Cannabis and negative tuberculosis treatment outcomes association: a systematic review and meta-analysis

Abstract

Introduction: Tuberculosis (TB) is a global public health problem with still high mortality rates. Poor treatment adherence and loss to follow-up were described in persons with TB and cannabis consumption and might be related with TB transmission and unfavorable treatment results. We performed a systematic review and meta-analysis with the aim to evaluate the association between cannabis use and unfavorable TB treatment outcomes (defined as death, loss to follow-up, or treatment failure).

Methodology: A systematic review was carried out in Pubmed, Biblioteca Virtual de la Salud (BVS), Cochrane Central Register of Controlled Trials, and Scopus, using the terms: “tuberculosis”, “cannabis use”, among others. Cohorts, case-control, and cross-sectional studies published until December 31, 2020, were considered. We include studies that involve persons with TB diagnosis, cannabis use, and TB treatment outcomes.

Results: A total of 246 studies were found and 7 were included for the final analyses. No study matched the definition to be included in the main analysis which was unfavorable treatment outcome(death, loss to follow up or failure). A secondary analysis of 3 studies showed a positive association between cannabis use and loss to follow-up (OR = 5.3; 95% CI: 3.79 - 7.50). All studies included were evaluated as high quality.

Conclusions: Cannabis use was found to be associated with loss to follow up; however, more evidence including studies designed to specifically measure this association is needed to further understand the role of cannabis use during TB treatment and its interactions with the use of other substances and mental disorders.