Comparison
between venlafaxine and selective serotonin
reuptake inhibitors in depression
Serotonin
and noradrenaline are involved in the
pathophysiology of depression, thus the increase
of neurotransmission of both monoamines to treat
this disease may be more efficacious than
serotonergic enhancement alone. Venlafaxine is a
dual serotonin and noradrenaline reuptake
inhibitor (SNRI) that may treat depression more
efficiently than the selective serotonin
reuptake inhibitors (SSRIs). This was the
reasoning behind a recent meta-analysis
comparing the efficacy of venlafaxine and
SSRIs.
Depressed patients, enrolled in eight
randomised, double-blind, controlled trials, had
been treated by venlafaxine/venlafaxine extended
release (XR), SSRIs, or placebo for 8 weeks or
less. The data of these studies were pooled to
statistically analyse the efficacy of these
treatments. The 21-item Hamilton Rating Scale
for Depression (HAM-D(21)), Montgomery-Asberg
Depression Rating Scale (MADRS), and Clinical
Global Impressions-Global Improvement (CGI-I)
and CGI-Severity of Illness (CGI-S) were used to
measure the mean changes from
baseline. Response rates derived from these
scales were also compared.
The mean HAM-D(21) score decrease was different
between venlafaxine (14.5) and SSRIs (12.6) and
between both drug treatments and placebo (11.3).
The mean MADRS scores were also decreased
to a greater extent by venlafaxine than by SSRIs
(17.8 vs 15.9), and both treatments were better
than placebo (12.9). Response (> 50% decrease
in scores) rates on the HAM-D, MADRS and CGI-I
were 71%, 64%, and 67%, respectively, for
venlafaxine, 64%, 57%, and 59%, respectively,
for SSRIs, and 50%, 42%, and 41%, respectively,
for placebo.
This analysis is another confirmation that the
SNRI, venlafaxine, is more effective than SSRIs
in treating depression. The greater improvement
obtained with the SNRI is likely due to its
enhancing effect on both, serotonergic and
noradrenergic, systems. Biol
Psychiat 52: 1166-1174, 2002