Comparative efficacy and tolerability among different selective serotonin re-uptake inhibitors and venlafaxine in a naturalistic setting

Guidelines for choice of selective serotonin reuptake inhibitor in depressive illness

The selective serotonin reuptake inhibitors (SSRIs) are the most extensively studied of the newer antidepressants and are increasingly being used as first-line treatment for depression (Anderson et al, 2000). In this article we concentrate on issues that need to be taken into account when selecting one of the five SSRIs marketed in the UK (citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline) for individual patients. We have concentrated on treatment of depression and have not reviewed their use in anxiety disorders because comparative data are lacking.

Venlafaxine extended release in the treatment of painful diabetic neuropathy: a double-blind, placebo-controlled study

To evaluate the efficacy and safety of 6 weeks of venlafaxine extended-release (ER) (75 mg and 150-225 mg) treatment in patients with painful diabetic neuropathy. This multicenter, double-blind, randomized, placebo-controlled study included 244 adult outpatients with metabolically stable type 1 or 2 diabetes with painful diabetic neuropathy. Primary efficacy measures were scores on the daily 100 mm Visual Analog Pain Intensity (VAS-PI) and Pain Relief (VAS-PR) scales. Secondary efficacy measures included the Clinical Global Impressions-Severity of Illness and the Clinical Global Impressions-Improvement, Patient Global Rating of Pain Relief, and percentage of patients achieving 50% reduction in pain intensity. Baseline pain intensity was 68.7 mm (moderately severe). At week 6, the percentage reduction from baseline in VAS-PI was 27% (placebo), 32% (75 mg), and 50% (150-225 mg; P < 0.001 vs placebo). Mean VAS-PR scores in the 150-225 mg group were significantly greater than placebo at week 6 (44 vs 60 mm; P < 0.001). The number needed to treat (NNT) for 50% pain intensity reduction with venlafaxine ER 150-225 mg was 4.5 at week 6. Nausea and somnolence were the most common treatment-emergent adverse events. Seven patients on venlafaxine had clinically important ECG changes during treatment. Venlafaxine ER appears effective and safe in relieving pain associated with diabetic neuropathy. NNT values for higher dose venlafaxine ER are comparable to those of tricyclic antidepressants and the anticonvulsant gabapentin.

Antidepressant use in clinical practice: efficacy v. effectiveness

BACKGROUND

Although the efficacy of antidepressants has been demonstrated in randomised, controlled clinical trials, it is how an antidepressant is used in clinical practice that determines its clinical effectiveness, or real-world efficacy.

AIMS

To explore the frequency with which antidepressants are used at adequate dose and duration to obtain remission of symptoms and prevent relapse in clinical practice and discuss potential implications for clinical outcomes.

METHOD

Studies of antidepressant prescribing were reviewed and comparisons made between antidepressant classes and individual compounds within those classes.

RESULTS

Naturalistic studies show that patients who begin therapy on tricyclic antidepressants often receive sub-therapeutic doses for inadequate duration; conversely, patients who begin therapy on selective serotonin reuptake inhibitors more often receive an adequate dose of therapy for a longer duration. CONCLUSIONS; How antidepressants are used in clinical practice can determine the clinical outcomes that are achieved. Antidepressants that are more forgiving of sub-optimal prescribing and use patterns by providers and patients, respectively, may help to improve real-world efficacy.

[Sexual dysfunctions induced by serotonin reuptake inhibitors]

OBJECTIVE

To assess the incidence of serotonin reuptake inhibitor (SRI) antidepressant-induced sexual dysfunction (SD) and to compare the sexual side effects of SRI.

DESIGN

Naturalistic, prospective, observational study.

SETTING

Two urban health centers.

PATIENTS

235 outpatients (164 women, 71 males) who began treatment with some of the following SRI: fluoxetine, sertraline, paroxetine, citalopram and venlafaxine, who had engaged in regular sexual practices with stable partner, who were suffering from different mental disorders who were being treated with SRI. The assignment to each group was according to clinical criteria.

INTERVENTIONS

Patients completed questionnaires that allowed reporting of both SD induced by the illness and the treatment, evaluating changes in libido, arousal, and orgasm. The patients were observed over 6 months of treatment.

RESULTS

147 patients (62.6%) reported one or more SD related to SRI treatment. There were differences in the incidence between the different SRI: 39% with fluoxetine, 75.5% with paroxetine, 78.8% with sertraline, 28.9% with citalopram and 80% with venlafaxine. In 78.2% of patients the SD showed no improvement by the end of this period. In a predictive logistical regression model of the presence of SD induced by the SRI, the female category and the presence of previous sexual problems were favourable predictors and the treatment with paroxetine, sertraline or venlafaxine were increased the risk of SD.

CONCLUSIONS

SD is one of the most frequent and persistent SRI adverse effect. We recommended to inquiry about SD in patients who were treated with SRI. Significant differences were found in the occurrence of SD between the different SRI. Such data would be particularly valuable to physicians when choosing a specific antidepressant from this therapeutic group.