Limitations of the Mini-Mental State Examination for screening dementia in a community with low socioeconomic status: results from the Sao Paulo Ageing & Health Study.
BACKGROUND
The Mini-Mental State Examination (MMSE) is the most widely used instrument for the screening of cognitive impairment worldwide, but its ability to produce valid estimates of dementia in populations of low socioeconomic status and minimal literacy skills has not been adequately established. The authors investigated the psychometric properties of the MMSE in a community-based sample of older Brazilians.


METHODS
Cross-sectional one-phase population-based study of all residents of pre-defined areas of the city of Sao Paulo, aged 65 years or over. The Brazilian version of the MMSE was compared with DSM-IV diagnosis of dementia assessed with a harmonized one-phase procedure developed by the 10/66 Dementia Research Group.


RESULTS
Analyses were performed with 1,933 participants of the SPAH study. Receiver operating characteristic analysis showed that the MMSE cut-point of 14/15 was associated with 78.7% sensitivity and 77.8% specificity for the diagnosis of dementia amongst participants with no formal education, and the cut-point 17/18 with 91.9% sensitivity and 89.5% specificity for those with at least 1 year of formal education (areas under the curves 0.87 and 0.94, respectively; P = 0.03). Even with these best fitting cut-points, the MMSE estimate of the prevalence of dementia was four times higher than determined by the DSM-IV criteria. Education, age, sex and income influenced MMSE scores, independently of dementia caseness.


CONCLUSIONS
The MMSE is an adequate tool for screening dementia in older adults with minimum literacy skills, but misclassification is unacceptably high for older adults who are illiterate, which has serious consequences for research and clinical practice in low and middle income countries, where the proportion of illiteracy among older adults is high.
Department and Institute of Psychiatry, LIM-23, Faculty of Medicine, University of Sao Paulo, R. Dr. Ovidio Pires de Campos 785, Sao Paulo 05403-010, Brazil. scazufca@usp.br
Marcia
M
Scazufca
Osvaldo P
OP
Almeida
Homero P
HP
Vallada
Wernestty A
WA
Tasse
Paulo R
PR
Menezes
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D003430:Cross-Sectional Studies; D003704:Dementia / Q000175:diagnosis* / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000379:methods / Q000706:statistics & numerical data*; D012111:Residence Characteristics; D012680:Sensitivity and Specificity; D012737:Sex Factors; D012959:Socioeconomic Factors