Association Between Periventricular and Subcortical White Matter Hyperintensities and Cognition in a Local Population.

BACKGROUND: White matter hyperintensities (WMH) on fluid-attenuated inversion recovery MRI sequence are regions where fluid from supplying vessels leaks into brain tissue. Some studies have demonstrated an association between WMH and cognitive decline. Given the common WMH risk factors in our local population, the aim of this study is to examine the relationship of overall and regional WMH with cognition in Hamilton, Canada. METHODS: Adults presenting to Hamilton General Hospital in 2020 with a head MRI and cognitive assessment within 6 months of the MRI were included in our cross-sectional study. MRIs were reviewed, assigning a periventricular (PV), a subcortical (SC) and an overall severity score to each based on the Fazekas scale, ranging from 0 to 3. Montreal Cognitive Assessment (MoCA) scores were used as a measure of cognitive function. Patients with confounding diagnoses were excluded. Multiple regression analyses were conducted between WMH and cognitive scores, adjusting for hypertension, diabetes and smoking. RESULTS: Multiple regression models revealed R² values of 0.097, 0.050 and 0.036 for overall, PV and SC WMH with MoCA, respectively. There were negative associations between overall Fazekas scores and MoCA (B = -2.11, p < 0.001), PV scores and MoCA (B = -1.46, p < 0.001) and SC scores and MoCA (B = -1.21, p = 0.002). CONCLUSION: The association between MRI WMH and cognition supports prognostic use for cognitive decline to limit/delay deterioration. Specifically, stronger PV associations prompt research and perhaps development of revised scales prioritizing PV changes. Implementing this into the field of radiology whereby WMH severity and location assessment becomes a standard within brain MRI reports could improve patient outcomes.