Relationship between executive dysfunction and neuropsychiatric symptoms and impaired instrumental activities of daily living among patients with very mild Alzheimer's disease.

Objectives: Patients with Alzheimer's disease (AD) experience a gradual loss in their ability to perform instrumental activities of daily living (IADLs) from the early stage. A better understanding of the possible factors associated with IADL decline is important for the development of effective rehabilitation and support programs for patients with AD. Thus, we examined the relationships between comprehensive cognitive functions and neuropsychiatric symptoms and IADLs in patients with very mild AD.