Stability of estimated premorbid cognitive ability over time after minor stroke and its relationship with post-stroke cognitive ability

McHutchison, C. A., Chappell, F. M., Makin, S., Shuler, K., Wardlaw, J. M. and Cvoro, V. (2019) Stability of estimated premorbid cognitive ability over time after minor stroke and its relationship with post-stroke cognitive ability. Brain Sciences, 9(5), 117. (doi: 10.3390/brainsci9050117) (PMID:31121963) (PMCID:PMC6562568)

Abstract

Considering premorbid or “peak” adult intelligence (IQ) is important when examining post-stroke cognition. The stability of estimated premorbid IQ and its relationship to current cognitive ability in stroke is unknown. We investigated changes in estimated premorbid IQ and current cognitive ability up to three years post-stroke. Minor stroke patients (NIHSS < 8) were assessed at one to three months, one and three years’ post-stroke. The National Adult Reading Test (NART) and Addenbrooke’s Cognitive Examination-Revised (ACE-R) were used to estimate premorbid IQ (NART IQ) and current cognitive ability respectively at each time-point. Baseline demographics, vascular and stroke characteristics were included. Of the 264 patients recruited (mean age 66), 158 (60%), 151 (57%), and 153 (58%) completed cognitive testing at each time-point respectively. NART IQ initially increased (mean difference (MD) = 1.32, 95% CI = 0.54 to 2.13, p < 0.001) before decreasing (MD = −4.269, 95% CI = −5.12 to −3.41, p < 0.001). ACE-R scores initially remained stable (MD = 0.29, 95% CI = −0.49 to 1.07, p > 0.05) before decreasing (MD = −1.05, 95% CI = −2.08 to −0.01, p < 0.05). Adjusting for baseline variables did not change the relationship between NART IQ and ACE-R with time. Increases in NART IQ were associated with more education. For ACE-R, older age was associated with declines, and higher NART IQ and more education was associated with increases. Across 3 years, we observed fluctuations in estimated premorbid IQ and minor changes in current cognitive ability. Future research should aim to identify variables associated with these changes. However, studies of post-stroke cognition should account for premorbid IQ.

• Item Type: Articles
• Additional Information: This research was funded by Chest Heart Stroke Scotland (Ref No: Res 14/A157; NHS Research Scotland; The Wellcome Trust (WT088134/Z/09/A); Mrs Gladys Row Fogo Charitable Trust (AD.Row4.35); the European Union Horizon 2020 (PHC-03-15, project No 666881, ‘SVDs@target’), the Fondation Leducq Transatlantic Network of Excellence for the Study of Perivascular Spaces in Small Vessel Disease (Ref No: 16 CVD 05); the Medical Research Council through the UK Dementia Research Institute; the Scottish Funding Council through the Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Initiative (http://www.sinapse.ac.uk).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Makin, Dr Stephen
• Authors: McHutchison, C. A., Chappell, F. M., Makin, S., Shuler, K., Wardlaw, J. M., and Cvoro, V.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: Brain Sciences
• Publisher: MDPI
• ISSN: 2076-3425
• ISSN (Online): 2076-3425
• Published Online: 22 May 2019
• Copyright Holders: Copyright © 2019 by the authors
• First Published: First published in Brain Sciences 9(5):117
• Publisher Policy: Reproduced under a Creative Commons license