Background and purpose: It has been suggested that poststroke dementia is associated with a higher risk of stroke recurrence. Leukoaraiosis, however, might be a confounding factor because it is a risk factor for stroke recurrence and cognitive decline. Our aim was to determine the influence of prestroke and poststroke dementia on the 3-year risk of stroke recurrence.
Methods: We evaluated prestroke cognitive functions in 202 stroke patients >or=40 years of age using the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), with a cutoff of 104 for the diagnosis of dementia. Patients were followed up for 3 years. Dementia was diagnosed on the basis of International Classification of Diseases, 10th revision, criteria in survivors who underwent a neurologist visit or from the IQCODE score in survivors who did not. The severity of leukoaraiosis was assessed with a visual rating scale on CT scans without contrast performed at the acute stage of stroke. At each follow-up contact, stroke recurrences were recorded.
Results: During 385 person-years of follow-up, a total of 29 patients developed 33 stroke recurrences, resulting in an incidence rate of 8.6 per 100 person-years. We did not find any influence of dementia on the risk of stroke recurrence. Leukoaraiosis, however, was a strong predictor of stroke recurrence within 3 years after stroke.
Conclusions: Dementia was not a predictor of stroke recurrence, but leukoaraiosis was strongly associated with stroke recurrence. Special attention in the secondary prevention of stroke must be given to patients with leukoaraiosis with or without dementia.