Introduction: Cerebral White matter hyperintensities(WMH) are frequent findings on MRI scan. They are well known to correlate with vascular cognitive impairment(VCI). However, controversies still remain about the relationship between WMH locations and cognitive function across studies.
Hypothesis: Periventricular WMHs(PWH) rather than deep WMHs(DWH) are associated with cognitive decline in VCI.
Methods: Fifty-nine subjects with WMHs on MRI were divided into three groups, normal control(NC), mild cognitive impairment(MCI) and vascular dementia(VaD), according to clinical manifestation and neuropsychological performance. WMH volumes were evaluated by Fazekas rating scale and segmental volumetric. Correlations between cognitive performance and WMH volumes were determined in virtue of Spearman correlation analysis. Receiver operator characteristic (ROC) curves were generated to define the classification cut-off value of WMH volumes for distinguishing VCI versus normal controls. Multiple linear regression analysis was used to predict cognitive performance with WMH volumes and locations after adjusting for sex ,age and education level.
Results: Cognitive capacities were gradually declined from NC through MCI to VaD patients while WMH volumes and Fazekas scores altered oppositely. Both PWH and DWH volumes and Fazekas scores were correlated with cognitive performance, and moreover, WMH volumes were correlated with Fazekas scores. ROC analysis showed a cut-off value of PWH rather than DWH to distinguish VCI from NC(AUC=0.745 and 0.635, p=0.001 and 0.076, respectively). Linear regression analysis demonstrated that only PWH volumes were associated with cognitive performance(p < 0.001).
Conclusion: Our study demonstrate that PWHs are independent predictors for vascular contribution in white matter lesions and suggest clinicians that PWH should be emphasized on evaluating vascular cognitive impairment related with white matter load.