Influence of the donor history of tobacco and marijuana smoking on early and intermediate lung transplant outcomes.

BACKGROUND Donor smoking histories are common in the lung donor pool, which are known to adversely affect post-lung transplant (LTx) outcomes. However, no evidence is available about smoking status (current/former), cumulative dose effect, or the combined effect of tobacco with marijuana. METHODS We retrospectively reviewed our local state-based donation organization records and subsequent LTx recipient outcomes. The primary outcome was 3-year graft survival, with cause of death as secondary outcomes. Univariate and multivariate Cox regression analyses were used to explore smoking status or cumulative dose effect. RESULTS Between 2014 and 2018, 304 LTxs were performed: 133 (44%) LTxs were from never-smoker donors, 68 (22%) from former-smoker donors, and 103 (34%) from current-smoker donors. Of the current-smoker donors, 48% had a marijuana use history. There was no significant difference in early mortality, although recipients who received transplants from current-smoker donors had a lower 3-year graft survival than those who received transplants from never smokers. Multivariate modeling showed that current tobacco smoking (hazard ratio: 2.13, 95% CI: 1.13-3.99) and a more than 5-year weekly marijuana use (hazard ratio: 2.97, 95% CI: 1.29-6.87) were independent donor factors affecting graft survival. Chronic lung allograft dysfunction accounted for a higher proportion of the causes of death within 3 years after LTx where lungs from current/former smokers were utilized compared with those from never smokers (chronic lung allograft dysfunction-cause mortality: 11%, 7%, 0%, respectively). CONCLUSIONS More than 50% of LTx donors had smoking histories. Current tobacco use or more than 5-year weekly marijuana smoking history adversely affected 3-year graft survival. Our findings support the importance of obtaining a detailed donor tobacco and marijuana smoking history.