Alzheimer ' s disease is the most common cause of senile dementia and memory loss . alzheimer ' s patients may have no problem with long term memory recall , however 阿耳茨海默氏病（早老性痴呆病）是主要的诱发老年痴呆症和记忆力丧失的病因。但是，阿耳茨海默氏病（早老性痴呆病）可能不会影响比较久远的记忆。
Lewy body disease that is quite common in the west , is not commonly encountered . in alzheimer s disease brains in chinese , amyloid deposition predominantes whereas neurofibrillary tangles are less frequently seen 在病种方面，以阿氏痴呆症为主，约占23 ，脑血管性痴呆占13 ；而在西方很常见的路易体痴呆病则非常罕见。
There are around 30 , 000 dementia patients in hong kong . the economic burden of these patients on both the government and individual family is huge , considering each patient needs at least hk $ 6 , 000 a year for drugs to alleviate the ailment 单以治疗痴呆病药物计算，每名病者每年需付出港币六千元以上，老人痴呆症对政府及家庭的经济负担相当不少。
Apoe2 binds poorly to the ldlr , and homozygous inheritance of the apoe2 allele is strongly associated with type iii dyslipoproteinemia . apoe2 and apoe4 are associated with hypercholesterolemia and atherosclerosis ( as ) . the apoe4 is also associated with higher incidence and earlier age of onset of late onset familial alzheimer ' s disease ( ad ) , whereas apoe2 may have the opposite effect Apoe _ 2与ldlr结合能力很差，与型高脂血症关联。 apoe _ 2和apoe _ 4与高胆固醇血症、动脉粥样硬化( as )等疾病有关， apoe _ 4还是老年痴呆( ad )的高发风险因子，而apoe _ 2则对预防老年痴呆病的发生具有积极作用。
