Neurochemical abnormalities in Alzheimer’s disease and Parkinson’s disease — a comparative review

We report a meta-analysis of the brain neurochemical abnormalities in Alzheimer’s (AD) and Parkinson’s disease (PD). Evidence for oxidative stress, and disorders of energy metabolism and excitatory amino acids is presented for both disorders. However, limited data and conflicting findings preclude any definitive statement relating to differences and overlap between the two conditions.