Short-term efficacy of tricyclic antidepressants revisited: a meta-analytic study.
The original data from the placebo-arms and the tricyclic-arms of all parallel randomized controlled three-arm studies, which had been conducted in the period 1979-1991 for a drug under development in order to obtain marketing authorization for the indication major depression, were included in a meta-analysis. Thirty-two placebo-controlled studies including 4314 patients were analyzed. The intention to treat analysis resulted in 46% responders (at least 50% improvement on the Hamilton Depression Rating Scale) in the tricyclic antidepressant group and 31% in the placebo-group (CI(95%-difference) 11.5-17.1%). The number needed to treat for responders was 7 (CI(95%) 5-8). In 10 out of 32 studies, a statistically significant difference in favor of tricyclic antidepressant compared to placebo was found for responders. The responder rate in the placebo-group varied from 6 to 52%. We conclude that tricyclic antidepressants are efficacious in the short-term treatment of major depression. However, the magnitude of the effect is rather modest. Because 69% of the placebo-controlled studies with a tricyclic antidepressant did not show a statistically significant difference in favor of tricyclic antidepressant and the placebo rate varied considerably from study to study, equivalence studies with tricyclic antidepressant as comparator without a placebo-control are not sufficient for demonstrating efficacy. Therefore in major depression, placebo-controlled studies are still necessary to demonstrate efficacy.
Storosum
J G
JG
Medicines Evaluation Board of the Netherlands, Kalvermarkt 53, P.O. Box 16229, 2500 BE, Den Haag, The Netherlands. jg.storosum@cbg-meb.nl
Elferink
A J
AJ
van Zwieten
B J
BJ
van den Brink
W
W
Gersons
B P
BP
van Strik
R
R
Broekmans
A W
AW
D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000008:administration & dosage / Q000627:therapeutic use*; D003866:Depressive Disorder / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010352:Patient Dropouts; D011569:Psychiatric Status Rating Scales; D013997:Time Factors
D000929:Antidepressive Agents, Tricyclic