Lancet Planetary Health 1, e134–e141 (2017)

Experiencing natural disasters such as flooding has been linked to adverse mental-health outcomes. Because climate change is likely to increase the incidence of river, groundwater, and coastal flooding, understanding the risk factors that mediate the relationship between flood experiences and mental health can inform projections of climate-change health impacts.

Alice Munro from the London School of Hygiene and Tropical Medicine, UK, and colleagues, analysed survey data from residents of UK counties affected by flooding. One year after flooding, the prevalence of anxiety, depression, and post-traumatic stress disorder symptoms was higher in those who were displaced by flooding compared to those who were flooded but not displaced, after controlling for severity of flooding. Those who were displaced were more likely to report symptoms of depression and post-traumatic stress disorder if they received no advanced warning versus at least a 12-hour notice prior to flooding and displacement. Duration of displacement had no effect on mental-health outcomes. These results suggest that early warning systems or services that reduce the need for evacuation could protect against mental-health disorders following floods.