Screening for Cognitive Impairment After Stroke: Validation of the Chinese Version of the Quick Mild Cognitive Impairment Screen

Abstract

Background: Screening for post-stroke cognitive impairment (PSCI) is necessary because stroke increases the incidence of and accelerates premorbid cognitive decline. The Quick Mild Cognitive Impairment (Qmci) screen is a short, reliable and accurate cognitive screening instrument but is not yet validated in PSCI. We compared the diagnostic accuracy of a Chinese version of the Qmci screen (Qmci-CN) compared with the widely-used Chinese versions of the Montreal Cognitive Assessment (MoCA-CN) and Mini-Mental State Examination (MMSE-CN).Methods: We recruited 34 patients who had recovered from a stroke in rehabilitation unit clinics in 2 university hospitals in China: 11 with post-stroke dementia (PSD), 15 with post-stroke cognitive impairment no dementia (PSCIND), and 8 with normal cognition (NC). Classification was made based on clinician assessment supported by a neuropsychological battery, independent of the screening test scores. The Qmci-CN, MoCA-CN, and MMSE-CN screens were administered randomly by a trained rater, blind to the diagnosis.Results: The mean age of the sample was 63 ± 13 years and 61.8% were male. The Qmci-CN had statistically similar diagnostic accuracy in differentiating PSD from NC, an area under the curve (AUC) of 0.94 compared to 0.99 for the MoCA-CN (p = 0.237) and 0.99 for the MMSE-CN (p = 0.293). The Qmci-CN (AUC 0.91), MoCA-CN (AUC 0.94), and MMSE-CN (AUC 0.79) also had statistically similar accuracy in separating PSD from PSCIND. The MoCA-CN more accurately distinguished between PSCIND and normal cognition than the Qmci-CN (p = 0.015). Compared to the MoCA-CN, the administration times of the Qmci-CN (329s vs. 611s, respectively, p < 0.0001) and MMSE-CN (280 vs. 611s, respectively, p < 0.0001) were significantly shorter.Conclusion: The Qmci-CN is accurate in identifying PSD and separating PSD from PSCIND in patients post-stroke following rehabilitation and is comparable to the widely-used MoCA-CN, albeit with a significantly shorter administration time. The Qmci-CN had relatively poor accuracy in identifying PSCIND from NC and hence may lack accuracy for certain subgroups. However, given the small sample size, the study is under-powered to show superiority of one instrument over another. Further study is needed to confirm these findings in a larger sample size and in other settings (countries and languages).

Which cutoff value of the Montreal Cognitive Assessment should be used for post-stroke cognitive impairment? A systematic review and meta-analysis on diagnostic test accuracy

“…A total of 3640 articles were collected, of which 24 were eligible (Figure 1). 18–20,27–47 All these studies were published between 2011 and 2022. The sample size varied from 34 to 521 participants, aged 17–95 years.…”

“…33 Six studies did not report the stroke type clearly. 29,35,38,42,45,47 Seven studies screened cognitive status in the acute/subacute phase, 29,31,32,34,37,41,44 11 in the non-acute phase, 18–20,27,28,30,33,39,40,43,45 and 2 within 3 months of the stroke event. 36,42 The interval between stroke presentation and the assessment ranged from 2 weeks up to 13 years in one study.…”

“…MoCA cutoffs ranged between 15/16 and 29/30. Among these studies, 11 were from Asia, 19,27,29,[32][33][34][35][39][40][41]43 and 13 were from other regions. 18,20,28,30,31,[36][37][38]42,[44][45][46][47] Eight studies included both ischemic and hemorrhagic stroke; 18,19,28,31,36,37,44,46 five included both ischemic stroke and TIA; 27,29,[39][40][41] four included ischemic stroke only; 20,32,34,43 and one included hemorrhagic stroke only.…”

“…36,42 The interval between stroke presentation and the assessment ranged from 2 weeks up to 13 years in one study. 35 Three studies did not report the assessment time clearly. 38,46,47 A summary of the study characteristics is presented in Table 1 in the Data Supplement.…”

Editorial: Update on Vascular Contributions to Age-Related Neurodegenerative Diseases and Cognitive Impairment - Research of ISNVD 2020 Meeting

“…Regarding screening for cognitive impairment after stroke, Xu et al ( 6 ) compared the diagnostic accuracy of a Chinese version of the Quick Mild Cognitive Impairment (Qmci-CN) with a widely-used Chinese version of Montreal Cognitive Assessment (MoCA-CN) and Mini-Mental State Examination (MMSE-CN). They showed that the Qmci-CN is accurate in identifying post-stroke dementia and separating PSD from no-dementia PSCI.…”