Using the Severity of Dependence Scale to screen for DSM-5 khat use disorder

Effects of access condition on substance use disorder-like phenotypes in male and female rats self-administering MDPV or cocaine

Substance use disorder (SUD) is a heterogeneous disorder, where severity, symptoms, and patterns of use vary across individuals. Yet, when rats self-administer cocaine under short-access conditions, their behavior tends to be well-regulated, though individual differences can emerge with long- or intermittent-access. In contrast, significant individual differences emerge when rats self-administer 3,4-methylenedioxypyrovalerone (MDPV), even under short-access conditions, wherein ~30 % of rats exhibit high levels of drug-taking. This study assessed SUD-like phenotypes of male and female rats self-administering MDPV or cocaine by comparing level of drug intake, responding during periods of signaled drug unavailability, and sensitivity to footshock punishment to determine whether: (1) under short-access conditions, rats that self-administer MDPV will exhibit a more robust SUD-like phenotype than rats that self-administer cocaine; (2) female rats will have a more severe phenotype than male rats; and (3) compared to short-access, long- and intermittent-access to MDPV or cocaine self-administration will result in a more robust SUD-like phenotype. Compared to cocaine, rats that self-administered MDPV exhibited a more severe phenotype, even under short-access conditions. Long- and intermittent-access to cocaine and MDPV temporarily altered drug-taking patterns but did not systematically change SUD-like phenotypes. Behavioral and quantitative autoradiography studies suggest phenotypic differences are not due to expression of dopamine transporter, dopamine D2 or D3 receptors, or 5-HT1B, 5-HT2A, or 5-HT2C receptors. This study suggests individuals who use synthetic cathinones may be at greater risk for developing a SUD, and short-access MDPV self-administration may provide a useful method to study the transition to disordered substance use in humans.

Is chewing khat associated with mental health disorders? A scoping review of the content and quality of the current evidence base

BACKGROUND

Khat (Catha edulis) is a plant commonly found in the horn of Africa whose leaves are chewed for their psycho-stimulant effects. Several studies have demonstrated the association between khat use and mental health problems. Nevertheless, evidence is mixed and inconsistent, warranting further review of available studies. This scoping review is aimed at investigating the content and quality of evidence base on the associations between khat use and mental health disorders and suggesting avenues for further research.

METHODS

We used a scoping review methodology to map the existing evidence using PubMed, SCOPUS, Embase, and CINAHL databases. Primary studies focusing on the association between any pattern of khat use and any form of mental health disorders are included. The review focused on all age groups, any study design, all geographical locations, and any publication year. The terms used for searching eligible studies include khat, mental disorders, and various alternative terminologies. Narrative review is employed to present findings.

RESULTS

7,121 articles were found, of which 108 were eligible, conducted across 12 different countries. The majority of the studies was done during the last ten years and the studies mostly employed cross-sectional design. About 10 different categories of mental health disorders have been identified as showing associations with khat use. Despite many contradictory findings between the studies, most of the evidence base suggests that khat use is associated with mental health disorders. Non-specific psychological distress is the most frequently mentioned mental health problem (reported in 26.9% of the studies). Khat use as a predictor variable is mostly assessed using a 'yes/no' category, and as a result, dose-dependent effects of khat use on mental health are not given much consideration.

CONCLUSION

Although most of the studies associate khat use with mental health disorders, the causal relationships are inconclusive given the cross-sectional design of the studies, and the presence of potential confounders and several forms of biases. Available studies also report contradictory findings. Further studies are recommended using prospective designs, standardized and valid measures of khat use, and focusing on specific types of mental health disorders.

An updated review on synthetic cathinones

Cathinone, the main psychoactive compound found in the plant Catha edulis Forsk. (khat), is a β-keto analogue of amphetamine, sharing not only the phenethylamine structure, but also the amphetamine-like stimulant effects. Synthetic cathinones are derivatives of the naturally occurring cathinone that largely entered the recreational drug market at the end of 2000s. The former "legal status", impressive marketing strategies and their commercial availability, either in the so-called "smartshops" or via the Internet, prompted their large spread, contributing to their increasing popularity in the following years. As their popularity increased, the risks posed for public health became clear, with several reports of intoxications and deaths involving these substances appearing both in the social media and scientific literature. The regulatory measures introduced thereafter to halt these trending drugs of abuse have proved to be of low impact, as a continuous emergence of new non-controlled derivatives keep appearing to replace those prohibited. Users resort to synthetic cathinones due to their psychostimulant properties but are often unaware of the dangers they may incur when using these substances. Therefore, studies aimed at unveiling the pharmacological and toxicological properties of these substances are imperative, as they will provide increased expertise to the clinicians that face this problem on a daily basis. The present work provides a comprehensive review on history and legal status, chemistry, pharmacokinetics, pharmacodynamics, adverse effects and lethality in humans, as well as on the current knowledge of the neurotoxic mechanisms of synthetic cathinones.

A Systematic Review of Treatments for Problematic Khat Use

Khat, a psychostimulant cultivated and commonly used in Eastern Africa and the Arabian penin-sula, has a longstanding history of use embedded within the cultures of these regions. Due to changing patterns of use and the adverse effects of dependence, khat has become a growing pub- lic health concern. Despite extensive findings regarding the detrimental psychiatric, physical, and social consequences of khat dependence, research on interventions in this area is glaringly sparse. The present paper aims to summarize the consequences of chronic khat use and review existing research on interventions.