Background: It is well established that depressive disorders are more prevalent in women; however gender differences in the pharmacological response to antidepressants are not a consistent finding in all reports. It is considered that this discrepancy can be explained by the fact that in most clinical trials drug use for comparative purposes is not completely different. In this study gender differences in antidepressant response with citalopram (CTP), a selective serotonin reuptake inhibitor and reboxetine (RBX), a selective noradrenaline reuptake inhibitor were evaluated in a group of young men and premenopausal women.
Method: Eighty-six depressed patients 18 to 40 years old participated in an 8-week double-blind clinical trial. Subjects were divided in four groups according to sex and treatment assignation: females treated with CTP (n = 25) or RBX (n = 23), and males treated with CTP (n = 19) or RBX (n = 19). Response was determined using HDRS and BDI.
Results: ANOVA analysis considering change in HDRS scores from baseline to last evaluation found a significant interaction between gender and type of treatment. Females treated with CTP showed a significantly greater response than females treated with RBX, while in men no differences were observed for both drugs.
Limitations: Replication using larger sample size and longer treatment periods is required.
Conclusions: These results support previous findings which show that premenopausal women respond better than men to serotonergic antidepressants. They also support that a plausible interaction between gonadal hormones and serotonin may explain gender differences in antidepressant response.