Memory impairment on free and cued selective reminding predicts dementia

Objective: To estimate the relative rates of dementia in initially nondemen ted subjects with and without memory impairment defined by baseline free re call from the Free and Cued Selective Reminding (FCSR) test. Background: Ou r approach to identifying persons at high risk for future dementia is to sh ow the presence of memory impairment not caused by other cognitive deficits by using a memory test that controls attention and cognitive processing. W hen the conditions of testing are not adequately controlled, prediction is reduced because age-associated memory deficits due to other cognitive defic its are confused with dementia-associated memory deficits. Methods: Longitu dinal evaluation of 264 initially nondemented, elderly community volunteers from the Einstein Aging Study with clinical and psychometric examinations every 12 to 18 months for up to 10 years. Main Outcome Measures: Dementia w as defined by an algorithmic definition that required a Blessed Information Memory and Concentration score >8 and clinical evidence of functional decl ine. Results: Thirty-two incident cases of dementia developed during follow -up. Survival analyses indicated that subjects with impaired free recall at baseline had dementia develop (relative risk = 75.2, 95% Cl = 9.9 to 567) over 5 years of follow-up at dramatically higher rates than subjects with i ntact free recall after adjusting for age, gender, and education, Conclusio n: Poor performance on free recall from FCSR predicts future dementia. Thes e findings support the existence of a preclinical phase of dementia charact erized by memory impairment, which is present for at least 5 years before d iagnosis.