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.