Table 1. Studies reporting on the illicit drug use among solid-organ transplant candidates and those who received transplants.

ALD: alcoholic liver disease; HCV: hepatitis C virus, IDU: injecting drug use

Study/ year	Type of study	Sample size	Type of transplant	Results
Stark, (2019)	Retrospective cohort study	2067	Kidney	3% met criteria for cannabis abuse or dependence, 58% of them were daily users, 31% had other illicit drug dependencies
Schult, (2019)	Cross-sectional study, consecutive sample hospitalized 3 months after transplant	190	Liver	In the overall cohort, any illicit drug was used by 35% at some point in time, most frequently cannabis (31%), amphetamine (16%), heroin (5%), cocaine, inhalants, and hallucinogens (8% each)
Alhamed, (2019)	Database linking national kidney transplant records with Medicare claims	52,689	Kidney	Prevalence of cannabis abuse or dependence was diagnosed in 0.5% in the years before and (0.3%) after transplant
Kotwani, (2018)	Retrospective cohort of candidates listed for a liver transplant	884	Liver	Prevalence of cannabis use- 48%, recent use at the time of transplant evaluation- 7%, among marijuana users 13% had weekly use and 16% daily use 46% had a history of illicit drug use with 14% being recent users
Sacco, (2018)	Survey among liver transplant candidates with alcoholic liver disease	67	Liver	(47.8%) used illicit substances prior to transplant and 16.4% reported illicit drug use post-transplant
Tang, (2018)	Single‐center, retrospective, cohort study	2280	Kidney	Prevalence of current substance use- 17%, current tobacco use- 14%, current drug use- 5%; historical drug use 15%, majority of current (67%) or historical (54%) used cannabis
Lamba, (2012)	Cross-sectional descriptive using a mailed questionnaire	281	Liver	29% had a history of substance or alcohol use
Webzell, (2011)	Cross-sectional assessment of recent substance use among liver transplant candidates	109	Liver	Screen positivity was more common among patients with HCV (40%) and ALD (38%) versus patients with other liver diseases (18%). ALD patients most frequently had positive results for opiates (20%), benzodiazepines (15%). 20% of HCV patients had a positive screen for cannabis. Overall, ALD and HCV patients were more likely to have positive urine toxicology results (38%, 40%, and 18% positive, respectively), 4% of patients with ALD or HCV self-reported current alcohol or illicit drug use Positive urine toxicology screen in 30% of the participants. 29% of males and 33% of females had positive toxicological results 2% of patients had 3 substance use classes and 8% had 2 substance use classes
Gottardi, (2010)	Past injection drug users using data source of transplant registries of the University Hospitals	59	Liver	4.6% of transplanted patients had a history of IDU Everyone used heroin 14% also used cocaine and 13.6% also consumed other illicit drugs such as marijuana, LSD, 16.9% of the patients had a substitution therapy before and 6.8% continued substitution therapy after liver transplant
Ranney, (2009)	Retrospective cohort study	1489	Liver	10.4% (155 patients) were cannabis users during liver transplant evaluation period Marijuana users were mostly males and younger 31% of marijuana users also had a positive urine screen for narcotics, 21.9% had benzodiazepines, and 7.7% had other substances
Gedaly, (2008)	Retrospective chart review of alcoholic liver disease patients requiring a transplant	147	Liver	47.4% had previous or current use of one or more substances 17.2% continued to have objective evidence of illicit drug use post-transplant marijuana use amongst 28.5%, cocaine among 16.1%, IV drug use among 15.3%, and narcotic use among 17.5% of participants. Substance use after transplantation was marijuana 13.9%, cocaine 3.5%, and amphetamines 0.7% of the population
Hanrahan, (2001)	Retrospective data analysis	189	Heart	24.86% had a history of substance use pre-transplant
Shapiro, 1995	Prospective study	125 consecutive sample	Heart	20.3% with a past substance use history and 5.4% had a recent substance use history at the time of evaluation