Abstract: | Despite much attention to the use of biomarkers for predicting Alzheimer disease, little information is available at the individual level. We used the population‐based Mayo Clinic Study of Aging to estimate absolute risk of cognitive impairment by biomarker group. Risk increased with age and any biomarker abnormality. For example, a 75‐year‐old with abnormal amyloid and cortical thinning biomarkers has about a 20% chance of cognitive impairment by age 80 years, whereas with normal biomarkers the chance is <10%. Persons with only one abnormal biomarker had similar intermediate risks. ANN NEUROL 2019;85:155–160. |