Population norms for the MMSE in the very old - Estimates based on longitudinal data

Objective: To report the percentile distribution of Mini-Mental State Exami nation (MMSE) scores in older people by age, sex, and education level, esti mated from longitudinal data, after correcting for loss due to dropout. Met hods: The Cambridge City over 75 Cohort is a population-based study of a co hort of 2106 subjects age 75 years and older at study entry followed up ove r 9 years. At each of the four waves, cognitive function was assessed using MMSE. Based on these data, the relationship between age and MMSE score was modeled. Percentile distributions by age, sex, and education level were pr ovided using inverse probability weighting to correct for dropouts. Results : Performance on MMSE: was related to age in men and women. In women, at ag e 75, MMSE score ranged from 21 (10th percentile) to 29 (90th percentile). At age 95, the range was 10 (10th percentile) to 27 (90th percentile). The upper end of MMSE distribution was slightly modified with age, whereas the lower end of the distribution was very sensitive to age effect. A similar p attern was observed in both sexes. Conclusion: These findings provide norms for MMSE scores in subjects age 75 years and older from longitudinal popul ation-based data. Such norms can be used as reference values to determine w here an individual's score lies in relation to his or her age, sex, and edu cation level.