OXFORD COGNITIVE SCREEN (OCS) FEASIBILITY IN THE STROKE UNIT SETTING

Objectives: Cognitive screening is not widely used in acute stroke patients, and usually is based on tests developed for dementia. Our aim was to explore the feasibility of a new tool designed for stroke survivors, as the Oxford Cognitive Screen (OCS). Materials: 3–10 days after stroke, patients underwent the OCS, providing a five domain-specific cognitive profile: attention and executive function, language, memory, number processing and praxis. Pre-morbid functional and cognitive status was evaluated by caregiver interview. The National Institute of Health and Stroke Scale (NIHSS) estimated the stroke severity. Method: This cross-sectional study consecutively enrolled stroke patients (both ischemic and hemorrhagic). Exclusion criteria: Pre-morbid cognitive decay, difficulties with the Italian language, visual impairment or other preexisting conditions affecting cognitive status. OCS was considered non-applicable when patients failed the preliminary subtest. Ischemic brain lesions were classified according to the Bamford criteria: Total Anterior Circulation Stroke (TACS), Partial Anterior Circulation Stroke (PACS), Posterior Circulation Syndrome (POCS), Lacunar Syndrome (LACS). Results: Between October and December 2019, 45 out of 62 patients admitted to the Stroke Unit of Poliambulanza Foundation of Brescia were enrolled. Eight patients were non-eligible, 2 died, and 7 did not fit the time window inclusion criteria. Characteristics of the sample were: 43 (95.6%) Italian born, 33 (73.3%) male, 37 (82.2%) with ischemic stroke, mean age (years) 68.00 (DS 15.45), mean initial NIHSS score 7.02 (DS 7.67). Overall, 25 (55.6%) patients had a left sided brain lesion, 13/37 (35%) were affected by TACS, 19 (42.2%) were discharged at home without any cognitive follow-up indications, and 9 (20%) were transferred to neurologic rehabilitation. OCS was applicable in 37/45 (82.2%) patients. Twenty-eight (75.7%) patients showed at least one impaired cognitive domain. At multivariate logistic regression analyses, higher age (OR 1.33; 95% CI 1.02-1.74, p= 0.038) and higher NIHSS score (for every 1-point increase, OR 1.56; 95% CI 1.05-2.33, p= 0.029) were significantly associated to OCS non-applicability, after adjusting for type of stroke (ischemic vs hemorrhagic). In the ischemic subgroup, having TACS (compared to PACS, POCS, or LACS) showed a significant association to OCS non-applicability (OR 13.50, 95%CI 1.19-153.33, p= 0.036). Brain lesion side wasn’t a significant factor. Discussion: OCS confirmed a very good applicability in acute stroke setting, uncontaminated by aphasia and neglect. Age, stroke severity and lesion extension (but not side) emerged as major determinants of its applicability. Conclusions: OCS seems a promising tool in acute stroke setting.