Katrina Spawned Mental Disorders But Not Thoughts of Suicide

BOSTON, Aug. 30 -- For those who lived through Hurricane Katrina, mental disorders doubled but thoughts of suicide did not rise, with the experience bringing out newly found resiliency.

In a survey of Gulf Coast residents who weathered Katrina, the prevalence of serious mental health problems jumped from 6.1% before the storm and devastation to 11.3% afterward, reported Ronald Kessler, Ph.D., of Harvard Medical School, and colleagues, online in the Bulletin of the World Health Organization.

The prevalence of mild-to-moderate mental disorders also doubled, from 9.7% before Katrina to 19.9% afterward. Yet among those respondents who were estimated to have mental illness, the prevalence of both suicidal ideation and plans for suicide declined significantly, the authors found.

"The increase in mental illness among Katrina survivors is not surprising, but the low suicidality is a surprise," said Dr. Kessler, a professor of health care policy. "Our concern, though, is that this lowering of suicidal tendencies appears to be strongly associated with expectations for recovery efforts that might not be realistic."

In a separate analysis of survey results available on the Harvard Medical School Web site, the researchers also found that although 85% of Katrina survivors surveyed reported substantial loss of income, finances, and housing, and more than a third suffered from five or more hurricane-related stressors, there was a surprising degree of resiliency. Nearly two-thirds of respondents said their lives were about the same as they had been before the storm, and more than 13% said their lives were actually better.

To get an idea of the effect that Katrina had on mental illness and suicidality among survivors, the authors compared results of a post-hurricane survey with those from the National Comorbidity Survey-Replications, which is conducted every 10 years to gauge the mental health of the nation.

The authors used survey data collected from February 2001 through February 2003 from a subset of 828 people living in U.S. Census areas that were later affected by Katrina, and compared them with those of a new sample collected after the storm (from Jan. 19 through March 31, 2006) from 1,043 adults who lived in the same areas both before and after the storm.

The primary outcome measures used were the K6 screening scale for serious and mild-to-moderate mental illnesses, as well as questions designed to tease out information about suicidal ideation, suicide plans, or suicide attempts.

They found that while the prevalence of both serious and mild-to-moderate disorders approximately doubled -- a finding that jibes with other studies of mental illness following a traumatic event -- the prevalence of suicidal ideation was 8.4% before Katrina, but only 0.7% after. Similarly, plans for suicide occurred in 3.6% of those surveyed pre-Katrina, but only 0.4% of those surveyed after the storm.

"This lower conditional prevalence of suicidality was strongly related to two dimension of personal growth after the trauma," the authors wrote. The dimensions were an individual's faith in his/her ability to rebuild his/her life, and "realization of inner strength." In the absence of these two variables, the between-survey differences were not significant, the authors found.

"The immediate take-home message for disaster recovery and policy makers," Dr. Kessler said, "is that communications with survivors can sometimes build on the temporary reprieve from suicidal tendencies afforded by these protective cognitions. Efforts on the part of public officials to control expectations as practical recovery moves forward without destroying the positive cognitions related to these expectations could prove crucial in the process of continued psychological recovery."

In the analysis published on the Harvard Medical School Web site, the authors reported that in tracking surveys of Katrina survivors, one-fourth reported having nightmares about their experiences in the hurricane in the previous month, and half of all those who lived in New Orleans before the hurricane reported having nightmares.

More than half of the respondents (including more than three-fourth of New Orleans residents) reported being more irritable or angry than usual.

But the authors also found evidence of "an enormous amount of strength and personal growth."

In all, 88.5% respondents said that their experiences with the hurricane helped them develop a deeper sense of meaning or purpose in life, and faith in their own abilities to rebuild their lives was reported by 83.4% of the total sample, and 73.8% of the New Orleans residents.

"It is important to recognize that this perception of strength is not something that was perceived by respondents to be there all along, even before the hurricane," the authors wrote, "but as something that respondents discovered in themselves as part of the process of struggling with the adversities caused by the hurricane."

They suggested personal growth reported by respondents might be protective against suicidality among Katrina survivors with clinically significant anxiety and depression.

The authors acknowledged that their findings are limited by the fact that they compared a survey of all people in a census district (pre-Katrina) with a randomly selected sample (post-storm). But the similarity of their findings to those of other studies estimating the prevalence of suicidal thoughts and mental illness following traumatic events lends credence to their results, they wrote.