ARE GENETIC-FACTORS IMPORTANT IN THE ETIOLOGY OF LEUKOARAIOSIS - RESULTS FROM A MEMORY CLINIC POPULATION

Objective. To discover whether polymorphism in either the apolipoprote in E (ApoE) or angiotensin-converting enzyme (ACE) genes is associated with leukoaraiosis, white matter lesions visible on neuroimaging of t he brain, which is commonly seen in dementia as well as some normal el derly subjects. Design, Prospective study of consecutive patients atte nding our memory disorders clinic, to examine the relationship between leukoaraiosis and polymorphism of the ApoE and ACE genes. Setting. Me mory disorders clinic in Bristol, UK. Patients. 182 patients attending the memory disorders clinic for investigation of possible dementia of whom 75% were suffering from dementia, 20% from memory impairment but no dementia and in 5% of whom a dementing illness was thought to be u nlikely; 38% of all patients had visible white matter lesions and 16% had cerebral infarcts. Measures. Patients and/or carers who agreed to participate in the study had their ACE and ApoE genotype determined an d their brain CT/MRI scans were assessed by a neuroradiologist, blind to the result of the genotyping, for the presence or absence of white matter low attenuation. Results, There was a significant association b etween white matter lesions and the DD genotype (p < 0.05), but not th e ApoE genotype. However, this relationship with the DD genotype was o nly significant for patients with a previous infarct. Conclusion, Homo zygosity of ACE gene deletion polymorphism is a risk factor for white matter lesions when it is associated with cerebral infarction, This su ggests that it may be possible to identify subjects who are at greater risk of developing white matter lesions and are at risk of cognitive impairment and possibly dementia. (C) 1998 John Wiley & Sons, Ltd.