L. Han et al., Tracking cognitive decline in Alzheimer's disease using the mini-mental state examination: A meta-analysis, INT PSYCHOG, 12(2), 2000, pp. 231-247
Citations number
54
Categorie Soggetti
Public Health & Health Care Science","Clinical Psycology & Psychiatry
To estimate the annual rate of change scores (ARC) on the Mini-Mental State
Examination (MMSE) in Alzheimer's disease (AD) and to identify study or po
pulation characteristics that may affect the ARC estimation. Methods: MEDLI
NE was searched for articles published from January 1981 to November 1997 u
sing the following keywords: AD and longitudinal study or prognosis or cogn
itive decline. The bibliographies of review articles and relevant papers we
re searched for additional references. All retrieved articles were screened
to meet the following inclusion criteria: (a) original study; (b) addresse
d cognitive decline or prognosis or course of AD; (c) published in English;
(d) study population included AD patients with ascertainable sample size;
(e) used either clinical or pathological diagnostic criteria; (f) longitudi
nal study design; and (g) used the MMSE as one of the outcome measures. Dat
a were systematically abstracted from the included studies, and a random ef
fects regression model was employed to synthesize relevant data across stud
ies and to evaluate the effects of study methodology on ARC estimation and
its effect size. Results: Of the 439 studies screened, 43 met all the inclu
sion criteria. After 6 studies with inadequate or overlapping data were exc
luded, 37 studies involving 3,492 AD patients followed over an average of 2
years were included in the meta-analysis. The pooled estimate of ARC was 3
.3 (95% confidence interval [CI]: 2.9-3.7). The observed variability in ARC
across studies could not be explained with the covariates we studied, wher
eas part of the variability in the effect size of ARC could be explained by
the minimum MMSE score at en try and number of assessments. Conclusions: A
pooled average estimate of ARC in AD patients was 3.3 points (95% CI: 2.9-
3.7) on the MMSE. Significant heterogeneity of ARC estimates existed across
the studies and cannot be explained by the study or population characteris
tics investigated. Effect size of ARC was related to the initial. MMSE scor
e of the study population and the number of assessments.