Apolipoprotein E4 In Late Onset Depression.

An increased frequency of apolipoprotein E4 has been reported in both late-onset Alzheimer's disease and multi-infarct dementia. It has also been suggested that the Apo E4 allele may increase plasma cholesterol. Late-onset depression (LOD) is frequently associated with cerebrovascular changes as well as cognitive impairment. In this study, Apo E4 phenotyping was performed using isoelectric focussing in 23 patients with LOD and 8 with early onset depression. None had SDAT at time of evaluation. Nine LOD patients and none of EOD patients had E4/3 alleles (p<0.05). Patients with E4/3 had later onset of depression than those with E3 (p<0.05). These preliminary results suggest that the presence of the E4 allele may be linked to LOD and that the pathophysiology in LOD may be related to that in late-onset AD or MID. These findings will be discussed in relation to current knowledge of the role of Apo E alleles in cardiovascular and dementing disorders.