Clinical value of the Montreal Cognitive Assessment (MoCA) in patients suspected of cognitive impairment in old age psychiatry. Using the MoCA for triaging to a memory clinic

Figures & data

Figure 1. Flowchart suspected patients. C.I.: Cognitive Impairment; MCI: Mild Cognitive Impairment; No-CI: No Cognitive Impairment; GDS: Global Deterioration Scale; BPSD: Behavioural and Psychological Symptoms of Dementia.

Table 1. Details of the diagnostic tests.

The neuropsychological assessment consisted of the following assessments
Full test	Subtest
Dutch reading test for adults to estimate premorbid intelligence (“Nederlandse Leestest voor Volwassenen” NLV ), proverbs, Zung 12; Self-rating Depression scale (ZDS), Raven Coloured Progressive Matrices Questionnaire for orientation and personal and non-personal episodic memories “Toutenburger Vragenlijst” Visual Association Test (VAT) 15 words imprinting and recall or recognition Copying of Drawings; Meander of Luria, Complex figure of Rey, House, Cube, Greek cross. D-KEFS | Trail Making Test A and B (TMT) Hooper Visual Organization test (VOT-short version) Calculation, spelling and reading Binet- Bobertag story Fluency- test category (and letter) Groninger Intelligence test (GIT) Clock reading and writing	Wechsler Adult intelligence scale; WAIS IV (Symbol substitution, Numerical series/ Digit Span, Agreements/ Similarities, Figures; Figure Weights), Wechsler Memory scale IV; WMS IV (numerical series) Behavioural Assessment of the Dysexecutive Syndrome (BADS; Key search test and Zoo-plan test)
Laboratory tests consisted of:
Full Blood count; Erythrocyte sedimentation rate (ESR); Potassium (K); Sodium (Na); Creatinine (creat); Calcium (Ca); Urea (Ur); Aspartate transaminase (AST); Alanine transaminase (ALT); Gamma-glutamyltransferase (yGT); Alkaline phosphatase (ALP); Glucose non-fasting (Glu); Thyroid Stimulating Hormone (TSH); Albumin; Vitamin B1,B12,D; Folic acid; Albumin (Alb); Total protein; Magnesium (Mg); Syphilis

Table 2. Key demographic and clinical characteristics.

	Dementia (a)	MCI (b)	NoCI (c)	Total referred (d)	Statistic difference p < 0.05
Variable / n	83	153	56	292
Age (SD)	77.3 (7.5)	73.9 (8.0)	71.0 (7.2)	74.3 (8.0)	a>b>c
Range	59–94	53–93	58–85	53–94
Education  < 12 (%)	52	53	44	51	No sig.
Sex F (%)	63	57	56	59	No sig.
GAF (SD)	52 (10.2)	57 (12.8)	54 (11.4)	55 (12.0)	a < b
GDS15 (SD)	6.6 (4.9)	7.7 (4.7)	8.9 (4,3)	8.4 (4.5)	No sig.
MoCA (SD)	16.7 (4.1)	20.9 (3.8)	23.9 (4.3)	20.3 (4.7)	a < b < c
Range	5–26	3–28	12–30	3–30

Education and sex were compared between a,b,c, with a Chi2 test.

Groups a,b,c and were compared with ANOVA.

MCI: Mild Cognitive Impairment; NoCI: No ognitive Impairment; GAF: Global Assessment of Functioning; GDS15: Geriatric Depression Scale 15 question version; MoCA: Montreal Cognitive Assessment.

Figure 2. Boxplot median scores. Upper part Main groups: NoCI: No Cognitive Impairment (n = 83: white boxes). MCI: Mild Cognitive impairment (n = 153: striped boxes). MD: Mild Dementia (n = 56:cross boxes). Lower part DSM IV groups: MD-A: Alzheimer’s Dementia (n = 27). MD-V: Vascular Dementia (n = 15). MD-L: Dementia Lewy-body (n = 9). MD-F: Frontotemporal Dementia (n = 4). MD-M; Dementia mixed causes and Not otherwise specified (n = 28). MCI-ND:MCI due to neurodegenerative process (n = 75). MCI-D: MCI and depression (n = 41). MCI-B: MCI and bipolar disorder (n = 14). MCI-S: MCI and schizophrenia (n = 12). MCI-M: MCI remaining or mixed causes including Not otherwise specified (n = 11). NoCI-D: NoCI and depression (n = 23). NoCI-B: NoCI and Bipolar disorder (n = 9). NoCI-S: NoCI and schizophrenia (n = 7). NoCI-P: NoCI and personality disorders (n = 6). NoCI-M: NoCI and remaining or mixed causes (n = 11). Star outlier  =  3.0 × IQR (Interquartile range). Point outlier  =  1.5 × IQR (Interquartile range).

Figure 3. (a–c). Results of ROC analysis.

Table 3. Area Under the Curve between variations of groups and their sensitivity, specificity, PPV and NPV at cutoff scores 26 and 21 with the best Youden index (n = 292).

Groups						CutOff  < 26				CutOff  < 21
			AUC	SE	Sens	Spec	PPV	NPV	Sens	Spec	PPV	NPV
Dem	vs	NoDem	.830	.026	98	17	31	95	90	65	50	94
Dem	vs	MCI	.810	.029	98	6	36	83	90	63	56	92
CI	vs	NoCI	.770	.040	95	47	88	68	56	73	90	28
MCI	vs	NoCI	.707	.048	94	47	83	72	37	73	79	30

Dem: Dementia; NoDem: No Dementia (MCI + NoCI); MCI: Mild Cognitive impairment; NoCI: Suspected patients no Cognitive Impairment; CI; Cognitive Impairment (Dem + MCI).

AUC: Area Under the Curve; SE: Standard Error; Sens: sensitivity; Spec: specificity; PPV: positive predictive value; NPV: negative predictive value.

Table 4. Sensitivity and Specificity at MoCA scores from 26 to 18.

Cut-off value^a	Sensitivity	Specificity
		MCI + NoCI No Dementia	MCI	NoCI
Dementia
18	54%	86%	83%	93%
19	62%	84%	82%	89%
20	78%	77%	75%	82%
21	90%	65%	63%	73%
22	91%	55%	50%	67%
23	95%	43%	35%	67%
24	98%	34%	24%	64%
25	98%	24%	12%	55%
26	98%	17%	6%	47%
CI (Dem + MCI)
18	30%			93%
19	33%			89%
20	43%			82%
21	56%			73%
22	65%			67%
23	75%			67%
24	84%			64%
25	91%			55%
26	95%			47%
MCI
18	17%			93%
19	18%			89%
20	25%			82%
21	37%			73%
22	50%			67%
23	65%			67%
24	77%			64%
25	88%			55%
26	94%			47%

^a (MoCA-D below score)

Dem: Dementia; MCI: Mild Cognitive impairment; NoCI: Referred patients no Cognitive Impairment; HC: Healthy Controls; CI; Cognitive Impairment (Dem + MCI).