MMSE Cross-Domain Variability Predicts Cognitive Decline in Centenarians

Abstract

Background: Early detection of dementia is one of the key issues in cognitive gerontology. However, so far the detection of early stages in cognitive decline has been rather unreliable. One central limitation of current assessment strategies is that they rely on information about a person’s level of performance obtained from a single assessment. Objective: In the first part of the present paper, we propose three strategies for overcoming this limitation by using information from several measurement occasions to improve diagnostic reliability. Methods: In the second part, we present one exemplary empirical analysis of one of these approaches reporting data from the Heidelberg Centenarian Study. Results: In this sample of very old individuals tested at baseline and at a follow-up 18 months later, the intra-individual cross-domain variability across MMSE subscales [1]at baseline predicted cognitive decline (i.e. change in an external cognitive functioning rating from baseline to follow-up) much better than baseline mean MMSE scores. Conclusions: In conclusion, we discuss the advantage of performance varibility as a predictor for cognitive decline.

Cross-Domain Variability of Cognitive Performance in Very Old Nursing Home Residents and Community Dwellers: Relationship to Functional Status

“…While caution must be exercised in inferring causality from cross-sectional data, these results provide preliminary evidence that variability across cognitive domains is related to functional disability in very old age. This fi nding is in line with earlier studies showing a longitudinal relationship with crossdomain variability and subsequent cognitive and functional decline [21,22] . However, our results are limited in terms of sampling and test selection procedures.…”

“…Cross-domain variability (task dispersion) was computed using intra-individual standard deviations over z-transformed scores of the eight cognitive variables [17,22] where z i refl ects each participant's z-score of each test i, and m refl ects the mean of each participant's z-scores across all tests. Relatively low values on this score refl ect relatively fl at intra-individual profi les of performance, and relatively high scores refer to uneven performance profi les, indicating high variability within an individual across the cognitive tasks.…”

“…Moreover, evidence has been presented that dropping performance in specifi c subscales of the Mini-Mental State Examination (MMSE) [20] , rather than in the overall sum score, can predict cognitive changes in preclinical Alzheimer's disease [21] . In fact, a recent study examining cross-domain variability as predictor of subsequent decline in centenarians showed cross-domain variability across MMSE subscales to be a better predictor than baseline mean MMSE scores [22] . Furthermore, it has been shown that task dispersion is related to everyday functioning beyond effects of age and education [23] .…”

Does a Reliable Decline in Mini Mental State Examination Total Score Predict Dementia?

“…Patients with AD and mixed dementia were found to decline at significantly faster rates than patients with probable/possible VaD [28] . Other factors might be comorbidity [29] , cross-domain variability [30] , the APOE status [25,31] or physical exercise [32] .…”

Within-Person Variability as a Dynamic Measure of Late-Life Development: New Methodologies and Future Directions

“…Utility of within-person variability as a prognostic indicator of cognitive decline and dementia is demonstrated by Kliegel and Sliwinski [4]. They show that variability across cognitive domains is a better predictor of dementia than MMSE performance at one occasion.…”