Cognitive Function and Amyloid Marker in Frail Older Adults: The COGFRAIL Cohort Study

Background: Frailty and cognitive impairment are common manifestations of the ageing process and are closely related. But the mechanisms linking aging, physical frailty, and cognitive disorders, are complex and remain unclear. Objectives: We aim to explore the role of cerebral amyloid pathology, but also a range of nutritional, physical, biological or brain-aging marker in the development of cognitive frailty. Method: COGFRAIL study is a monocentric prospective study of frail older patients with an objective cognitive impairment (Clinical Dementia Rating Scale global score at 0.5 or 1). Three-hundred-and-twenty-one patients are followed up every 6 months, for 2 years. Clinical assessment at baseline and during follow-up included frailty, physical, mood, sensory, nutritional, and cognitive assessment (with a set of neuropsychological tests). Cerebral amyloid pathology is measured by amyloid Positron Emission Tomography (PET) or amyloid-β-1-42 level in cerebrospinal fluid. Brain magnetic resonance imaging, measurement of body composition using Dual X Ray Absorptiometry and blood sampling are performed. The main outcome of the study is to assess the prevalence of positive cerebral amyloid status according to amyloid PET or amyloid-β-1-42 level CSF. Secondary outcomes included biological, nutritional, MRI imaging, cognitive, clinical, physical and body composition markers to better understand the mechanisms of cognitive frailty. Perspective: COGFRAIL study will give the opportunity to better understand the link between Gerosciences, frailty, cognitive impairment, and Alzheimer’s disease, and to better characterize the physical and cognitive trajectories of frail older adults according to their amyloid status. Understanding the relationship between physical frailty and cognitive impairment is a prerequisite for the development of new interventions that could prevent and treat both conditions.