Prevalence of subcortical vascular lesions and association with executive function in mild cognitive impairment subtypes.

BACKGROUND AND PURPOSE Subcortical hyperintensities (SH) have not been systematically evaluated in mild cognitive impairment (MCI). We sought to describe their frequency and distribution, and to test their association with cognitive characteristics in MCI patients. METHODS We performed standardized neuropsychological tests and an MRI scan in 170 consecutive MCI patients. Medial temporal lobe atrophy and SH, including periventricular, lobar white matter, basal ganglia and infratentorial hyperintensities, were assessed with visual semiquantitative scales. RESULTS The median age was 68.1 years (range: 45.5 to 87.0), and the median Mini-Mental State Examination score 28.0 (range: 26.0 to 30.0). MCI subtypes were amnestic single domain (21.2%), amnestic multiple domain (52.3%), nonamnestic single domain (21.8%), and nonamnestic multiple domain (4.7%). SH were found in 157 patients (92.6%); periventricular hyperintensities (80.6%) and lobar white matter hyperintensities (83.5%) were the most prominent locations. There was no association between SH and MCI subtypes. Executive dysfunction was independently associated with SH (odds ratio=2.53, 95% CI: 1.20 to 5.32), periventricular hyperintensities (odds ratio=2.51, 95% CI: 1.13 to 5.55), and white matter hyperintensities (odds ratio=2.08, 95% CI: 1.01 to 4.25). CONCLUSIONS The prevalence of SH is high in MCI patients, irrespective of MCI subtypes. SH (especially periventricular hyperintensities, and lobar white matter hyperintensities) are associated with executive dysfunction.