Abstract
Background: Khat chewing has a negative impact on an individual’s life. Objectives: The study was execute to assess health sciences students’ knowledge and attitudes regarding khat use in Yemen. Methods: This survey involved health sciences students from Aden University. Approximately 500 participants were selected through convenience sampling. The data were collected using a structured and validated self-administered questionnaire. The data were tabulated and descriptively analyzed. Results: The total number of respondents was 500. Almost half of the students reported that they chewed khat (n = 239, 48%). Approximately 66% (n = 330) of the students spent 2000 Yemeni riyals or less (USD1 = YER249.9) per day on khat. The main reasons for chewing khat were ‘it is a social habit’ (n = 155, 31%), followed by ‘it improves my concentration when studying or working’ (n = 140, 28%). Students knew that the effects of khat are similar to those of amphetamines (n = 210, 42.0%) and that khat is addictive (n = 254, 50.8%). Additionally, they knew that cathinone is the dependence-producing constituent of khat leaves (n = 269, 53.8%). The students agreed with the following statements: ‘I will advise people to cease khat use’; ‘Khat chewing is harmful to health’; ‘Children and adolescents should not chew khat’; ‘Khat chewing helps people stay awake’; and ‘Health professionals serve as role models for patients and the public’. Conclusions: Khat chewing is prevalent among Yemeni university health sciences students. Only about half of the students recognized health risks associated with khat use. Also, among those who used khat, students endorsed positive benefits such as improved concentration.
Introduction
Khat (Catha edulis) is an evergreen plant in the Celastraceae family (Kennedy, Citation1987). It is largely cultivated in Yemen and African countries, and its fresh leaves and twigs are chewed by many people in these countries for 4–6 hr per day (Manghi et al., Citation2009). The practice involves placing fresh khat leaves on one side of the mouth and slowly chewing them to extract the juice, which is swallowed; the leaves remain in the buccal cavity (Schmidt-Westhausen, Al Sanabani, & Al-Sharabi, Citation2014).
Khat chewing is prevalent among Yemeni people, with a higher prevalence in males than in females (Wedegaertner et al., Citation2010). Khat contains several chemical compounds; however, the cathinone derivative is the main psychoactive compound that is responsible for the perceived increases in energy, alertness, ability to focus, self-esteem and libido that the plant induces (Numan, Citation2004). Some users experience nervousness, tension, restlessness, hypnagogic hallucinations, hypomania, depression, and violent behavior or psychosis (Hassan et al., Citation2000).
Long-term khat chewing has a negative impact on health and can cause many diseases, such as gastrointestinal disorders, cytotoxic effects in the liver and kidneys, respiratory problems, mental illnesses, cardiovascular disorders, sexual impotence and reproductive problems (Al-Motarreb, Al-Habori, & Broadley, Citation2010). Moreover, chronic khat use reportedly contributes to many dental and oral cavity diseases, such as periodontal diseases, dental discoloration and attrition, temporomandibular joint disorders, plasma cell stomatitis, mucosal pigmentation, keratotic lesions, and xerostomia (Hijazi, Jentsch, Al-Sanabani, Tawfik, & Remmerbach, Citation2016). In one study, the genotoxicity and teratogenicity of khat, particularly when used during pregnancy, were analyzed; however, the consequences were not well defined (Mwenda, Arimi, Kyama, & Langat, Citation2003). Another study reported the association between the development of oral cancer and chronic khat use (Soufi, Kameswaran, & Malatani, Citation1991). Previous studies described the addictive properties of khat and the presence of a range of dependence‐related symptoms among Yemenis and UK and Australian populations of African provenance (Kassim, Croucher, & Al'Absi, Citation2013; Nakajima, Hoffman, & Al'Absi, Citation2017; Young, Butt, Hersi, Tohow, & Mohamed, Citation2016). In addition, a 2017 study carried out in Ethiopia indicated the psychological severity of khat addiction in polysubstance users (Manzar et al., Citation2018). Khat chewing has a negative impact on not only health but also economic and social factors.
Due to its amphetamine-like effect, khat is often chewed by students during study periods and particularly during examination intervals to keep them alert and increase their ability to memorize information (Reda, Moges, Biadgilign, & Wondmagegn, Citation2012). Additionally, students gather and chew khat while studying together.
The sample of students in the current study on khat chewing covered a variety of socioeconomic backgrounds and cultural and cognitive levels and was representative of Yemeni society as a whole. Studying the demographic characteristics of students, their khat-chewing habits, and their knowledge of khat and its health effects is very important for understanding the dimensions of the problem and its prevalence and for developing appropriate solutions to reduce this unhealthy habit.
A previous study conducted among medical students in Taiz, Yemen, in 2010 evaluated khat-chewing behavior and knowledge and attitudes regarding khat among Yemeni medical students (MSs) and the effects of a seminar. The results of this study indicated a modest effect of the seminar on knowledge of and attitudes towards khat, because the students believed that chewing khat was a tradition in Yemeni culture (Yi, Kim, Hussein, & Saitz, Citation2012). In addition, another study was carried out in Taiz and Sana’a at local markets and shopping centers to develop a short-term method to evaluate attitudes and perceptions associated with khat. The results showed that knowledge, attitudes, and perceptions among khat users might act as risk or protective factors of khat use, while nonusers recognized the possible harm of khat (Nakajima, Hoffman, Alsameai, Khalil, & al'Absi, Citation2018). Khat chewing is common in Ethiopia, and a recent meta-analysis revealed that the prevalence of khat chewing among students is also high (Aklilu, Anteneh, & Hiwot, Citation2014; Gebrie, Alebel, Zegeye, & Tesfaye, Citation2018).
The present study aimed to assess health sciences students’ knowledge and attitudes regarding khat use in Aden, Yemen.
Methods
Study design
A cross-sectional descriptive study was conducted from July to November 2018 among health sciences students at Aden University in Aden, the port city of Yemen (population: approximately 800,000).
Ethical considerations
The study protocol was endorsed by the Ethics Research Committee of the Faculty of Medicine and Health Sciences, University of Aden. Written informed consent was obtained from all the participants after the objectives, importance and benefits of the research and the voluntary nature of participation were discussed. Participants were assured that all the data gathered would be handled with full confidentiality and would be used solely for research purposes.
Study population and sampling
The included students were from the departments of medicine, dentistry, pharmacy, nursing and laboratory sciences. A sample size of 500 participants was estimated. The students were selected through convenience sampling.
A simple formula was used to calculate the sample size, where n=sample size, Z = Z statistic for a given level of confidence, P=expected prevalence or proportion (in a proportion of one; if 50%, p = .5), and d=precision (in a proportion of one; 5%, d = 0.05). The Z statistic (Z) for the 95% confidence level was 1.96. By calculating a dropout rate of 30%, the total targeted sample size was n = 500.
Study tool development
The questionnaire was developed following a thorough review of the relevant literature. The face and content validity of the questionnaire were examined by asking three experts their opinions regarding whether the items covered important aspects of the domains measured. The questionnaire had 5 sections: (1) the demographic profile of the participant; (2) general matters related to khat use; (3) reasons for chewing khat; (4) knowledge of khat use; and (5) attitudes toward khat use. A pilot study was performed among 40 students who were not included in the final study. The internal consistency, i.e. the Cronbach's alpha, of the knowledge-attitude scale was 0.749. The Cronbach's alpha of the 21 knowledge items was 0.741, and the Cronbach's alpha of the 20 attitude items was 0.506. For the attitude scale, there were 8 items (1, 5, 8, 9, 11, 13, 16, and 19) that were negatively structured.
Data collection
The data were collected using a structured self-administered questionnaire. Students in different years were recruited in classrooms in the various departments. The questionnaire was distributed conveniently and was collected from the respondents on the same day.
Data analysis
The data collected from the questionnaires were analyzed using the Statistical Package for the Social Sciences (SPSS®) version 18.0 (SPSS Inc. Released 2009. PASW Statistics for Windows, Version 18.0. Chicago: SPSS Inc.). The frequency was measured for all the variables. The descriptive statistics, i.e. the frequencies (percentages), means (standard deviations, SDs) and medians (interquartile ranges, IQRs), were calculated.
Results
Sociodemographic profile of the students
A total of 500 students were included in the study. presents the sociodemographic characteristics of the students. The majority of the students who participated in the study were male (n = 319, 64%), had an average age of 24 years, were from the department of medicine (n = 196, 39%), were in year 3 of their academic program (n = 144, 29%), lived in an urban area (n = 331, 66%), had an average family size of 7 members and first used khat when they were 19 years old. The family sizes ranged from 2 to 16 members, with an average of 7 members (n = 114, 22.8%). Slightly more than half of the students had up to 7 family members (n = 286, 57%). The age of the students ranged from 18 to 32 years old, with an average age of 23 years (n = 97, 19.4%). Approximately 54% of the students (n = 268) were 18–23 years old. The age at which khat was first used ranged from 12 to 27 years. Approximately 56% (n = 134) of the students first used khat when they were between 12 and 19 years old, with a majority starting use at age 20 (23.0%). Approximately 62% (n = 148) first used khat when they were between 18 and 20 years old.
Table 1. Socio-demographic profile of the students (n = 500).
In terms of parental background, most of the fathers and mothers were educated at the elementary level (n = 141, 28%) and had basic reading and writing skills (n = 147, 29%). The majority of fathers were self-employed (n = 177, 35%).
General matters related to khat
Slightly more than half of the students claimed that they did not chew khat (n = 261, 52%) (). Slightly more than three-fourths of the students said they did not chew khat daily (n = 384, 76%). Approximately four-fifths (n = 413, 83%) did not smoke when they chewed khat. Approximately 20% (n = 98) chewed khat alone, approximately 44% (n = 218) chewed khat with friends and slightly less than one-third (n = 153, 31%) chewed khat with family members. When asked about the circumstances surrounding khat use, approximately two-fifths (n = 206, 41%) reported that they chew khat before exams, followed by ‘at parties’ (n = 118, 24%), ‘on the street’ (n = 107, 21%), ‘at home’ (n = 102, 20%) and before engaging in sports (n = 96, 19%). The amount of money spent on khat ranged from 500 to 6000 Yemeni riyals per day (exchange rate: USD1 = YER249.9); approximately one-tenth spent 2000 riyals (USD8) per day (n = 57, 11.4%), and approximately 66% (n = 330) spent 2000 riyals or less. Students reported chewing khat as little as once per week and as much as 7 times per week, with an average of 7 times (n = 114, 22.8%).
Table 2. General matters related to khat use.
Knowledge of khat among students
shows the reasons for chewing khat as reported by the students. Among those who indicated that they chewed khat, most students reported that ‘it is a social habit’ (n = 155, 31%), followed by ‘it improves my concentration when studying or working’ (n = 140, 28%); the least common reason was ‘it increases my confidence’ (n = 78, 16%).
Table 3. Reasons for chewing khat (n = 500).
The students’ khat knowledge results are presented in below. Approximately two-fifths (n = 210, 42.0%) of the students knew that the effects of khat are similar to those of amphetamines; that long-term khat use can cause hepatitis (n = 209, 41.8%); that long-term khat use can cause cancer (n = 216, 43.2%); and that slight trembling is a withdrawal symptom (n = 194, 38.8%).
Table 4. Knowledge on khat use among students (n = 500).
Approximately half of the students knew that khat can cause addiction (n = 254, 50.8%), while the rest did not know or were unsure. A similar proportion of the students knew that khat increases cognitive performance (n = 237, 47.4%); that long-term khat use can cause mental diseases (n = 240, 48.0%); that long-term khat use can cause cardiovascular diseases (n = 257, 51.4%); that aggression is a withdrawal symptom (n = 237, 47.4%); that hallucination is a withdrawal symptom (n = 247, 49.4%); that nightmares are a withdrawal symptom (n = 233, 46.6%); that decreased alertness is a withdrawal symptom (n = 239, 47.8%); and that depressive disorder is a withdrawal symptom (n = 251, 50.2%).
Slightly more than half (n = 272, 54.4%) of the students knew that the World Health Organization (WHO) considers khat a type of narcotic. When asked if they knew that cathinone was the dependence-producing constituent of khat leaves, slightly more than half (n = 269, 53.8%) said ‘Yes’, and approximately the same proportion knew that insomnia is a withdrawal symptom (n = 281, 56.2%). Approximately three-fifths of the students knew that khat increases the heart rate (n = 329, 65.8%), increases blood pressure (n = 330, 66.0%), decreases appetite (n = 303, 60.6%), and causes constipation (n = 299, 59.8%) and that headache is a withdrawal symptom (n = 303, 60.6%).
The attitudes regarding khat use among students
below shows the students’ attitudes towards khat use. Eight of the attitude items (1, 5, 8, 9, 11, 13, 16, and 19) were negatively structured. On average, approximately 23% (ranging from 8.2-31.2%) of the students responded ‘neither agree nor disagree’ to the 20 statements.
Table 5. Attitude on khat use among students (n = 500).
Most of the students reported agreement with statements 2 (47.2%), 3 (64.6%), 4 (64.8%), 5 (50.6%), 6 (79.2%), 7 (61.6%), 8 (43.6%), 9 (44.9%), 10 (52.0%), 12 (48.6%), 13 (40.4%), 14 (64.0%), 15 (60.6%), 17 (47.4%), 18 (53.2%) and 20 (57.8%). Slightly more than three-fifths of the students agreed with the following statements: ‘I will advise people to cease khat use’, ‘Khat chewing is harmful to health’, ‘Children and adolescents should not chew khat’, ‘Khat chewing helps people stay awake’, and ‘Health professionals (HPs) serve as role models for patients and the public’. The students strongly agreed (four-fifths) that ‘Most people in Yemen chew khat’ (item 6).
The students reported disagreement with items 1 (40.4%), 11 (48.6%), 16 (46.4%) and 19 (51.8%). They believed that ‘It is good for health care professionals to use khat’, ‘Khat chewing makes people more popular with their friends’, ‘It is acceptable for HPs to chew khat’, and ‘HPs should not routinely advise patients to cease khat use’.
Discussion
There are several reasons why university students chew khat during study or examination periods. Therefore, gathering information on the knowledge and attitudes of students regarding khat will provide insight into the prevalence of this unhealthy habit among them. Most of the students who participated in this study were male. Many of them lived in urban areas, which indicates the spread of this habit in cities. Approximately half of the students came from large families in which the parents had a low education level. This may be an indication of a low level of awareness and knowledge among parents about the risks of khat chewing, which may be reflected in their children’s knowledge; moreover, managing a large number of children is somewhat difficult and may leave children vulnerable to engaging in unhealthy practices. Many of the students started chewing khat between the ages of 18 and 20 years, which confirms the results of other authors. According to a previous study, khat use was initiated during adolescence (Stevenson, Fitzgerald, & Banwell, Citation1996). One recent study by Gebrie et al. (Citation2018) found that factors such as male sex, family khat chewing habits, friends’ khat chewing habits, alcohol consumption, and cigarette smoking were predictors of khat chewing among university students.
The analysis showed that nearly half of the students used khat; this proportion is considered high for health sciences students, who are supposed to have knowledge about the harmful effects of khat on human health. This result is lower than that in a previous study conducted in 2004 by Laswar et al., in which 54% of participants chewed khat; the differences in the results may be due to the large number of participants in the current study (Laswar & Darwish, Citation2009). Nearly one-fourth of the students in this study used khat daily, and less than one-fifth smoked and chewed khat. However, a previous study analyzed the combination of cigarette smoking and khat chewing, as nicotine in cigarettes has been reported to enhance the stimulating effect of cathinone in khat and to reduce its bitter taste (Kassim, Islam, & Croucher, Citation2011). Both compounds improve mood, increase concentration and decrease anxiety (Kroll, Yusuf, & Fujiwara, Citation2011).
Students preferred chewing khat at gatherings with friends. Approximately two-fifths of the students used khat before examinations due to the expectation that khat will improve their ability to study and memorize information. However, a previous study correlated khat use and poor memorization ability among university students (Colzato, Ruiz, van den Wildenberg, & Hommel, Citation2011). Using khat when studying may have a negative effect on learning ability but has no effect on previously memorized knowledge. This effect is similar to that of amphetamines (Brenneisen, Fisch, Koelbing, Geisshusle, & Kalix, Citation1990).
The average amount of money spent daily on khat was 2000–3000 riyals (approximately USD 8–12). This value is considered high due to the economic downturn and poverty Yemen has experienced since the 2015 war and has a negative impact on the budget allocated for other important aspects of living. Studies in Ethiopia and Somalia reported a similar negative impact of khat chewing on family finances (Griffiths, Citation1998; Mihretu, Teferra, & Fekadu, Citation2017).
Close to one-third of the students considered khat chewing a social habit in Yemen. It has been reported that khat chewing has profound roots in Yemeni culture and society (Al-Mugahed, Citation2008). Other reasons for using khat were to improve concentration, to improve the ability to converse during social gatherings, to increase energy, to enhance academic performance, to improve mental stimulation, to increase vigilance and to increase confidence. These reasons are similar to those reported in another study (Aklog & Tsegay, Citation2013).
Almost half of the participants had knowledge about the addictive property of khat. According to a study conducted in Ethiopia on the effects of khat chewing and cigarette smoking among college students, addiction was at the top of the khat health risk list (Kebede, Citation2002). The first report of khat addiction was in the early fourteenth century (Dillmann, Citation1884), and there is another historical report of khat addiction (Gough & Cookson, Citation1984). A recent report indicated the addictive effect of khat (Kassim & Al'absi, Citation2016). Many people know about khat’s amphetamine-like effect, as one study reported on the similar characteristics of amphetamines and khat (Dhaifalah & Santavy, Citation2004). Approximately half of the students knew that the WHO has classified khat as a narcotic agent and knew that cathinone is the dependence-producing constituent of khat leaves. In 1980, the WHO labeled khat an abused drug, as chronic khat use can result in psychological addiction (Nutt, King, Saulsbury, & Blakemore, Citation2007).
The majority of students recognized the health problems associated with khat chewing, such as tachycardia, hypertension, anorexia, constipation, mental diseases, cardiovascular diseases, hepatitis, cancer, and other withdrawal symptoms. Despite the students’ knowledge of the hazards of khat, most of them still chewed it.
Concerning the attitudes of students regarding khat, it is clear from the results that the general attitude is inconsistent. Students understand the harmful effects of khat on health, and previous studies have shown that Yemeni citizens and Yemeni immigrants in the UK also have a generally inconsistent attitude towards the health and socioeconomic problems caused by khat use (Al-Motarreb et al., Citation2010). The students in the current study agreed that HPs serve as role models for patients and the public, which is compatible with data obtained from a cross-country study carried out in samples of MSs in 48 different countries (Warren, Sinha, Lee, Lea, & Jones, Citation2011). Approximately one-third of the students agreed that it was not necessary to routinely advise patients to quit khat. This finding is similar to that reported in a study of Yemeni MSs at Taiz University (Yi et al., Citation2012). In addition, concerning the students’ attitudes toward khat use by HPs, less than one-fifth strongly agreed and more than one-fourth agreed that it was acceptable. The students’ attitudes are in conflict with their knowledge, but this result can be explained by the association of khat chewing with Yemeni culture and society. When asked about their education on khat in pharmacy or medical school prior to the survey, most of the students said they had participated in education programs, but they still have an inconsistent attitude, further confirming the authors’ conclusions.
In the past, a policy was established to limit the use of khat (Klein, Beckerleg, & Hailu, Citation2009). Nevertheless, the government should develop a program to raise awareness of the harmful effects of khat on health, finances and social life by conducting continuous seminars, training, workshops and education. The program should target not only university students but also primary and secondary school students, as the habit of khat chewing begins during this period and continues as a lifetime habit.
The current study is the first to survey students from all the medicine and health sciences departments in Aden, Yemen; however, similar studies must be conducted in other departments and cities to assess the multiple dimensions of the problem and develop solutions to reduce this habit, which is widespread not only in Yemen but also worldwide (Kassim et al., Citation2011).
Conclusion
Khat chewing is prevalent among Yemeni university health sciences students. There is a lack of knowledge regarding and a positive attitude towards khat use among university health sciences students. Radical solutions must be developed to mitigate the practice of khat chewing and its spread in Yemen; khat use not only negatively affects health but also limits users’ finances and time.
Declaration of interest
The authors declare that they have no conflict of interest. The authors alone are responsible for the content and writing of the article.
Funding
The work was not supported by any funding agency.
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