What is the evidence for Serotonin and Noradrenaline reuptake inhibitors (SNRIs) for adults with fibromyalgia?
AMSTAR Rating
Summary
Patient Population:
18 studies, double blind RCTs, of 7903 participants with fibromyalgia.
Intervention:
SNRIs in these studies included duloxetine (8 studies), milnacipran (9 studies) and desvenlafaxine (1 study). Study duration ranged from short term/6-12 weeks (11 studies), medium term/13-26 weeks (5 studies) and long term/>26 weeks (2 studies).
Comparison:
Seven of the studies compared duloxetine against placebo, 9 studies compared milnacipran against placebo, one study compared desvenlafaxine with against placebo and pregabalin, and one study compared duloxetine with L-carnitine. Major outcomes of self-reported pain relief of >50%, improved patient global impression, tolerability, and safety were measured.
Outcome:
- Self-reported pain relief of >50% occurred for 31% of the SNRI participants versus 21% of the placebo group (Risk Difference (RD) was 0.09 indicating no clinical benefit, 95% CI 0.07-0.11, 15 pooled studies)
- 51% of the SNRI group reported a “very much” improved global impression compared to 29% of the placebo group (RD was 0.19 indicating a clinical benefit, 95% CI 0.12-0.26, 6 pooled studies)
- 19% of the SNRI group dropped out due to adverse effects versus 10% of the placebo group (RD was 0.07 indicating no clinical difference, 95% CI 0.04-0.10, 15 pooled studied)
- 8% of the SNRI group had a serious adverse event compared to 2.1% of the placebo group (RD was -0.00, 95% CI -0.01-0.00, 13 pooled studies)
Guideline Recommendations
| Source | Recommendation |
|---|---|
| CRA | Supported (Level 1/Grade A) |
Outcomes Assessed
- Benefit
- Harm
- Inconclusive
Pain
Self report (> 50% reduction)
Global Impression
"Much" or "Very Much" Improved
Other
Tolerability
Safety
Relevant Clinical Info
Very low to low quality of evidence RCTs due to indirectness, selective non reporting and publication biases, as all the reviewed studies were sponsored by pharmaceutical companies.
Participant Information
the sample size was 7903
their were 18 studies used.
