Summary Report: The Impacts of Flooding Events on Mental Health in New Brunswick


Flooding events are among the most devasting natural disasters – and as a result of climate change, natural disasters such as flooding are expected to occur more frequently and be more severe. The effects caused by flooding can create a lot of stress and uncertainty. Previous research studies consistently demonstrate negative mental health impacts associated with flooding, such as anxiety, depression, and post-traumatic stress disorder (PTSD) and increases in need for health services. However, the research in this area is limited by lower quality research methodology, including self-selected samples and uncontrolled statistical analyses. The research study presented in this report describes mental health impacts of flooding. In doing so, it fills an important knowledge gap, as it is among the few studies to use population-based sampling and multivariable regression models in estimating the impacts of flooding and to identify high-risk population sub-groups that are more vulnerable to the impacts of flooding. The specific objectives of this research are to: 1. Characterize populations affected by flooding in the province of New Brunswick. 2. Determine which mental health outcomes are negatively affected by flooding. 3. Identify high-risk population sub-groups that may be more vulnerable to the mental health impacts of flooding. A population-based longitudinal cohort study design was established using linked, pseudonymized person-level administrative data available for access through the New Brunswick Institute for Research, Data and Training (NB-IRDT). Seven significant flooding events in New Brunswick were examined: 2005, 2008, 2012, 2014, 2015, 2018, and 2019. Cohort members were defined as exposed if they lived in a geographic area identified to have any flooding based on a combination of flood-related data from the Government of Canada and the Government of New Brunswick. Six mental health outcomes and six alternate outcomes were compared between exposed and unexposed populations. Mental health outcomes include health service use for mental illness and more specifically for mood and/or anxiety disorders, hospitalization for mental illness-related reasons and for post-traumatic stress disorder (PTSD), and physician services for counselling/psychotherapy, as well as death by suicide. Several alternate outcomes were also examined to provide a fuller understanding of the experiences of the exposed population, including Emergency Department use, hospital service use, school attendance in children, and withdrawal from post-secondary education in youth. Risk factors for mental health and alternate outcomes were also considered in exposed populations, including flood-related, sociodemographic, and health-related characteristics. Advanced regression modeling techniques were used to compare outcomes during the same time period in an exposed population relative to an unexposed population that was similar with respect to age, sex, socioeconomic status, and pre-flooding mental health.