Vascular risk and depression in outpatients at Groote Schuur Hospital memory clinic

Background and Objective: Depression in the elderly has been linked with stroke, and with white matter lesions, particularly in frontal-subcortical regions responsible for mood regulation. Such evidence of vascular disease has in turn been associated with vascular risk factors such as diabetes, hypertension, smoking, high cholesterol and heart disease. The vascular depression hypothesis (Alexopoulos et al., 1997) proposes that individuals with late-onset depression and vascular risk factors have more apathy, fewer ideational symptoms, and more functional and cognitive impairment. Recent studies offer only limited support for this proposal, perhaps due to lack of comparability of studies, lack of control for factors such as age, medical co-morbidity and functional impairment, and exclusion of patients with cognitive impairment. The current study aimed to test the vascular depression hypothesis in a non-Western sample by examining (a) whether a specific depression symptom profile exists in patients with vascular risk factors, and (b) the relationship between vascular risk, depression and cognitive and functional ability. Method: Retrospective data were gathered from 184 individuals (age>= 55, MMSE >= 17) who had been evaluated at the Groote Schuur Hospital Memory Clinic. Correlational and multiple regression analyses tested relationships between a cumulative vascular risk index, scores on the Cornell Scale for Depression and the Bristol Activities of Daily Living Scale, physical evidence of heart disease and 4 executive function tests (Trail Making Test, category fluency, CLOX I, and an initiation/perseveration index). Results: Vascular risk and depression were significantly related, even after controlling for age and functional impairment. However, using a vascular risk model of vascular depression, the data provided no further support for the vascular depression hypothesis either in terms of (a) a specific depression profile, or (b) the impact of vascular risk and depression on cognitive and functional impairment. There were, however, significant relationships between heart disease and executive function measures, and between all cognitive measures and ADL functioning. Conclusion: The current findings imply there may be a threshold of severity of vascular burden before clinically significant symptoms become apparent. However, the findings may also be explained by a common underlying mechanism (either biological or psychosocial) linking vascular disease and depression. Prospective longitudinal studies are required to clarify causal mechanisms.

Grantor dc:publisher.institution

Department of Psychology

Year dc:date.issued

2009

Author dc:creator

• Kinnear, H

Advisor dc:contributor.advisor

• Thomas, Kevin

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/8972

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/8972