Subtle Cognitive Impairment and Alzheimer's Disease-Type Pathological Changes in Cerebrospinal Fluid are Common Among Neurologically Healthy Subjects.

BACKGROUND: The neuropathology of Alzheimer's disease (AD) has previously been shown to be rather common among the elderly. OBJECTIVE: The aim of this study was to inspect the associations between cerebrospinal fluid (CSF) AD biomarker concentrations, age, the APOEɛ4 allele, cardiovascular diseases, diabetes, and cognitive performance in a cohort of a neurologically healthy population. METHODS: This study included 93 subjects (42 men, mean age 67 years) without previous neurological symptoms or subjective cognitive complaints. Their cognition was assessed, and CSF biomarkers and APOEɛ4 status were analyzed. RESULTS: Of the studied subjects, 8.6% (n = 8) had a pathological CSF AD biomarker profile. An increase in age correlated positively with CSF tau pathology and negatively with global cognitive performance. CONCLUSION: AD-type pathological changes in CSF and subtle cognitive impairment are common within a population with no previous memory complaints. Age was the main risk factor for the changes.