Nicole A Kochan1, David Bunce2, Sarah Pont3, John D Crawford3, Henry Brodaty4, Perminder S Sachdev5. 1. CHeBA, Centre for Healthy Brain Ageing, School of Psychiatry, UNSW Medicine, The University of New South Wales, Sydney, New South Wales, Australia; Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, New South Wales, Australia. Electronic address: n.kochan@unsw.edu.au. 2. School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom. 3. CHeBA, Centre for Healthy Brain Ageing, School of Psychiatry, UNSW Medicine, The University of New South Wales, Sydney, New South Wales, Australia. 4. CHeBA, Centre for Healthy Brain Ageing, School of Psychiatry, UNSW Medicine, The University of New South Wales, Sydney, New South Wales, Australia; Dementia Collaborative Research Centre, School of Psychiatry, UNSW Medicine, The University of New South Wales, Sydney, New South Wales, Australia; Academic Department for Old Age Psychiatry, Prince of Wales Hospital, Randwick, New South Wales, Australia. 5. CHeBA, Centre for Healthy Brain Ageing, School of Psychiatry, UNSW Medicine, The University of New South Wales, Sydney, New South Wales, Australia; Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, New South Wales, Australia.
Abstract
OBJECTIVE: To examine the utility of intraindividual variability of reaction times (IIVRT) and mean reaction time (RT) as behavioral markers of incident all-cause dementia. METHODS: A longitudinal cohort study followed biennially for 4 years, the community-based Sydney Memory and Ageing Study, 861 initially nondemented participants aged 70-90. Incident all-cause dementia determined by consensus, RT measures from simple and complex tasks, Mini-Mental State Exam and neuropsychological tests, Geriatric Depression Scale and Goldberg Anxiety Scale, cardiovascular risk score, apolipoprotein ε4 status, and the Bayer ADL Scale were used. Associations of baseline IIVRT and mean RT with time to dementia were evaluated with hazard ratios (HRs) using Cox proportional-hazards models with and without controlling for dementia risk factors. RESULTS: Forty-eight cases developed dementia. Greater complex IIVRT predicted a 40% (HR: 1.43) and mean RT a 50%-60% (simple RT: HR 1.53; complex RT: HR 1.59) per standard deviation increased risk of developing dementia, remaining significant after controlling for age, education, sex, general cognitive function, mood, cerebrovascular disease, and genetic susceptibility. Prediction of incident dementia using demographical information and RT measures combined was comparable with several traditional neuropsychological measures (AUC 0.75), although lower than a full neuropsychological battery (AUC 0.90). Prediction of functional decline by RT measures combined was equal to the neuropsychological battery (multiple Rs of .233 and .238, respectively). CONCLUSION: Brief RT measures provided information on risk of imminent dementia and functional decline within 4 years in older adults at a population level, with mean RT the stronger predictor.
OBJECTIVE: To examine the utility of intraindividual variability of reaction times (IIVRT) and mean reaction time (RT) as behavioral markers of incident all-cause dementia. METHODS: A longitudinal cohort study followed biennially for 4 years, the community-based Sydney Memory and Ageing Study, 861 initially nondemented participants aged 70-90. Incident all-cause dementia determined by consensus, RT measures from simple and complex tasks, Mini-Mental State Exam and neuropsychological tests, Geriatric Depression Scale and Goldberg Anxiety Scale, cardiovascular risk score, apolipoprotein ε4 status, and the Bayer ADL Scale were used. Associations of baseline IIVRT and mean RT with time to dementia were evaluated with hazard ratios (HRs) using Cox proportional-hazards models with and without controlling for dementia risk factors. RESULTS: Forty-eight cases developed dementia. Greater complex IIVRT predicted a 40% (HR: 1.43) and mean RT a 50%-60% (simple RT: HR 1.53; complex RT: HR 1.59) per standard deviation increased risk of developing dementia, remaining significant after controlling for age, education, sex, general cognitive function, mood, cerebrovascular disease, and genetic susceptibility. Prediction of incident dementia using demographical information and RT measures combined was comparable with several traditional neuropsychological measures (AUC 0.75), although lower than a full neuropsychological battery (AUC 0.90). Prediction of functional decline by RT measures combined was equal to the neuropsychological battery (multiple Rs of .233 and .238, respectively). CONCLUSION: Brief RT measures provided information on risk of imminent dementia and functional decline within 4 years in older adults at a population level, with mean RT the stronger predictor.
Authors: Aurélie L Manuel; David Foxe; Nathan Bradshaw; Nicholas J Cordato; John R Hodges; James R Burrell; Olivier Piguet Journal: J Neurol Date: 2019-03-05 Impact factor: 4.849
Authors: Nicole A Kochan; David Bunce; Sarah Pont; John D Crawford; Henry Brodaty; Perminder S Sachdev Journal: PLoS One Date: 2017-08-09 Impact factor: 3.240
Authors: Roberta Ferrucci; Simona Mrakic-Sposta; Simona Gardini; Fabiana Ruggiero; Maurizio Vergari; Francesca Mameli; Andrea Arighi; Marco Spallazzi; Federica Barocco; Giovanni Michelini; Anna Margherita Pietroboni; Laura Ghezzi; Giorgio Giulio Fumagalli; Giordano D'Urso; Paolo Caffarra; Elio Scarpini; Alberto Priori; Sara Marceglia Journal: Front Behav Neurosci Date: 2018-10-29 Impact factor: 3.558
Authors: João Bento-Torres; Natáli Valim Oliver Bento-Torres; Chelsea M Stillman; George A Grove; Haiqing Huang; Fatma Uyar; Jennifer C Watt; Mariegold E Wollam; Kirk I Erickson Journal: J Sport Health Sci Date: 2019-03-20 Impact factor: 7.179
Authors: Beth E Snitz; Dana L Tudorascu; Zheming Yu; Elizabeth Campbell; Brian J Lopresti; Charles M Laymon; Davneet S Minhas; Neelesh K Nadkarni; Howard J Aizenstein; William E Klunk; Sandra Weintraub; Richard C Gershon; Ann D Cohen Journal: Alzheimers Dement (Amst) Date: 2020-05-15