Background and purpose: The importance of executive dysfunction is increasingly recognized in the dementia syndrome. Although executive dysfunction has been associated with subcortical ischemic lesions, it may not be unique to VCI or to its clinical subtypes.
Methods: Secondary analysis of the CIVIC study, a multi-centre memory clinic cohort study. An executive dysfunction index variable was created using 30 items from the clinical evaluation.
Results: Of 1347 patients, 151 had a baseline diagnosis of no cognitive impairment (NCI), 463 had AD, 324 had VCI, 97 had vascular cognitive impairment not dementia (VCI-ND) and 253 had non-vascular CIND. Those with VCI and AD had higher mean executive dysfunction index values than those with NCI (F=160.2, p<0.01). Within the VCI subtypes, people with VaD and mixed dementia had the highest mean executive dysfunction index values (F=92.5, p<0.01). Higher executive dysfunction index values were significantly correlated with lower MMSE scores (R=0.70, p<0.01), higher Functional Rating Scale scores (R=0.77, p<0.01) and higher Geriatric Depression Score values (R=0.11, p<0.01). Compared to those who had a lower burden of executive dysfunction, patients with more executive dysfunction (index values >=0.2) were more likely to be institutionalized (HR=5.2, p<0.01) or to die (HR=2.4, p<0.01) during the next 30 months.
Conclusions: Executive dysfunction is common in both AD and VCI. It is associated with poor performance on other measures of cognition and function. The presence of executive dysfunction is associated with worse near-term outcomes.