Effect of high-potency cannabis on corpus callosum microstructure.

BACKGROUND: The use of cannabis with higher Δ9-tetrahydrocannabinol content has been associated with greater risk, and earlier onset, of psychosis. However, the effect of cannabis potency on brain morphology has never been explored. Here, we investigated whether cannabis potency and pattern of use are associated with changes in corpus callosum (CC) microstructural organization, in patients with first-episode psychosis (FEP) and individuals without psychosis, cannabis users and non-users. METHOD: The CC of 56 FEP (37 cannabis users) and 43 individuals without psychosis (22 cannabis users) was virtually dissected and segmented using diffusion tensor imaging tractography. The diffusion index of fractional anisotropy, mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity was calculated for each segment. RESULTS: Across the whole sample, users of high-potency cannabis had higher total CC MD and higher total CC AD than both low-potency users and those who never used (p = 0.005 and p = 0.004, respectively). Daily users also had higher total CC MD and higher total CC AD than both occasional users and those who never used (p = 0.001 and p < 0.001, respectively). However, there was no effect of group (patient/individuals without psychosis) or group x potency interaction for either potency or frequency of use. The within-group analysis showed in fact that the effects of potency and frequency were similar in FEP users and in users without psychosis. CONCLUSIONS: Frequent use of high-potency cannabis is associated with disturbed callosal microstructural organization in individuals with and without psychosis. Since high-potency preparations are now replacing traditional herbal drugs in many European countries, raising awareness about the risks of high-potency cannabis is crucial.

A propósito de un caso de psicosis temprana: un nuevo paradigma en salud mental / About a case of early psychosis: a new paradigm in mental health

La intervención precoz en las fases tempranas de las psicosis ha adquirido una creciente relevancia en los últimos años debido a sus potenciales implicaciones sobre la clínica y la evolución de la enfermedad. Es conocido que tras un primer episodio psicótico hay un "periodo crítico" que se extiende a los cinco años siguientes, siendo esta una fase de alta vulnerabilidad. El abordaje integral e intensivo durante este periodo tiene como finalidad optimizar el proceso de recuperación ayudando al paciente y a su familia a reconstruir sus vidas y evitar recadas. A continuación exponemos la gestión de un caso en un reciente programa de "intervención precoz en psicosis" implementado en nuestra unidad de rehabilitación(AU)

Early intervention in the early phases of psychosis has become increasingly relevant in recent years because of their potential clinical implications for the evolution of the disease. It is known that after a first psychotic episode is a "critical period" that extends to five years, this being a period of high vulnerability. Comprehensive and intensive approach during this period aims at optimizing the recovery process by helping the patient and his family rebuild their lives and prevent relapse. Below are the management of a case in a recent program of "early intervention in psychosis" implemented in our rehabilitation unit(AU)