Impact of donor smoking history on kidney transplant recipient outcomes: A systematic review and meta-analysis
Christie Rampersad1,2, Jason Bau3, Ani Orchanian-Cheff4, S. Joseph Kim1,2.
1Ajmera Transplant Centre, Toronto General Hospital, University Health Network, Toronto, ON, Canada; 2Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada; 3Department of Medicine, Division of Transplant Medicine, University of Calgary, Calgary, AB, Canada; 4Library and Information Services, University Health Network, Toronto, ON, Canada
Background: Impact of donor smoking history on kidney transplant recipient outcomes is undefined.
Methods: We systematically searched, critically appraised, and summarized associations between donor smoking and primary outcomes of death-censored and all-cause graft failure (DCGF, ACGF), and secondary outcomes of allograft histology, delayed graft function, serum creatinine, estimated glomerular filtration rate, and mortality. We searched MEDLINE, Embase, and Cochrane Databases from 2000-2023. Risk of bias was assessed using Risk of Bias in Non-randomized Studies – of Exposure tool. Quality of evidence was assessed by Grading of Recommendations Assessment, Development and Evaluation Working Group recommendations. We pooled results using inverse variance, random-effects model and reported hazard ratios for time-to-event outcomes or binomial proportions. Statistical heterogeneity was assessed with I2 statistic.
Results: From 1785 citations, we included 17 studies. Donor smoking was associated with modestly increased DCGF (HR 1.05 (95% CI: 1.01, 1.09); I2 = 0%; low quality of evidence), predominantly in deceased donors, and ACGF in adjusted analyses (HR 1.12 (95% CI: 1.06, 1.19); I2 = 20%; very low quality of evidence). Other outcomes could not be pooled meaningfully.
Conclusions: Kidney donor smoking history was associated with modestly increased risk of death-censored graft failure and all-cause graft failure. This review emphasizes the need for further research, standardized reporting, and thoughtful consideration of donor factors like smoking in clinical decision-making on kidney utilization and allocation.
CR is supported by a Kidney Research Scientist Core Education and National Training Program (KRESCENT) salary award co-funded by the Kidney Foundation of Canada, the Canadian Society of Nephrology, and the Canadian Institutes of Health Research (CIHR). The funders had no role in defining the content of this article.
[1] Kidney Transplant
[2] Smoking
[3] Cigarette
[4] Tobacco
[5] Graft failure
