Escitalopram Effects on CSF Amyloid Beta

Alzheimers disease (AD) is a devastating illness, estimated to affect 5 million patients in the United States alone and projected to increase dramatically over the next decades as the population ages unless preventive measures can be developed. The investigators have preliminary evidence that selective serotonin reuptake inhibitor (SSRI) antidepressants lower the amount of amyloid plaques in the human brain. The interventions now propose to study the effects of an SSRI (escitalopram) on levels of amyloid beta peptide (the major constituent of the plaques) in the cerebrospinal fluid (CSF) of cognitively normal older adults.