Michael E. Thase
Background: Venlafaxine hydrochloride, a structurally novel
antidepressant, is also the first nontricyclic serotonin/norepinephrine reuptake
inhibitor. Although venlafaxine has an overall side effect and safety profile that is
comparable to other newer antidepressants, it can cause both transient and sustained
elevations of supine diastolic blood pressure (SDBP), probably the result of noradrenergic
potentiation.
Method: Presented here is a meta-analysis of original data on blood
pressure, using both random effects and a multivariate survival analyses. The sample
consisted of 3744 patients with major depression who were studied in controlled clinical
trials comparing venlafaxine with imipramine and/or placebo. Patients were treated for 6
weeks of acute phase therapy; some responders received up to 1 year of continuation
phase therapy.
Results: Venlafaxine and imipramine were associated with small, but
statistically significant, increases in SDBP during acute phase therapy. When compared
with imipramine and placebo, venlafaxine was also associated with a greater proportion of
persistent elevations of SDBP during continuation therapy. The effect of venlafaxine was
highly dose dependent, and the incidence of elevated SDBP was statistically and clinically
significant only at dosages above 300 mg/day. Venlafaxine did not adversely affect the
control of blood pressure for patients with preexisting high blood pressure or elevated
baseline values.
Conclusion: Venlafaxine has a dose-dependent effect on SDBP that is
clinically significant at high dosages. Concern about blood pressure effects should not
deter first-line use of this effective antidepressant, although more extensive studies of
patients with cardiovascular diseases are still necessary.
J Clin Psychiatry 1998;59(10):502-508
© Copyright 1998 Physicians Postgraduate Press, Inc.