Brief screening tests during acute admission in patients with mild stroke are predictive of vascular cognitive impairment 3-6months after stroke

ObjectivesTo determine the prognostic value of brief cognitive screening tests administered in the subacute stroke phase (initial 2weeks) for the detection of significant cognitive impairment 3-6months after stroke, the authors compared the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE).MethodsPatients with ischaemic stroke and transient ischaemic attack were assessed with both MoCA and MMSE within 14days after index stroke, followed by a formal neuropsychological evaluation of seven cognitive domains 3-6months later. Cognitive outcomes were dichotomised as either no-mild (impairment in less than or equal to 2 cognitive domains) or moderate-severe (impairment in greater than or equal to 3 cognitive domains) vascular cognitive impairment. Area under the receiver operating characteristic (ROC) curve analysis was used to compare discriminatory ability.Results300 patients were recruited, of whom 239 received formal neuropsychological assessment 3-6months after the stroke. 60 (25%) patients had moderate-severe VCI. The overall discriminant validity for detection of moderate-severe cognitive impairment was similar for MoCA (ROC 0.85 (95% CI 0.79 to 0.90) and MMSE (ROC 0.83 (95% CI 0.77 to 0.89)), p=0.96). Both MoCA (21/22) and MMSE (25/26) had similar discriminant indices at their optimal cutoff points; sensitivity 0.88 versus 0.88; specificity 0.64 versus 0.67; 70% versus 72% correctly classified. Moreover, both tests had similar discriminant indices in detecting impaired cognitive domains.ConclusionsBrief screening tests during acute admission in patients with mild stroke are predictive of significant vascular cognitive impairment 3-6months after stroke.