The pharmacology of khat

Comparative Assessment of the Addictive Potential of Synthetic Cathinones by Zebrafish Conditioned Place Preference (CPP) Paradigm

Synthetic cathinones have gained increasing popularity in the illicit drug market, yet their abuse potential remains poorly understood. In this study, zebrafish were used to compare the addictive potential of three cathinone analogs, namely pentylone, eutylone, and N-ethylpentylone (NEP). The zebrafish received various doses (0 to 60 mg/kg) of the cathinone analogs by oral gavage over two sessions per day for two consecutive days to induce conditioned place preference (CPP). Pentylone, eutylone, and NEP dose-dependently induced CPP, with NEP showing significantly higher CPP than pentylone and eutylone at the dose of 20 mg/kg. The fish that received 60 mg/kg of cathinones underwent extinction, followed by reinstatement triggered by drug priming. NEP required six sessions to meet the criteria of extinction, followed by eutylone, which required four sessions, and pentylone, which required three sessions. Furthermore, NEP and eutylone at a dose of 40 mg/kg could reinstate the extinguished CPP, while 60 mg/kg of pentylone was necessary for CPP reinstatement. The persistence of susceptibility to reinstatement was also assessed at 7 and 14 days after the initial reinstatement. The CPP induced by all three cathinone analogs could be reinstated 7 days after the initial reinstatement, whereas only CPP induced by NEP, but not pentylone and eutylone, could be reinstated again after 14 days. Considering the potency to induce CPP, resistance to extinction, and the propensity for reinstatement, the abuse liability rank order of the cathinone analogs might be as follows: NEP > eutylone > pentylone. These findings suggest that the zebrafish CPP paradigm can serve as a viable model for assessing the relative abuse liability of substances.

Epidemiology of Khat (Catha edulis) Chewing in Ethiopia: A Systematic Review and meta-analysis

In several countries, including Ethiopia, the shrub Catha edulis (khat) leaves are chewed for their stimulant properties. The present review summarizes evidence on the prevalence of khat use in Ethiopia and forwards recommendations for future action. PubMed, Embase, and Scopus were searched for studies examining the prevalence of Khat chewing among adolescent and/or adult populations in Ethiopia. A random-effects model was employed to estimate the pooled prevalence of khat chewing. Of the 568 articles identified, 26 were included in the review. The pooled prevalence of current and lifetime khat use was 19.55% (95% CI 14.62-25.64) and 26.14% (CI 17.66-36.87), respectively. The current prevalence of khat use was higher in men, 23.72% (CI 13.42-38.41), than in women 8.45% (CI 4.94-14.08). Lifetime prevalence of khat use was higher in men, 29.8% (CI: 22.80-37.99) than in women 13.02% (CI 8.96-18.56). The results of the meta-analysis demonstrated a higher odds of current (OR = 4.00, CI 2.80-5.73) and lifetime (OR = 2.84, CI 2.50-3.23) khat use in men than in women. Our review found a high prevalence of current (19.55%) and lifetime (26.14%) khat chewing in Ethiopia and demonstrated higher odds of current and lifetime khat use in men than in women. Awareness creation and integrated management of khat use problems at the primary health-care level is highly recommended.

Exploring the perception of key stakeholders toward khat policy approaches in Ethiopia: a qualitative study

BACKGROUND

Khat is an amphetamine-like plant, produced and commonly chewed in Ethiopia by a large group of the population. Although significant multidimensional harms of khat use have been reported, currently, there are no policies or organized activities against khat use in Ethiopia. Therefore, the current study aimed to explore the perception of key stakeholders toward khat policy approaches for Ethiopia.

METHODS

A qualitative study was conducted using focus group discussion (FGD) and in-depth interview (IDI). Ten stakeholders participated in the IDIs, and another 15 individuals participated in the FGDs. Key stakeholders were appropriately mapped and purposively selected based on their experience related to khat use and khat harm reduction. Interviews and FGDs were led by the study authors and were audio-recorded. The audio-recorded data were transcribed verbatim and then translated into English language. The data were analyzed using thematic analysis approach.

RESULTS

Participants preferred prevention and law regulation measures for khat policy approaches for Ethiopia. Proposed prevention and law regulation measures included regulating the transportation of khat, limiting the minimum age to buy and sell khat, prohibiting khat use at some public places, banning khat advertising and promotion, and imposing excise tax. Individual level khat harm reduction strategies were also proposed to be useful. However, the participants asserted that total khat ban in Ethiopia is not likely to be feasible and acceptable.

CONCLUSION

Prevention, treatment or care for individuals with problematic khat use, law regulation, and harm reduction were preferred approaches by stakeholders for khat policy in Ethiopia instead of total banning.

Validation of the Problematic Khat Use Screening Test: A Cross-Sectional Study

AIM

The study aimed to evaluate the psychometric properties of the Problematic Khat Use Screening Test (PKUST-17) in Ethiopia.

METHODS

A validation study of PKUST-17 was carried out among 510 khat users, using a house-to-house survey. Confirmatory factor analysis and 2-parametric item response theory (IRT) were used to evaluate the construct validity of PKUST-17. We also used Spearman's rank-order correlation coefficient and other test statistics to assess the convergent validity of PKUST-17 with depression symptoms, functional impairment, and other characteristics of participants. We generated latent classes of problematic khat use using latent profile analysis (LPA) and validated the classes using multinomial logistic regression.

RESULTS

The data confirm the unidimensional model of the PKUST-17. The internal consistency of PKUST-17 was excellent (Cronbach's alpha = 0.93). IRT discrimination parameters indicated that each item had a strong ability to distinguish participants across the spectrum of problematic khat use (α thresholds range from 1.02 to 2.9). The items were fairly or moderately severe to be endorsed by participants (β thresholds vary from 1.43 to 5.57). The LPA identified three latent classes which have severity differences: mild (34%), moderate (34%), and severe (32%) problematic khat use. Depression symptoms, functional impairment, and other khat use patterns were also associated with moderate and severe problematic khat use class membership compared to mild problematic khat use class.

CONCLUSION

We found that the PKUST-17 is a culturally appropriate, brief, easy to use, and psychometrically sound screening test. PKUST-17 can be used to screen khat users with different levels of risk for providing stepped care at different healthcare levels, including integration of services in primary care. Future studies need to test the predictive capacity of the PKUST-17 for khat-related harms.

Khat (Catha Edulis Forsk) induced apoptosis and cytotoxicity in cultured cells: A scoping review

Background

Khat (Catha edulis Forsk) leaves are chewed by people in certain regions of East Africa and the Middle East for their stimulating amphetamine-like effects. The purpose of this scoping review is to systematically map the current in vitro publications that investigated the toxicological potential effects of khat on cultured human or animal cells in terms of cellular viability and activity.

Methods

A comprehensive electronic database search was undertaken up to December 2020 without starting date or language restrictions in accordance with the PRISMA extension for scoping review guideline and methodological quality evaluation based on the guidelines for reporting pre-clinical in vitro studies on dental materials. All in vitro studies that investigated the effect of khat plant extract (Catha Edulis) on the cultured human or animal cells were included.

Results

The initial search yielded 599 articles and 16 articles were finally selected to be included. The treatment of cells with khat produced different degrees of cellular changes, including decreased cellular survival, induction of apoptosis, increased ROS production, alteration of cell phenotype, and of arrest cell cycle. In this contest, khat-exposed cells expressed higher levels of pro-apoptotic protein Bax and lower levels of anti-apoptotic Bcl-2, up-regulated p38, p53, p16, and p21 proteins, as well as premature expression of differentiation markers.

Conclusion

Based on the current scoping review, khat induced apoptosis and cytotoxicity in cultured human cells, including oral cells.

In vitro effects of 95% khat ethanol extract (KEE) on human recombinant cytochrome P450 (CYP)1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5

OBJECTIVES

Khat, a natural amphetamine-like psychostimulant plant, are widely consumed globally. Concurrent intake of khat and xenobiotics may lead to herb-drug interactions and adverse drug reactions (ADRs). This study is a continuation of our previous study, targeted to evaluate the in vitro inhibitory effects of khat ethanol extract (KEE) on human cytochrome (CYP) 1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2, and CYP3A5, major human drug metabolizing enzymes.

METHODS

In vitro fluorescence enzyme assays were employed to assess CYPs inhibition with the presence and absence of various KEE concentrations.

RESULTS

KEE reversibly inhibited CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 but not CYP1A2 with IC₅₀ values of 25.5, 99, 4.5, 21, 27, 17, and 10 μg/mL respectively. No irreversible inhibition of KEE on all the eight CYPs were identified. The K_i values of CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 were 20.9, 85, 4.8, 18.3, 59.3, 3, and 21.7 μg/mL, respectively. KEE inhibited CYP2B6 via competitive or mixed inhibition; CYP2E1 via un-competitive or mixed inhibition; while CYP2A6, CYP2C8, CYP2C19, CYP2J2 and CYP3A5 via non-competitive or mixed inhibition.

CONCLUSIONS

Caution should be taken by khat users who are on medications metabolized by CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2, and CYP3A5.

Qualitative ultrastructural analysis of the submandibular salivary glands after administration of khat: in vivo study

Objective

Khat (Catha edulis Forssk) plant has been widely chewed for its psychostimulatory effects in the African and Arabian Peninsula, particularly in Yemen. Considering the khat leaves are gradually chewed without swallowing, while its active constituents are extracted into saliva, studying the effect of khat on salivary glands is necessary. This work is an extension of the previously published work that studied the effect of khat extract on the rats' submandibular salivary glands in terms of histological and immunohistochemical evaluations. The current research note aimed to better understand this effect on the ultrastructure of submandibular salivary gland cells by using transmission electron microscope.

Results

Oral administration of khat extract produced degenerative changes in the secretory and ductal cells of rats' submandibular salivary glands. These changes involved irregular boundaries of variable sized-nuclei, dilated RER, cytoplasmic vacuoles as well as swollen and degenerated mitochondria.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05595-8.

Para-Halogenation of Amphetamine and Methcathinone Increases the Mitochondrial Toxicity in Undifferentiated and Differentiated SH-SY5Y Cells

Halogenation of amphetamines and methcathinones has become a common method to obtain novel psychoactive substances (NPS) also called “legal highs”. The para-halogenated derivatives of amphetamine and methcathinone are available over the internet and have entered the illicit drug market but studies on their potential neurotoxic effects are rare. The primary aim of this study was to explore the neurotoxicity of amphetamine, methcathinone and their para-halogenated derivatives 4-fluoroamphetamine (4-FA), 4-chloroamphetamine (PCA), 4-fluoromethcathinone (4-FMC), and 4-chloromethcathinone (4-CMC) in undifferentiated and differentiated SH-SY5Y cells. We found that 4-FA, PCA, and 4-CMC were cytotoxic (decrease in cellular ATP and plasma membrane damage) for both cell types, whereby differentiated cells were less sensitive. IC₅₀ values for cellular ATP depletion were in the range of 1.4 mM for 4-FA, 0.4 mM for PCA and 1.4 mM for 4-CMC. The rank of cytotoxicity observed for the para-substituents was chloride > fluoride > hydrogen for both amphetamines and cathinones. Each of 4-FA, PCA and 4-CMC decreased the mitochondrial membrane potential in both cell types, and PCA and 4-CMC impaired the function of the electron transport chain of mitochondria in SH-SY5Y cells. 4-FA, PCA, and 4-CMC increased the ROS level and PCA and 4-CMC induced apoptosis by the endogenous pathway. In conclusion, para-halogenation of amphetamine and methcathinone increases their neurotoxic properties due to the impairment of mitochondrial function and induction of apoptosis. Although the cytotoxic concentrations were higher than those needed for pharmacological activity, the current findings may be important regarding the uncontrolled recreational use of these compounds.

Synthetic cathinone adulteration of illegal drugs

RATIONALE

Current prevalence estimates of synthetic cathinone ("bath salt") use may be underestimates given that traditional metrics (e.g., surveys, urinalysis) often fail to capture the emergent issue of synthetic cathinone adulteration of more common illegal drugs, such as ecstasy (3,4-methylenedioxymethamphetamine).

OBJECTIVES

This review examines the evolution of synthetic cathinones and prevalence of use over the past decade in the United States. We also review methods of self-report and biological testing of these compounds as well as adverse outcomes associated with adulterated drug use.

RESULTS

Synthetic cathinone use emerged in the United States by 2009 with use associated with tens of thousands of poisonings. Reported poisonings and self-reported use have substantially decreased over the past five years. However, our review suggests that current estimates of use are underestimates due to underreporting stemming primarily from unknown or unintentional use of adulterated formulations of relatively popular illegal drugs, such as ecstasy.

CONCLUSIONS

While intentional synthetic cathinone use has decreased in recent years, evidence suggests that prevalence of use is underestimated. Testing of drugs and/or biological specimens can improve the accuracy of synthetic cathinone use estimates. Furthermore, we advocate that researchers and clinicians should become better aware that exposure to these potent compounds (e.g., as adulterants) often occurs unknowingly or unintentionally. To improve our understanding of synthetic cathinone adulteration, research utilizing a combinatorial approach (survey and biological testing) will help more accurately estimate the prevalence and impact of this public health issue.

Epidemiology of khat (Catha edulis) consumption among university students: a meta-analysis

BACKGROUND

Khat is amphetamine-like substance commonly consumed by students when they wish to study for long hours especially during examination periods. Khat consumption is associated with increased rates of cardiovascular problems, stroke, myocardial infarction, cardiomyopathy, periodontal disease, gastritis, poor oral hygiene, psychosis, decreased quality of life, and poor academic performance.

METHODS

PubMed, EMBASE, and SCOPUS were systematically searched without restriction by publication status. Publications were screened according to predefined inclusion criteria. Twenty-five articles were included. Random effect model was used to calculate weighted prevalence, odds ratio (OR) and corresponding 95% confidence interval (CI). We assessed the risk of publication bias by using funnel plot and Eggers's regression tests.

RESULTS

The pooled prevalence of current khat use among university students was 14.16% (95% CI; 11.87-16.81). The pooled prevalence of current khat use was highest in Saudi Arabia 18.85% and it was 13.59% in Ethiopia and 13.04% in Yemen. In addition, the current pooled prevalence of khat use was higher in men at 19.26% than in women 6.41%. Regarding lifetime khat use, in this study, the pooled prevalence of lifetime khat use was 27.31%. The lifetime prevalence was higher in men at 31.47% than in women 11.79%. Moreover, the lifetime prevalence of khat use was 43.27% in Yemen, 37.32% in Saudi Arabia, and 24.82% in Ethiopia. We found significantly increased odds of current (OR 3.59; 95%CI 2.01-6.41) as well as lifetime (OR 3.48; 95%CI 2.09-5.78) khat chewing in men as compared to women.

CONCLUSION

The pooled prevalence of current and lifetime khat consumption was 14.16 and 27.31%, respectively. Both the current and lifetime prevalence of khat use was higher in men than in women. In addition, both the current and lifetime prevalence estimates of khat consumption were low in Ethiopia than in Saudi Arabia. Moreover, the odds of both current and lifetime khat consumption were higher in male students than in female students. Programmes that specifically aim at increasing awareness and that most motivate reduced khat consumption among university students were recommended.

Prevalence and predictors of khat chewing among Ethiopian university students: A systematic review and meta-analysis

Background

Khat chewing has become a common practice among university students in developing countries like Ethiopia. It has a potential effect on physical, mental, social and cognitive aspects of student functioning. In Ethiopia, study findings regarding the prevalence of khat chewing were highly dispersed and inconsistent. Therefore, this systematic review and meta-analysis estimates the pooled prevalence of khat chewing and its predictors among Ethiopian university students.

Method

A systematic review and meta-analysis was conducted to assess the prevalence and predictors of khat chewing among university students in Ethiopia. We searched literature from the databases of PubMed, Google Scholar, Science Direct, and the Cochrane Library. A total of 24 Ethiopian studies reporting the prevalence of khat chewing among university students were included. Data were extracted using a standardized data extraction format prepared in Microsoft Excel and the analysis was done using STATA 14 statistical software. To assess heterogeneity, the Cochrane Q test statistics and I² test were used. Since the included studies exhibit high heterogeneity, a random effect meta-analysis model was computed to estimate the pooled prevalence of khat chewing. Moreover, the association between predictor variables, and khat chewing practice were examined.

Results

The meta-analysis of 24 studies revealed that the pooled prevalence of khat chewing among university students in Ethiopia was 23.22% (95% CI: 19.5, 27.0). In the subgroup analysis, the highest prevalence was observed in Oromia region (31.6%; 95CI: 21.2, 41.9) whereas the lowest prevalence was observed in Amhara region (18.1%; 95%CI: 12.4, 23.8). Being male OR: 2.76 (95% CI 1.64, 4.63), family khat chewing practice OR: 2.91 (95% CI 1.06, 7.98), friend khat chewing habit OR: 4.74 (95% CI 3.48, 13.06), alcohol drinking OR: 7.06 (95% CI 5.65, 8.82) and cigarette smoking habit OR: 15.11 (95% CI 8.96, 25.51) were found to be predictors of khat chewing.

Conclusion

The study found that the prevalence of khat chewing among university students was quite common, with slightly more than 1 in 5 students engaging in the use of this substance. Being male, family khat chewing practice, friend’s khat chewing habit, alcohol drinking, and cigarette smoking were found to be predictors of khat chewing practice among university students.

Adverse effects of khat: a review

Catha edulis (khat) is a plant grown in the countries around the Red Sea and on the eastern coast of Africa. Its leaves are chewed by the local people for their stimulant action. Its principal active constituents are cathinone and cathine, which have sympathomimetic actions. Migration of Africans from these countries has spread the habit of khat chewing to the West. Chewing khat has a number of important psychological and physical sequelae. ‘Khat-related’ psychosis is very similar to that seen following use of amphetamines.

Qat use and esophageal cancer in Ethiopia: A pilot case-control study

BACKGROUND

Qat (Catha edulis) chewing is reported to induce lesions in the buccal mucosa, irritation of the esophagus, and esophageal reflux. Case series suggest a possible etiological role in oral and esophageal cancers. This pilot study aimed to generate preliminary estimates of the magnitude and direction of the association between qat use and esophageal cancer (EC) risk and to inform the logistics required to conduct a multi-center case-control study.

METHODS

Between May 2012 and May 2013, 73 EC cases (including 12 gastro-esophageal junction cases) and 133 controls matched individually on sex, age, and residence were enrolled at two endoscopy clinics and a cancer treatment hospital in Addis Ababa. A face-to-face structured questionnaire was administered. Qat use was defined as ever having chewed qat once a week or more frequently for at least one year. Odds ratios were calculated using conditional logistic regression.

RESULTS

Only 8% of cases resided in Addis Ababa. Qat use was more frequent in cases (36%) than in controls (26%). A 2-fold elevation in EC risk was observed in ever qat chewers compared with never users in unadjusted conditional logistic regression (OR = 2.12; 95% CI = 0.94, 4.74), an association that disappeared after adjusting for differences in tobacco use, consumption of alcohol and green vegetables, education level, and religion (OR = 0.95; 0.22, 4.22). Among never tobacco users, however, a non-significant increase in EC risk was suggested in ever qat users also after adjustment. Increases in EC risk were observed with ever tobacco use, alcohol consumption, low consumption of green vegetables, a salty diet, illiteracy, and among Muslims; the four latter associations were significant.

CONCLUSIONS

This pilot study generated EC risk estimates in association with a habit practiced by millions of people and never before studied in a case-control design. Results must be interpreted cautiously in light of possible selection bias, with some demographics such as education level and religion differing between cases and controls. A large case-control study with enrolment of EC cases and carefully matched controls at health facilities from high-risk areas in the countryside, where the majority of cases occur, is needed to further investigate the association between qat use and EC.

What constitutes problematic khat use? An exploratory mixed methods study in Ethiopia

Background

Khat is a psycho-stimulant herb, which has been in use in traditional societies in East Africa and the Middle East over many centuries. Although khat is reported to cause various health problems, what constitutes problematic khat use has never been systematically investigated. This study explored the acceptable and problematic uses of khat from the perspective of users.

Methods

The study used a mixed methods design (exploratory sequential) in which qualitative (emic) data were collected to develop a framework to define problematic khat use. The qualitative data were gathered through in-depth interviews (N = 13) and focus group discussions (N = 34). By supplementing the emic experiences considered to constitute problematic khat use with an etic definition, DSM-5 criteria for stimulant related disorders, a structured questionnaire was developed. Subsequently a cross-sectional evaluation of 102 respondents was carried out. Respondents both for qualitative and quantitative study were selected through purposive sampling and snowballing methods. Qualitative data were transcribed and subjected to thematic analysis whereas quantitative data were analyzed using descriptive and nonparametric statistics.

Results

Khat use was acceptable socio-culturally and for functional purposes. However, even in these acceptable contexts there was a restriction to the amount, frequency and type of khat used, and in relation to the experience of the individual using khat and other personal characteristics. More specifically, khat use was considered problematic if there was: 1) Impairment (in social and occupational functioning); 2) loss of control in the use of khat; and 3) withdrawal symptoms when not using khat. Among the participants who use khat (n = 102), 45.1% (n = 46) used khat on a daily basis. The commonest indicators of problematic khat use endorsed by the khat users were loss of control over chewing (73.5%), continuing use of khat despite harm (72.5%) and efforts to avoid withdrawal from khat (61.8%).

Conclusion

Despite reported religious, sociocultural and functional benefits to the use of khat, those with defined problematic khat use have impaired mental health, and social and occupational performance. Comparison of these respondent defined indicators of problem behavior matched almost completely to the DSM-5 (etic-defined) understanding of problematic stimulant use. Although the findings have relevant clinical, research and policy implications, the study focused on users purposively identified. Future larger scale definitive studies are required to make concrete policy recommendations.

Khat - a new precipitating factor for reversible cerebral vasoconstriction syndrome: a case report

BACKGROUND

Postpartum reversible cerebral vasoconstriction syndrome is one of the rare reversible cerebral vasoconstriction syndromes. The clinical presentation is usually characterized by recurrent headache, focal neurological deficit, and reversible cerebral vasoconstriction seen on cerebral angiography.

CASE PRESENTATION

We report a case of a 35-year-old Yemeni woman who presented with headache and focal neurological deficits that occurred 10 days after delivery, with segmental narrowing of cerebral arteries on angiography. She had significant clinical and radiological improvement on follow-up.

CONCLUSIONS

The presentation of our patient's reversible cerebral vasoconstriction syndrome is unusual as she has two possible precipitating factors. In addition to being in the postpartum state, she also has a long history of chewing khat, a vasoactive substance commonly used by immigrants from Yemen. We hope that this case report will increase awareness among physicians about the use of this plant by immigrants from the horn of Africa and Yemen.

Effect of Habitual Khat Chewing on Glycemic Control, Body Mass Index, and Age at Diagnosis of Diabetes in Patients with Type 2 Diabetes Mellitus in Yemen

Khat chewing is common in Yemen. We conducted this study to see if it affected diabetes control in patients with type 2 diabetes mellitus (DM). We studied 1540 patients with type 2 DM attending an endocrinology clinic in Sana’a, Yemen, of which 997 were khat chewers (KC) and 543 were non-khat chewers (NKC). The patients answered a questionnaire regarding khat chewing. Hemoglobin A1c (HbA1c) and body mass index (BMI) were measured. KC had a higher mean HbA1c of 9.8 (95% confidence interval (95% CI) 9.6–10) than the NKC, with a mean of 9.1 (95% CI 8.9–9.4) (adjusted odds ratios (AOR) 1.74, P < 0.001) after multivariate regression analysis. KC also had a lower mean BMI, 26.9 (95% CI 26.6–27.2), than the NKC, mean BMI 27.6 (95% CI 27.1–28) (P < 0.01). The mean age at diagnosis of DM among the KC group was 43.3 (10.1) and among the NKC group was 45.9 (11.8) (AOR 1.4 P < 0.008) after multivariate regression analysis. KC patients had a higher mean HbA1c, a lower BMI, and a younger age at diagnosis of type 2 DM when compared with NKC.

Khat use: history and heart failure

Recent reports suggest that 20 million people worldwide are regularly using khat as a stimulant, even though the habit of chewing khat is known to cause serious health issues. Historical evidence suggests khat use has existed since the 13th century in Ethiopia and the southwestern Arabian regions even before the cultivation and use of coffee. In the past three decades, its availability and use spread all over the world including the United States and Europe. Most of the consumers in the Western world are immigrant groups from Eastern Africa or the Middle East. The global transport and availability of khat has been enhanced by the development of synthetic forms of its active component. The World Health Organization considers khat a drug of abuse since it causes a range of health problems. However, it remains lawful in some countries. Khat use has long been a part of Yemeni culture and is used in virtually every social occasion. The main component of khat is cathinone, which is structurally and functionally similar to amphetamine and cocaine. Several studies have demonstrated that khat chewing has unfavorable cardiovascular effects. The effect on the myocardium could be explained by its effect on the heart rate, blood pressure, its vasomotor effect on the coronary vessels, and its amphetamine-like effects. However, its direct effect on the myocardium needs further elaboration. To date, there are few articles that contribute death among khat chewers to khat-induced heart failure. Further studies are needed to address the risk factors in khat chewers that may explain khat-induced cardiotoxicity, cardiomyopathy, and heart failure.

Catha edulis chewing effects on treatment of paranoid schizophrenic patients

BACKGROUND

The current study's aim is to evaluate the possible interaction effects of khat chewing on treatment of paranoid schizophrenic patients.

PATIENTS AND METHODS

In the study group, 42 male subjects suffered from paranoid schizophrenia and were classified according to their khat chewing habits into two subgroups: either khat-chewer subgroup (SKc; n=21; r=11, h=10) or non-khat-chewer subgroup (SNKc; n=21, r=11, h=10). Each subgroup was further subdivided according to type of treatment into r (risperidone) and h (haloperidol). Healthy male subjects (37) were subdivided into healthy khat-chewer as positive controls (HKc, n=17) and healthy non-khat-chewer as negative controls (HNKc, n=20). Plasma dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid, 5-hydroxytryptamine (serotonin), 5-hydroxyindoleacetic acid, epinephrine, and norepinephrine were estimated.

RESULTS

ANOVA and post hoc analysis showed that dopamine was illustrating significant elevation in all khat chewing groups. DOPAC was illustrating significant decrease in all khat chewing groups with an interesting outcome showing significant increase in DOPAC in SNKcr group due to risperidone effect. Homovanillic acid, serotonin, hydroxyindoleacetic acid, and norepinephrine were illustrating significant elevations in all khat chewing groups. Epinephrine was illustrating significant elevation in all chewers than non-chewers groups. Unexpected significant decrease in epinephrine in the SNKcr group indicated that risperidone drug is decreasing epinephrine through indirect mechanism involving calcium.

CONCLUSION

Khat chewing in schizophrenic patients is contraindicated because it aggravates the disease symptoms, attenuates all used treatment medications, and deteriorates all biochemical markers of the patients.

Epicardial coronary arteries in khat chewers presenting with myocardial infarction

Background. Khat chewing is a common habit in Yemen despite increased evidence of its negative impact on the cardiovascular system. Aims. We aimed to study the epicardial coronary arteries in khat chewers presenting with myocardial infarction (AMI). Materials and Methods. A descriptive, cross-sectional study was conducted between November 2008 and May 2009 in Yemen. AMI patients who underwent coronary angiogram were enrolled and divided into groups (gp): gp1 (diabetic and khat chewers), gp2 (khat chewers and nondiabetic), and gp3 (diabetic and non-khat users). Results. Of 347 AMI patients 63%, 21%, and 16% were in gp 2, 3, and 1, respectively. Khat chewers were younger in comparison to non-khat users. Group 3 patients were more likely to have multivessel disease, severe left anterior descending (LAD), right coronary artery (RCA) stenosis and total RCA, and left circumflex (Lcx) occlusion compared to other groups. Group 1 patients were more likely to have total LAD occlusion and severe Lcx lesions. In multivariate analysis, age, diabetes mellitus, and smoking were significant independent predictors for significant coronary artery lesions; however, khat chewing did not show such association. Conclusions. Coronary spasm is the main mechanism of AMI in khat chewers. The impact of our finding for risk stratification and management warrants further studies.

Association of socioeconomic and behavioral factors with adult mortality: analysis of data from verbal autopsy in Addis Ababa, Ethiopia

BACKGROUND

Changes in socioeconomic status, lifestyle and behavioral factors among the urban population in Ethiopia is resulting in a shift in the causes of mortality.We used verbal autopsy data from 2006 to 2009 to measure the association of socioeconomic and behavioral factors with causes of mortality in Addis Ababa, Ethiopia.

METHODS

A total of 49,309 deaths from burial surveillance were eligible for verbal autopsy for the years 2006 to 2009. Among these, 10% (4,931) were drawn randomly for verbal autopsy of which 91% (4,494) were adults of age≥15 years. Verbal autopsies, used to identify causes of death and frequency of risk factors, were completed for 3,709 (83%) of the drawn sample.

RESULTS

According to the results of the verbal autopsy, non-communicable diseases caused 1,915 (51%) of the total adult deaths, while communicable diseases and injuries caused 1,566 (42%) and 233 (6%) of the deaths respectively.Overall, frequent alcohol (12%) and tobacco consumption (7%) were highly prevalent among the deceased individuals; both because of communicable diseases (HIV/AIDS and tuberculosis) as well as due to non-communicable diseases (malignancy, cardiovascular and chronic liver diseases). HIV/AIDS (AOR=2.14, 95% CI [1.52-3.00], p<0.001) and chronic liver diseases (AOR=3.09, 95% CI [1.95-4.89], p<0.001) were significantly associated with frequent alcohol consumption, while tuberculosis was associated with both frequent alcohol (AOR=1.61, 95% CI [1.15-2.24], p=0.005) and tobacco consumption (AOR=1.67, 95% CI [1.13-2.47], p<0.010). Having low educational status, being female and being within the age range of 25 to 44 years were positively associated with HIV/AIDS related mortality. Individuals aged 45 years and above were 3 to 6 times more likely to have died due to cardiovascular diseases compared with those within the 15 to 24 years age group.

CONCLUSION

The findings from the analysis suggest that public health interventions targeting HIV/AIDS, tuberculosis, as well as non-communicable diseases need to consider behavioral factors related to alcohol, tobacco and khat consumption. We also recommend large scale national level studies to further assess the specific contributions of these risk factors to the burden of mortality in the country.

Mephedrone and methylenedioxypyrovalerone (MDPV), major constituents of "bath salts," produce opposite effects at the human dopamine transporter

RATIONALE

Psychoactive "bath salts" represent a relatively new drug of abuse combination that was placed in Schedule I in October 2011. Two common ingredients of bath salts include the cathinone analogs: mephedrone and methylenedioxypyrovalerone (MDPV). The mechanism of action of these synthetic cathinone analogs has not been well investigated.

MATERIALS AND METHODS

Because cathinone and methcathinone are known to act as releasing agents at the human dopamine transporter (hDAT), mephedrone and MDPV were investigated at hDAT expressed in Xenopus oocytes.

RESULTS

Whereas mephedrone was found to have the signature of a dopamine-releasing agent similar to methamphetamine or methcathinone, MDPV behaved as a cocaine-like reuptake inhibitor of dopamine.

CONCLUSIONS

Mephedrone and MDPV produce opposite electrophysiological signatures through hDAT expressed in oocytes. Implications are that the combination (as found in bath salts) might produce effects similar to a combination of methamphetamine and cocaine.

Khat chewing and cardiovascular risk profile in a cohort of Yemeni patients with angiographically documented coronary artery disease

OBJECTIVE

We sought to explore the prevalence of khat chewing and cardiovascular risk profile in a cohort of Yemeni patients with angiographically documented coronary artery disease (CAD).

METHODS

We enrolled 100 consecutive Yemeni patients who underwent elective coronary catheterisation. Patients were considered eligible for enrolment if they had angiographically documented significant CAD (>50% obstruction). History of khat chewing was obtained and recorded at the time of presentation. Coronary angiography was performed using the standard technique. Reference vessel diameter and the per cent diameter stenosis were measured using quantitative coronary analysis. Patients were classified according to the number of sizable coronary arteries affected by significant stenosis into three groups: single-vessel disease, two-vessel disease and multi-vessel disease groups.

RESULTS

The mean age was 54.7±11.8 years (16% females); 86% were khat users, 46% had single-vessel disease, 36% had two-vessel disease and 18% had multi-vessel disease. Fifty-four per cent were smokers, 11% were diabetic and 15% were hypertensive. The mean body mass index was 24.7±3.6, the mean serum low-density lipoprotein cholesterol was 129±41 mg/dl, whereas the mean serum triglyceride level was 187±90 mg/dl; the mean serum high-density lipoprotein cholesterol was 38±11 mg/dl. No correlation was found between the extent of CAD and any of the clinical, echocardiographic or laboratory data.

CONCLUSIONS

In Yemeni patients undergoing elective coronary angiography, khat use was highly prevalent, whereas several classic risk factors were relatively infrequent. None of the risk factors or khat use differed substantially with the extent of CAD.

Toxicological Features of Catha edulis (Khat) on Livers and Kidneys of Male and Female Sprague-Dawley Rats: A Subchronic Study

Hepato- and nephrotoxicity of Khat consumption (Catha edulis Forskal) have been evoked. Therefore, this study was conducted to evaluate such possible hepatorenal toxicity in female and male Sprague-Dawley rats (SD rats) focusing primarily on liver and kidney. In addition, female and male rats were investigated separately. Accordingly, forty-eight SD-rats (100–120 g) were distributed randomly into four groups of males and female (n = 12). Normal controls (NCs) received distilled water, whereas test groups received 500 mg/kg (low dose (LD)), 1000 mg/kg (medium dose (MD)), or 2000 mg/kg (high dose (HD)) of crude extract of Catha edulis orally for 4 weeks. Then, physical, biochemical, hematological, and histological parameters were analyzed. Results in Khat-fed rats showed hepatic enlargement, abnormal findings in serum aspartate aminotransferase (AST), and alkaline phosphatase (ALP) of male and female SD-rats and serum albumin (A) and serum creatinine (Cr) of female as compared to controls. In addition, histopathological abnormalities confirmed hepatic and renal toxicities of Khat that were related to heavy Khat consumption. In summary, Khat could be associated with hepatic hypertrophy and hepatotoxicity in male and female SD-rats and nephrotoxicity only in female SD-rats.

Acute exposure to Catha edulis depresses contractility and induces myocardial infarction in spontaneously contracting, isolated rabbit's heart

Khat chewing is a recreational habit known to pose major socio-economic and medical problems in countries of Southern Arabia and the Horn of Africa. Among other adverse health effects, khat chewing has been associated with an increased risk of myocardial infarction (MI) in heavy consumers. This study was carried out to examine the direct effects of Catha edulis extract on contractility of spontaneously contracting, isolated rabbit heart and to investigate its mechanism of action. Isolated six rabbit's hearts attached to a Langendorff apparatus were perfused with extract at a constant flow rate and continuously bubbled with a 95% O2/5% CO2 gas mixture. Each heart served as its own control, as responses were recorded before and after administration of C. edulis extract. Varying concentrations of extract (50, 100 and 250 mg/ml) were loaded in the perfusate, their effects recorded and effluent fluid collected for assay of cardiac enzymes. Histological examination of the cardiac tissue was performed at the end of perfusion with 250 mg/ml extract. This study revealed that acute exposure to C. edulis extract exerted negative inotropic and chronotropic effects on isolated hearts. The extract also had a vasoconstrictor effect on coronary vessels, independent of α1 adrenergic receptor stimulation. Histological examination of hearts perfused with 250 mg/ml C. edulis extract revealed the presence of histological changes unique to myocardial infarction, a finding consistent with observed increased levels of cardiac enzymes in perfusates. Thus, we have demonstrated experimentally a direct cardiac depressant- and MI inducing effects of C. edulis extract. These results are consistent with the earlier reported deleterious effects of khat on cardiovascular function among khat chewers.

Khat chewing in persons with severe mental illness in Ethiopia: a qualitative study exploring perspectives of patients and caregivers

People with severe mental illness (SMI) in Ethiopia chew khat despite advice from their physicians to desist. We wanted to better understand their reasons for khat chewing, including any benefits that they might gain. A qualitative study was conducted involving patients with SMI and their caregivers in Butajira. Reasons given by patients as well as caregivers were more or less congruent: social pressure, a means for survival by improving function, combating medication side effects, to experience pleasure and curbing appetite. These findings will be of value to health workers, caregivers and policymakers alike in improving care and understanding for this patient group. Furthermore, our study indicates a role for future research to explore potentially beneficial effects of khat in this population.

Khat chewing, cardiovascular diseases and other internal medical problems: the current situation and directions for future research

The leaves of khat (Catha edulis Forsk.) are chewed as a social habit for the central stimulant action of their cathinone content. This review summarizes the prevalence of the habit worldwide, the actions, uses, constituents and adverse health effects of khat chewing. There is growing concern about the health hazards of chronic khat chewing and this review concentrates on the adverse effects on health in the peripheral systems of the body, including the cardiovascular system and gastrointestinal tract. Comparisons are made with amphetamine and ecstasy in particular on the detrimental effects on the cardiovascular system. The underlying mechanisms of action of khat and its main constituent, cathinone, on the cardiovascular system are discussed. Links have been proposed between khat chewing and the incidence of myocardial infarction, dilated cardiomyopathy, vascular disease such as hypertension, cerebrovascular ischaemia and thromboembolism, diabetes, sexual dysfunction, duodenal ulcer and hepatitis. The evidence, however, is often based on limited numbers of case reports and only few prospective controlled studies have been undertaken. There is therefore an urgent need for more thorough case-control studies to be performed. This review outlines the current knowledge on the adverse health effects of khat chewing on the cardiovascular system and other internal medical problems, it assesses the evidence and the limitations of the studies and identifies the questions that future studies should address.

Association of khat chewing with increased risk of stroke and death in patients presenting with acute coronary syndrome

OBJECTIVE

To evaluate the prevalence and significance of khat chewing in patients with acute coronary syndrome (ACS).

PATIENTS AND METHODS

From January 29, 2007, through July 29, 2007, 8176 consecutive patients presenting with ACS were enrolled in a prospective, multicenter study from 6 adjacent Middle Eastern countries.

RESULTS

Of the 8176 study patients, 7242 (88.6%) were non-khat chewers, and 934 (11.4%) were khat chewers, mainly of Yemeni origin. Khat chewers were older (57 vs 56 years; P=.01) and more likely to be men (85.7% vs 74.5%) compared with non-khat chewers. Non-khat chewers were more likely to have diabetes mellitus, hypertension, dyslipidemia, obesity, and prior history of coronary artery disease and revascularization. Cigarette smoking was more prevalent in khat chewers, and they were more likely to present greater than 12 hours after onset of symptoms compared with non-khat chewers. At admission, khat chewers had higher heart rate, Killip class, and Global Registry of Acute Coronary Events risk scores. Khat chewers had a significantly higher risk of cardiogenic shock, stroke, and mortality. After adjustment of baseline variables, khat chewing was an independent risk factor for in-hospital mortality (odds ratio, 1.9; 95% confidence interval, 1.3-2.7; P<.001) and stroke (odds ratio, 2.7; 95% confidence interval, 1.3-5.9; P=.01).

CONCLUSION

In this large cohort of patients with ACS, khat chewing was prevalent and was associated with increased risk of stroke and death. In the context of increasing global migration, a greater awareness of potential widespread practices is essential.

Khat - a controversial plant

Khat (Catha edulis) is a shrub or tree whose leaves have been chewed for centuries by people who live in the Eastern part of Africa and the Arabian Peninsula. It has recently turned up in North America and Europe, particularly among emigrants and refugees from countries such as Somalia, Ethiopia and Yemen. Khat contains a number of chemicals, among which are two controlled substances, cathinone (Schedule I) and cathine (Schedule IV). Both chemicals are stimulant drugs with effects similar to amphetamine. Chewing the leaves makes people feel more alert and talkative, and suppresses appetite. Chewing khat leaves releases cathinone, a stimulant that produces the feeling of euphoria. When cathinone is broken down in the body, it produces chemicals including cathine and norephedrine, which have a similar structure to amphetamine and adrenaline (epinephrine). Regular khat use is associated with a rise in arterial blood pressure and pulse rate, corresponding with levels of cathinone in the plasma. Moreover, regular khat chewers have gingivitis and loose teeth, but there appears to be no convincing unusual incidence of oral cancer. Among khat users in Yemen there is, however, a higher incidence of esophageal cancer compared with gastric cancer. Long term use or abuse can cause insomnia, anorexia, gastric disorders, depression, liver damage and cardiac complications, including myocardial infarction. Manic and delusional behavior, violence, suicidal depression, hallucinations, paranoia and khat-induced psychosis have also been reported. On the basis of the scientific data it seems clear that khat use has negative consequences on the economic development of a country and on the health of the society.

Illicit cathinone (“Hagigat”) poisoning

INTRODUCTION

Khat leaves (mainly cathinone and cathine) have been chewed for centuries as stimulants. Hagigat (capsules of 200 mg cathinone) have been marketed in Israel as a natural stimulant and aphrodisiac. The consequences of illicit exposure to cathinone are reported.

METHODS

Prospective observational study of calls to the Poison Center regarding exposure to Hagigat during the course of 10 months. Demographic and clinical data were abstracted from patients' records and telephone follow up was performed.

RESULTS

Data of 34 consecutive patients aged 16-54 years were analyzed. The amount consumed was (1/2)-6 capsules (ingestion-32, sniffing-2). Main clinical manifestations were headache, vomiting, hypertension, nausea, tachycardia, dyspnea, chest pain, and myalgia. Main complications were myocardial ischemia (3), pulmonary edema (2), and intracerebral hemorrhage (1), all in young subjects. Treatment was supportive; one patient underwent neurosurgery.

CONCLUSION

Exposure to illicitly synthesized cathinone is associated with serious cardiovascular and neurological toxicity, even in young subjects.

Genotoxic effect of Catha edulis (khat) crude extract after sub-chronic administration in rats

The aim of this study was to evaluate the genotoxic effects of a crude extract of khat (Catha edulis, Forsk) leaves in rats. Two groups were fed khat crude extract, 1000 and 2000mg/kg body weight, for 90 days and were compared with a control group. The alkaline (pH>13) version of comet assay was used in this study. However, no previous published work has been undertaken and showed the effect of khat on DNA migration in the comet assay. To compare the comet assay results with another genetic endpoint, blood samples were analyzed for chromosomal aberrations. These results showed no DNA damage detected using comet assay in both the khat treated groups, while the results of chromosomal aberrations assay showed a significant increase (P<0.05) in the 2000mg/kg body weight treated group compared to the control group.

Khat (Catha edulis) lowers plasma luteinizing hormone (LH) and testosterone secretion, but increases cortisol levels in male rabbits

AIM

This study investigated the effects of fresh khat extract on specific circulating hormones in male rabbits.

MATERIALS AND METHODS

A total of 25 male New Zealand White rabbits were divided into five groups each comprising five animals. The first four groups were fed four doses (1.5 g/kg, 4.5 g/kg, 13.5 g/kg and 40.5 g/kg body weight) of khat extract twice a week for 5 weeks while the last group, serving as control, was fed only normal saline via intragastric tube. Blood samples were collected at 15 min interval for up to 3 h after khat extract administration and plasma assayed for luteinizing hormone (LH), testosterone and cortisol levels using radioimmunoassay technique.

RESULTS

Khat extract at all doses significantly lowered (P<0.05) LH pulse frequency, area under LH curve, mean plasma LH and mean plasma testosterone levels. Plasma cortisol levels were significantly elevated (P<0.05) in khat-treated rabbits in a dose-dependent manner.

CONCLUSION

This study demonstrates that khat may impair reproductive function in male rabbits by interfering with sex hormone profiles.

Vasoconstriction of porcine left anterior descending coronary artery by ecstasy and cathinone is not an indirect sympathomimetic effect

3,4-methylenedioxymethamphetamine ('Ecstasy', MDMA) and cathinone, the active constituent of khat leaves, were examined on pig isolated left anterior descending coronary arteries to determine whether they cause vasoconstriction and whether this was an indirect sympathomimetic action. Coronary artery rings were set up in Krebs solution (37 degrees C) gassed with 5% CO2 in O2. Endothelium remained intact as indicated by relaxation by bradykinin. Isometric tension was recorded and cumulative concentration-response curves (CRCs) for noradrenaline, ecstasy or cathinone plotted as a percent of the constriction to KCl (60 mM). Noradrenaline-induced contractions of the coronary artery were enhanced by propranolol (1 microM) indicating beta-adrenoceptor-mediated opposing vasodilatation. Cocaine (10 microM) further potentiated, while prazosin (1 microM) virtually abolished the contractions to noradrenaline. Cathinone and ecstasy constricted the coronary artery rings, the peak contractions being 56.5+/-4.2% (n=4) and 37.3+/-2.4% (n=4), respectively. Higher concentrations relaxed. The vasoconstriction was not affected by cocaine (10 microM), prazosin (1 microM, in the presence of cocaine) or removal of the endothelium. There was no tachyphylaxis or desensitisation on repeated administration of single doses. Ecstasy- and cathinone-induced coronary vasoconstriction is therefore via mechanisms other than indirect sympathomimetic activity or alpha1 -adrenoceptors. This activity could explain the cardiac adverse effects following their excessive use.

The potential adverse effects of habitual use of Catha edulis (khat)

The habit of Catha edulis Forsk (khat) chewing has prevailed for centuries among populations in the horn of Africa and the Arabian peninsula. Fresh leaves of Catha edulis are customarily chewed to attain a state of stimulation. The fact that cathinone has a closer structural similarity with amphetamine, and both share common pharmacodynamic features, led to the conclusion that cathinone is the most important active ingredient of Catha edulis, which causes the major pharmacological effects. Problems associated with repeated consumption of Catha edulis leaves are becoming evident. Literature surveys and clinical diagnostic studies revealed an association with prevalence of psychiatric morbidity. Repeated intermittent oral administration of Catha edulis to laboratory animals lead to development and expression of locomotor sensitisation. Catha edulis also leads to several peripheral effects that include increases in blood pressure and has been associated with the increased incidence of acute coronary vasospasm and myocardial infarction. Catha edulis also accounts for a number of gastrointestinal tract problems, oesophagitis, gastritis and delay intestinal absorption, as well as the development of oral keratotic white lesions at the site of chewing. Administration of Catha edulis extracts showed a deranged systemic capacity to handle oxidative radicals and induces cytotoxic effects in cells of liver and kidney, as well as induction of cell death in various human leukaemia cell lines and in peripheral human blood leukocytes.

Khat and alcohol use and risky sex behaviour among in-school and out-of-school youth in Ethiopia

Background

Khat (an evergreen plant with amphetamine-like properties) and alcohol are widely consumed among the youth of Ethiopia. However, their relationship to risky sexual behaviour is not well described. This study was conducted to describe the magnitude of risky sexual behaviour (unprotected sex and early initiation of sexual activity) and its association with Khat and alcohol consumption in Ethiopian youths.

Methods

A probabilistic national sample of 20,434 in-school and out-of-school youths aged between 15 and 24 years of age was selected and interviewed regarding their sexual behavior and substance use.

Results

Over 20% of out-of-school youth had unprotected sex during the 12-month period prior to interview compared to 1.4% of in-school youth. Daily Khat intake was also associated with unprotected sex: adjusted OR (95% CI) = 2.26 (1.92, 2.67). There was a significant and linear association between alcohol intake and unprotected sex, with those using alcohol daily having a three fold increased odds compared to those not using it: adj. OR (95% CI) = 3.05 (2.38, 3.91). Use of substances other than Khat was not associated with unprotected sex, but was associated with initiation of sexual activity: adj. OR (95% CI) = 2.54 (1.84, 3.51).

Conclusion

A substantial proportion of out-of-school youth engage in risky sex. The use of Khat and alcohol and other substances is significantly and independently associated with risky sexual behaviour among Ethiopian youths.

Methcathinone: A new postindustrial drug

Methcathinone, a methyl derivative of cathinone, is an illicit drug also known as ephedrone. It is a stimulant found in the "khat" plant, Catha edulis, which can easily be synthesized from pseudoephedrine. Its intoxication is difficult to diagnose and cure properly for two reasons: (i) target consumers are usually "well-educated people" aware of the risks and precautionary measures and (ii) intoxication by cathinone derivatives of synthetic or natural (derived from the khat) origin induce misleading symptoms. As a result, documented reports of methcathinone intoxication that are based on reliable analyses are rare. This paper describes a case of reiterated coma due to an overdose of methcathinone dissolved in alcohol that was taken with bromazepam. A 29-year-old woman was admitted to an emergency department for a coma of toxic origin. Medical files showed that it was her second such episode to occur that month. Moreover, the family indicated signs of depression, incoherent behaviour and intake of "amphetamine-like" drugs. Clinical examination revealed a Glasgow coma score of 9, symmetrical reactive pupils with mydriasis and no convulsions. The patient presented with rapid respirations and her blood pressure was 93/53 mmHg. The ionogram and the blood gas analyses were normal, while the blood alcohol level was 0.167 g/dL. Urinalysis revealed the presence of benzodiazepines and a high concentration of amphetamines (methcathinone: 17.24 mg/L, ephedrine: 11.60 mg/L and methylephedrine: 11.10 mg/L). In addition, serum analysis revealed bromazepam (8.89 mg/L), methcathinone (0.50 mg/L) and methylephedrine (0.19 mg/L). This case showed that the consumption of bromazepam and alcohol altered the typical clinical symptoms of cathinone derivative intoxication, namely hypertension and convulsions. Methylephedrine, an impurity resulting from the alkylation of a primary amine, can be considered a chemical tag indicating fraudulent synthetic origin of the drug. This case describes a documented example of new addictive behaviour of "well-educated" people involving the intake of methcathinone, a postindustrial psychostimulant intentionally combined with an anticonvulsant benzodiazepine. However, this specific case suggests that in spite of a very high bromazepam concentration in presence of the potentiator alcohol, the vital respiratory function would be probably maintained, thanks to the association with methcathinone.

Khat chewing is a risk factor for acute myocardial infarction: a case-control study

AIM

Khat chewing is a common habit in Yemen and east African countries. Millions of people chew khat leaves daily for its euphoric and energetic effects and to increase alertness. Cathinone, the main active substance in fresh khat leaves, has sympathomimetic effects which increase heart rate and blood pressure. The aim was to examine the hypothesis that khat chewing is a risk factor for acute myocardial infarction (AMI) using a hospital-based matched case-control study.

METHOD

Between 1997 and 1999, we selected 100 patients admitted to the Al-Thawra teaching hospital Sana'a ICU, Yemen with acute myocardial infarction. 100 control subjects, matched to cases for sex and age, were recruited from the outpatients clinics of the same hospital. A questionnaire was completed for case and control groups covering personal history of khat chewing, smoking, hypertension, diabetes and any family history of myocardial infarction. A blood sample was collected for performing lipid profiles. Cases and controls were compared by analysis conducted using conditional logistic regression which corrected for baseline imbalances leading to less biased estimations of odds ratio (OR). The risk associated with each classical factor and khat chewing habits was then investigated. OR values greater than 2.5 indicated a significant risk factor.

RESULTS

Khat chewing was significantly higher among the AMI case group than control group (OR = 5.0, 95% CI 1.9-13.1). A dose-response relationship was observed, the heavy khat chewers having a 39-fold increased risk of AMI.

CONCLUSION

This study indicates that khat chewing is associated with AMI and is an independent dose-related risk factor for the development of myocardial infarction.

Long-term feeding effects of Catha edulis leaves on blood constituents in animals

In this study, the long-term (6 months) biochemical effects of varying levels of Catha edulis leaves on the plasma concentration of glucose, triglycerides, cholesterol, HDL-cholesterol, total protein, albumin, uric acid, urea and creatinine were examined. Our results demonstrated a significant decrease in plasma cholesterol throughout the treatment period by all levels of C. edulis leaves tested. This significant decrease in plasma cholesterol was halved at the end of the treatment period and corresponded with a significant increase in plasma HDL-cholesterol and a significant decrease in plasma glucose and triglycerides concentrations. Moreover, C. edulis treatment increased plasma uric acid significantly, in a time-dependent manner with the higher concentrations (20% and 30%) of C. edulis leaves. Only plasma albumin was decreased significantly at the end of the treatment period, with no significant effect on plasma total protein. This also coincided with a significant, dose-dependent decrease in plasma urea at month 6, with no significant effect on plasma creatinine concentration.