Sept. 29, 2006 — -- Despite a current media frenzy over high-profile suicides -- including, most recently, two Sago mine workers who lost 12 comrades to a mining disaster -- a study published in the American Journal of Public Health reports a decline in suicide rates from 1970 to 2002.
And though there has been concern that new antidepressants released in the late 1980s may increase the risk of suicide, especially among adolescents, the study shows that there are no clinical studies to prove this.
The study, led by Dr. Robert E. McKeown at the University of South Carolina, Columbia, looked at four age groups and found that suicide rates for the youngest (15 to 24 years) and oldest (65 years and older) age groups peaked in the late 1980s and early 1990s and have since steadily declined.
For the middle two age groups, rates only recently began to fall (45 to 64 years), or remained stable in recent years (25 to 44 years). Suicide rates for all age groups were lower in 2002 compared with 1970.
Suicide went from ranking as the eighth leading cause of death in 1998 to the 11th leading cause of death in 2003. Suicide, however, remains a national killer. In 2003, nearly 11 out of every 100,000 poeple living in the United States committed suicide.
According to the authors, there are several possible reasons for the drop in suicide rate. The economic prosperity of the 1990s meant that younger people didn't have a hard time finding jobs, and older people earned enough from their investments to have a comfortable retirement.
An increase in healthy life expectancy may also be a contributing factor. As people live longer, with strong social networks, they don't suffer as much from loneliness and depression, thereby reducing the risk of suicide.
Suicide rates began to fall around the same time that a newer class of antidepressants, serotonin-selective reuptake inhibitors (SSRIs), hit the market in 1988. It was thought that the declining suicide rates were attributable to these new drugs, which include Prozac and Paxil.
By 1999, three of the four SSRIs on the market were ranked among the top 10 drugs most frequently used in the United States. The SSRIs had safer side effects than older antidepressants, which meant that patients were more likely to take them if they were prescribed. Many in the medical community and media linked their widespread use to suicide rates.
The SSRIs, however, do not seem to have impacted the middle-aged groups (25 to 44 years and 45 to 64 years) the same way they did the youngest and oldest groups. While suicide rates for the youngest and oldest age groups started falling shortly after the introduction of SSRIs, rates for the 25-to-44-year age group did not start trending downward until 1995, and rates for the 45-to-64 year age group actually increased from 1999 to 2001.
It's important to note that studies cannot prove that increased use of antidepressants lowers suicide rates because a variety of factors related to improved health care could play a role.
"It's certainly possible that lower suicide rates are due to other factors that occur along with increasing antidepressant use, like better access to or greater acceptance of mental health treatment," said Dr. Gregory Simon, psychiatrist and researcher at the Seattle-based Group Health Cooperative.
Some studies, however, have shown up to a two-fold increase in suicide-related behavior among children on SSRIs. There are many theories as to why this may be the case. When a patient's depression improves, but the patient remains suicidal, he or she may have more energy and initiative to carry out a suicide plan.
According to Dr. J. Alexander Bodkin, Chief of the Clinical Psychopharmacology Research Program at McLean Hospital and Assistant Professor at Harvard Medical School, "SSRIs, when clumsily prescribed in too-high initial doses, can make anxiety and other distressing emotions temporarily worse before they get better. This may occasionally lead to increased desperation and even to thoughts of suicide, but very rarely to suicidal actions."
In addition, the side effects of the drugs, including agitation and impulsivity, may increase the risk of suicide. And while the drugs may bring a patient out of depression, they may also cause the patient to go the other extreme. The conversion from depression to mania can increase the risk of suicide.
Because of the concern that SSRIs may increase the risk of suicide, the FDA issued a directive in 2004 requiring all anti-depressants to carry a black-box warning recommending that patients on anti-depressants be closely monitored for worsening depression or signs of suicidality. Whether these warnings will change the number of prescriptions for kids, and whether lowered prescriptions may reverse the trend in falling suicide rates, still remains to be determined.
More research needs to be done on SSRIs to determine whether they increase or decrease the risk of suicide. The factors contributing to the steady drop in suicide rates also need to be identified, so appropriate measures can be taken to ensure they continue in the right direction.