Trajectories of Mini-Mental State Examination Scores over the Lifespan in General Populations: A Systematic Review and Meta-Regression Analysis

Objectives: Over the lifespan cumulative changes to the brain lead to cognitive decline and eventually to dementia in 20–25% of adults 85 years and older. A commonly used screening tool for cognitive function is the Standard 30 point Mini-Mental State Examination (MMSE). Though the MMSE is used to screen for dementia, little is known about the changes in scores over the lifespan in general populations. Method: A systematic search was conducted using Cochrane, EMBASE, MEDLINE and PsycINFO for articles published from January 1, 2007 to May 25, 2017. Articles were included if they had a longitudinal design reporting at least two MMSE scores. A mixed-effect meta-regression analysis was conducted to examine the influence of age on MMSE score followed by a change-point regression analysis determining the age at which MMSE declines. Results: 45 articles including 58,939 individuals (age range 18–108 years, 61.2% female) summarized 222 MMSE point estimates from 35 cohorts. The meta-regression demonstrated a significant decrease in MMSE scores with higher age (regression coefficient of age: −0.10 (Confidence Interval (CI) −0.15, −0.05)). The average annual decline in MMSE scores identified by the change-point analysis at the age of 41 years and 84 years were −0.04 (95% CI: −0.05, −0.03) and −0.53 (95% CI: −0.55, −0.50), respectively. Conclusions: Between the age of 29 and 105 years MMSE scores decline, with the highest decline between age 84 and 105 years. Clinical Implementations: The use of MMSE should be restricted to higher age categories in aging general populations.