Background: Potential cardiovascular side effects from venlafaxine-XR must be considered when prescribing this medication, especially in geriatric patients, who often present with comorbid medical conditions.
Methods: Participants age 60 and older with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of a major depressive episode without psychotic features were treated openly with venlafaxine-XR for 12 weeks during which venlafaxine-XR was titrated based on tolerability and response according to predefined guidelines. Sitting and standing blood pressures and heart rates were measured. A 12-lead electrocardiogram was obtained at baseline and at week 12.
Results: Sixty-two participants started treatment; 59 completed at least two weeks of the 12-week study. The mean final dose of venlafaxine-XR was 195.5 mg/day (standard deviation: 72.2). Twenty-four percent (95% confidence interval [CI]: 7.3%-40.7%) of initially normotensive participants and 54% (95% CI: 34.3%-74%) of those with preexisting hypertension experienced an increase in blood pressure. Twenty-nine percent (95% CI: 14.6%-43.4%) of participants developed orthostatic hypotension. Two participants experienced a clinically significant increase in QTc interval. One participant reported new-onset mild dizziness, whereas four participants reported new-onset tachycardia or palpitation. Overall, 17 unique participants (28.8%; 95% CI: 17.3%-40.4%) experienced a new-onset cardiovascular problem, potentially related to the study medication.
Conclusion: Overall, venlafaxine-XR was well tolerated. However, similar to previous reports, venlafaxine-XR was associated with some undesirable cardiovascular effects in some of the participants. Systematic monitoring of cardiovascular parameters during treatment with venlafaxine-XR should be strongly recommended, especially in the elderly.