Abstract
BACKGROUND: The aim of this study was to examine in elderly men a relationship between depressive symptoms, peripheral vascular disease and cerebral blood flow (CBF). METHODS: Population-based cohort study started with an examination of 809 men at age 55, followed by the first (age 68ys) and second follow up (age 82ys). 128 survivors were examined at age 82 with 99mTc-HMPAO-SPECT to estimate CBF, Zung-Self-Rating-Depression Scale (ZSDS), and Ankle-Brachial Index (ABI). Analysis was performed on men free from stroke and dementia which defined the final study population to 120 subjects. RESULTS: ZSDS in the whole cohort ranged from 0.26 to 0.71 (reference 0.25-1.0). As the frequency of depressive symptoms was low, the case group (n = 31) was defined by ZSDS index above 75th percentile (≥0.48), comprising 9 subjects with mild depression (ZSDS 0.55-0.71) and 22 subjects at 88th percentile and above of the normal range (ZSDS index 0.48-0.54). Cases were more often current smokers at age 68 (44% vs. 24%; p = .02) and had lower systolic blood presure (SBP), lower social and physical activity, and suffered from fatigue, nausea, freezing and leg edema at age 82. Within the case group, ZSDS-index correlated negatively with CBF in subcortical area (r = -.42*), left and right thalamus (r = -.40*, r = -.46**), and right basal nuclei (r = -.35*). ZSDS-index correlated also with ABI at age 82 (right leg r = -.40*; left leg r = -.37*), and with Δ between ABI at age 82 and 68 (right r = -.36*; left r = -.46**). Despite decreasing SBP from age 68 to 82, adjusted multiple regression analysis showed in the case group that higher SBP determined CBF changes in the frontal and parietal areas, independently of ZSDS index, Δ ABI, and smoking. CONCLUSION: In this population-based cohort of octogenarian men free from stroke or dementia, a proportion of subjects with depressive symptoms was low. Still, men with borderline or mild depression scores had lower social and physical activity, persistent smoking habit, worse peripheral circulation in legs, and cerebral perfusion changes in basal nuclei, thalamus and subcortical white matter. Regional CBF decline could be partly mediated by higher SBP.