Substance use disorders are a group of diseases that are associated with social, professional, and family impairment and that represent a high socio-economic impact on the health systems of countries around the world. These disorders present a very complex diagnosis and treatment regimen due to the lack of suitable biomarkers supporting the correct diagnosis and classification and the difficulty of selecting effective therapies. Over the last few years, several studies have pointed out that these addictive disorders are associated with systemic and central nervous system inflammation, which could play a relevant role in the onset and progression of these diseases. Therefore, identifying different immune system components as biomarkers of such addictive disorders could be a crucial step to promote appropriate diagnosis and treatment. Thus, this work aims to provide an overview of the immune system alterations that may be biomarkers of various addictive disorders.

Despite substance use disorders (SUD) being one of the leading causes of disability and mortality globally, available therapeutic approaches remain ineffective. The difficulty in accurately characterizing the neurobiological mechanisms involved with a purely qualitative diagnosis is an obstacle to improving the classification and treatment of SUD. In this regard, identifying central and peripheral biomarkers is essential to diagnosing the severity of drug dependence, monitoring therapeutic efficacy, predicting treatment response, and enhancing the development of safer and more effective pharmacological tools. In recent years, the crucial role that the endocannabinoid system (ECS) plays in regulating the reinforcing and motivational properties of drugs of abuse has been described. This has led to studies characterizing ECS alterations after exposure to various substances to identify biomarkers with potential diagnostic, prognostic, or therapeutic utility. This review aims to compile the primary evidence available from rodent and clinical studies on how the ECS components are modified in the context of different substance-related disorders, gathering data from genetic, molecular, functional, and neuroimaging experimental approaches. Finally, this report concludes that additional translational research is needed to further characterize the modifications of the ECS in the context of SUD, and their potential usefulness in the necessary search for biomarkers.

Cumulative evidence has pointed out cannabinoid CB2 receptors (CB₂r) as a potential therapeutic key target for treating alcohol use disorder (AUD). This review provides the most relevant results obtained from rodent and human studies, including an integrative section focused on the involvement of CB₂r in the neurobiology of alcohol addiction. A literature search was conducted using the electronic databases Medline and Scopus for articles. The search strategy was as follows: “Receptor, Cannabinoid, CB2” AND “Alcohol-Related Disorders” AND “human/or patients”; “Receptor, Cannabinoid, CB2” AND “Alcohol” OR “Ethanol” AND “rodents/or mice/or rats”. Pharmacological approaches demonstrated that the activation or blockade of CB₂r modulated different alcohol-addictive behaviors. Rodent models of alcoholism revealed significant alterations of CB₂r in brain areas of the reward system. In addition, mice lacking CB₂r (CB₂KO) show increased alcohol consumption, motivation, and relapse alterations. It has been stressed that the potential neurobiological mechanisms underlying their behavioral effects involve critical elements of the alcohol reward system. Interestingly, recent postmortem studies showed CNR2 alterations in brain areas of alcoholic patients. Moreover, although the number of studies is limited, the results revealed an association between some genetic alterations of the CNR2 and an increased risk for developing AUD. This review provides evidence that CB₂r may play a role in alcohol addiction. Clinical studies are necessary to figure out whether CB₂r ligands may prove useful for the treatment of AUD in humans.

El dolor crónico, que afecta al 20-26 % de los adultos, impacta profundamente en calidad de vida y los costos socioeconómicos. El análisis de perfiles permite individualizar tratamientos, identificar subgrupos de pacientes y diseñar estrategias terapéuticas personalizadas, mejorando resultados y eficiencia sanitaria. Objetivo principal: establecer clústeres de pacientes basados en su dolor y obtener una herramienta que permita identificar pacientes en base a la clusterización desarrollada. Se realizó un estudio descriptivo, transversal, multicéntrico en pacientes con dolor que acuden a la farmacia comunitaria. Se usaron técnicas de agrupamiento no supervisado para detectar patrones en pacientes con dolor agudo y crónico, seguidas de análisis estadísticos y algoritmos supervisados para la predicción y evaluación del cuestionario. En base a estos hallazgos, se desarrolló una herramienta capaz de predecir la pertenencia de los distintos grupos identificados. El análisis identificó 4 perfiles en dolor agudo y 5 en crónico, con el subgrupo 1 mostrando los peores resultados en ambos casos. El modelo de clasificación, para predecir nuevos datos, alcanzó una exactitud del 64.52 % en dolor agudo y 85.56 % en crónico con los datos disponibles. Se identificaron cuatro perfiles de pacientes con dolor agudo y cinco con dolor crónico, lo que facilita la personalización del tratamiento. La farmacia comunitaria, por su accesibilidad, permite un seguimiento continuo, mejorando la adherencia, ajustando tratamientos y coordinando la atención sanitaria. La herramienta de clasificación permitirá analizar a los pacientes mediante variables psicométricas, mejorando el manejo del dolor.