A new study suggests that selective serotonin reuptake inhibitors (SSRIs), commonly prescribed antidepressants, may help reduce biological markers of Alzheimer’s disease. Researchers found that long-term SSRI use in patients with AD is associated with reduced tau pathology, a hallmark of the disease, and restored activity in a key brain region.
The study analyzed data from 191 participants in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) comparing individuals with and without SSRI use. Results showed that AD patients who were using SSRIs had significantly lower plasma levels of phosphorylated tau-181, a blood-based marker of tau pathology. Brain scans also revealed that SSRIs restored metabolic activity in the dorsal raphe nucleus (DRN), an early site of tau accumulation and serotonin production.
The DRN is a tiny region deep in the brainstem that is one of the earliest areas to show tau accumulation in AD. It’s also the brain’s primary source of serotonin, the neurotransmitter targeted by SSRIs. In this study, patients on SSRIs showed restored glucose metabolism in the DRN, indicating revived neural function.
However, the impact of SSRIs on cognitive performance was mixed. While some patients performed better on certain cognitive tests, others did not show measurable improvements. The researchers emphasize that this was a cross-sectional study and could not prove cause and effect, nor account for specific types or dosages of SSRI used.
Despite these limitations, the study adds to growing evidence that the brain’s serotonin system is deeply intertwined with Alzheimer’s pathology. SSRIs may offer a surprising ally in the fight against cognitive decline. Further clinical trials are needed to explore the timing, duration, and cognitive impact of SSRI treatment in neurodegenerative diseases.
Source: https://neurosciencenews.com/ssris-alzheimers-brain-29173