RESUMEN
Altered brain activities in suicidal subjects have been reported in a number of neuroimaging studies. However, the activity aberrances were inconsistent in previous investigations. Thus, we aimed to address activity abnormalities in suicidal individuals. Databases were searched to perform a meta-analysis of whole-brain functional MRI studies of suicidal individuals through January 14, 2020. Meta-analyses were conducted using Seed-based d Mapping software. Based on a meta-analysis of 17 studies comprising 381 suicidal individuals and 642 controls, we mainly found that increased activity in the bilateral superior temporal gyrus, left middle temporal gyrus, and bilateral middle occipital gyrus, along with decreased activity in the right putamen and left insula, were detected in suicidal individuals compared with nonsuicidal subjects. To reduce methodological heterogeneity between the included studies, subanalyses of behavioral domains were conducted, and the right superior temporal gyrus was found to increase in all subanalyses of domains. In subanalyses of suicidal attempters and ideators, suicide attempters displayed hyperactivation in the bilateral superior temporal gyrus and left middle temporal gyrus and blunted responses in the left insula relative to controls. Suicidal ideators demonstrated elevated activation in the right middle occipital gyrus and reduced activity in the right putamen relative to controls. The bilateral superior temporal gyrus was the most robust finding, replicable in all data sets in the jackknife sensitive analysis. Moreover, increased activity in the right superior temporal gyrus, left middle temporal gyrus, and right middle occipital gyrus was found to be involved with higher suicide ideation scores. This study revealed several brain regions associated with suicidality. These findings may contribute to our understanding of the pathophysiology of suicide and have important implications for suicide prevention and interventions.
Asunto(s)
Imagen por Resonancia Magnética , Ideación Suicida , Encéfalo/diagnóstico por imagen , Humanos , Neuroimagen , Lóbulo Temporal/diagnóstico por imagenRESUMEN
BACKGROUND: Previous studies have shown that psilocybin has antidepressant effects. In the current study, we aim to explore the dose effects of psilocybin on primary (major depression patients) and secondary depression (depressed cancer patients). METHODS: Published studies concerning psilocybin for depression were retrieved. In accordance with PRISMA guidelines, 6 databases (PubMed, Embase, Web of Science, Cochrane Library, Clinicaltrials.gov 2.3 and WanFang database) were searched for research studies published or still in progress from inception to 30 November, 2020, with language restricted to English and Chinese. Hedges' g of Beck Depression Inventory (BDI) score changes was calculated as the primary outcome. RESULTS: 7 articles were finally included, with a total of 136 participants. In terms of efficacy, Hedges' g was 1.289 (95%CI=[1.020, 1.558], heterogeneity I2=50.995%, p<0.001). As psilocybin dose increases within a certain range, the antidepressive effect declines and then increases, with 30-35 mg/70 kg achieving the optimal therapeutic effect. Subgroup analysis suggested that the antidepressive effect of psilocybin was extremely significant at a relatively high dose (30-35mg/70kg: Hedges' g=3.059, 95%CI=[2.269, 3.849], p<0.001), long-term (>1month: Hedges' g=1.123, 95%CI=[0.861, 1.385], p<0.001) and when used in primary depression patients (Hedges' g=2.190, 95%CI=[1.423, 2.957], p<0.001). LIMITATIONS: Only a small number of studies can be identified of variable quality, thus our conclusions remain preliminary. CONCLUSIONS: Our preliminary results have shown that psilocybin exerts a rapid effect in reducing depressive symptom on primary and secondary depression. The optimal dose of psilocybin may be 30-35mg/70kg or higher; future clinical trials are warranted for further evaluation on its effect.