WASHINGTON, D.C.—Approximately 16 percent of the U.S. adult population will have major depression at some time in their life, and about 13 million Americans had an episode of major depression in the last year, according to an article in the June 18 issue of The Journal of the American Medical Association, a theme issue on depression.

Study co-author Kathleen R. Merikangas, Ph.D., of the National Institute of Mental Health, Bethesda, Md., presented the findings of the study today at a JAMA media briefing on depression at the National Press Club in Washington, D.C. Dr. Merikangas is study co-principal investigator and Dr. Ronald Kessler of Harvard University is the principal investigator.

According to background information in the article, uncertainties exist about the prevalence of major depressive disorder (MDD).

The data for this study were derived from the National Comorbidity Survey Replication (NCS-R), which consisted of a nationally representative face-to-face household survey conducted from February 2001 through December 2002 with 9,090 household residents, ages 18 years or older, residing in the 48 contiguous United States. The criteria used to determine depression were from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), published by the American Psychiatric Association.

The diagnostic instruments used included an expanded version of the World Health Organization's (WHO) Composite International Diagnostic Interview (CIDI); 12-month severity was determined with the Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR), the Sheehan Disability Scale (SDS), and the WHO disability assessment scale (WHO-DAS). The validity of the community interviews was examined through reinterviews by experienced clinicians using the Structured Clinical Interview for DSM-IV.

The researchers found that the prevalence of major depression for lifetime was 16.2 percent (32.6-35.1 million U.S. adults) and for 12-month was 6.6 percent (13.1-14.2 million U.S. adults). Virtually all CIDI 12-month cases were independently classified as clinically significant, with 50 percent manifesting severe depression. The average duration of an episode of depression was four months. Sixty percent of those with major depression during the past year reported substantial impairment in occupational and social functioning. Although about one-half of those with major depression during the past year received some type of treatment, the reported treatment met criteria for being adequate in less than half of the cases. Thus, although more people are currently receiving treatment, only 22 percent of respondents with major depression during the past year reported receiving adequate treatment.

WASHINGTON, D.C.—Nationwide, individuals with depression cost employers $44 billion per year in lost productive time compared to $13 billion among those without depression, according to a study in the June 18 issue of The Journal of the American Medical Association (JAMA), a theme issue on depression.

Lead author Walter F. Stewart, Ph.D., M.P.H., of the Outcomes Research Institute at Geisinger Health Systems, Danville, Pa., presented the findings of the study today at a JAMA media briefing on depression at the National Press Club in Washington, D.C. (Dr. Stewart was employed at AdvancePCS Center for Work and Health, Hunt Valley, Md., at the time the research was conducted.)

According to background information provided by the authors, "Evidence consistently indicates that common conditions including migraine, low back pain, diabetes, allergic rhinitis, gastroesophageal reflux, and depression dominate health-related lost labor time costs. Among these, depression is among the most costly because it is highly prevalent and comorbid with other conditions. Furthermore, although workers with depression are usually present at work, their performance can be substantially reduced."

Dr. Stewart and colleagues analyzed data from the American Productivity Audit and the Depressive Disorders Study to estimate the impact of depression on labor costs, including work absences and reduced performance at work, in the U.S. workforce.

The Depressive Disorders Study is a subsurvey of the American Productivity Audit, a national survey of the U.S. population with 30,523 interviews completed between August 1, 2001 and July 31, 2002. The Depressive Disorders Study and the related estimates are based on the subsample of 3,351 productivity audit interviews conducted between May 20 and July 11, 2002. A total of 1,190 individuals were selected to complete a supplemental interview, including questions on depressive disorders, and a medical and treatment history (692 working participants who screened positive for depression and 435 working participants who screened negative for depression). The excess lost productive time (LPT) costs from depression were derived as the difference in LPT among individuals with depression minus the expected LPT in the absence of depression projected to the U.S. workforce.

On average, "Workers with depression reported significantly more total health-related LPT than those without depression (mean [average], 5.6 hours/week vs. an expected 1.5 hours/week respectively)," the authors report. "United States workers with depression are estimated to cost employers $44.01 billion per year in LPT, an excess of $30.94 billion per year when compared with an expected cost in workers without depression," the authors state. "A total of 81.1 percent of the LPT costs are explained by reduced performance while at work. Major depression accounts for almost half (48.5 percent) of the LPT among workers with depression, again with the majority of the cost explained by reduced performance while at work."

The authors also report that self-reported use of antidepressants in the previous 12 months among those with depression was low, at less than 30 percent, and the average reported treatment effectiveness was only moderate. The researchers found that "any depression was close to two times more prevalent in women than in men, with a marked difference in the prevalence of major depression (women 5.3 percent; men 1.6 percent). Other notable patterns include a strong inverse gradient with increasing education level and, in general, higher prevalence of any depression in relation to lower annual salary levels."

WASHINGTON, D.C.—Cutting-edge brain imaging research has identified regions of the brain that are associated with the development of depressive symptoms, according to an article in the June 18 issue of The Journal of the American Medical Association, a theme issue on depression.

Study lead author J. Douglas Bremner, M.D., of the Emory Center for Positron Emission Tomography, Emory University School of Medicine, Atlanta, presented the findings of the study at a JAMA media briefing on depression at the National Press Club in Washington, D.C.

According to background information in the article, positron emission tomography (PET - a brain imaging technique) measurement of brain metabolism has shown that patients receiving selective serotonin reuptake inhibitors (SSRIs) who have a tryptophan (a chemical in the brain) depletion-induced return of depressive symptoms have an acute decrease in metabolism in brain regions such as the orbitofrontal cortex, dorsolateral prefrontal cortex, and thalamus. Many patients with depression in remission while taking norepinephrine reuptake inhibitors (NRIs) (but not SSRIs) as antidepressants experience a brief return of depressive symptoms with depletion of norepinephrine (a hormone) and dopamine (a chemical in the brain) from the drug alpha-methylparatyrosine (AMPT).

The purpose of this study was to assess changes in the brain associated with AMPT-induced return of depressive symptoms in patients with depression in remission while taking NRIs. The study was a randomized, controlled double-blind trial in which 18 patients recruited in 1997-2000 from the general community who had depression in remission while taking NRIs had PET imaging in a psychiatric research unit following AMPT and placebo administration.

The researchers found that AMPT-induced return of depressive symptoms was experienced by 11 of the 18 patients and led to decreased brain metabolism in a number of brain regions, with the greatest magnitude of effects in orbitofrontal and dorsolateral prefrontal cortex and thalamus. Increased resting metabolism in prefrontal and limbic areas predicted vulnerability to return of depressive symptoms.

"Administration of AMPT with depletion of norepinephrine and dopamine resulted in decreased metabolism (from an elevated baseline) in patients who developed depressive symptoms, and increased metabolism (from a relatively lower baseline) in patients who did not develop depressive symptoms," the authors write. Regarding the serotonin and norepinephrine neurotransmitter systems, the authors conclude that "the research suggests that disruption of either neurochemical system can lead to depression, probably by affecting the common brain regions that they [have input to]."

WASHINGTON, D.C.—Cognitive behavior therapy (CBT) can help patients following myocardial infarction (heart attack) deal with depression and low perceived social support, but the intervention does not improve survival or reduce cardiac risk, according to a new study in the June 18 issue of The Journal of the American Medical Association (JAMA), a theme issue on depression.

Corresponding author Susan M. Czajkowski, Ph.D., from the National Heart, Lung, and Blood Institute, Bethesda, Md., presented the findings of the study today at a JAMA media briefing at the National Press Club in Washington, D.C.

"Cardiovascular disease is the leading cause of death and a major cause of morbidity and disability in the United States, with an estimated six million people having symptomatic coronary heart disease (CHD)," the authors provide as background information. "Recent studies have shown that depression and low perceived social support (LPSS) are associated with increased cardiac morbidity and mortality in CHD patients." Individuals with LPSS report having few people to turn to for support, according to the authors. They may feel that existing relationships are unsatisfying, and can have behavioral and social skill deficits that contribute to a lack of closeness or connection with others.

Dr. Czajkowski and investigators from the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) clinical trial enrolled 2,481 myocardial infarction (MI) patients (1,084 women, 1,397 men) from 73 hospitals affiliated with eight clinical centers from October 1996 to April 2001. Patients were assigned randomly either to the intervention (n=1,238) or the usual care group (n=1,243). "CBT was used as the basis for the ENRICHD intervention because of its efficacy in treating depressed noncardiac patients and its ability to address a range of issues involving distress and behavioral problems," the authors write. The CBT (individual and/or group therapy sessions) was supplemented with a selective serotonin reuptake inhibitor (SSRI) antidepressant when indicated. Each participant was screened for the presence of depression or LPSS. Patients in usual care received the usual care provided by their physicians as well as written material about heart health. At baseline, an electrocardiogram was performed, and demographic, medical history, current medication use and physical examination data were recorded. Follow-up visits occurred six months after randomization and annually thereafter.

"Improvement in psychosocial outcomes at six months favored treatment ...," the authors report. "After an average follow-up of 29 months, there was no significant difference in event-free survival between usual care (75.9 percent) and psychosocial intervention (75.8 percent). There were also no differences in survival between the psychosocial intervention and usual care arms in any of the three psychosocial risk groups (depression, LPSS, and depression and LPSS patients)."

NATIONWIDE STUDY SHOWS DEPRESSION IS COMMON, AS IS INADEQUATE TREATMENT