Might SSRIs Reduce the Risk for Alzheimer Disease?

Excessive β-amyloid (Aβ) in the brain has long been associated with Alzheimer disease, and reducing brain Aβ has been investigated as a strategy to reduce disease risk and occurrence. Aβ production is suppressed by serotonin signaling, and selective serotonin reuptake inhibitors (SSRIs) enhance serotonin signaling. To ascertain whether SSRIs might reduce Aβ burden, investigators conducted controlled experiments in humans and in a transgenic mouse model of Alzheimer disease.

In aged, 12-month-old mice, citalopram was associated with dose-dependent reductions in brain interstitial fluid Aβ concentrations; at a citalopram dose comparable to 50 mg/day in humans, the reduction was 24.5%. Compared with vehicle, citalopram administered chronically …