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Journal of Alzheimer’s Disease 43 (2015) 19–22 DOI 10.3233/JAD-140774 IOS Press
Short Communication
The Montreal Cognitive Assessment in Cognitively-Intact Elderly: A Case for Age-adjusted Cutoffs Noga Orena,b,c,d,1 , Galit Yogev-Seligmanna,b,1 , Elissa Ashc,d , Talma Hendlera,b,e,f , Nir Giladia,c,d and Yulia Lernera,b,d,∗ a Faculty
of Medicine, Tel-Aviv University, Tel Aviv, Israel
b Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel c Center
for Memory and Attention Disorders, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel of Neurology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel e Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel f School of Psychological Sciences, Tel-Aviv University, Tel Aviv, Israel d Department
Handling Associate Editor: Amos Korczyn
Accepted 26 May 2014
Abstract. The Montreal Cognitive Assessment (MoCA) is a widely used screening test for evaluation of mild cognitive impairment (MCI), with a single cutoff for all ages. We examined whether it is associated with age in a sample of cognitively-intact elderly (CIE). The average MoCA score was negatively correlated with age and was significantly higher for younger than older CIE. Additionally, 42% of the older elderly fell below the proposed MCI cutoff score, although all subjects were CIE. Thus, cognitive abilities captured by the MoCA test decrease with age, even in CIE. Therefore, cutoff scores by age for the MoCA are needed. Keywords: Aging, cognition, MOCA, screening, MCI
INTRODUCTION The Montreal Cognitive Assessment (MoCA) [1] is a cognitive screening tool, widely used in both clinical and experimental settings and with variety of disorders [e.g., 2]. The commonly used screening cutoff score for mild cognitive impairment (MCI) is 26 [1], 1 These
authors contributed equally to this work. to: Dr. Yulia Lerner, Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel. Tel.: +972 3 6973953; Fax: +972 3 6973080; E-mail: [email protected]. ∗ Correspondence
though there is an ongoing debate on this issue [3, 4]. Since the mean MoCA score in large samples of elderly individuals decreased with age [3, 5], it is debatable whether a single cutoff for all ages, as is the practice today [1], is appropriate. Yet the subjects in those large studies [3, 5] were not screened for cognitive status to exclude individuals with cognitive decline [4]. Therefore, it remains unclear whether age is associated with the MoCA scores in a sample of cognitively-intact elderly (CIE) carefully selected following evaluation for cognitive functions. Here, we explored the relation between MoCA scores and age in CIE.
ISSN 1387-2877/15/$27.50 © 2015 – IOS Press and the authors. All rights reserved
20
N. Oren et al. / MoCA Assessment in Cognitively-Intact Elderly
METHODS Participants Fifty-four seniors (34 females, age 60–82) participated in the study. Participants were recruited by ads posted at local community and sport centers and from acquaintances of the experimenters and other participants. After neuropsychological assessment, 11 individuals (5 females) were excluded from the study due to impaired cognitive functions (see below criteria for exclusion). Inclusion criteria: 1) age of 60 years old or above; 2) autonomy in daily living activities; 3) fluent Hebrew; 4) no subjective complains about changes in cognition; 5) no history of neurological disorders or clinically significant psychiatric problems. The experimental procedure was approved by the Ethics Committee at the Tel-Aviv Sourasky Medical Center and all participants provided written informed consent. Procedures Neuropsychological assessment All participants completed a comprehensive neuropsychological assessment, with Hebrew version of the following tests: MoCA [1, 6], Rey Auditory Verbal Learning Test (RAVLT) [7] (trials 1–8 only), verbal fluency [8], Rey-Osterrieth complex figure (ROCF) test [9], logical memory test from the Wechsler Memory Scale (WMS), and digit span test from the Wechsler Adult Intelligence Scale (WAIS). An age-specific standard score was calculated in each of the tests, apart from the MoCA, which does not have such norms. Exclusion process Based on the neuropsychological assessment, participants were excluded from further analysis if at least one of the cognitive tests had a score 1.5 standard deviations (SD) below the normative age average. In the RAVLT, specifically, the exclusion criterion was at least 2 out of 8 trials that had a score 1.5 SD below the normative age average. Importantly, the MoCA score was not used as an exclusion criterion.
mean: 17.63 SD: 3.02); and 2) ‘old elderly’ (n = 21; ages range: 70–82, mean: 75.81, SD: 2.73 education mean: 16.53, SD: 2.61). The differences between the subgroups in the MoCA total score, the MoCA separate domains, and the other neuropsychological tests used in the assessment (see ‘Procedures’) were examined, using independent-samples t-tests. The MoCA’s [1] separate domains are: short-term memory recall, visuospatial, executive functions, attention, language, and orientation. The percentage of the participants in each subgroup that were below the proposed MCI cutoff score (i.e., had a score of 25 or lower) was calculated. RESULTS The mean MoCA score across all CIE was 26.65 (SD: 1.6), above the MCI cutoff [1]. However, significant negative correlation between the MoCA score and age was observed (r(43) = −0.342, p = 0.025), indicating that among CIE the MoCA score decreases as age rises. To further explore this age-related specificity, participants were stratified by age into two subgroups: ‘young elderly’ and ‘old elderly’. The subgroups differed significantly by age (t(41) = −12.66, p < 0.001), but not by education (t(41) = 1.2, p = 0.26). The MoCA score of ‘young elderly’ (mean: 27.32, SD: 1.29) was higher than the score of ‘old elderly’ (mean: 25.95, SD: 1.63), and this difference was significant (t(41) = 3.06, p = 0.004). Although the mean MoCA score of the ‘old elderly’ subgroup was not far below the proposed MCI cutoff score, 42% of them were below it (9 out of 21 participants had MoCA scores of 25 or lower). In contrast, only 0.09% of the ‘young elderly’ were below that cutoff (2 of 22 participants had MoCA score of 25). Further, we analyzed performance by the subgroups in the MoCA’s separate domains. Results revealed significant differences between the subgroups in the short-term memory recall only (t(41) = 2.5, p = 0.016; Table 1). Finally, the differences between the subgroups in any of the other neuropsychological tests administrated in the cognitive assessment were not significant (Table 2), as they had age-specific standard scores.
Data analysis
DISCUSSION
First, for all CIE, correlation between the MoCA score and age was examined, using Pearson’s correlation coefficient. Next, participants were stratified by age into two subgroups: 1) ‘young elderly’ (n = 22; ages range: 60–69 mean: 65.05, SD: 2.83, education
The current study with a sample of CIE demonstrated the necessity for cutoffs by age for the MoCA test [1]. Our results confirmed that the MoCA score decreases as age rises in a sample of CIE, suggesting that a single cutoff regardless of age may cause an over-
N. Oren et al. / MoCA Assessment in Cognitively-Intact Elderly
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Table 1 Mean scores of the ‘young elderly’ and ‘old elderly’ subgroups in the MoCA [1] and its’ separate domains MoCA MoCA
Journal of Alzheimer’s Disease 43 (2015) 19–22 DOI 10.3233/JAD-140774 IOS Press
Short Communication
The Montreal Cognitive Assessment in Cognitively-Intact Elderly: A Case for Age-adjusted Cutoffs Noga Orena,b,c,d,1 , Galit Yogev-Seligmanna,b,1 , Elissa Ashc,d , Talma Hendlera,b,e,f , Nir Giladia,c,d and Yulia Lernera,b,d,∗ a Faculty
of Medicine, Tel-Aviv University, Tel Aviv, Israel
b Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel c Center
for Memory and Attention Disorders, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel of Neurology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel e Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel f School of Psychological Sciences, Tel-Aviv University, Tel Aviv, Israel d Department
Handling Associate Editor: Amos Korczyn
Accepted 26 May 2014
Abstract. The Montreal Cognitive Assessment (MoCA) is a widely used screening test for evaluation of mild cognitive impairment (MCI), with a single cutoff for all ages. We examined whether it is associated with age in a sample of cognitively-intact elderly (CIE). The average MoCA score was negatively correlated with age and was significantly higher for younger than older CIE. Additionally, 42% of the older elderly fell below the proposed MCI cutoff score, although all subjects were CIE. Thus, cognitive abilities captured by the MoCA test decrease with age, even in CIE. Therefore, cutoff scores by age for the MoCA are needed. Keywords: Aging, cognition, MOCA, screening, MCI
INTRODUCTION The Montreal Cognitive Assessment (MoCA) [1] is a cognitive screening tool, widely used in both clinical and experimental settings and with variety of disorders [e.g., 2]. The commonly used screening cutoff score for mild cognitive impairment (MCI) is 26 [1], 1 These
authors contributed equally to this work. to: Dr. Yulia Lerner, Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel. Tel.: +972 3 6973953; Fax: +972 3 6973080; E-mail: [email protected]. ∗ Correspondence
though there is an ongoing debate on this issue [3, 4]. Since the mean MoCA score in large samples of elderly individuals decreased with age [3, 5], it is debatable whether a single cutoff for all ages, as is the practice today [1], is appropriate. Yet the subjects in those large studies [3, 5] were not screened for cognitive status to exclude individuals with cognitive decline [4]. Therefore, it remains unclear whether age is associated with the MoCA scores in a sample of cognitively-intact elderly (CIE) carefully selected following evaluation for cognitive functions. Here, we explored the relation between MoCA scores and age in CIE.
ISSN 1387-2877/15/$27.50 © 2015 – IOS Press and the authors. All rights reserved
20
N. Oren et al. / MoCA Assessment in Cognitively-Intact Elderly
METHODS Participants Fifty-four seniors (34 females, age 60–82) participated in the study. Participants were recruited by ads posted at local community and sport centers and from acquaintances of the experimenters and other participants. After neuropsychological assessment, 11 individuals (5 females) were excluded from the study due to impaired cognitive functions (see below criteria for exclusion). Inclusion criteria: 1) age of 60 years old or above; 2) autonomy in daily living activities; 3) fluent Hebrew; 4) no subjective complains about changes in cognition; 5) no history of neurological disorders or clinically significant psychiatric problems. The experimental procedure was approved by the Ethics Committee at the Tel-Aviv Sourasky Medical Center and all participants provided written informed consent. Procedures Neuropsychological assessment All participants completed a comprehensive neuropsychological assessment, with Hebrew version of the following tests: MoCA [1, 6], Rey Auditory Verbal Learning Test (RAVLT) [7] (trials 1–8 only), verbal fluency [8], Rey-Osterrieth complex figure (ROCF) test [9], logical memory test from the Wechsler Memory Scale (WMS), and digit span test from the Wechsler Adult Intelligence Scale (WAIS). An age-specific standard score was calculated in each of the tests, apart from the MoCA, which does not have such norms. Exclusion process Based on the neuropsychological assessment, participants were excluded from further analysis if at least one of the cognitive tests had a score 1.5 standard deviations (SD) below the normative age average. In the RAVLT, specifically, the exclusion criterion was at least 2 out of 8 trials that had a score 1.5 SD below the normative age average. Importantly, the MoCA score was not used as an exclusion criterion.
mean: 17.63 SD: 3.02); and 2) ‘old elderly’ (n = 21; ages range: 70–82, mean: 75.81, SD: 2.73 education mean: 16.53, SD: 2.61). The differences between the subgroups in the MoCA total score, the MoCA separate domains, and the other neuropsychological tests used in the assessment (see ‘Procedures’) were examined, using independent-samples t-tests. The MoCA’s [1] separate domains are: short-term memory recall, visuospatial, executive functions, attention, language, and orientation. The percentage of the participants in each subgroup that were below the proposed MCI cutoff score (i.e., had a score of 25 or lower) was calculated. RESULTS The mean MoCA score across all CIE was 26.65 (SD: 1.6), above the MCI cutoff [1]. However, significant negative correlation between the MoCA score and age was observed (r(43) = −0.342, p = 0.025), indicating that among CIE the MoCA score decreases as age rises. To further explore this age-related specificity, participants were stratified by age into two subgroups: ‘young elderly’ and ‘old elderly’. The subgroups differed significantly by age (t(41) = −12.66, p < 0.001), but not by education (t(41) = 1.2, p = 0.26). The MoCA score of ‘young elderly’ (mean: 27.32, SD: 1.29) was higher than the score of ‘old elderly’ (mean: 25.95, SD: 1.63), and this difference was significant (t(41) = 3.06, p = 0.004). Although the mean MoCA score of the ‘old elderly’ subgroup was not far below the proposed MCI cutoff score, 42% of them were below it (9 out of 21 participants had MoCA scores of 25 or lower). In contrast, only 0.09% of the ‘young elderly’ were below that cutoff (2 of 22 participants had MoCA score of 25). Further, we analyzed performance by the subgroups in the MoCA’s separate domains. Results revealed significant differences between the subgroups in the short-term memory recall only (t(41) = 2.5, p = 0.016; Table 1). Finally, the differences between the subgroups in any of the other neuropsychological tests administrated in the cognitive assessment were not significant (Table 2), as they had age-specific standard scores.
Data analysis
DISCUSSION
First, for all CIE, correlation between the MoCA score and age was examined, using Pearson’s correlation coefficient. Next, participants were stratified by age into two subgroups: 1) ‘young elderly’ (n = 22; ages range: 60–69 mean: 65.05, SD: 2.83, education
The current study with a sample of CIE demonstrated the necessity for cutoffs by age for the MoCA test [1]. Our results confirmed that the MoCA score decreases as age rises in a sample of CIE, suggesting that a single cutoff regardless of age may cause an over-
N. Oren et al. / MoCA Assessment in Cognitively-Intact Elderly
21
Table 1 Mean scores of the ‘young elderly’ and ‘old elderly’ subgroups in the MoCA [1] and its’ separate domains MoCA MoCA
