Cambridge Cognitive Examination and Hachinski Ischemic Score as predictors of MRI confirmed pathology in dementia: A cross-sectional study.

Abstract

Dementia is diagnosed through a combination of clinical assessment, cognitive assessment tools and neuroimaging. The aim of this retrospective, naturalistic study was to explore the association between the clinical assessment tools used in a memory clinic and the findings of Magnetic Resonance Imaging (MRI) scans in patients with dementia. Data were collected through routine clinical practice for all patients assessed at a memory assessment clinic in East Sussex, UK. Included patients had an MRI scan and received a formal diagnosis of dementia. Multinomial logistic regression was used to investigate the associations between atrophy on MRI with age, gender, Cambridge Cognitive Examination (CAMCOG) and Hachinski Ischemic Score (HIS). Ordinal logistic regression was used to study the associations between vascular findings on MRI with age, gender, CAMCOG and HIS. Because of the distribution of HIS scores a cut-off of 1 or greater was used in the regression analysis. Male gender was associated with an increased likelihood of moderate atrophy (relative risk ratio (RRR)=1.99, 95% confidence interval (CI)=1.04-3.82), severe atrophy (RRR=3.04, 95%CI=1.38-6.68) and regional atrophy (RRR=2.25, 95%CI=1.26-4.00) on MRI. An increase of one point on the CAMCOG was associated with a decreased risk of regional atrophy (RRR=0.98, 95%CI=0.96-1.00) on MRI. There were no significant associations between age, or HIS, and atrophy on MRI. An increase in age of one year was associated with an increase in severity of vascular pathology reported on MRI (OR=1.08, 95%CI=1.05-1.12). Male gender was associated with reduced severity of vascular pathology reported on MRI (OR=0.53, 95%CI=0.36-0.78). There were no associations between CAMCOG, or HIS, and vascular pathology on MRI. Our data show that CAMCOG was associated with MRI findings of regional atrophy and vascular pathology was greater in older patients. We highlight the importance of using a multi-modal approach to dementia diagnosis.