Gender differences in the cognitive impairment in Alzheimer's disease

Introduction: There is evidence for gender differences in cognitive functioning. Men and women with Alzheimer's disease (AD) might also differ in the pattern of cognitive deficits. We hypothesised that gender differences in the cognitive deficits of Alzheimer's disease may be related to pre-existing gender differences in cognitive functioning. Method: The performances of 84 subjects with AD and 438 non-demented elderly, using the structured interview for the diagnosis of dementia of the Alzheimer type, multi-infarct dementia and dementias of other aetiology according to ICD-10 and DSM-III-R (SIDAM), were investigated. Subscores for different cognitive functions were compared between men and women. Confounding variables, i.e. age, degree of cognitive impairment, level of education, presence of lifetime diagnosis of major depression and of recent depressive symptoms, were accounted for by multiple regression analyses. Results: Non-demented elderly women had inferior visuoconstructive skills than men. In agreement, women with Alzheimer's disease also had inferior visuoconstructive skills, but in addition they tended to perform worse in items for intellectual abilities than men. Conclusion: Women seem to have minor weaknesses in spatial thinking compared to men. This may explain the inferior test results of non-demented and demented women in visuoconstructive tasks. However, our data also give some evidence for additional domain specific gender differences of cognitive impairment of AD that could not be observed in non-demented elderly, i.e. inferior test results in items for intellectual abilities in demented women compared with demented men. Gender differences in the neurodegenerative process of AD may add to gender differences in domain specific cognitive impairment. Further research on this topic is needed.