Cannabis and Cigarette Use Before and After Living Kidney Donation

BACKGROUND: It is unclear whether kidney donation leads to lifestyle changes in terms of cannabis and cigarette use. OBJECTIVE: To describe cigarette and cannabis use before and after kidney donation and to determine their associations with lifestyle and clinical factors. DESIGN: Retrospective cohort study. SETTING: The Living Kidney Donor program in the Champlain Local Health Integration Network at The Ottawa Hospital in Ottawa, Canada. PATIENTS: The study included 178 living kidney donors who donated between January 2009 and December 2018. MEASUREMENTS: Donors were screened for cannabis and cigarette use by telephone interview. Their clinical characteristics and changes in kidney function before and after donation were recorded. METHODS: Cannabis and cigarette use before and after kidney donation were compared using chi-square test. Risk factors associated with their use was examined by univariate and multivariate logistic regression. Wilcoxon rank sum test was used to examine the association of cannabis and Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI) estimated glomerular filtration rate (eGFR) at donation and at last follow-up. T-test was used to examine the association of cigarette smoking and CKD-EPI eGFR at donation and at last follow-up. RESULTS: Among 305 donors, 262 met inclusion criteria and 178 participated (mean of 4.7 ± 2.9 years from kidney donation). Cannabis and cigarette use were reported by 5% (9 of 178) and 13% (23 of 178) at donation. After donation, 8% (14 of 178) and 5% (9 of 178) started cannabis and cigarettes, respectively; 74% (17 of 23) of smokers remained smokers after donation and 88% (53 of 60) who quit smoking before donation did not restart after donation. In multivariate analysis, non-married/common-in-law status was associated with cannabis use (odds ratio, 2.73; 95% confidence interval, 1.05-7.11; P = .04). There was no difference in eGFR pre- or post-donation among cannabis or cigarette users. LIMITATIONS: The single-center study design limits generalizability. Social desirability bias may have affected survey responses and cigarette smoking was not quantified. CONCLUSIONS: Cannabis and cigarette use was uncommon in the studied population and was not associated with remaining kidney function. Cannabis use increased post-donation. Most smokers remained smokers after donation and most donors who quit smoking before donation did not restart after donation. This warrants education and support for potential donors who smoke, to quit smoking prior to donation to reduce risks of cardiovascular and end-stage kidney disease. TRIAL REGISTRATION: Not applicable as this is not a clinical trial.