The following is a summary of “Cannabis Use and CKD: Epidemiological Associations and Mendelian Randomization,” published in the February 2023 issue of Kidney Medicine by Dellepiane et al.

The link between cannabis usage and chronic kidney disease (CKD) has been met with skepticism. Researchers planned to use a large cohort study to examine the correlation between cannabis use and CKD and then use Mendelian randomization and a genome-wide association study (GWAS) to examine the potential for causation. This study looked back at the All of Us cohort data, which totaled 223,354 people. Three genome-wide association studies (N=384,032), including the Psychiatric Genomics Consortium Substance Use Disorders GWAS, the iPSYCH GWAS, and the deCODE GWAS, found genetic instruments for cannabis use disorder. In the CKDGen GWAS (N > 1.2 million), researchers looked at whether or not genetic tools were associated with CKD. Kidney function as measured by cystatin-C and creatinine, proteinuria, and blood urea nitrogen were all indicators of CKD.

Researchers used association analysis to link chronic kief use and chronic kidney disease. Researchers used Mendelian randomization with 2 samples to examine causation. Less frequent users of cannabis did not have a higher risk of CKD in the retrospective research compared to past users (OR, 1.01; 95% CI, 0.87-1.18; P = 0.87), nor did monthly users (OR, 1.15; 95% CI, 0.86-1.52; P = 0.33). The opposite was true for weekly usage: an adjusted odds ratio (OR) of 1.28 for CKD (95% CI, 1.01-1.60) was reported for daily use of 1.25 for CKD (1.04-1.50) and P = 0.04 for daily use of 1.28 for CKD (P = 0.02). Genetic susceptibility to cannabis use disorder was not associated with an elevated risk of CKD in a Mendelian randomization study (OR, 1.00; 95% CI, 0.99-1.01; P = 0.96). Several kidney characteristics and various Mendelian randomization methods did not affect the researcher’s findings. Evidence suggests that cannabis consumption is underreported. Mendelian randomization was used to identify genetic instruments in the GWAS that predominantly included people of European descent. Despite the epidemiological relationship between cannabis use and CKD, there was no evidence of a causal effect, indicating confounding in observational research.

Source: sciencedirect.com/science/article/pii/S2590059522002151