CRITICALLY APPRAISED PAPER (CAP) Godefroy, O., Fickl, A., Roussel, M., Auribault, C., Bugnicourt, J. M., Lamy, C., Petitnicolas, G. (2011). Is the Montreal cognitive assessment superior to the mini-mental state examination to detect poststroke cognitive impairment? A study with neuropsychological evaluation. Stroke: A Journal of Cerebral Circulation, 42(6), 1712 1716. http://dx.doi.org/10.1161/strokeaha.110.606277 CLINICAL BOTTOM LINE: Briefly discuss how the evidence relates to occupational therapy practice (i.e., within the scope of traditional or emerging practice) AND how can practitioners use the evidence relative to the target population and practice setting. Cognitive assessments are traditionally completed in the sub-acute phase after stroke. During the acute phase of stroke, complex cognitive evaluations are typically inappropriate due to time constraints and the general health of the patient. Many adults leave the hospital with undetected cognitive impairments, which may limit their independence in participating in meaningful occupations. It is important for occupational therapists to screen cognitive functioning of adults in the acute phase after acute stroke to better understand the activity limitations. This will give therapists the tools they need to make safe discharge recommendations and advocate for appropriate occupational therapy follow up. Research is needed to determine which cognitive screening is superior in detecting cognitive impairments within the acute stroke population. This article explores whether the Mini-Mental Status Examination (MMSE) and Montreal Cognitive Assessment (MoCA) are able to accurately detect cognitive impairments during the acute phase of stroke. Patients were assessed with both the MMSE and MoCA during the acute phase of stroke, followed by a complex neuropsychological battery during the subacute phase of stroke. This study provides occupational therapists with evidence that the MMSE and MoCA are both sensitive enough to detect cognitive impairments in an acute stroke population. RESEARCH OBJECTIVE(S) List study objectives. Assess the determinate validity of the MoCA and MMSE to detect poststroke cognitive impairment (p. 1712) Determine clinical value of the MMSE and MoCA compared to the gold standard neuropsychological battery 1
Assess the value of the of MMSE and MoCA in detecting acute post stroke cognitive impairment DESIGN TYPE AND LEVEL OF EVIDENCE: Level III: Single group, non-randomized, test retest study design SAMPLE SELECTION How were subjects recruited and selected to participate? Please describe. Convenience sample recruited from the Acute Stroke Unit of Soissons Hospital and Amiens University Hospital. Inclusion Criteria Participants were admitted for stroke, including cerebral infarct or hemorrhagic stroke between November 2008 and March 2009. Exclusion Criteria National Institutes of Health Stroke Scale (NIHSS) 1a > 1, NIHSS 1b >1, NIHSS 9 > 2, illiteracy, mental retardation, primary language other than French, schizophrenia and psychosis, previous severe traumatic brain injury, and absence of informed consent SAMPLE CHARACTERISTICS N= (Number of participants taking part in the study) 95 #/ (%) Male 60/ 63% #/ (%) Female 35/ 37% Ethnicity Ethnicity of participants not indicated Disease/disability diagnosis Cerebral infarct: n = 88; hemorrhagic stroke: n = 7 Of the 88 cerebral infarcts: MCA (middle cerebral artery) stroke: n = 65, PCA stroke: n = 4, ACA (anterior cerebral artery) stroke: n = 1, posterior fossa stroke 18. Causes of cerebral infarct: atherosclerosis: n = 18, cardioembolism: n = 18, small vessel disease: n = 11, cervical artery dissection: n = 5, multiple or undetermined causes: n = 36. Of the 7 hemorrhagic strokes: lobar: n = 3, deep: n = 4. 2
Stroke side: left: n = 39, right: n = 44, bilateral: n = 12 INTERVENTION(S) AND CONTROL GROUPS Add groups if necessary No interventions were utilized in this study. MEASURES AND OUTCOMES Complete for each measure relevant to occupational therapy: Measure 1: Name/type of measure used: What outcome was measured? reliable? valid? When is the measure used? MoCA, 10-minute cognitive screening The following cognitive components were measured: attention and concentration, executive functions, memory, language, visuoconstructional skills, conceptual thinking, calculations, and orientation. YES NR YES NR 6.6 ±3.5 days after onset of stroke Measurement 2: Name/type of measure used: What outcome was measured? reliable? valid? When is the measure used? Measure 3: Name/type of measure used: MMSE, 5 10-minute cognitive screening The following cognitive components were measured: registration, attention, calculation, recall, language, ability to follow simple commands, and orientation. YES NR YES NR 6.6 ± 3.5 days after onset of stroke Comprehensive neuropsychological battery that assessed depression, anxiety, and general intellectual efficiency (Mattis Dementia Rating Scale) as well as 5 cognitive domains: 1. Language (Shortened Token test) and confrontation naming 2. Visuoconstructive abilities (Alberta cancellation test) and copy of complex figure 3. Working and long-term memory (French adaptation of the Grober and Buschke procedure) 3
What outcome was measured? reliable? valid? When is the measure used? 4. Action speed using the digit symbol substitution subtest time to complete the part A of the Trail Making test, and time to complete the naming test of the Stroop test 5. Executive functions using a French adaptation of the Trail Making test, categorical (animals) and literal (letter P ) verbal fluencies, and Stroop test. The following cognitive components were measured: depression, anxiety, general intellectual efficiency, and 5 cognitive domains: language, visuoconstructive abilities, working (forward and backward digit span) and long-term memory, action speed, and executive functioning NR NR 24.1 + 6.4 days after onset of stroke Measurement Biases Were the evaluators blind to treatment status? Check yes, no, or NR, and if no, explain. NR Comment: There were no treatments involved in the study and therefore measurement bias was not reported. Recall or memory bias. Check yes, no, or NR, and if yes, explain. NR Comment: RESULTS List key findings based on study objectives Include statistical significance where appropriate (p < 0.05) Include effect size if reported The MMSE was impaired less frequently than the MoCA (p = 0.0001). All patients who had an impaired score on the MMSE also had an impaired MoCA score. When raw scores were analyzed, the MMSE demonstrated moderate sensitivity (sensitivity, 0.66) to cognitive impairment and good specificity (specificity, 0.97). The MoCA demonstrated good sensitivity (sensitivity 0.94) and moderate specificity (specificity, 0.42). When adjusted scores were used (refined scores that controlled for the effect of confounding factors such as age and education), the sensitivity and specificity of the MMSE and MoCA were similar (MMSE sensitivity = 0.7, MMSE specificity = 0.97; MoCA sensitivity = 0.67, MoCA specificity = 0.9) Cognitive impairment detected on MMSE was the strongest predictor of cognitive impairment on neuropschological battery (p = 0.0001). The subjects 4
with pre-stroke dementia were excluded and statistics were run again. The statistics were the same with 80 subjects and the exclusion of the pre-stroke dementia group. Both the MMSE and the MoCA have good ability to discriminate between impaired and nonimpaired cognitive status. Was this study adequately powered (large enough to show a difference)? Check yes, no, or NR, and if no, explain. NR Comment: Were appropriate analytic methods used? Check yes, no, or NR, and if no, explain. YES Comment: NR Were statistics appropriately reported (in written or table format)? Check yes or no, and if no, explain. YES Comment: Was the percent/number of subjects/participants who dropped out of the study reported? NO Limitations: What are the overall study limitations? The sample size did provide statistically significant results, but the number of subjects is relatively small. Also, the researchers did not exclude subjects who have associated neurological deficits, including dementia. The researchers did run statistics with those individuals excluded from the study. There was no difference in the statistical findings with the neurological deficit group excluded. CONCLUSIONS State the authors conclusions related to the research objectives. Findings suggest that cognitive screenings such as the MMSE and MoCA are able to accurately detect cognitive impairments in individuals with acute stroke at a level commensurate with longer and more comprehensive neuropsychological evaluations. To accurately diagnose cognitive impairment in those with MMSE scores 29 and MoCA scores 26, a comprehensive neuropsychological battery would be indicated to prevent false negative results. 5
This work is based on the evidence-based literature review completed by Michelle Voyer, MS, OTR/L, and Stacey Reynolds, PhD, OTR/L, Faculty Advisor, Virginia Commonwealth University. CAP Worksheet adapted from Critical Review Form--Quantitative Studies. Copyright 1998, by M. Law, D. Stewart, N. Pollack, L. Letts, J. Bosch, & M. Westmorland, McMaster University. Used with permission. For personal or educational use only. All other uses require permission from AOTA. Contact: www.copyright.com 6