Qat Chewing and Risk of Potentially Malignant and Malignant Oral Disorders: A Systematic Review

The effects of khat (Catha edulis) use on the genitourinary system: A systematic review and meta-analysis

The objective of the current study is to conduct a meta-analysis of the existing literature concerning the potential impact of khat on the reproductive systems. Five international databases, Embase, Medline/PubMed, Scopus, Web of Knowledge (ISI), and ProQuest, were searched from inception up to the end of January 2024. The Joanna Briggs Institute (JBI) Critical Appraisal Checklist was used for quality assessment of included studies. After several screening phases,10 articles were included in the final analysis. The pooled meta-analysis showed that women who use khat during pregnancy had a significantly higher chance of having low birth weight (LBW) (OR= 2.51, 95% CI: 1.61-3.95, p-value < 0.001) and congenital anomalies (OR= 3.17, 95% CI: 1.31-7.73, p-value = 0.011) compared to nonusers. The obtained results of the meta-analysis showed that the consumption of khat significantly reduces semen volume (standardized mean difference = -0.903, 95% CI: -1.801 to -0.007, p = 0.048). In conclusion, our study show that significant associations with LBW, congenital anomalies, and reduced semen volume underscores the necessity for additional research to delve deeper into the intricate complexities of how khat affects reproductive health in both women and men.

Oral health-care needs among clients receiving alcohol and other drugs treatment-A scoping review

ISSUES

Poor oral health is a significant problem among people who access alcohol and other drugs (AOD) health services, yet little is known about their oral health-care needs and whether any interventions and guidelines are implemented within AOD treatment services.

APPROACH

A scoping review was conducted to identify scientific literature in three focus areas: oral health knowledge, attitudes and practices of clients and clinicians at AOD-related services; oral health guidelines for AOD clinicians; and interventions that describe clinicians promoting oral health among clients.

KEY FINDINGS

Thirty-two reports were identified. Twenty-three studies focused on the oral health knowledge, attitudes and practices of AOD clients, but none of the studies explored perspectives of clinicians. Seven clinical practice guidelines were identified but recommendations varied. Only two interventions in which an AOD clinician promoted oral health were identified.

IMPLICATIONS

Most reports provided insight into the perspectives of clients accessing AOD treatment services. Little evidence demonstrated that clinical practice guidelines were being implemented into practice, or that oral health promotion was part of the tasks of AOD clinicians.

CONCLUSION

This review identified oral health knowledge gaps and perceived poor attitudes that appeared to be reflected in certain oral health practices among clients. This finding indicates a need to educate clients about oral health while receiving AOD treatment. There was an absence of research about the needs for AOD clinicians to advocate for good oral health, and little evidence exists about effective interventions that could enhance integrating oral health care into AOD treatment services.

Risks of khat chewing on the cardiovascular, nervous, gastrointestinal, and genitourinary systems: A narrative review

Khat is an evergreen plant and its fresh green leaves and buds are chewed for several hours a day for its psychostimulant response. This study aimed to review the effects of khat chewing on the body. PubMed was searched for literature on the different aspects of khat chewing to summarize its effects on different body systems. The major effects of khat chewing are those on the cardiovascular system including increased blood pressure, increased heart rate, and increased risk of myocardial infarction. It causes insomnia, stress, depression, hallucination, and increased risk of brain stroke. It causes dental caries, bad oral hygiene, periodontitis, increased oral mucosal ulcers, and increased gingival bleeding and recession. Khat chewing causes loss of appetite, gastritis, constipation, and hemorrhoids, and increased risk of hepatotoxicity and liver cirrhosis. Ultimately, it causes weak micturition, decreased sperm motility and count, and low birth-weight offspring in khat chewing mothers. The published articles about khat chewing in journals indexed in the PubMed was reviewed. Inclusion criteria involved each article available with English language and have a reported new effect of khat chewing.

Heterogeneity in head and neck cancer incidence among black populations from Africa, the Caribbean and the USA: Analysis of cancer registry data by the AC3

BACKGROUND

Africa and the Caribbean are projected to have greater increases in Head and neck cancer (HNC) burden in comparison to North America and Europe. The knowledge needed to reinforce prevention in these populations is limited. We compared for the first time, incidence rates of HNC in black populations from African, the Caribbean and USA.

METHODS

Annual age-standardized incidence rates (IR) and 95% confidence intervals (95%CI) per 100,000 were calculated for 2013-2015 using population-based cancer registry data for 14,911 HNC cases from the Caribbean (Barbados, Guadeloupe, Trinidad & Tobago, N = 443), Africa (Kenya, Nigeria, N = 772) and the United States (SEER, Florida, N = 13,696). We compared rates by sub-sites and sex among countries using data from registries with high quality and completeness.

RESULTS

In 2013-2015, compared to other countries, HNC incidence was highest among SEER states (IR: 18.2, 95%CI = 17.6-18.8) among men, and highest in Kenya (IR: 7.5, 95%CI = 6.3-8.7) among women. Nasopharyngeal cancer IR was higher in Kenya for men (IR: 3.1, 95%CI = 2.5-3.7) and women (IR: 1.5, 95%CI = 1.0-1.9). Female oral cavity cancer was also notably higher in Kenya (IR = 3.9, 95%CI = 3.0-4.9). Blacks from SEER states had higher incidence of laryngeal cancer (IR: 5.5, 95%CI = 5.2-5.8) compared to other countries and even Florida blacks (IR: 4.4, 95%CI = 3.9-5.0).

CONCLUSION

We found heterogeneity in IRs for HNC among these diverse black populations; notably, Kenya which had distinctively higher incidence of nasopharyngeal and female oral cavity cancer. Targeted etiological investigations are warranted considering the low consumption of tobacco and alcohol among Kenyan women. Overall, our findings suggest that behavioral and environmental factors are more important determinants of HNC than race.

Exposure to DDT and HCH congeners and associated potential health risks through khat (Catha edulis) consumption among adults in South Wollo, Ethiopia

Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public health concern. In a market-based study, from five popular khat varieties, a total of 35 composite khat samples were analyzed for dichlorodiphenyltrichloroethane (DDT) and its main transformation products, and four hexachlorocyclohexane (HCH) isomers. Extraction was carried out by quick, easy, cheap, effective, rugged and safe method (QuEChERS). OCP concentrations were determined by head space solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS). Every sample contained β-HCH above the maximum residue limit set by the European Commission. For total DDT, this was the case for 25.7% of the samples. The ratios of (p,p'-DDD + p,p'-DDE) to p,p'-DDT were less than one for 85% of khat samples, demonstrating recent use of DDT in khat farmlands. Conversely, the ratio of β-HCH to total HCH varied from 0.56 to 0.96, implying historical input of technical HCH. Assuming a daily chewable portion of 100 g, dietary intakes of p,p'-DDT, total DDT and total HCH by adults ranged from 3.12 to 57.9, 6.49 to 80.2 and 39.2 to 51.9 ng (kg body weight)^-1 day^-1, respectively. These levels are below acceptable levels suggested by international organizations. Chewing khat showed lower non-cancer health risk, but showed relatively higher cancer risk in terms of OCPs. Because khat is chewed without being subjected to any treatment, uncertainties associated with estimated intakes and health risks should be low. Therefore, this practice is of great concern.

The Impact of Khat (Catha edulis) on Hemodynamics of the Common Carotid Arteries in Regular Khat Chewers: A Case-control Study Using Doppler Ultrasound

Background:

To evaluate the effect of chewing khat on the hemodynamics of the common carotid arteries (CCAs) using Doppler ultrasound imaging.

Methods:

This is a cross-sectional case–control study. Fifty volunteers who were chronic regular khat chewers were selected and compared with healthy nonkhat chewers. They were examined using Doppler imaging with a 7–10 MHz linear transducer. The resistivity index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity of the CCAs were determined according to the standard protocol of carotid Doppler ultrasound.

Results:

The RI and PI of the right and left CCAs were significantly higher in khat chewers compared to controls (P < 0.001). The PSV of the right and left CCAs was considerably higher in khat chewers compared to controls (P < 0.001 and 0.04, respectively).

Conclusion:

The Doppler values of blood flow velocity, resistivity, and pulsatility were significantly higher in chronic regular khat chewers compared to nonkhat chewers. Khat is a significant contributory factor for increasing the hemodynamics of the CCAs.

Tea in the Morning and Khat Afternoon: Health Threats Due to Khat Chewing

Khat or qat (Catha edulis) is a flowering plant with an Arabic name قات, regularly named as qāt, also is known by various descriptive names, such as Abyssinian tea, Somali tea, Arabian tea, Miraa, Jima, and Kafta in its endemic regions of the Horn of Africa and the Arabian Peninsula. Fresh leaves and tops of khat are chewed or dried and consumed as a tea to attain a state of euphoria and excitement; it also has appetite-reducing effects. Traditionally, khat is used as a socializing habit in Yemen and is also widely cultivated because of its high income. However, in recent years the plant has been reported in England, Wales, Rome, Amsterdam, Canada, Israel, Australia, New Zealand, and the United States. Although it is believed that khat is a relatively low-risk drug, it's associated with an increased risk for various medical complications, including dental and oropharyngeal disease, gastrointestinal, cardiovascular, neuropsychiatric, obstetric, and even can be the cause of cancer. Our goal in this review article is to revise and determine the relationship between chewing khat and its health issues. Additionally, we tried to determine the mechanism involved in health hazards due to consuming the khat.

Evaluation of Khat (Catha edulis) Use as a Risk Factor of Cancer: A Systematic Review

Background:

Conducting systematic review to evaluate plant use as a risk factor to cancer could be challenging. A systematic and well-balanced method should be applied to accommodate in vivo and in vitro studies to make a final decision. In this article, khat, a recreational plant used in some Arabic and African regions, was employed as an example to systematically determine its relationships to the premalignant and cancerous conditions.

Methods:

Systematic database search was performed to recruit original human, animal or in vitro studies on khat and cancer. Sixteen studies fulfilled the inclusion criteria and subjected to assessment using Risk of Bias (RoB). Office of Health and Translation (OHAT) approach was used to rate the confidence level in the body of evidence. The evidence was integrated to establish the relationships between khat, premalignant conditions and cancer.

Results:

Seven out of eight studies showed that khat causes premalignant oral lesions with moderate evidence level. Four studies showed that khat causes cancer with low evidence level and another three studies showed that khat has anti-cancer effect with moderate to high evidence level. Only one study suggested that khat is unrelated to cancer.

Conclusion:

RoB and OHAT approach are reliable systematic tools to evaluate plant risk to cancer and provide objective and uniform summary regardless of the study type. In conclusion, our pooled analysis did not find a direct relationship between khat and cancer but anti-cancer effect would require to be proofed on human studies.

Phytochemical Screening and Cytotoxic Properties of Ethanolic Extract of Young and Mature Khat Leaves

The khat plant has been culturally used in many parts of Africa and the Arabian Peninsula for many years to induce psycho-stimulating effect. Because of the global wide-spreading nature, khat chewing is being considered as a universally growing problem. Catha abbottii, Catha edulis, and Catha transvaalensis are the three species of khat commonly chewed in Saudi Arabia and nearby regions. Khat users usually prefer to chew young leaves over mature ones due to the diverse effects produced by both. Though many of the constituents of khat leaves have been identified, the complete phytochemical profile of young and mature leaves was not performed or compared; also, no evidence is available to affirm the cytotoxicity of young or mature leaves. Therefore, this study aimed to investigate the phytochemical basis of the differential response of the young and mature leaves and to assess the cytotoxicity of young and mature khat leaves. Ethanolic extracts of young and mature leaves of three khat cultivars were subjected to GC-MS. Hierarchical cluster analysis revealed the existence of two major clusters. The extracts of young leaves were found to contain the maximum content of cathinone; however, methoxyamphetamine was found in only one extract of young leaves. Cytotoxicity investigations were also conducted on both types of leaves using three cancer cell lines, human breast adenocarcinoma, human ovary adenocarcinoma, and human colon adenocarcinoma and also normal human fetal lung fibroblast cell line was used. All extracts showed comparable cytotoxicity, IC50 ranging from 22–59 μg/mL on the cancer cells; however, we observed more cytotoxicity against normal cells (IC50: 6–41 μg/mL). The predominant cytotoxicity on normal cells may pose many health hazards to khat consumers.

Link between perceived oral and general health status among Yemeni adult dental patients

BACKGROUND

Self-perceived health is an essential measure of health status and even a paramount predictor of mortality. So long as it is said that oral health (OH) and general health (GH) are mirrors to each other. This study sought to determine how Yemeni adults rate their OH and GH, whether such a self-rating influenced by some potential risk factors, and whether both ratings (OH and GH) are correlated.

METHODS

A sample of 587 Yemeni dental patients aged 20 years and over were consecutively recruited. A structured interview form was used covering the following variables: age, gender, marital status, educational level, presence of dental prosthesis (DP), smoking and Qat chewing habits as independent variables, along with questions on "perceived oral health (POH)" and "perceived general health (PGH)" as dependent variables. The bivariate and multiple ordinal regression analyses were applied at P-value < 0.05.

RESULTS

Most of participants were women (73.6%), and married (71.4%), and more than half of them were young adults (58.2%), with high educational levels (53.3%), and not having DP. Only 310 participants responded to the questions on smoking and Qat chewing habits. Of these, 88.5% were non-smokers and 62.1% were Qat non-chewers. Up to 50% of the participants reported their POH as poor or fair, while lower proportions of participants (17%) reported their PGH as such. Younger age (compared to elders), high education levels (compared to primary education) and being single (compared to married) significantly revealed better levels of POH, while high education levels and being females significantly revealed better levels of PGH. Smoking and Qat chewing habits were found to have no effect on the perception of POH or PGH. POH and PGH were found to be significantly correlated (r = 0.486; P < 0.001).

CONCLUSION

Higher levels of oral health problems can be anticipated among patients who perceive poor general health, and vice versa. The age, marital status and education were independent determinants of POH, while the gender and education were independent determinants of PGH.

User Experiences of Prescription and Over-The-Counter Drug Abuse in Aden City, Yemen

Khat chewing is commonplace in Yemen, but little else is known about the misuse of other drugs, especially how such misuse may intersect with Khat use. The aim of this study was to investigate misuse of prescription and over-the-counter (OTC) drugs in community pharmacies in Aden city, from the users’ perspective. A qualitative in-depth-interview study was undertaken with fifteen known or suspected drug misusers, recruited through community pharmacies. Thematic analysis was used to identify the main emergent themes around experience of prescription and OTC drug misuse. The majority of interviewees were male (n = 11/15) with an age range of 21–40 years. Benzodiazepines, Tramadol, and Ketoprofen were the most commonly misused drugs. Four main themes were identified: Experience sought with drugs; awareness of problematic drug use; pattern and methods of misuse; and the role of healthcare professionals in responding to misuse. The study highlighted different issues, such as the practice of mixing different OTC and prescription drugs with Khat to heighten the effects or manage associated pain, and drug misuse by females and by health care professionals. The study also suggested that physicians and pharmacists fear counselling such people, probably with the risk of violence as a contributory factor.

Individual and Integrated Effects of Potential Risk Factors for Oral Squamous Cell Carcinoma: A Hospital-Based Case-Control Study in Jazan, Saudi Arabia

Background: Oral cancer is the sixth most common cancer in the world, with a high prevalence reported in Jazan province of Saudi Arabia. The objectives of this study were to check individual and integrated effects of potential risk factors for oral squamous cell carcinoma. Materials and methods: A case control study was designed with a sample of 210 subjects, in which histopathologically confirmed incident cases (n=70) and controls (n=140) matched for age, gender and referral route, were recruited. Differences in exposure to potential risk factors between cases and controls were assessed using chi-square and McNemar analyses. A logistic regression model with interactions was applied to check individual and integrated effects. Results: Mean age of the sample was 55 years (+ 20 years). Shammah (O.R = 33.01; C.I = 3.22 – 39.88), shisha (O.R = 3.96; C.I = 0.24 – 63.38), and cigarette (O.R = 1.58; C.I = 0.13, 2.50) consumption was significantly associated (P<0.05) with oral squamous cell carcinoma development. In contrast, Khat chewing (O.R = 0.67; C.I = 0.19-2.36) was without significant effect. An increase in odds ratios was observed when combinations of shammah and shisha (O.R = 35.03; C.I = 11.50-65.66), shisha and cigarettes (O.R = 10.52; C.I = 1.03 – 33.90) or shamma and cigarettes (O.R = 10.10; C.I = 0.50 - 20.40) were used. Conclusion: Combined exposure to risk-factors has serious implications and policies on oral cancer prevention should be designed with attention to this aspect.

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 (Catha edulis) and its oral health effects: An updated review

Khat or qat (Catha edulis) is a plant that grows in East Africa and southern Arabia. The leaves and twigs of this small tree are chewed by several millions of people worldwide for their stimulating amphetamine-like effects. The reported prevalence of khat chewing in Europe and the USA is on the rise, especially with global migration. Long-term khat chewing has several detrimental general and oral health effects. The aim of the present study was to review the current literature regarding khat use and its association with oral and dental diseases, with particular emphasis on its link with oral keratotic white lesions and oral cancer. We searched the literature to identify all relevant articles. Studies showed that khat is associated with several oral and dental conditions, including keratotic white lesions, mucosal pigmentation, periodontal disease, tooth loss, plasma cell stomatitis, and xerostomia. There are limited data on the incidence of dental caries among khat chewers. The evidence that khat chewing is a risk factor for oral cancer is still weak, and is mainly based on anecdotal case reports and uncontrolled studies.

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.

Exposure to DDT and its metabolites from khat (Catha edulis) chewing: Consumers risk assessment from southwestern Ethiopia

Khat (Catha edulis) is one of the most consumed plant in the horn of African countries. However, it is a stimulant plant that has several side effects on the health of consumers. On top of that, the khat leaves used for human consumption are often contain contaminants such as pesticide residues. The present study aims to investigate the level of DDT residue and its metabolites (p'p-DDE, p'p-DDD, o'p-DDT and p'p-DDT) in khat samples and to undertake exposure assessment to consumers. The khat samples were collected from local markets in southwestern Ethiopia. Consumption survey was undertaken using 24 h recall method for both male and female khat consumers. The finding showed that 80% of the khat samples contained DDT and its metabolites. Some of the residues were above the maximum residue limit (MRL) set by Food and Agricultural Organization (FAO). The concentration of p'p-DDE and p'p-DDT in khat were in the range of 0.033-0.113 and 0.010-0.026 mg/kg, respectively. High concentration of the metabolite (p'p-DDE) compared to the parent compound (p'p-DDT) revealed the historical use of DDT in the study area. Probabilistic exposure analysis indicated that the mean and 97.5 percentile (P97.5), of the estimated daily intake of total DDT were 0.002 and 0.006 mg/kg bw/day, respectively. The study concluded that khat consumers are exposed to the stimulant effect of the plant as well as DDT and its metabolites in Jimma zone.