Objective: To test that a positive family history and ApoE e4 genotype are prevalent among dementia patients with onset before 70 years of age compared with healthy spousal controls.
Methods: A total of 210 patients with dementia and 82 spousal control participants. Neuropsychiatric examination, Consortium to establish a registry on Alzheimer's disease test battery, Clock-drawing Test, and ApoE genotyping were performed in patients and controls.
Results: Of the 131 patients with Alzheimer dementia, 25 were homozygous for Apo e4. Among dementia patients with a positive family history (n = 83), homozygosity for the Apo e4 genotype was found in 19 (22.9%). A positive family history was highest among Apo e4 homozygous Alzheimer dementia patients (72.0%) and lowest among the cognitively normal spousal controls (9.3%).
Conclusions: In our sample of patients with Alzheimer dementia, approximately 3 of 4 (72.0%) were homozygous for the genotype Apo e4 when they had a positive family history.