• Systematic Review on the Relationship Between Marijuana Use

      Janousek, Alyssa; The University of Arizona College of Medicine - Phoenix; Campos-Outcalt, Douglas (The University of Arizona., 2013-03)
      Objective: To develop a systematic review on the association between marijuana use and cyclic vomiting sydrome for the Arizona Department of Health Services. The review attempted to answer the key question of whether there is an association between marijuana use and cyclic vomiting syndrome and if so, whether marijuana use causes cyclic vomiting syndrome. Methods: The databases MEDLINE (PubMed), The Chocrane Library, CINAHL (EBSCO), psycINFO, Web of Science, and Google Scholar were searched for the topics of marijuana use and cyclic vomiting syndrome multiple times from September 2012 – November 2012. The quality of each pertinent study was assessed by two reviewers. Case-control and cohort studies were assessed using the Newcastle-Ottowa Assessment Scale.45 Case series’ were assessed using the criteria laid out in Guise et al.’s systematic review which was adapted from Deeks et al. and Agency for Healthcare Research and Quality.15,11,1 Literature reviews were assessed using the AMSTAR criteria.35 Overall quality of evidence and causation were determined using the GRADE methodology and the Bradford Hill criteria, respectively.16,18 Results: A total of 95 articles were identified and 37 of these were found to address the key question in some way. The study designs of identified articles were 1 case-control study, 3 cohort studies, 4 case series, 24 case reports, and 5 literature reviews. The majority of reviewed studies report an association between marijuana use and cyclic vomiting syndrome or cannabinoid hyperemesis syndrome with marijuana use preceding the onset of vomiting symptoms. However, the overall body of evidence reviewed is of very low quality and does not meet criteria to demonstrate causation. Significance: The majority of reviewed studies suggest an association between marijuana use and cyclic vomiting syndrome or cannabinoid hyperemesis syndrome though no studies suggested any evidence as to whether marijuana use causes cyclic vomiting syndrome or cannabinoid hyperemesis syndrome. The entire body of evidence reviewed, however, is of very low quality and therefore no definitive conclusions can be drawn from this review about the association between marijuana and cyclic vomiting syndrome or whether marijuana use causes cyclic vomiting syndrome.