Relationship of deep white matter hyperintensities and apolipoprotein E genotype to depressive symptoms in older adults without clinical depression

Objective: This study examined whether evidence of cerebrovascular disease in the form of magnetic resonance imaging (MRI) signal hyperintensities in white matter was associated with depressive symptoms in a high-functioning group of normal elderly volunteers. Method: Ninety-two community-dwelling elderly individuals participating in a study of white matter hyperintensities (WMHs) in normal aging whose apoli poprotein E (APOE) genotype had been determined completed the Geriatric Dep ression Scale and received an MRI scan. Univariate analyses of variance wer e used to examine the relationship between depressive symptoms and the loca tion of WMHs (in deep white matter versus in periventricular white matter) and to determine whether WMHs were more likely to be associated with sympto ms of impaired motivation and concentration or with mood symptoms. The effe ct on depressive symptoms of the interaction between severity of cerebrovas cular disease as evidenced by WMHs and APOE genotype was also examined. Results: Hyperintensities in the deep white matter, but not in the perivent ricular white matter, were associated with depressive symptoms, especially symptoms of impaired motivation, concentration, and decision making. The re lationship between deep WMHs and depressive symptoms was especially strong in individuals carrying the APOE-4 allele. Conclusions: The pattern of depressive symptoms associated with WMHs in thi s study was similar to the pattern described in the literature as character izing "vascular" depression in older persons with major depression. The res ults suggest that cerebrovascular disease may also underlie the depressive symptoms often found in older individuals who are not clinically depressed.