HRQoL is a widely used instrument for assessing the physical and psychosocial impact of diseases and conditions, and this measure has led to a better understanding of populations’ health and conditions. The SF-36 instrument is one of the most widely used instruments to measure the HRQoL in medical research. Our results showed that the SF-36 was relatively quick and easy to use for the assessment of quality of life of khat chewers. All of the participants managed to complete the SF-36 instrument in a timely manner. The primary finding of this study was that the quality of life score of khat chewers was significantly lower than that of non-khat chewers. In addition, we also found that the physical health perception scores of khat chewers were much higher than the mental health perception scores. This finding indicates that physical harm from khat is less than societal and mental harm, which entails huge disability and discomfort[33, 43]. There are several possibilities that can explain the differences between groups, e.g. 1) people with lower QoL are more likely to become khat chewers (this is a variant of the popular self-medication hypothesis, e.g. Khantzian, 1997, or of the functional use hypothesis, e.g. Boy, Marsden & Strang 2001), 2) an independent third variable (e.g. burden or socioeconomic status) explains why people have lower QoL and higher khat use or 3) Some chemical ingredients in khat might have caused chewers to report lower levels of quality of life.
We found that khat chewers were characterized by low socioeconomic conditions; similar to other types of substance abuse, but this was not the case in non-khat chewers (Table 2). The variables of education, age, employment status, and marital status were negatively associated with khat chewing. This suggested that the odds of being khat chewers were minimal among older respondents, and those with a good employment status and higher education level. However, respondents less than 35 years, who were unmarried, had inactive employment and a lower education level, had higher odds of being khat chewers. More than 70% of khat chewers were younger than 35 years, and the unemployment rate was 62% among khat chewers. This is in accordance with the opinions reported by other studies, which have reported that excessive khat use is associated with reduced productivity and risk of unemployment because khat reduces motivation of work and increases the occurrences of work absenteeism[8, 46, 47].
Moreover, khat chewing was reported as a main source of family problem that reduces the quality of life of the spouses; this could be explained by the following reasons: First, khat is usually chewed in group sessions and takes long hours (6 hours per session) of chewing with friends and colleagues. This habit routinely causes the chewer to neglect their families and consequently prompts conflict with the spouse. Second, money spent on khat purchases can also cause conflict between spouses. Third, sleeping problems that are often associated with khat chewing severely affects working hours and consequently reduces family income. Finally, the emotional instability, mood swings and the bad temper associated with khat chewing can cause the chewer to be violent and aggressive towards the spouse.
Socioeconomic variables play a large role in shaping the characteristics of individuals. People with a higher socioeconomic status are less likely to be involved in regular use of substances and drugs compared with people with lower socioeconomic status[49–51]. Some studies have reported that migrant khat chewers in Europe and North America are culturally isolated and are in miserable socioeconomic situations[52, 53]. In the general literature, socioeconomic status is often characterized as a root cause of health inequalities and health risk factors; primary prevention activities, such as increasing law enforcement efforts and community-based interventions focusing on social networking and improving the socioeconomic conditions, may help change khat chewing behavior or prevent potential khat users from indulging in khat chewing. Law enforcement interventions are among the most frequent policies to fight with substance abuse habits; and in our opinion this intervention can at least stop the spread of khat chewing from lower socio-economic class to the higher socio-economic class.
Previous studies have reported that substance users (i.e., alcohol and opiates) have lower HRQoL than the general population[55–60]. The Mann–Whitney test indicated that the mean rank scores of the two groups were significantly different from each other. The HRQoL scores of khat chewers in this study were relatively low (indicating a worse perception of HRQoL) compared with the non-khat chewers, especially for VT, RE, and SF. The difference in mean between the two groups gets smaller in the dimensions of BP, PF, and GH. This indicates that societal and mental health burden due to khat chewing is comparatively higher than the physical harm due to khat chewing; this can be explained by that khat is sometimes associated with mental health problems, such as depression, paranoia, hallucination, manic behavior, hyperactivity, and some other mental disorders[61–66].
The relatively close scores of physical health of khat and non-khat chewers showed less impairment of khat chewing in the physical and functioning dimensions compared with emotional and social function. These findings are consistent with results of other similar studies on alcoholics[56, 67]. Finally, the Cronbach alpha coefficients indicated good internal consistency, with values generally higher or equal to 0.70, and these results were similar to those described in other studies[55, 57], but were lower than those recommended in the literature (i.e., between 0.85 and 0.95)[42, 67]. These findings indicated that the SF-36 instrument was a good tool for the purposes of this study.
Limitations and future research implications
Similar to other self-reported questionnaires, this study was subject to recall bias of patients and selection bias of medical centers. Additionally, instead of using a generic instrument (SF-36 questionnaire) it may be more appropriate to use a specifically designed instrument for the effects of khat. The sample representativeness is questionable; meaning any inferences from this study population to the whole population was not appropriate. The HRQOL was not verified in this study with medical records, which could have added value to results. Tobacco smoking was not investigated; this could have confounded the results. The social desirability in this study may have been eliminated through using the self-administered questionnaire though we do not know the number of participants who self-administered questionnaires and those who provided data through face to face interviews. The implication of this study for future research with respect to validation of these study findings and answering relevant questions that include the health economic impacts (cost analysis) of khat chewing is appropriate to be reported within the discussion. Future research is to consider data from female khat chewers as well.
Measuring the quality of life is a broad topic and it is impossible to form a definite conclusion as to why non-khat chewers had higher rates of physical and mental health compared with their khat chewing counterparts. Some chemical ingredients in khat might have caused chewers to report lower levels of quality of life. Another possibility is that users with a low quality of life use khat more frequently. These possibilities need to be explored further, and could be a focal point for future studies.