In the EUR data, DSM-NicDep was strongly correlated with the other measures of nicotine dependence (rgs with FTND, PTU, and ICD-TUD ranged from 0.77 to 1.01). The genetic correlations between DSM-NicDep and published GWASs of substance use disorders were of moderate-to-high magnitude: cannabis use disorder (CanUD), problematic alcohol use (PAU), and opioid use disorder (OUD; rg = 0.64 – 0.84). Overall, DSM-NicDep was significantly correlated with 23 of the 26 phenotypes tested (Figure 1; Supplemental Table 5). Compared to the other tobacco-related phenotypes, DSM-NicDep showed the strongest correlations with many traits, albeit with wider confidence intervals due to smaller sample size. When correcting for 24 comparisons, the genetic correlations between DSM-NicDep and smoking initiation, cannabis ever-use, CanUD, and the Townsend deprivation index were significantly larger (p < 0.002) than the corresponding genetic correlations between FTND and these phenotypes.
