Non-cognitive outcomes in trials of disease-modifying drugs for Alzheimer's disease

Alzheimer's disease (AD) constitutes a major challenge for healthcare systems in countries with ageing populations. The clinical signs include the progressive loss of memory and other cognitive functions. However, AD also has non-cognitive features, such as decline in functional abilities, inducing a spectrum of psychological and behavioural symptoms. There is considerable clinical interest in non-cognitive abnormalities of AD, due to their high prevalence and because non-cognitive features complicate patient management, increasing the burden on caregivers and frequently leading to institutionalisation. Efforts are currently being made to investigate AD pathology and to develop appropriate treatment strategies. These strategies focus on the long-term preservation of cognitive and functional abilities and/or the slowing of disease progression, together with the attenuation of behavioural symptoms and the maintenance of quality of life for the patient and the caregiver. The non-cognitive features of AD are often neglected, but are important outcomes when evaluating the “real-life” benefits of disease-modifying treatments for dementia. We discuss the non-cognitive outcomes of interest, in particular, activities of daily living, nutritional parameters, mood and behavioural features, falls, patient's and caregiver's quality of life and use of health system; and the instruments that can be used to measure them.