Predicting the time of conversion to MCI in the elderly. Role of verbal expression and learning, Neurology, 3rd Nov. 2009, Vol.73 (18) pp1436-1442
Abderrahim Oulhaj PhD, Gordon K. Wilcock DM, A. David Smith FMedSci*, and Celeste A. de Jager PhD
From the University of Oxford, Oxford Project to Investigate Memory and Ageing (OPTIMA), John Radcliffe Hospital (A.O., G.K.W., A.D.S., C.A.d.J.), Oxford; and Department of Physiology, Anatomy and Genetics (A.D.S.) and Nuffield Department of Clinical Medicine (G.K.W.), University of Oxford, UK
Abstract:
Background: Increasing awareness that minimal or mild cognitive impairment (MCI) in the elderly may be a precursor of dementia has led to an increase in the number of people attending memory clinics. We aimed to develop a way of predicting the period of time before cognitive impairment occurs in community-dwelling elderly. The method is illustrated by the use of simple tests of different cognitive domains.
Methods: A cohort of 241 normal elderly volunteers was followed for up to 20 years with regular assessments of cognitive abilities using the Cambridge Cognitive Examination (CAMCOG); 91 participants developed MCI. We used interval-censored survival analysis statistical methods to model which baseline cognitive tests best predicted the time to convert to MCI.
Results: Out of several baseline variables, only age and CAMCOG subscores for expression and learning/memory were predictors of the time to conversion. The time to conversion was 14% shorter for each 5 years of age, 17% shorter for each point lower in the expression score, and 15% shorter for each point lower in the learning score. We present in tabular form the probability of converting to MCI over intervals between 2 and 10 years for different combinations of expression and learning scores.
Conclusion: In apparently normal elderly people, subtle measurable cognitive deficits that occur within the normal range on standard testing protocols reliably predict the time to clinically relevant cognitive impairment long before clinical symptoms are reported.
Lancashire Care staff can request the full-text of this paper, email: susan.jennings@lancashirecare.nhs.uk
Filed under: alzheimers, dementia, memory | Tagged: cambridge, CAMCOG, dementia, early stages, memory, research, study, tests
