Cognitive deficits and polymorphism of apolipoprotein E in Alzheimer's disease

Abstract

The aim of this study was to test the relationship between apolipoprotein E (ApoE) genotypes and patterns of cognitive deficits in Alzheimer's disease (AD). All subjects were diagnosed as probable AD patients on the basis of the DSM-IV and NINCDS-ADRDA criteria. Each subject was examined for (1) ApoE genotype, (2) general level of mental activity (Global Deterioration Scale and Mini-Mental State Examination) and (3) cognitive functions by means of a battery of neuropsychological tests. On the basis of ApoE genotype, patients were subdivided into two groups: the first group consisted of patients with at least one epsilon4 allele (epsilon4+ group), while the second one consisted of patients without the epsilon4 allele (epsilon4- group). Our results showed that several cognitive processes depended on the ApoE genotype. In early stages of AD, patients from the epsilon4+ group had greater deficits in delayed recall of new information. On the other hand, working memory appeared to be more impaired in the epsilon4- group of patients. Independent of the genotype, both groups showed similar impairment of learning ability without, however, deficits in remote memory.