CHANGE IN FOLATE STATUS WITH ANTIDEPRESSANT TREATMENT

Ninety-nine consecutive unmedicated outpatients with a major depressiv e illness had blood drawn for measurement of serum folate (SF), red ce ll folate (RCF), and vitamin B-12 within 24 hours of completion of rat ings of severity of depression at the beginning and ending of a 5-week trial of desmethylimipramine (mean dose = 149.2 mg/day, range = 75-22 5 mg). As compared with nonresponders, responders had a significantly higher mean SF at baseline (nonresponders = 13.8 nmol/l; responders = 17.7 nmol/l) and RCF showed a significant inverse correlation with sev erity of depression and a significant positive correlation with age of onset of illness. At week 5, change in severity of depression was sig nificantly correlated with change in RCF, and significantly more respo nders than nonresponders had an increase in RCF. The possible role of folate status in the regulation of mood and response to treatment is d iscussed.