BOSTON — The estimated prevalence of serious mental illness among Hurricane Katrina survivors doubled in the months after the disaster. But suicidal ideation among this population decreased significantly during that period, compared with several years ago, a new study has shown.
The jump in mental illness post-Katrina could be predicted, but the decrease in the prevalence of suicidal thoughts among those with serious mental illness “was a surprise,” lead author Robert C. Kessler, Ph.D., said in a teleconference announcing the findings of the first Hurricane Katrina Community Advisory Group survey.
Through questions designed to assess several dimensions of personal growth resulting from the trauma of the hurricane, Dr. Kessler and his colleagues at Harvard Medical School, Boston, determined that the lower conditional prevalence of suicidality was a function of individuals' faith in their ability to rebuild their lives and realization of their inner strength. “The lowering of suicidal tendencies appears to be strongly associated with optimistic expectations for recovery efforts,” he said.
To estimate the impact of Hurricane Katrina on mental illness and suicidality, the investigators surveyed a statistically representative sample of 1,043 adults from Alabama, Louisiana, and Mississippi, and compared the results with those of the National Comorbidity Survey-Replication conducted between February 2001 and February 2003.
The NCS-R included interviews with 826 adults in the regions later affected by Hurricane Katrina. Both surveys asked identical questions about mental illness and suicidality, and the post-Katrina survey included items associated with trauma-related personal growth.
“The [post-Katrina] survey also assessed personal cognitions that have been identified in previous research to predict adjustment to disasters,” Dr. Kessler said. The survey focused on five dimensions of personal growth, including posttraumatic increases in “emotional closeness to loved ones, faith in the ability to rebuild one's life, spirituality or religiosity, meaning or purpose in life, and recognition of inner strength or competence.”
The comparison of the pre- and posthurricane surveys showed the prevalence of serious mental illness in respondents was 11.3% after Katrina, compared with 6.1% before it, and the prevalence of mild-moderate mental illness was 19.9% after the hurricane, compared with 9.7% before it.
The prevalence of suicidal ideation and plans among respondents estimated to have mental illness was 0.7% after Katrina, compared with 8.4% before it. “The lower conditional prevalence of suicidality was strongly related to two dimensions of personal growth after the trauma,” including faith in individuals' own ability to rebuild their lives and realization of inner strength, Dr. Kessler said. Without these two dimensions, “between-survey differences in suicidality [among mentally ill respondents] were insignificant,” he said.
The investigators hypothesized that the ability to create positive thoughts about the future provide protective “psychological scaffolding” against the suicidality that is often associated with extreme distress. The post-Katrina study “is, to our knowledge, the first to provide quantitative evidence regarding such a pattern in an epidemiological sample of a population that has survived a disaster,” Dr. Kessler said.
The concern, however, “is that the lowering of suicidal tendencies appears to be strongly associated with expectations for recovery efforts that might not be realistic,” he said, noting that it's important to recognize the low prevalence of suicidality might be temporary if positive expectations are not met as time goes on.
The findings could have significant implications in the development of future disaster planning efforts. “A systematic investigation of posttraumatic [positive cognitions and] personal growth might be useful in guiding public health efforts delivered through the mass media in the aftermath of disasters,” said Dr. Kessler, noting that previous studies have shown that public health messages can have a significant impact on psychological reactions to disasters.
The message for policy makers “is that communications with survivors can sometimes build on the temporary reprieve from suicidal tendencies afforded by these protective cognitions,” Dr. Kessler said. “Efforts on the part of public officials to control expectations as recovery moves forward without destroying the positive cognitions related to these expectations could prove crucial in the process of continued psychological recovery.”
The current report, published in a special online edition of the Bulletin of the World Health Organization (www.who.int/bulletin/en
The National Institute of Mental Health and the Office of the Assistant Secretary of Health and Human Services for Planning and Evaluation are funding the project.
Anxiety and Personal Growth Emerged
Baseline interviews with the Hurricane Community Advisory Group, a statistically representative sample of 1,043 Hurricane Katrina survivors from Alabama, Louisiana, and Mississippi provide important insight into the posttraumatic stress reactions and personal growth experienced by this population.