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The homocysteine hypothesis of depression

Marshal Folstein1, Timothy Liu, Inga Peter

  • 1FRiedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA. mfolstein@rcn.com

The American Journal of Psychiatry
|June 2, 2007
PubMed

Insights

High homocysteine levels may cause depression by affecting brain blood vessels and neurotransmitters. This suggests checking homocysteine and vitamin levels in older depressed patients.

Area of Science:

  • Neurology
  • Psychiatry
  • Nutritional Science

Background:

  • Elevated homocysteine levels are linked to cerebrovascular disease and depression.
  • A potential mechanism involves homocysteine impacting cerebral vasculature and neurotransmitter function, leading to mood disorders.

Purpose of the Study:

  • To explore the hypothesis that high homocysteine levels contribute to depression via cerebrovascular and neurotransmitter pathways.
  • To propose clinical and research strategies based on the homocysteine depression hypothesis.

Main Methods:

  • Review of existing literature associating homocysteine, cerebrovascular disease, neurotransmitters, and depression.
  • Formulation of a hypothesis linking these factors.
  • Proposal for clinical evaluation and future research designs.

Main Results:

  • High homocysteine is associated with cerebrovascular disease and depression.
  • A plausible pathway suggests homocysteine-induced vascular and neurotransmitter changes cause depression.

Conclusions:

  • The homocysteine depression hypothesis warrants further investigation.
  • Clinical evaluation of older depressed patients should consider homocysteine, folate, B12, and B6 levels, alongside cerebrovascular imaging.

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