Depression Severity Similar Among Primary Care and Psychiatric Clinics

CHAPEL HILL, N.C., March 27 -- Major depression severity is much the same in a psychiatric clinic as it is in the practice of a generalist, reported investigators.

"Conventional wisdom has held that depressed patients in primary care settings are less severely depressed, experience a milder course of illness, have a distinct symptom profile with more complaints of fatigue and somatic symptoms, and are more likely to have accompanying physical complaints than depressed patients seeking psychiatric specialty care," wrote Bradley N. Gaynes, M.D., M.P.H., of the University of North Carolina here, and colleagues in the STAR*D study.

But the study of more than 2,500 patients with major depressive disorder in both primary care and specialty practices found that while there slight differences in some measures, levels of moderately severe depression were similar, the STAR*D team reported in the March/April issue of the Annals of Family Medicine.

Moreover, the distribution of depressive severity scores was identical, whether patients were being seen by their personal physicians or by psychiatrists, they added.

"Our results also confirm and underscore that risk factors for suicidality, such as prior attempts and recent suicidal ideation, are common in both primary care and specialty care settings, although significantly more likely in specialty care settings," the authors wrote.

Patients seen in specialty clinics were also more likely to have their first depressive episode in childhood or adolescence, the authors noted. The study, they added, highlights a need for aggressive management of depression in both primary care and specialty practices.

The study looked at participants in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial. That trial, initially reported in the New England Journal of Medicine in March 2006, found that about one-fourth of patients who do not achieve remission of depression on citalopram (Celexa) may benefit from a switch to a different drug -- including another SSRI -- or from augmentation of the first drug with other agents.

The STAR*D authors also found that more than four weeks of therapy with a first-line agent may be required to determine whether a change in therapeutic strategy may be necessary.

In the current study, Dr. Gaynes and colleagues collected baseline data about a distinct validation cohort of 2,541 participants in 18 primary care and 23 psychiatric clinics in 14 U.S. regional centers.

The participants, 42% of them seen in primary care practices, met broadly inclusive eligibility criteria requiring a DSM-IV diagnosis of single or recurrent non-psychotic major depressive disorder, and a minimum depressive symptom score for moderate severity (> 14) on the 17-item Hamilton Rating Scale for Depression.

The primary outcome measures were scores on the 30-item Inventory of Depressive Symptomatology - Clinician Rated (IDS-C30) and on the Psychiatric Diagnostic Screening Questionnaire.

When the authors compared the items on the IDS-C30 scale for the two groups and adjusted the data for demographics, length of current depressive episode and general medical condition, they found "borderline significant but largely clinically unimportant differences in symptom items of the essential mood components: primary care participants tended to be less likely to complain of depressed mood (96.6% versus 97.6%; P=0.053) and were slightly less likely to have anhedonia (80.6% versus 85.7%; P= 0.002)."

Regardless of the treatment setting participants were equally likely to have the core symptoms of appetite or weight change, sleep disturbance, psychomotor slowing, loss of energy, or feelings of worthlessness.

Patients in specialty practices were slightly but significantly more likely, however, to report suicidal ideation within the past week (51.4% versus 42.8%; adjusted P<0.001 by IDS-C30), and to have attempted suicide (18.1% versus 13.1%; P = <0.001).

Patients seen in psychiatric clinics were also slightly more likely to endorse psychomotor agitation (64.5% versus 60.7%; P=0.019) and decreased concentration (82.5% versus 76.6%; P = 0.008).

When they looked at core depressive symptoms or concurrent psychiatric disorders, however, they found that they were not substantially different between treatment settings.

About half of all patients in each setting had an anxiety disorder (48.6% of primary care patients, and 51.6% of specialty care patients, P=0.143). Social phobia was the most common form of anxiety disorder, and was slightly higher among patients seen by psychiatrists, occurring in 25.3% of patients in primary care, compared with 32.1% of those in specialty care, P = 0.002)

"For outpatients with non-psychotic major depressive disorder, depressive symptoms and severity vary little between primary care and specialty care settings," the investigators wrote. "In this large, broadly inclusive U.S. sample, the risk factors for chronic and recurrent depressive illness were frequently present, highlighting a clear risk for treatment resistance and the need for aggressive management strategies in both settings."

The authors pointed out that "these findings do not apply to those clinic patients who are not identified as depressed, a well described group who may represent as much as 50% of those depressed in primary care settings. Rather, our results apply to those populations of primary care and specialty care settings who are identified as being depressed. This group remains at marked risk of not receiving adequate treatment regardless of treatment location."