Predictive value of folate, vitamin B12 and homocysteine levels in late-life depression.
BACKGROUND
The role of folate, vitamin B(12) and homocysteine levels in depression is not clear.


AIMS
To investigate cross-sectional and prospective associations between folate, B(12) and homocysteine levels and late-life depression.


METHOD
A total of 732 Korean people aged 65 years or over were evaluated at baseline. Of the 631 persons who were not depressed, 521 (83%) were followed over a period of 2-3 years and incident depression was ascertained with the Geriatric Mental State schedule. Serum folate, serum vitamin B(12) and plasma homocysteine levels were assayed at both baseline and follow-up.


RESULTS
Lower levels of folate and vitamin B(12) and higher homocysteine levels at baseline were associated with a higher risk of incident depression at follow-up. Incident depression was associated with a decline in vitamin B(12) and an increase in homocysteine levels over the follow-up period.


CONCLUSIONS
Lower folate, lower vitamin B(12) and raised homocysteine levels may be risk factors for late-life depression.