Contribution of white matter hyperintensities, medial temporal lobe atrophy and cortical atrophy on outcome, seven to twelve years after ECT in severely depressed geriatric patients

Abstract

Background: Depression and cognitive decline are highly prevalent and often coexisting, however, the association between depression and dementia remains unclear. White matter hyperintensities (WMH), medial temporal lobe atrophy (MTA) and global cortical atrophy (GCA) are associated with depression, mild cognitive impairment and dementia; these structural abnormalities may therefore represent a common underlying mechanism of these diseases. We conducted a naturalistic prospective follow-up study in patients with severe geriatric depression who were formerly treated with ECT. The aim of the study was to investigate the effects of structural abnormalities in the brain on cognitive decline, dementia and survival.

Method: Survival data of 76 patients was obtained. 39 (51.3%) of them also participated in the follow-up study. Cognitive decline was identified 7-12 years after ECT (median 8.0), using the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A diagnosis of dementia was obtained from the family doctor of the patients.

Results: Forty-two out of the 76 (55.3%) of the patients died during follow-up. Twenty-four out of the remained 39 (65.1%) patients who participated in the follow-up study reported cognitive decline and 7 among the 39 patients (17.9%) were diagnosed with dementia. Depression with psychotic symptoms was significantly associated with absence of cognitive decline at follow-up (p=0.007). WMH was significantly associated with mortality (plog rank=0.048). Finally, we observed a trend in significance between the association of GCA and cognitive decline at follow-up (p=0.078), CONCLUSIONS: Depression with psychotic symptoms is a depression subtype that might not be associated with cognitive decline at follow-up. Moderate or severe WMH before ECT in our cohort of depressed patients was associated with higher mortality and GCA was possibly associated with cognitive decline at follow-up.

Keywords: ECT; Geriatric depression; Global cortical atrophy; White matter hyperintensities.