BOCA RATON, FLA. — An abbreviated Hamilton Depression Rating Scale can quickly assess depression severity and monitor patient response to treatment in a primary care setting, according to a multicenter study.
Complete remission of symptoms is the optimal outcome with depression. However, a validated, brief, comprehensive tool to measure symptoms and remission is unavailable in both mental health and primary care settings, Sidney H. Kennedy, M.D., said at a meeting of the New Clinical Drug Evaluation Unit sponsored by the National Institute of Mental Health.
The full Hamilton Depression Rating Scale (HAMD) is often impractical in primary care settings because of concerns about internal consistency, reliability, and the length of time it takes to administer, Dr. Kennedy told this newspaper. Previously, he and his colleagues confirmed validity of an abbreviated seven-item version of the scale (HAMD-7) in a mood disorder clinic setting (Primary Psychiatry 2003;10:39–42).
To assess its performance in primary care settings, 47 practices across Canada enrolled 454 patients in the study. A majority, 85%, reported the HAMD-7 took 3–6 minutes to administer.
“It is a short, practical rating scale that family physicians see in the same way as [taking] a blood pressure measure. It is easy to do and repeat,” said Dr. Kennedy, psychiatrist in chief at University Health Network, Toronto.
Study participants met DSM-IV-TR criteria for a major depressive episode in the context of major depressive disorder. Patients were acutely depressed (a baseline HAMD score of 18 or greater) and required antidepressant treatment. Treatment remained open-label with flexible dosing throughout the 8-week study.
A total of 410 patients met enrollment criteria and were randomized to the HAMD or HAMD-7 group. Researchers looked for correlation between these two tools and depression symptoms measured with the Montgomery-Asberg Depression Rating Scale (MADRS) and the Clinical Global Impression Scale for Improvement and Severity of Illness (CGI-I/S).
The HAMD-7 consisted of the seven items from the HAMD most often endorsed by depressed patients and most sensitive to treatment change. These items include depressed mood, guilt, work and activities, psychic anxiety, somatic anxiety, somatic general, and suicide.
Changes in HAMD and HAMD-7 scores were similar from baseline to end point. In addition, remission rates were similar between groups. For example, a total of 49% of the HAMD group achieved remission, defined as a score of 7 or less. A total of 40% achieved remission on the HAMD-7, defined as a score of 3 or less. This difference was not statistically significant.
“Our first question was: Would we see the same seven items in the family practice setting? The answer is yes, so we validated the seven-item HAMD in this setting,” said Dr. Kennedy, who is also a professor of psychiatry at University of Toronto. He and his associates also validated a cutoff score of 3 for remission using the HAMD-7 in the family practice setting.
A significant proportion of HAMD and HAMD-7 patients achieved a priori response, defined as a 50% or greater reduction in scores by study end, compared with baseline. Researchers found 74% of HAMD patients responded to treatment, as did 67% of the HAMD-7 patients, with no significant difference between groups.
There were significant changes, however, in both MADRS and CGI-I/S scores from baseline to study end within each group. For example, mean MADRS scores changed from 28 to 10 in the HAMD group and from 30 to 10 in the HAMD-7 group. Differences in depression severity between groups were not statistically significant.
The HAMD-7 scale is an important tool to gauge effectiveness of antidepressant treatment and to determine when full symptomatic remission occurs in primary care settings, according to the study authors. “We will continue looking at this,” Dr. Kennedy said.
The study was supported by funding from Wyeth Pharmaceuticals. Dr. Kennedy is a consultant and speaker for the company.