Age at Onset and Vascular Pathology in Late-Life Depression

Objective: There is considerable evidence to suggest that late-onset depression may be etiologically distinct from early-onset depression. The aim of this study was to compare vascular function and magnetic resonance imaging-defined brain ischemic changes between early-onset depressed (EOD) and late-onset depressed (LOD) subjects. Design: Case-control study. Participants: Twenty-five subjects with late-life depression recruited from secondary care were divided into groups with EOD (<60 years, 11 subjects) and LOD (>60 years, 14 subjects). Measures: All subjects underwent a variety of vascular assessments including pulse wave analysis, pulse wave velocity, carotid intima media thickness (IMT), and magnetic resonance imaging of the brain to assess white matter hyperintensities. Results: The mean age of LOD subjects was 71.3 +/- 4.0 years and EOD was 73.6 +/- 4.7 years (p = NS). There were no baseline differences in vascular risk or sociodemographic variables. LOD subjects had significantly higher common carotid IMT (EOD: 0.06 [0.01]; LOD: 0.09 [0.02], p = 0.02), carotid plaques (EOD: 2.1 [1.1]; LOD: 5.4 [3.9], p = 0.02), and peripheral augmentation index (EOD: 81.7 [7.9]; LOD: 96.2 [21.6], p = 0.04) when compared with early-onset subjects, indicating more vascular pathology. There were no group differences in white matter hyperintensities. Age at onset of depression was positively correlated with peripheral augmentation index, common carotid IMT, and plaque index. Conclusion: This study suggests that elderly subjects with LOD have greater vascular impairment than those with an early-onset illness. Whether preventing vascular disease at an earlier age may decrease the risk of last onset depression is a potential area for future research. (Am J Geriatr Psychiatry 2012; 20:524-532)