A large number of systematic reviews and guidelines have been published in recent years to assist clinicians in prescribing the best antidepressants for treating depression. This new meta-analysis conducted by researchers from Austria and the US, sets out to compare the benefits and harms of second generation antidepressant drugs in the treatment of major depressive disorder.
The research team conducted a systematic search of databases and various sources of unpublished data. For the assessment of efficacy, they sought head-to-head RCTs of at least 6 weeks’ duration comparing two drugs (placebo-controlled studies were included for indirect comparisons). For harms, they examined data from both RCTs and observational studies (including at least 1,000 patients, with follow-up of ≥12 weeks).
They included 234 trials in total, 118 of which were head-to-head studies. Unsurprisingly, the majority of trials included were sponsored by the pharmaceutical industry.
Here’s what they found:
- No clinically relevant differences in efficacy or effectiveness were detected for the treatment of acute, continuation and maintenance phases of major depressive disorder
- No differences in efficacy were seen in patients with accompanying symptoms or in subgroups based on age, sex, ethnicity, or comorbid conditions
- Individual drugs differed in onset of action, adverse events, and some measures of health-related quality of life
The authors concluded:
Current evidence does not warrant recommending a particular second-generation antidepressant on the basis of differences in efficacy. Differences in onset of action and adverse events may be considered when choosing a medication.
Prescribers of antidepressants may be interested in the comparative adverse events table found on page 780 of the paper (see PDF link below).
Gartlehner G, Hansen RA, Morgan LC, Thaler K, Lux L, Van Noord M, Mager U, Thieda P, Gaynes BN, Wilkins T, Strobelberger M, Lloyd S, Reichenpfader U, Lohr KN. Comparative Benefits and Harms of Second-Generation Antidepressants for Treating Major Depressive Disorder: An Updated Meta-analysis (PDF). Ann Intern Med. 2011 Dec 6;155(11):772-85.
I notice that in some of the analyses the authors use the “weighted mean difference of changes on the Hamilton Rating Scale for Depression (HAM-D) or the Montgomery-Asberg Depression Rating Scale (MADRS)”. This method was also used to calculate the effect size by Kirsch et al. (2008).
Do you happen to know why this method is used rather than the difference between post-treatment means? Comparing change scores seems a strange way to go about it.
Kirsch I, Deacon BJ, Huedo-Medina TB, Scoboria A, Moore TJ, et al. 2008 Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration. PLoS Med 5(2): e45. doi:10.1371/journal.pmed.0050045