“…Alcohol dependence has been related to higher delay discounting rates in young-to-middle adulthood (Petry, 2001; Vuchinich & Simpson, 1998); although Kirby & Petry (2004) revealed no significant difference in delay discounting between alcohol users and controls. A significant association of delay discounting with different tobacco outcomes has been substantiated in the literature, including tobacco use frequency and quantity (Amlung et al, 2017; Ohmura, Takahashi, & Kitamura, 2005; with some exceptions, e.g., Sweitzer et al, 2008), and nicotine dependence (Amlung & MacKillop, 2014; Mackillop & Tidey, 2011; Sweitzer et al, 2008). Opioid use was also related to delay discounting, with heroin users demonstrating significantly higher delay discounting rates than non-users (Kirby et al, 1999; Madden et al, 1997; MacKillop et al, 2011).…”