MICROBLEEDS ARE ASSOCIATED WITH DEPRESSIVE SYMPTOMS IN ALZHEIMER’S DISEASE

Abstract

The co-occurrence of cerebrovascular disease (CVD) and depression led to the ‘vascular depression hypothesis’. In particular white matter hyperintensities (WMH) have been found to be associated with depressive symptoms in population-based studies. We studied whether imaging markers of small vessel disease (SVD) were associated with depressive symptoms in a memory clinic population. We included 2136 patients from the Amsterdam Dementia Cohort: 810 subjective cognitive decline (SCD; 59±9yrs; 43%F; MMSE 28±1), 488 mild cognitive impairment (MCI; 66±7yrs; 36%F; MMSE 26±2) and 838 Alzheimer's disease (AD; 67±7yrs; 51%F; MMSE 20±4). Depressive symptoms were assessed using the 15-item Geriatric Depression Scale (GDS) and scored as absent (GDS<5) or present (GDS≥5). MRI was rated for presence of WMH (Fazekas, 0/1 vs. 2/3), lacunes (absent vs. present) and microbleeds (absent vs. present). We performed logistic regression analyses to investigate associations between WMH, lacunes and microbleeds (independent, in separate models) and depressive symptoms (dependent). All analyses were adjusted for age, gender and education (model 1) and additionally adjusted for MRI field strength, MMSE-score and vascular risk factors (model 2). We stratified for diagnosis. We observed depressive symptoms in 189 (23%) SCD-patients, 123 (25%) MCI-patients, and 143 (17%) AD-patients. Presence of SVD (WMH, lacunes and/or microbleeds) was found in 227 (28%) SCD-patients, 226 (46%) MCI-patients and 342 (40%) AD-patients. AD-patients with microbleeds were more likely to have depressive symptoms compared to AD-patients without microbleeds (odds ratio (OR)=1.75; 95%CI: 1.13–2.71, p<0.05). Microbleeds were not associated with depressive symptoms in SCD or MCI. AD-patients with WMH tended to show less often depressive symptoms compared to AD-patients without WMH (OR=0.64; 95%CI: 0.39–1.06, p=0.08). WMH were not associated with depressive symptoms in SCD and MCI (SCD: OR=1.46; 95%CI: 0.89–2.57;MCI: OR=0.91; 95%CI: 0.55–1.49, both p>0.05). We found no associations between lacunes and depressive symptoms in any group. We found that microbleeds are associated with depressive symptoms in AD. Contrary to our expectations, more severe WMH did not predispose for depressive symptoms in our memory clinic population. These findings suggest that depressive symptoms in AD may be related to underlying cerebral amyloid angiopathy.