Reduced frontal perfusion in depressed postmenopausal women: a SPECT study with WCST.

OBJECTIVES

To investigate frontal cerebral blood flow (CBF) in depressed postmenopausal women and its relation to cognitive function and the severity of depressive symptoms.

METHODS

Regional CBF of 20 unmedicated depressed postmenopausal women was measured using Tc-99m HMPAO SPECT, both at rest and during frontal activation using the Wisconsin card sorting test (WCST). Frontal CBF was semi-quantified by comparing the radioactivity in the prefrontal region to the cerebellum (F/C ratio). We measured the severity of the symptoms of depression using the hospital anxiety and depression scale (HADS) and cognitive function using the mini-mental status examination (MMSE).

RESULTS

At rest, there was no difference in frontal CBF between patients with moderate or severe (HADS> or =11) and patients with mild depressive symptoms (HADS<11). During the WCST, however, the HADS> or =11 group did not score as well as the HADS<11 group (P=0.03). The changes in F/C ratios were inversely correlated with HADS scores (r=-0.43, P=0.05) and positively correlated with MMSE scores (r=0.58, P=0.004). After adjusting for age, F/C ratios were significantly correlated with MMSE (P=0.002), but not with HADS scores.

CONCLUSIONS

Frontal CBF did not increase in postmenopausal women with moderate/severe symptoms of depression during the WCST activation task, and reduced frontal CBF was related to the impairment of cognitive function. The combination of the functional activation test and SPECT imaging powerfully revealed this functional disease, which remains undetectable using more common baseline measurements.