Two intravenous infusions of ketamine (0.5 mg/kg) given 24 hours apart, added to usual treatment, led to full remission of suicidal ideas by day 3 in 63.0% of hospitalized patients with suicidal ideation, compared to 31.6% with placebo. The benefit was strongest in patients with bipolar disorder (odds ratio 14.1), not significant in those with depressive disorder (odds ratio 1.3), and intermediate for other disorders (odds ratio 3.7). At six weeks, remission remained high in the ketamine group (69.5% vs 56.3%) but was no longer statistically significant. Side effects were limited, with no manic or psychotic symptoms observed. An analgesic effect on mental pain may explain the anti-suicidal action.
Mindfulness abilities are linked to dissociation in people with PTSD, and the relationship is mediated by emotional non-acceptance and attentional difficulties. In a sample of 90 patients with PTSD, those with more severe dissociative symptoms reported lower mindfulness capacity. Statistical analysis showed that mindfulness indirectly reduced dissociation through improved emotional acceptance and attention, supporting a model where these two components are active mechanisms of mindfulness. The findings suggest mindfulness-based interventions might help treat dissociation, but clinical trials are needed to confirm causality.