Normative data for middle-aged Brazilians in the Mattis Dementia Rating Scale

Despite the advances in the diagnosis of dementia, neuropsychological assessment remains an important tool. The Mattis Dementia Rating Scale (DRS) was designed to evaluate people with suspected dementia and allows for the analysis of different cognitive domains. Considering the numerous cases of early-onset dementia, specific reference standards aimed at the middle-aged population are necessary.

To provide normative data for the middle-aged Brazilian population in DRS and to investigate the influence of education level, age, sex, and intelligence quotient (IQ) on the results.

Overall, 120 healthcare professionals and caregivers from a hospital, who were healthy, aged between 45 and 64 years, and had at least four years of formal education, were included in the study. They were equally divided into six groups. In each age group (45-54 and 55-64 years), there were three educational levels: 4-7, 8-11, and 12 or more (12+) years of formal education. The results are presented as mean values, standard deviations, and percentiles. Comparisons between groups were carried out for age, sex, and education level. Age, years of formal education, and IQ were also analyzed as continuous variables by Spearman's correlation.

Concerning education level, the comparison between groups showed differences in the results for the total scale and subscales, except for the Construction subscale. No differences were found for age and sex. Correlations observed for years of formal education and IQ were similar. No correlation was found for age.

The present study contributes to the evaluation of dementia concerning people younger than 65 years of age and reinforces the importance of education in the interpretation of the scores.