Experience of ApoE study in Thai elderly.

The association between ApoE E 4 and dementia is reported in Alzheimer's disease and other dementia such as in multi-infarct dementia. Objectives : To examine the association between apolipoprotein E genotype (ApoE) and dementia in Thai elderly and patients to examine the alleles frequencies of ApoE in a Thai population. Material and Method : Seventy-eight cases and ninety-four controls from a commu- nity based population were recruited. Their ages were all over 50 years. Dementia was diagnosed by DSM IV criteria. Blood was taken and stored for DNA extraction and for restriction enzyme analysis of ApoE genotype. Descriptive analysis and odds ratios from SPSS 9.0 program were used in this study. Results : Alleles frequencies of ApoE E 2 , E 3 , E 4 in normal controls were 0.03, 0.80, 0.17 and alleles frequencies of ApoE E 3 , E 4 in dementia subjects were 0.71 and 0.29, respectively. Odds ratios for dementia risk of apolipoprotein genes were as follows: 0.62 for A poE E 3 and 1. 98 for A poE E 4 * In this study, forty-two dementia subjects had Alzheimer's disease. Fifty nine point five per cent of Alzheimer's disease subjects carried ApoE E 4 (positive predictive value is 0.60). Conclusion : Thai elderly carry ApoE genotype distribution similar to that reported in other ethnic groups. Bearing ApoE E 4 gene increases the risk of developing dementia. The use of ApoE genotyping can only be a diagnostic adjunct for Alzheimer's disease. Key word : Dementia, ApoE Genotype