8‐oxo‐dG levels in the caudate and putamen from patients with diseases [Parkinson disease (PD): n = 10, Parkinson disease dementia (PDD): n = 7, dementia with Lewy bodies (DLB): n = 10, Alzheimer's disease (AD): n = 26] and age‐matched controls ( n = 10). Value shown are means ± SEM as the concentration of 8‐oxo‐7,8‐dihydro‐2'‐deoxyguanosine (8‐oxo‐dG) (pg) per total DNA (µg). A p value of