Association between white matter lesions and cerebral Aβ burden

Introduction White matter lesions (WMLs), detected as hyperintensities on T2-weighted MRI, represent small vessel disease in the brain and are considered a potential risk factor for memory and cognitive impairment in older adults. The purpose of this study was to evaluate the association between WMLs and cerebral amyloid-beta (A(beta) burden in patients with cognitive impairment. Methods A total of 83 patients with cognitive impairment, who underwent brain MRI and F-18 florbetaben PET, were included prospectively: 19 patients were cognitively unimpaired, 30 exhibited mild cognitive impairment (MCI), and 34 exhibited dementia. The Fazekas scale was used to quantify WMLs on T2-weighted brain MR images. Cerebral A beta burden was quantitatively estimated using volume-of-interest analysis. Differences in cerebral A beta burden were evaluated between low-WML (Fazekas scale <= 1) and high-WML (Fazekas scale >= 2) groups. The relationship between the Fazekas rating and cerebral A beta burden was evaluated using linear regression analysis after adjusting for age and sex. Results In the overall cohort, the high-WML group exhibited significantly higher A beta burden compared with the low-WML group (P=0.011) and cerebral A beta burden was positively correlated with Fazekas rating(beta= 0.299, P= 0.006). In patients with MCI, the high-WML group exhibited significantly higher A beta burden compared with the low-WML group (P= 0.019) and cerebral A beta burden was positively correlated with Fazekas rating (beta = 0.517, P= 0.003). Conclusion The presence of WMLs was associated with cerebral A beta burden in patients with MCI. Our findings suggest that small vessel disease in the brain is related to Alzheimer's disease pathology.