- Patients with major depressive disorder (MDD) and higher baseline plasma serotonin (5-HT) levels had a better therapeutic response to selective serotonin reuptake inhibitor (SSRI) treatment than those with lower levels.
- A larger decrease in plasma 5-HT during treatment was associated with a better SSRI response.
Why this matters
- Previous studies on the association between baseline plasma 5-HT and response to SSRIs yielded conflicting results.
- Study included 37 patients with MDD and 41 healthy controls with plasma 5-HT levels assessed at baseline.
- 26 of 37 patients with MDD underwent 8 weeks of open-label outpatient treatment with SSRI antidepressant sertraline, after which plasma 5-HT levels were measured again.
- Treatment response of ≥50% and
- Funding: National Institute of Mental Health.
- Sertraline treatment responders (P=.036) and healthy controls (P=.004) had significantly higher baseline plasma 5-HT levels vs nonresponders.
- SSRI treatment was associated with a significant decrease in plasma 5-HT among all patients treated for MDD (t, 6.2; P=.000003).
- Decrease in plasma 5-HT levels over treatment was significantly more prominent in sertraline treatment responders vs nonresponders (t, 2.1; P=.047).
- Small study population.
Coauthored with Antara Ghosh, PhD