Moreover, several studies have shown that weight loss is associated with an increased risk of the conversion from MCI to dementia,15,41,42 whereas 1 study reported that the significant association only existed among APOE ε4 carriers.43 In this cohort, BMI values among individuals with MCI who later developed dementia were not significantly different from those who were dementia free, and the declines in BMI between these 2 groups were almost parallel with each other. Here, APOE is linked to dementia.