Cannabis Use in People With Obsessive-Compulsive Symptomatology: Results From a Mexican Epidemiological Sample.

Recent studies suggest that the endocannabinoid system could play an important role in the physiopathology of obsessive-compulsive disorder (OCD). There are reports of effective treatment with derivatives of tetrahydrocannabinol (THC). The study of the genetic factor associated with psychiatric disorders has made possible an exploration of its contribution to the pharmacological response. However, very little is known about the genetic factor or the prevalence of cannabis use in the Mexican population with OCD. The objective of this study is to compare the prevalence of use and dependence on cannabis in individuals with obsessive-compulsive symptomatology (OCS) with that of individuals with other psychiatric symptoms (psychosis, depression, and anxiety), and to explore the association between genetic risk and use. The study includes a total of 13,130 individuals evaluated in the second stage of the 2016 National Survey of Drug, Alcohol, and Tobacco Use (Encodat 2016), with genetic analysis (polygenic risk scoring) of a subsample of 3,521 individuals. Obsessive symptomatology had a prevalence of 7.2% and compulsive symptomatology a prevalence of 8.6%. The proportion of individuals with OCS who had ever used cannabis was 23.4%, and of those with cannabis dependency was 2.7%, the latter figure higher than that in individuals with other psychiatric symptoms (hypomania, 2.6%; anxiety, 2.8%; depression, 2.3%), except psychosis (5.9%). Individuals with OCS who reported using cannabis had an increased genetic risk for cannabis dependence but not for OCD. We thus cannot know how the increased genetic risk of cannabis dependence in people with OCD is influenced by their pharmacological response to derivatives of THC. The results, however, suggest paths for future studies.

El polimorfismo 5-HTTLPR y el intento suicida en adolescentes deprimidos / 5-HTTLPR polymorphism and suicidal attempt in depressed adolescents

La Organización Mundial de la Salud reporta que el suicidio es la tercera causa de muerte más frecuente para jóvenes de 15 a 24 años de edad y la sexta causa de muerte para niños de cinco a 14 años de edad. Los trastornos del estado de ánimo, particularmente la depresión, son los responsables de la mayor parte de los suicidios consumados. Este mayor riesgo de suicidio se ha encontrado en adultos y adolescentes. Existe cada vez mayor evidencia respecto de la hipótesis de que la conducta suicida tiene una fuerte contribución genética. Varios estudios han reportado una asociación positiva entre el genotipo "SS" y el alelo "S" del polimorfismo 5-HTTLPR del gen del transportador de serotonina y la conducta suicida. Objetivo El objetivo del presente trabajo fue establecer la asociación de las variantes polimórficas del gen del transportador de serotonina en pacientes adolescentes deprimidos con y sin antecedente de intento suicida y determinar si la presencia del genotipo "SS" estaba asociada a características específicas de la depresión. Método La muestra estuvo conformada por 53 adolescentes con diagnóstico de depresión. El diagnóstico se realizó con la entrevista diagnóstica semi-estructurada K-SADS-PL. Para la extracción del ADN genómico se obtuvo una muestra de sangre de cada uno de los pacientes. Resultados El análisis genético de las frecuencias de genotipos y alelos no mostró diferencias estadísticamente significativas entre los grupos. Sin embargo, aquellos pacientes con el genotipo "SS" tenían mayor frecuencia de desesperanza. En los pacientes con este genotipo también se encontró mayor número de intentos suicidas. Conclusiones No se observaron diferencias en la frecuencia de alelos entre pacientes con y sin intento suicida; sin embargo, el genotipo "SS" se asoció a algunas características de la depresión.

Suicide is a common cause of death in adolescents, being mainly associated with depression. In addition, the "SS" genotype and the "S" allele of 5-HTTLPR polymorphism of SLC6A4 gene of serotonin transporter have been associated with suicidal behavior. The aims of the present study were to compare the frequency of the polymorphism of SLC6A4 gene in depressed adolescents with and without history of suicidal attempt and to determine if the "SS" genotype was associated with specific clinical features. Method The study examined 53 adolescents who were evaluated with the Diagnostic Interview Schedule for Affective Disorders and Schizophrenia for school-aged children-present and lifetime version (K-SADS-PL). A DNA sample was obtained and 5HTTLPR polymorphisms of SLC6A4 gene were analyzed. Results There were no differences in the frequency of genotype and allele frequencies between groups. However, patients with the "SS" genotype reported a higher frequency of hopelessness and a greater number of suicide attempts. Conclusions The frequency of "SS" genotype did not differ between patients with and without suicidal behavior, but patients with this genotype exhibited differences in clinical features of depression which need further study.