A study found that ketamine improved symptoms of depression and pain among patients with treatment-resistant disease. These findings were published in Frontiers in Psychiatry.
This single-arm open-label clinical trial was conducted at the Affiliated Brain Hospital of Guangzhou Medical University in China between 2016 and 2018. Patients (N=104) with treatment-resistant major depressive disorder or bipolar disorder without psychotic symptoms received intravenous infusions of 0.5 mg/kg ketamine 3 times per week for 2 weeks. Depressive outcomes were evaluated using the Montgomery–Åsberg Depression Rating Scale (MADRS) and pain using the short-form McGill Pain Questionnaire (SF-MPQ).
Patients with (n=50) or without pain (n=54) symptoms comprised 52.0% and 48.1% men, 70.0% and 81.5% had suicidality, 20.0% and 14.8% were taking 2 or more antidepressants, 28.0% and 29.6% used mood stabilizers, 44.0% and 51.9% used benzodiazepines, and 48.0% and 57.4% took antipsychotics, respectively.
Patients with severe pain (n=27) reported higher visual analog scale (VAS) (P =.042) and MADRS total pain (P <.001) scores compared with patients with mild pain (n=23) or no pain.
At day 26, ketamine was found to have a significant effect on VAS (b, -0.992; P <.001), sensory index (b, -1.017; P <.001), affective index (b, -1.021; P <.001), present pain (b, -0.989; P <.001), and total pain (b, -0.986; P <.001) scores. There was a significant interaction between ketamine and pre-treatment pain for all instruments (all P <.001).
The safety profile of ketamine was tolerable with only mild psychotomimetic and dissociative symptoms reported.
This study was limited by not including a placebo control.
The study authors concluded, “Our study showed that depressive patients with varying degrees of pain exhibited a significant and rapid improvement in depressive symptoms after 6 infusions of ketamine treatment, and pre-treatment pain symptoms moderated ketamine’s antidepressant effect. Overall, our findings suggest that ketamine may be a novel and promising antidepressant preferentially for the therapy of depression with severe pain.”
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
Lan X, Zhou Y, Wang C, et al. Pre-treatment pain symptoms influence antidepressant response to ketamine in depressive patients. Front Psychiatry. 2022;13:793677. doi:10.3389/fpsyt.2022.793677