The Prognostic Test Accuracy of the Short and Standard Forms of the Montreal Cognitive Assessment.

INTRODUCTION: Cognitive impairment is a critical concern in stroke care, and international guidelines recommend early cognitive screening. The aim of this study was to determine the prognostic accuracy of both the short and standard forms of the Montreal Cognitive Assessment (MoCA) in predicting long-term cognitive recovery following a stroke. METHODS: For this study, we used data from the Efficacy of Fluoxetine - a Randomized Controlled Trial in Stroke (EFFECTS) study, which encompassed stroke patients from 35 Swedish centers over the period from 2014 to 2019. Cognitive assessments were initially conducted at 2-15 days post-stroke, with follow-up data gathered at 6 months. We used the MoCA for objective cognitive evaluation. For assessing subjective cognitive impairment, we used the memory and thinking domain of the Stroke Impact Scale. For psychometric evaluation of the short Swedish version of MoCA (s-MoCA-SWE), we used cross tables and binary logistic regression. RESULTS: The study included 1,141 patients (62.2% men; median [interquartile range; IQR] age, 72.3 [13.2] years; median [IQR] stroke severity, 3.0 [3.0]). At baseline, the prevalence of cognitive impairment was 71.7% according to the s-MoCA-SWE (≤12) and 67.0% according to the MoCA (≤25). The s-MoCA-SWE demonstrated a sensitivity of 92.3% for correctly identifying patients with objective cognitive impairment and 81.5% for identifying those with subjective impairments at 6 months. Although the s-MoCA-SWE had higher sensitivity, the MoCA had a more balanced sensitivity and specificity in detecting both subjective and objective cognitive impairments. In both crude and multivariable models, the s-MoCA-SWE was more strongly associated than the MoCA with cognitive impairment at 6 months. CONCLUSIONS: Both the short and standard versions of the MoCA appear to be effective in identifying individuals likely to experience persistent cognitive issues following a stroke. Considering the limited time available in an acute stroke unit, the short-form version may be more practical. Nevertheless, further prospective studies are required to validate these findings.

Is the difference real, is the difference relevant: the minimal detectable and clinically important changes in the Montreal Cognitive Assessment.

Background and aims: The Montreal Cognitive Assessment (MoCA) is a widely used instrument for assessing cognitive function in stroke survivors. To interpret changes in MoCA scores accurately, it is crucial to consider the minimal detectable change (MDC) and minimal clinically important difference (MCID). The aim was to establish the MDC and MCID of the MoCA within 6 months after stroke. Methods: This cohort study analysed data from the EFFECTS trial. The MoCA was administered at baseline and at 6-month follow-up. The MDC was calculated as the upper limit of the 95 % confidence interval of the standard error of the MoCA mean. The MCID was determined using anchor-based and distribution methods. The visual analogue recovery scale of the Stroke Impact Scale (SIS [primary anchor]) and Euro Quality of Life-5 Dimensions index (EQ-5D [confirmatory anchor]) were used as anchors. The distribution-based method, the Cohen benchmark effect size was chosen. Results: In total, 1131 (mean age [SD], 71 [10.6] years) participants were included. The mean (SD) MoCA scores at admission and 6-month follow-up were 22 (5.2) and 25 (4.2), respectively. The MDC of the MoCA was 5.1 points. The anchor method yielded the MCIDs 2 and 1.6 points for SIS and EQ-5D, respectively. Using the distribution method, the MCID for the MoCA was 1 point. Conclusions: Even a small change in MoCA scores can be important for stroke survivors; however, larger differences are required to ensure that any difference in MoCA values is a true change and is not related to the inherent variation in the test. Due to small sample sizes, the results of the anchor analysis need to be interpreted with caution.

The impact of stroke on the ability to live an independent life at old age: a community-based cohort study of Swedish men.

INTRODUCTION: Few studies with controls from the same cohort have investigated the impact of stroke on the ability to live an independent life at old age. We aimed to analyze how great an impact being a stroke survivor would have on cognition and disability. We also analyzed the predictive value of baseline cardiovascular risk factors. METHODS: We included 1147 men, free from stroke, dementia, and disability, from the Uppsala Longitudinal Study of Adult Men, between 69-74 years of age. Follow-up data were collected between the ages of 85-89 years and were available for 481 of all 509 survivors. Data on stroke diagnosis were obtained through national registries. Dementia was diagnosed through a systematic review of medical charts and in accordance with the current diagnostic criteria. The primary outcome, preserved functions, was a composite outcome comprising four criteria: no dementia, independent in personal activities of daily living, ability to walk outside unassisted, and not living in an institution. RESULTS: Among 481 survivors with outcome data, 64 (13%) suffered a stroke during the follow-up. Only 31% of stroke cases, compared to 72% of non-stroke cases (adjusted OR 0.20 [95% CI 0.11-0.37]), had preserved functions. The chance of being free of dementia was 60% lower in the stroke group, OR 0.40 [95% CI 0.22-0.72]. No cardiovascular risk factors were independently able to predict preserved functions among stroke cases. CONCLUSION: Stroke has long lasting consequences for many aspects of disability at very high age.