is likely linked to depression and anxiety through environmental and economic factors. Having a better understanding of this relationship would assist public health officials and policy-makers in future drought preparedness and mitigation strategies.

METHODS: Depression and anxiety data were collected for 36 states from HCUPnet, an online system of hospital inpatient and emergency department information. Drought data were collected from the U.S. Drought Monitor, a weekly monitor integrating multiple drought indices to produce a single index, for 2011-2014. Proportions were calculated for state hospital mental health discharges from total state hospital discharges. Annual state drought data was dichotomized based on a 30% areal drought threshold for drought exposure conditions. Repeated measures ANOVA was used for analysis of the relationship between states’ depression and anxiety discharges and states’ drought exposure.

RESULTS: The effect of time on depression was significantly different for states in the exposed and unexposed condition, F (3, 32) = 4.22, p = 0.01. The effect of time on anxiety was not different for states in the exposed and unexposed drought conditions, F (3, 32) = 1.92, p = 0.15. Post-hoc comparisons using four paired samples t-tests indicated a significant effect of drought exposure on depression comparing exposed drought condition with unexposed drought condition during 2011, 2012, 2013 and 2014. A significant effect of drought exposure condition on anxiety comparing exposed drought condition with unexposed drought condition during 2011, 2012, 2013 and 2014.

CONCLUSION: Depression and anxiety discharges differed over time and between states in the exposed and unexposed drought conditions from 2011-2014. Depression and anxiety discharges were higher for states in the unexposed drought condition. Further research would refine the examination of this relationship.