Poor working memory and reduced blood pressure levels in concurrent users of khat and tobacco

Khat and neurobehavioral functions: A systematic review

Background

Khat is a plant that is used for its amphetamine-like stimulant properties. However, although khat is very popular in Eastern Africa, Arabian Peninsula, and the Middle East, there is still a lack of studies researching the possible neurobehavioral impairment derived from khat use.

Methods

A systematic review was conducted to identify studies that assessed the effects of khat use on neurobehavioral functions. MedLine, Scopus, Cochrane, Web of Science and Open Grey literature were searched for relevant publications from inception to December 2020. Search terms included (a) khat and (b) several cognitive domains. References from relevant publications and grey literature were also reviewed to identify additional citations for inclusion.

Results

A total of 142 articles were reviewed, 14 of which met the inclusion criteria (nine human and five rodent studies). Available human studies suggest that long term khat use is associated with significant deficits in several cognitive domains, including learning, motor speed/coordination, set-shifting/response inhibition functions, cognitive flexibility, short term/working memory, and conflict resolution. In addition, rodent studies indicated daily administration of khat extract resulted in dose-related impairments in behavior such as motor hyperactivity and decreased cognition, mainly learning and memory.

Conclusions

The findings presented in this review indicates that long-term khat use may be contributing to an impairment of neurobehavioral functions. However, gaps in literature were detected that future studies could potentially address to better understand the health consequences of khat use.

Prevalence and determinants of chewing khat among women in Ethiopia: data from Ethiopian demographic and health survey 2016

BACKGROUND

In Ethiopia and other countries in eastern Africa, khat abuse is an increasing public health problem. Levels of use appear to be increasing in women, who are more vulnerable to khat-related problems. However, population-based data are lacking as studies have been small and related to specific settings. This study aimed to contribute to current knowledge on the prevalence of chewing khat and associated factors among women in Ethiopia, using data from the 2016 Ethiopian national demographic and health survey.

METHODS

The 2016 EDHS used a two-stage stratified sampling design to select households. A total of 645 enumeration areas (202 urban and 443 rural) were selected, based on the 2007 Ethiopia Population and Housing Census. In these, 18,008 households were considered, from which 15,683 women were included from individual households. The women were interviewed by trained lay interviewers. Data were tabulated and logistic regression was used to examine mutually adjusted associations, expressed as adjusted odds ratios.

RESULTS

The lifetime prevalence of chewing khat among women was 9.9%. Current khat use was 8.4%, with a mean of 14.2 days of use in the last month. Khat use increased with increasing age, remaining constant after age 35 years, having one child, lower educational level, being Muslim by religion and not pertaining to the lowest wealth index category. Not being in a marital relationship with the most recent sex partner and Protestant religion were protective factors.

CONCLUSION

Lifetime prevalence of chewing khat among women in Ethiopia is substantial and associated with specific sociodemographic risks. These can be used in targeted public health efforts to control the use of khat and reduce the associated health and economic burden.

Influences of Fasting on Stress Response and Withdrawal Symptoms in Habitual Khat Users

BACKGROUND

Fasting changes mood and physiological states. Substance use, such as khat use, is prohibited during fasting during Ramadan, a traditional practice among Muslims. Habitual khat use is associated with increased negative affect and altered psychobiological stress responses. Effects of fasting on stress responses, mood, and withdrawal symptoms among khat users have not been examined.

METHODS

In this study, 80 individuals completed an ambulatory monitoring period and a laboratory assessment session. Participants who completed the study while fasting during Ramadan were matched by gender and khat use status with participants who completed the study while not fasting. This resulted in 40 participants (12 females and 28 males; 25 khat users and 15 nonusers) in each fasting group. Cardiovascular (blood pressure and heart rate) and subjective measures were collected throughout the laboratory stress session. A mental arithmetic challenge was used to induce stress. In addition, self-reported mood and withdrawal measures were collected multiple times during the ambulatory assessment.

RESULTS

Khat users reported greater negative affect than nonusers. Results from the ambulatory study indicated that withdrawal symptoms were lower during evening hours in the fasting group than in the no-fasting group. Stress-related changes in positive and negative affects were flattened in the fasting group relative to the no-fasting group. Khat users reported reduced blood pressure responses relative to nonusers.

CONCLUSION

These preliminary results demonstrate that fasting is associated with reduced negative affect and withdrawal symptoms in khat users. Khat use was related to blunted blood pressure stress responses, but this was independent of fasting. Due to the small sample size, these results should be replicated with a large sample and comprehensive stress tasks.

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.

Cognitive deficits and neurotoxicity induced by synthetic cathinones: is there a role for neuroinflammation?

RATIONALE

The number of synthetic derivatives of cathinone, the primary psychoactive alkaloid found in Catha edulis (khat), has risen exponentially in the past decade. Synthetic cathinones (frequently referred to as "bath salts") produce adverse cognitive and behavioral sequelae, share similar pharmacological mechanisms of action with traditional psychostimulants, and may therefore trigger similar cellular events that give rise to neuroinflammation and neurotoxicity.

OBJECTIVES

In this review, we provide a brief overview of synthetic cathinones, followed by a summary of cognitive deficits in animals and humans that have been documented following acute or repeated exposure. We also summarize growing evidence from in vitro and in vivo studies for synthetic cathinone-induced neurotoxicity, and provide a working hypothetic model of potential cellular mechanisms.

RESULTS

Synthetic cathinones produce varying effects on markers of monoaminergic terminal function and can increase the formation of reactive oxygen and nitrogen species, induce apoptotic signaling, and cause neurodegeneration and cytotoxicity. We hypothesize that these effects result from biochemical events similar to those induced by traditional psychostimulants. However, empirical evidence for the ability of synthetic cathinones to induce neuroinflammatory processes is currently lacking.

CONCLUSIONS

Like their traditional psychostimulant counterparts, synthetic cathinones appear to induce neurocognitive dysfunction and cytotoxicity, which are dependent on drug type, dose, frequency, and time following exposure. However, additional studies on synthetic cathinone-induced neuroinflammation are clearly needed, as are investigations into the neurochemical and neuroimmune mechanisms underlying their neurotoxic effects. Such endeavors may lead to novel therapeutic avenues to promote recovery in habitual synthetic cathinone users.

Anger, anxiety, and depressive affect as predictors of stress-induced cortisol production in khat and tobacco users

INTRODUCTION

Glucocorticoid activity is disrupted in substance users including khat chewers who also use tobacco. Anger, dysphoria, and anxiety can mediate this relationship. The aim of this study was to contrast emotion dysregulation and substance use variables as predictors of post-stress cortisol output.

MATERIALS AND METHODS

Comparable numbers of males (n = 90) and females (n = 85) including controls, khat only, and concurrent khat and tobacco users participated in a stress study. Depressive affect, anxiety, anger, substance use patterns, and saliva samples were collected following a standardized laboratory stress manipulation.

RESULTS

Regression analysis showed that high depression and low anxiety was associated with high post-stress cortisol, but only in co-users of tobacco and khat. Males, but not females, showed a significant association between co-use of khat and tobacco and cortisol, which appears to be mediated by frequency of use. The link between anxiety and post-stress cortisol in the co-users remained significant after controlling for nicotine dependence and substance use frequency.

CONCLUSION

Anxiety predicted the neuroendocrine consequences of concurrent use of tobacco and khat above and beyond sex, nicotine dependence, anger, and substance use frequency. Sex differences, however, are related to differences in nicotine dependence.

Stress and Addiction: When a Robust Stress Response Indicates Resiliency

OBJECTIVE

Stress reactivity research has traditionally focused on the idea that exaggerated responses to stress may have adverse effects on health. Accumulating evidence suggests that attenuated responses to stress and delayed recovery may also be problematic.

METHODS

This review focuses on the role of the stress response of the hypothalamic-pituitary-adrenocortical axis, the endogenous opioid system, and the cardiovascular system in hypertension, pain perception, and addictive behaviors. Results from multiple methods of assessment and stress paradigms conducted in our laboratory over the past two decades are integrated with research from other investigators and with existing theories.

RESULTS

Research indicates that exaggerated biological and physiological responses to stress and attenuated pain perception are associated with hypertension and risk for cardiovascular diseases. This research complements work linking reduced stress responses with enhanced pain sensitivity and discomfort. Multiple studies have also demonstrated that an attenuated stress response is linked to exacerbation of withdrawal symptoms and relapse in nicotine addiction. Evidence indicates important moderators (i.e., sex, personality traits, and early life adversity) and hypothalamic-pituitary-adrenocortical- and endogenous opioid system-related mechanisms in the altered response to stress. I integrate these findings in a conceptual model emphasizing that robust stress responses in the context of addiction and relapse should be considered as a marker of resiliency.

CONCLUSIONS

A blunted stress response may indicate long-term physiological dysregulation that could usher harmful consequences for cardiovascular disease, pain perception, and addictive disorders. The impact of dysregulation is influenced by multiple individual and situational factors that should be considered in evaluating the clinical significance of stress response dysregulation.

Khat (Catha Edulis) as a Risk Factor for Cardiovascular Disorders: Systematic Review and Meta-Analysis

Background

About 20 million people worldwide are believed to be using khat. Although some studies reported that khat chewing might result in cardiovascular disorders, conclusive evidence is limited.

Method

The objective of this review was to synthesize the best available evidence for the effect of khat on the cardiovascular system. Databases searched were PubMed, Cochrane database of systematic reviews, CINAHL, poplin, LILACS, MedNar and Scopus. All papers included in the review were subjected to rigorous appraisal using the Joanna Briggs Institute (JBI) standardized critical appraisal tool. Review Manager Software (Revman 5.3) was used for meta-analysis and effect size and the 95% confidence interval (CI) was calculated.

Result

Data was extracted from 10 articles. Our meta-analysis included 9,207 subjects, (2123 chewers and 7084 non-chewers, respectively) to elucidate the effect of khat on heart rate, diastolic and systolic blood pressure. The mean diastolic and systolic blood pressure of khat chewers was higher than the non-chewers with a mean difference of 5.1 mmHg, 95%CI [2.7,7.5] and 7.9 mmHg, 95%CI [2.65, 13.18], respectively. Similarly, the heart rate of the chewers remained consistently higher, making the mean difference of 6.9 beats/min, 95%CI [0.5, 13.3]. In addition, khat was found to have either a causative or worsening effect on stroke, myocardial infarction and heart failure.

Conclusion

We showed that khat chewing could significantly affect the cardiovascular system through its effect on heart rate and blood pressure. Therefore, health promotion should be aimed to encourage quitting khat chewing.

Khat Use is Associated with Tobacco, Alcohol, and Illicit Drug Use: A Cross-Sectional Examination in the United States

No study has systematically examined khat (Catha edulis) use and its linkages with other substance use in the United States. This study provides novel findings related to the associations of khat with other substance use among immigrants in metropolitan areas of Minnesota where large East African communities reside. Using a convenience sampling, a total of 261 individuals completed a brief face-to-face interview during which demographic information and substance use were assessed. The proportion of lifetime and current use were 30% and 6.6% for khat, 35% and 18% for tobacco, 35% and 21% for alcohol, and 13% and 10% for other illicit drugs. Self-report history of khat use was associated with tobacco, alcohol, and other drug use. Tobacco use was related to alcohol and use of other drugs. The results suggest that a history of khat use is useful in identifying individuals who are vulnerable to substance-use-related problems. The findings indicate the need for more research on khat in the U.S.

Prevalence of khat chewing and its effect on academic performance in Sidama zone, Southern Ethiopia

BACKGROUND

Khat use is a well-established public health problem in Yemen, Arabian Peninsula, and Ethiopia. Along with its large scale production, the magnitude of khat use is increasing among students.

OBJECTIVE

This study was intended to assess the prevalence, determinants, and effect of khat use on academic performance of high school students in Sidama Ethiopia.

METHODOLOGY

A cross-sectional study was conducted from April to June 2015. We used a stratified sampling technique to draw a total of 1,577 students. The data was collected using self-administered questionnaires and analyzed using SPSS version 20. Descriptive statistics and logistic regression models were used to determine the prevalence, effects, and predictors of khat use.

RESULT

The life time and current prevalence of khat use were 14.6% and 13%, respectively. Smoking cigarette (AOR=5.1, 95% C.I: 2.3-14.3), drinking alcohol (AOR=3.0, 95% C.I: 1.4-6.3), having a family growing khat (AOR=2.0, 95% C.I: 1.1-2.5), having friend chewing khat (AOR=3. 95% C.I: 2.0-4.6), were some of factors that increased the odds of students' khat use. Student's khat use increased the odds of student's poor academic performance (AOR=2.1, 95% C.I: 1.1-3.9).

CONCLUSION

The prevalence of khat use in high khat producing districts of Sidama and its contribution to poor academic performance demand prompt intervention.

Sleep disturbances and memory impairment among pregnant women consuming khat: An under-recognized problem

Khat (Catha edulis) is a evergreen flowering shrub that is cultivated at high altitudes, especially in East Africa and the southwest of the Arabian Peninsula. The plant contains alkaloids, of which cathinone and cathine have structural similarity and pharmacological action similar to amphetamines. The leaves are, therefore, consumed in some regions as a psychoactive stimulant due to cultural beliefs and misperceptions on the health benefits of khat consumption. This resulted in a growing prevalence of khat consumption among pregnant women. The myriad of physiological changes associated with pregnancy impairs sleep and memory. Moreover, khat has also been shown to have adverse effects on memory and sleep. Therefore, its use during pregnancy may further aggravate those impairments. The purpose of this mini-review is to summarize the changes in sleep and memory during pregnancy and the evidence supporting a relationship between khat consumption and neurocognitive deficits and sleep dysfunctions. The misperceptions of beneficial effects of khat, the high prevalence of consumption among pregnant women, and the possibility of under-reporting of khat abuse do necessitate the development of alternative methodologies to identify cases of unreported khat abuse in pregnant women. It is proposed that screening for sleep problems and memory deficits may help identify under-reported cases of khat abuse in pregnant women.

Correlates of Concurrent Khat and Tobacco Use in Yemen

BACKGROUND

Habitual substance use poses public health threat. This is a growing concern in countries where one or more substances are commonly used. Many individuals in Middle Eastern and East African countries use khat (Catha edulis), a stimulant often accompanied by smoking. However, few systematic attempts have been made to characterize patterns of concurrent khat and tobacco use.

OBJECTIVES

To examine correlates such as gender and patterns of khat and tobacco use in concurrent users and khat-only users.

METHODS

This study used a cross-sectional design with a face-to-face interview method including 151 (74 women) concurrent users of khat and tobacco and 141 (76 women) khat-only users in Yemen. Data collection was completed in 2012. Analysis of variance (ANOVA) and logistic regressions were conducted to examine gender and khat use group differences in use patterns.

RESULTS

Reported frequency and intensity of khat use were greater in men than in women. Men and women khat users used different tobacco products and beverages while using khat. Khat use was more frequent in concurrent users relative to khat-only users. Earlier age of onset of khat use was associated with greater number of cigarettes smoked during a typical khat session. Approximately 70% of concurrent users reported initiating khat use prior to tobacco use. Conclusions/Importance: The results provide support for gender differences in khat and tobacco use, differences in khat use pattern between concurrent users of khat and tobacco and khat-only users, and positive associations between khat and tobacco use.