Khat chewing habit as a possible risk behaviour for HIV infection: A case-control study

Background: The use/abuse of psychoactive drugs such as khat leaves (Catha edulis) are believed to alter one’s moods or emotional state either through the sustained release or inhibition of neurotransmitters, thereby enhancing or dampening the response of the individual. Most people whose thinking are warped by continued drug use may not be able to see the harm resulting from their actions. Thus, there has been a strong linkage between drug use and casual or unsafe sexual practice despite the serious concern about HIV infection. Objective: Khat chewing is known to be a widespread habit in Ethiopia. This study is, thus, aimed at investigating whether or not the use of this psychostimulant alone or in conjunction with other behaviors associated with its use constitutes a risk behavior that accelerates the spread of HIV infection. Methods: A case-control study involving 850 human subjects, i.e. 425 HIV positives (cases) and 425 HIV negatives (controls) was conducted using rapid test algorithm and/or western blot method for determination of HIV status. Both groups were interviewed about their probable khat chewing habits, alcohol intake, multiple sexual practice, and the like, using a structured questionnaire. The data were analysed using SPSS/PC + statistical software. Results: Risk behaviors for HIV infection such as khat chewing in conjunction with alcohol intake and casual sex were observed more in people with HIV than in the control group. Khat chewing was significantly associated with multiple sexual practice (OR = 4.03, 95% CI = 3.02, 5.39), which in turn was strongly linked with HIV cases (OR = 3.52, 95% CI = 2.64, 4.69). Thus, more than the non-chewers, khat chewers constituted significantly higher number of HIV cases (OR =2.32, 95% CI = 1.75, 3.07). Conclusion/Recommendations: Khat chewing is a risk behavior for the spread of HIV infection. Mainstreaming of khat control into national development planning initiatives is recommended. [Ethiop.J.Health Dev. 2005;19(3):174181] Introduction For over 1400 years, the chewing of fresh leaves of Catha edulis Forssk., variously referred to as khat, chat, Abyssinian tea, etc. as a stimulant/euphoriant has been practiced in the Middle East, Somalia, Ethiopia and extending down to as far as the Cape in South Africa (1). Up until a few decades ago, khat chewing was mainly restricted to older men or members of Muslim communities who used it in lieu of alcohol on religious grounds and, therefore, the habit did not pose serious public health or socio-economic problems (2). In recent years, however, its use has spread across many faiths, ethnic groups, age, sex, etc. (3). The ever spreading recourse being made to euphoriants and/or stimulants like khat and other psychotropic substances may, thus, be attributed to many of the socio-economic and political upheavals, such as recurrent drought, famine, civil strife, and the spectre of the HIV/AIDS epidemic. Recent trends indicate that by and large khat chewing has become a pastime activity resulting in the consumption of large quantities of the stimulant with serious consequences on the health and socio-economic conditions of communities (4, 5, 6, 7). For example, clinical pictures of behavioural disturbances induced by khat chewing have been reported by several workers (1, 8, 9, 10). The consumption of fresh khat leaves causes the release of the active constituent, cathinone, which causes sympato-mimetic effects and induces symptoms such as euphoria and hyperactivity. Cathinone has analogous mechanisms of action with pharmacological properties that are reminiscent of those induced by amphetamine, i.e. anorexia as well as hypermotility (11). In fact, it is now being referred to as a “natural amphetamine” and its effects in animals correspond with those observed in khat using humans (6). The World Health Organization not only considers the wide-spread habit of khat chewing as pharmacologically equivalent to amphetamine abuse, but it has also included cathinone in its list of controlled drugs (12, 7, 6). Similarly, khat use in many European countries and Canada has been restricted or made illegal and is as such classified as a controlled substance. In the United States, the Drug Enforcement Agency (DEA) has asserted that the plant itself, Catha edulis, is a Schedule I substance on a par with opiates for the period it has cathinone in it, i.e. within the first 48 hours of harvest (13). Some advocates of khat, however, allege that khat leaf is rich in ascorbic acid and, therefore, the undesirable side effects of khat chewing are minimal. Of course, by modulating catecholaminergic activity or transmission of dopamine, ascorbic acid acts as an antidote to the effects of amphetamine (14, 15). However, this occurs assuming that there is adequate quantity of ascorbic acid in the leaf, Khat chewing habit as possible risk behaviour for HIV infection 175 ______________________________________________________________________________________ Ethiop.J.Health Dev. 2005;(3) and if it could ever be released from the leaf matrix by mastication and becomes bio-available. In light of WHO's recommendation, the problems associated with khat chewing for the moment should be considered in a manner similar to amphetamine abuse (12, 7, 6). Hence, it is the psychotropic and mind altering drug type whose use could possibly constitute a risk behaviour in the amplification of the HIV/AIDS epidemic in countries like Ethiopia, where the habit is widespread. Furthermore, different varieties of khat are perceived to enhance sexual arousal among khat chewers. This was corroborated by pharmacological tests in male experimental animals that were administered with oral treatment of cathinone though there is still no evidence that the resulting increased sexual activity is accompanied by erectile and ejaculatory responses (16). The overwhelming evidence, however, suggests that the habit causes a high frequency of spermatorrhoea and decreased libido and, at a latter stage, impotence as observed in Somalia and Djibouti, where as high as 60% of the male chewers in those countries were reported to be impotent (7, 17, 4). Whether khat chewing induces excessive sexual arousal, impotence or spermatorrhoea, the end result of the habit is believed to lead to strained relations between spouses or married couples and most likely to precipitate family fragmentation and/or multiple sexual practices. Khat chewing habit, may thus be postulated as one of those risky behaviors that could fuel the spread of HIV. In this regard, a link has been shown to exist between khat use and increased exposure to HIV/AIDS among prostitutes in Djibouti (18). Insomnia is a common problem associated with the use of khat which prompts the chewer to use/abuse sedatives and to indulge in alcohol as a means of overcoming the side effect (18, 4, 10, 19). As such unplanned or unsafe sex and hence the risk of exposure to HIV under such heavy influence of a combination of drugs could not be an unlikely scenario. Therefore, it can be surmised that khat chewing habit, like many other drugs of abuse could constitute risky behaviour contributing to the spread of HIV infection (20). Though khat chewing in Ethiopia is a common practice, there are, however, no studies reflecting the possible existence or, for that matter, non-existence of a link between the chewing habit and the HIV epidemic. Such studies could prove essential in the effectiveness of HIV prevention programs which critically depend on the extent to which they reduce the risk behaviour of those most likely to contract and spread the virus. The aim of the present study is therefore, to determine whether or not khat chewing alone or in combination with other behaviours associated with khat chewing constitute possible risk factor(s) in the spread of the HIV/AIDS epidemic in Ethiopia. Methods Study Sites: The study was conducted in 17 voluntary counselling and testing (VCT) centres found in the Southern Nations Nationalities and Peoples Region and the Oromia Regional State of Ethiopia between March 2003 and May 2004. The VCT centres where the study was conducted were: Adama Hospital (Adama Town), Atat Hospital (Atat wereda), Bushilo Catholic Health center (near Awassa Town), Dilla Hospital (Dilla Town), Hosana Hospital (Hosana Town), Kuyera Hospital (Kuyera Town), Weliso Catholic Hospial (Weliso Town), Yirgalem Hospital (Yirgalem Town); Bedele Health Centre (Bedele Town), Dukem Health Centre (Dukem Town), Mojo Health Centre (Mojo Town), Shashemene Clinic (Shashamane Town); Bethzatha Clinic (Adama town), branches of the Family Guidance Association of Ethiopia in Jimma, Adama, and Ziway towns and Marry Joyce in Awassa Town. The regions and the VCT centres were selected based on their high production, widespread use and trade in khat. Study design: In order to examine whether khat chewing constitutes a statistically valid risk behaviour for exposure to HIV infection, an unmatched case-control study was conducted involving 850 human subjects, i.e. 425 HIV positives or cases, and 425 HIV negatives or controls as determined by a rapid test algorithm and/or western blot. Controls were required to assess why they were negative, while their counterparts are positive, i.e. what do they do that the cases don’t or what is that they don’t do, but the cases do. Sample size calculation: Taking a 95% confidence interval (CI), 80% power and assuming exposure among controls to be 49.83% with an odds ratio (OR) of 1.49, the minimum sample size required was found to be 421 according to the statistical calculation programme in Epiinfo version 6. Selection criteria of study subjects: The subjects selected were those that showed up voluntarily for HIV testing at the VCT centres and were tested either positive or negative for HIV. Their agreement to respond to questions relating to their probable khat chewing habit and the associated behaviors was taken as an additional selection criterion. Sampling technique: Each of the 17 VCT centres were provided with 50 copies of the questionnaire, 25 each for case and control subjects who showed up consecutively on their own free will and agreed to cooperate to respond to the issues set out in the questionnaire. Verbal consent of all the 850 subjects who presented themselves to the various VCT centres was thus obtained before 176 Ethiop.J.Health Dev. ______________________________________________________________________________________ Ethiop.J.Health Dev. 2005;(3) administering the pre-tested structured questionnaire. The HIV status of the study subjects was taken as the dependent variable, while khat chewing habit was used as the key independent variable. Other major issues included in the questionnaire were multiple sexual activity and alcohol consumption. The interviewers were trained HIV counsellors, mostly nurses and physicians working as permanent employees of the respective VCT centres. The counsellors were given orientation by the investigators of this study on how to fill out the questionnaire in consultation with those tested HIV positive (cases) and negative (controls) after blood test was undertaken in the selected centres. All cases and controls at or above the age of 16 years were included for the interview, while those below this age were excluded. Ascorbic acid quantification in khat leaf: Ascorbic acid, a well known antidote against amphetamine and amphetamine-like substances, was reported to reach as much as 325mg/100g leaf of khat (21). In view of this a quantitative laboratory analysis of ascorbic acid was conducted in this study on the leaves of the six most popular local varieties of khat by adhering to standard phytochemical methods ( 22). Data Analysis: Data were entered and analysed using SPSS/PC+ statistical software. The bivariate analysis was used to calculate the crude odds ratio (OR) and a 95% confidence interval (CI). For all statistical significance tests, the cut of value set was p<0.05 as this was considered statistically reliable for analysis of such a study. Since crude OR does not take into account the effect of the confounding variable(s), a multivariate analysis was employed by fitting the logistic regression. Thus, HIV status was inserted as a dependent variable, while khat chewing was taken as a key independent variable along with other influencing factors, viz. age, sex, religion, address, educational status, marital status, alcohol consumption, and recourse to multiple sexual practice. Results The study population consisted of 850 individuals. More than 73% of the respondents were in the age group of 1630 years and most (56.7%) were males. The unemployed and those with primary or less level of education made up 52% and 54.5% of the study subjects, respectively. The unmarried constituted the greater proportion of the respondents as did the Christians and urban residents. The rate of khat chewing was found to be 41% among the controls and as high as 59% among the cases. An identical rate was observed with respect to alcohol consumption. Sixty three percent of the HIV cases resorted to multiple sexual practices, compared to only 37% of the controls. Females comprised of a significant proportion of the HIV cases compared to males (p<0.005) [OR = 1.48, 95%CI =1.12,197]. Significantly higher HIV cases were observed among the age group at or above 31 years than those between 16-30 years, among those with primary or lesser levels of education more than those with secondary or higher levels, the married more than the singles, among khat chewers than in the non chewers, and among those who consumed alcohol, and resorted to multiple sexual practice (p<0.05). Although the percentage of HIV cases was higher among the Christians more than the Muslim subjects in this study, the difference was not found to be statistically significant (p>0.05) [Table 1]. In the present study population, HIV cases constituted 50%. In the stratified analysis for khat chewing, chewer controls indulging in alcohol were 37%, while HIV cases comprised 63%. HIV cases who chew and subsequently resorted to multiple sexual practice constituted 68%, while the rate was as low as 32% among the chewer controls. Chewers invariably constituted greater percentages of HIV cases than the non chewers (p<0.03). It appears thus that khat chewing on its own right is a risk factor for higher rate of incidence of HIV cases though there is no significant difference between chewers or non chewers among the HIV cases of the age group at or above 31 years, rural residents, married once and those who did not engage in multiple sexual practice (p>0.05). Alcohol consumption and khat chewing are significantly associated, p<0.001 [OR = 5.33, 95% CI = 3.96, 7.18]. There were significantly higher HIV cases among khat chewers who subsequently or concurrently indulged in drinking alcohol than in non chewers, but boozers, p<0.001 (OR = 2.19, 95% CI = 1.39, 3.44). The percentage of HIV cases was significantly higher among female chewers than non chewers, and among male chewers than in their non chewer counterparts (p<0.03). Despite the higher percentage of HIV cases among chewers, the difference, however, was not significant between chewer or non chewer males who are: at or above 31 years, at primary or lesser levels of education, and those who do not engage in multiple sexual practices; among chewer or non chewer males and females who are: muslims, rural residents and married people (p>0.05). Multiple sexual practice was higher among chewer males than in non chewer males, p<0.004 [OR = 2.18, 95% CI = 1.28, 3.71]. A similar difference was also observed in female chewers compared to non chewers, p<0.009 [Or = 2.40, 95% CI = 1.24, 4.62]. The rate of khat chewing and subsequent recourse to multiple sexual practice was much lower among the control group than in the HIV cases. The outcome of the final regression model indicated that three variables, i.e., address, occupation and alcohol consumption were dropped. Khat chewing habit, however, emerged as a significant risk predictor for HIV Khat chewing habit as possible risk behaviour for HIV infection 177 ______________________________________________________________________________________ Ethiop.J.Health Dev. 2005;(3) infection along with other influencing factors, viz. age, sex, religion, educational and marital status, and multiple sexual practice. In light of this analysis, the risk of being HIV positive increases 1.97 times by khat chewing; by as much as 4.68 times through multiple sexual practice; by 2.05 times among the age group at or above 31 years; and by 2.71, 2.67, 2.09, and 1.62 times among the females, the less educated, among the married, and the Christians, respectively. These differences are all statistically significant (p<0.021). The result of the crude and adjusted OR is shown in Table 2. The result of the quantitative determination of ascorbic acid during this study demonstrated the amount for the six local varieties of khat to be far less than 1mg/100g of leaf. Table 1: Frequency of HIV case and control study subjects by socio-demographic characteristics in VCT centers 2003-2004. Number of HIV Variable Cases (%) Controls (%) OR (95% CI) P-value