Adequacy of venlafaxine dose prescribing in major depression and hospital resources implications

Abstract

Venlafaxine, a dual serotonin and noradrenaline re-uptake inhibitor, has been found to be effective at doses below 375 mg daily, but for patients with major depression higher doses can be required. In this retrospective naturalistic study, we investigated the effectiveness and resource implications of prescribing higher than standard doses of venlafaxine (tablet preparation). Ninety-six outpatients fulfilling DSM-IV criteria for major depressive disorder were assigned to two demographically matched cohorts: cohort A, receiving high doses (n = 38; doses > or =375 mg/day) and cohort B, receiving standard doses (n = 58; doses <375 mg/day). Data on hospital resources, drugs and medical profiles were extracted from patients' records. Information on cohort A was also obtained before their high-dose regime, while taking standard doses. A within-group analysis of cohort A showed that patients spent fewer days in hospital (P = 0.03) and had fewer outpatients visits (P < 0.01) when on high doses than when on standard doses. A between-group analysis found that cohort A, while on higher doses, had fewer outpatient visits compared with cohort B (P < 0.01). Patients in both groups had satisfactory drug tolerability and efficacy profiles. There were no differences between cohorts with regard to baseline characteristics, a part from the more intensive use of additional medications made by cohort A. Our preliminary investigation suggests that higher doses of venlafaxine may be cost-saving in relation to selected hospital resources. However, one cannot firmly conclude that the change in service use is due to the higher-dose regime, and we recommend further research to ascertain the cost-effectiveness of adequate dose prescribing in patients with poor symptom resolution at lower doses of venlafaxine.