Forty-five hospitalised patients with DSM-III-R diagnosis of mania, we
re found to have a mean red-cell folate level of 193 nmol/l, as compar
ed to 896 nmol/l in the control group (P < 0.00001). Assessment of ser
um folate in both groups showed no significant difference in the level
s. Furthermore the manic patients and the controls were matched by the
socio-economic status. This indicated that the reduced red-cell folat
e in mania is associated with the illness and not due to reduced absor
ption or dietary deficiency of folate. Considering previous studies th
at showed reduced red-cell folate in depression, our findings suggest
that reduced red-cell folate occurred in both phases of bipolar disord
ers. (C) 1997 Elsevier Science B.V.