Most of the studies discussed have focused on isolated SUDs or depressive disorders. To date, only one study has directly compared glial cell pathology in subjects with comorbid depressive symptoms of escalating severity, alcohol dependence alone, and an MDD cohort from an earlier study by the same group (Miguel-Hidalgo et al. 2002). In this study, subjects with a history of alcohol dependence and depressive symptoms (n = 8) had decreased dlPFC glial cell density compared to subjects with alcohol dependence and no depressive symptoms (n = 9) and the historical MDD group (n = 12) (Miguel-Hidalgo et al. 2002).This suggests that subjects with comorbid depression and alcohol dependence may have even more severe glial cell dysfunction than in either illness alone.
