The Multilingual Naming Test (MINT) as a Measure of Picture Naming Ability in Alzheimer's Disease

Abstract

Objective: The present study investigated the ability of the Multilingual Naming Test (MINT), a picture naming test recently added to the National Alzheimer's Coordinating Center's (NACC) Uniform Data Set neuropsychological test battery, to detect naming impairment (i.e., dysnomia) across stages of Alzheimer's disease (AD).

Method: Data from the initial administration of the MINT were obtained on NACC participants who were cognitively normal (N = 3,981) or diagnosed with mild cognitive impairment (N = 852) or dementia (N = 1,148) with presumed etiology of AD. Dementia severity was rated using the Clinical Dementia Rating (CDR) scale.

Results: Cross-sectional multiple regression analyses revealed significant effects of diagnostic group, sex, education, age, and race on naming scores. Planned comparisons collapsing across age and education groups revealed significant group differences in naming scores across levels of dementia severity. ROC curve analyses showed good diagnostic accuracy of MINT scores for distinguishing cognitively normal controls from AD dementia, but not from MCI. Within the cognitively normal group, there was a robust interaction between age and education such that naming scores exhibited the most precipitous drop across age groups for the least educated participants. Additionally, education effects were stronger in African-Americans than in Whites (a race-by-education interaction), and race effects were stronger in older than in younger age groups (a race-by-age interaction).

Conclusions: The MINT successfully detects naming deficits at different levels of cognitive impairment in patients with MCI or AD dementia, but comparison to age, sex, race, and education-corrected norms to determine impairment is essential.

Keywords: Alzheimer’s disease; Dysnomia; MCI; MINT; Naming.

Fig. 1.

Graphs depicting the MINT’s ability to detect differences in picture naming ability across level of cognitive impairment plotted separately for (A) age and (B) education. The black line represents the cognitively normal group, with increasing levels of cognitive impairment represented by lighter shading.

Fig. 2.

Scatterplots showing that MINT naming scores were lowest in individuals who are oldest and with the lowest level of education in the cognitively normal elderly. Education level was modeled as a continuous predictor for regression analyses but for visualization purposes was stratified into three levels. Scatter points for 16+ years of education are depicted in black triangles, 13–15 in dark gray squares, and ≤12 years in light gray diamonds.

Fig. 3.

Receiver Operating Characteristic (ROC) curves comparing sensitivity and specificity of MINT scores in discriminating between cognitively normal participants from those with AD (in black) and those with MCI (in dark gray).