The prevalence and pattern of cannabis use among patients attending a methadone treatment clinic in Nairobi, Kenya

Cannabis is the most widely used illegal substance in the world, with a global prevalence of 4% among people aged 15 to 64 years and a recent trend of growing use. Cannabis usage can have negative health consequences, such as impaired neurodevelopment, an increased risk of addiction and other drug abuse, cognitive impairment, low educational attainment, and an increased risk of mental disease, such as psychosis, depression, and anxiety disorders. Cannabis usage during methadone therapy may have a negative influence on the success of the treatment. The purpose of this study was to find out how common cannabis usage was among patients in a methadone treatment clinic in Nairobi, Kenya.

The research was carried out at the MMT clinic at Mathari National Teaching & Referral Hospital (MNTRH), which was Nairobi's first publically financed and university-sponsored MMT clinic. From December 2014 to November 2018, 874 individuals on methadone treatment were studied retrospectively. Patient files were examined for information on sociodemographic variables and drug use trends based on urine drug testing. Statistical Package for the Social Sciences (SPSS) was used to examine the data.

Point prevalence of cannabis use was 85.8% (95% CI, 83.3 – 88.0) at baseline and 62.7% (95% CI, 59.5 – 65.8) throughout follow-up. Opioids, cannabis, and benzodiazepines were the most often utilized medications in a polysubstance use pattern. The patients' mean age was 35.3 (SD 9.0) years, with the majority of them being male, unemployed (76%) with just a primary level of education (51.4%) and divorced or separated (48.5%). University degree was linked to a lower incidence of cannabis usage (OR = 0.1, 95 % ci: 0.02-0.8, p = 0.031).

There is a high point prevalence of cannabis use during treatment intake and follow-up among individuals with opioid use disorder on methadone treatment. There is also a pattern of polysubstance usage. Continuous cannabis use screening and monitoring among MMT patients is critical for identifying individuals who use cannabis and then providing appropriate and focused treatments to improve treatment results. As people continue to use the MMT, there is also a need for programs that target other drug abuse.