There were significant phenotypic correlations between cigarette pack-years and two cortical thickness measures, specifically right lateral occipital gyrus (rP = -0.15, 95% CI = -0.25; -0.04, p = 0.03) and left paracentral gyrus (rP =-0.13, 95% CI = -0.23; -0.02, p = 0.02). These correlations were due to substantial genetic covariances (right lateral occipital = -0.13, 95% CI = -0.26; -0.01, p = 0.03; left paracentral = -0.12, 95% CI = -0.24; 0, p = 0.04). The genetic correlations indicated some overlap between the genetic factors shared between cigarette pack-years and these ROIs (rA = -0.15 and -0.13).
