title: Differential effects of venlafaxine in the treatment of major depressive disorder according to baseline severity.
abstract: In this meta-analysis, we compare the relative efficacy of venlafaxine to selective serotonin reuptake inhibitors (SSRIs) in patients with major depressive disorder classified according to baseline disease severity. Data from 31 double-blind randomised clinical trials comparing venlafaxine and SSRIs (intent-to-treat n = 6,492) were pooled. For this secondary analysis, patients were stratified into groups based on baseline HAM-D(17) total score (>or=30, <30, >or=25, and <25). Remission rates (HAM-D(17) < 8) were analyzed for each subgroup using Fisher's exact test to compare treatment effects between venlafaxine and SSRIs; last observation carried forward (LOCF) and observed cases (OC) data were analyzed. The number needed to treat (NNT) to benefit was determined for each analysis. Statistically significant remission rate differences, favoring venlafaxine, were seen in LOCF and OC analyses for each subgroup. In patients with baseline HAM-D(17) < 25 (n = 3,928) the differences were (LOCF) 7.3 [P < 0.001; NNT = 14] and (OC) 6.2 [P = 0.003; NNT = 16], and in patients with baseline HAM-D(17) >or= 25 (n = 2,564) were (LOCF) 5.7 [P = 0.002; NNT = 17] and (OC) 6.7 [P = 0.009; NNT = 15]. In patients with baseline HAM-D(17) < 30 (n = 5,836) the differences were (LOCF) 6.4 [P < 0.001; NNT = 16] and (OC) 5.5 [P = 0.001; NNT = 18], and in patients with baseline HAM-D(17) >or= 30 (n = 656) were (LOCF) 8.9 [P = 0.015; NNT = 11] and (OC) 14.8 [P = 0.003; NNT = 7]. In conclusion, these analyses demonstrate that venlafaxine may be superior to SSRIs in achieving remission in both mild/moderate and severely depressed patients. The greater difference in remission rates among patients with baseline HAM-D(17) >or= 30 suggests a more pronounced clinical benefit that may be achieved with venlafaxine in severely depressed patients.
authors.affiliation: Department of Medical Affairs, Wyeth Pharma GmbH, 48159 Münster, Germany. schmitA2@wyeth.com
authors.forename: Andreas B
authors.initials: AB
authors.lastname: Schmitt
authors.forename: Michael
authors.initials: M
authors.lastname: Bauer
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Volz
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Moeller
authors.forename: Qin
authors.initials: Q
authors.lastname: Jiang
authors.forename: Philip T
authors.initials: PT
authors.lastname: Ninan
authors.forename: Peter-Andreas
authors.initials: PA
authors.lastname: Loeschmann
mesh_terms: D000328:Adult; D000368:Aged; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use*; D003511:Cyclohexanols / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011569:Psychiatric Status Rating Scales; D012016:Reference Values; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013997:Time Factors; D000069470:Venlafaxine Hydrochloride
chemical_list: D018687:Antidepressive Agents, Second-Generation; D003511:Cyclohexanols; D017367:Selective Serotonin Reuptake Inhibitors; D000069470:Venlafaxine Hydrochloride