Cannabis use does not impact on type 2 diabetes: A two‐sample Mendelian randomization study. (12th February 2021) - Baumeister, Sebastian‐Edgar
Abstract: Cannabis has effects on the insulin/glucose metabolism. As the use of cannabis and the prevalence of type 2 diabetes increase worldwide, it is important to examine the effect of cannabis on the risk of diabetes. We conducted a Mendelian randomization (MR) study by using 19 single‐nucleotide polymorphisms (SNPs) as instrumental variables for lifetime cannabis use and 14 SNPs to instrument cannabis use disorder and linking these to type 2 diabetes risk using genome‐wide association study data (lifetime cannabis use [ N = 184, 765]; cannabis use disorder [2387 cases/48, 985 controls], type 2 diabetes [74, 124 cases/824, 006 controls]). The MR analysis suggested no effect of lifetime cannabis use (inverse‐variance weighted odds ratio [95% confidence interval] = 1.00 [0.93–1.09], P value = 0.935) and cannabis use disorder (OR = 1.03 [0.99–1.08]) on type 2 diabetes. Sensitivity analysis to assess potential pleiotropy led to no substantive change in the estimates. This study adds to the evidence base that cannabis use does not play a causal role in type 2 diabetes. Abstract : The causal relevance of cannabis use as a risk factor for diabetes is unclear based on traditional observational studies. By considering the relationships between genetically predicted values of lifetime cannabis use and cannabis use disorder and type 2 diabetes within a two‐sample instrumental variable framework that is less influenced by environmental confounding, we found that cannabis use does not affect diabetes.