The present study aimed to evaluate the long-term psychological effects of the 2011 flood in Thailand on flood victims and unaffected residents, taking into account risk factors such as floodwater levels in the house, period of flooding, and disruption to essential services.

Surveys were conducted in Salaya and Nakhon Chaisri subdistrict, Nakhonpatom Province, from May to June 2012. Approximately 400 households were selected. Measures of sociodemographic variables, exposure to flooding, incidents (eg, disruption of services), and outcome variables (Kessler 10) were recorded.

A total of 407 respondents completed the survey. The results of the univariate analysis showed that possible serious mental illness was approximately 1.5 times higher in flood victims than in unaffected respondents. After adjustment for potential confounding factors, significant associations were found for disruption of essential services and hypertension or diabetes with possible serious mental illness.

Disruption of essential services and chronic illness may affect psychological distress among flood victims. Public health agencies should develop and evaluate strategies to improve risk communication and psychological support for flood victims. (Disaster Med Public Health Preparedness. 2017;11:300–304).