Serotonin speeds heart valve damage in some people

Degenerative mitral regurgitation is a common condition in which the valve between two heart chambers fails to close properly. For most people the condition worsens slowly over years. But some patients deteriorate much faster. Why that difference exists was poorly understood.

Antidepressants and a genetic variant

Scientists at Columbia University identified a clue in the combination of a genetic variant and SSRI antidepressant use. SSRIs raise serotonin levels in the blood by blocking its uptake into certain cells. Serotonin can reach the heart valves via platelets circulating in the bloodstream.

According to the researchers, patients who carried a specific variant in the serotonin transporter gene and also used SSRIs were more likely to develop severe valve damage and to require surgery at a younger age. This is an association, not a proven causal relationship.

Serotonin as a tissue aging factor

From a longevity perspective, this finding is notable because it shows how a neurotransmitter operating outside the brain may influence tissue aging. Heart valve walls can become fibrotic, a process in which scar tissue gradually replaces healthy tissue. Serotonin appears to accelerate that fibrotic process in people with a particular genetic background.

The researchers suggest that patients with this genetic variant and existing valve disease should be monitored more closely if they take SSRIs. Adjusting medication is not yet recommended on the basis of this data; clinical trials are needed before that step can be taken.

The findings reflect a broader theme in aging research: chronically elevated levels of signaling molecules can accelerate tissue damage in ways that depend heavily on an individual’s genetic profile.

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Search terms: serotonin heart valve fibrosis, SSRI cardiovascular effects, mitral regurgitation genetic risk