Cerebrospinal Fluid Biomarkers in Alzheimer's Disease and Geriatric Depression: Preliminary Findings from Brazil: CSF Biomarkers in Depression

Aims Depression is a highly prevalent disorder in the elderly and one of the risk factors for developing dementia. The present study involves patients with Alzheimer's disease (AD), geriatric major depressive disorder (MDD) and cognitively healthy controls aiming to compare baseline cerebrospinal fluid (CSF) biomarkers. Methods The study included 52 patients with more than 60 years of age with a diagnosis of MDD, AD, and healthy controls. All individuals underwent a medical history, physical, and neurologic examination, laboratory tests and neuropsychological assessment to rule out any clinical diseases or disorders. Measurement of CSF P-tau181, T-tau, and A beta 42 was performed using commercial assays (ELISA). Results CSF A beta 42 levels of depressed patients and normal controls were significantly higher than in AD. There was not any significant difference in measures of P-tau among the groups. T-tau, however, showed to be significantly different among the groups, with higher measures in AD group. Higher levels of P-tau were observed in four MDD patients compared with controls. Conclusion CSF A beta 42, T-tau, and P-tau levels may differentiate between AD and depression in a Brazilian sample.