White matter dementia then… and now

Abstract

White matter dementia (WMD) is a concept introduced in 1988 to highlight the importance of white matter pathology in producing cognitive dysfunction and dementia. Whereas gray matter, particularly the cerebral cortex, has been primarily investigated in the dementias, subcortical pathology has long been correlated with cognitive loss, and a corticocentric perspective cannot account for the full range of neurobehavioral disorders. Within the subcortical regions, white matter is prominent, accounting for about half the volume of the adult brain, and many white matter diseases, injuries, and intoxications can produce cognitive dysfunction so severe as to justify the term dementia. Recognition of this novel syndrome relied heavily on the introduction of magnetic resonance imaging (MRI) that permitted in vivo visualization of white matter lesions. Neuropsychological studies clarified the clinical presentation of WMD by identifying a profile dominated by cognitive slowing and executive dysfunction, and a precursor syndrome of mild cognitive dysfunction was proposed to identify early cognitive impairment that may later evolve to WMD. As knowledge advanced, the role of white matter in structural connectivity within distributed neural networks was elucidated. In addition, highlighting the frequent commingling of gray and white matter involvement, white matter pathology was associated with neurodegenerative diseases such as Alzheimer's disease and chronic traumatic encephalopathy, with potentially transformative clinical implications. In particular, preventive measures and treatments exploiting white matter restoration and plasticity are gaining much attention. Today, WMD has matured into a concept that not only integrates knowledge from across the spectrum of clinical neuroscience, but also informs new investigations into many perplexing disorders and enables a more complete understanding of brain-behavior relationships.

Association between brain imaging biomarkers and continuous glucose monitoring-derived glycemic control indices in Japanese patients with type 2 diabetes mellitus

“…Severe WMLs have been linked to an increased risk of stroke, all-cause mortality, and dementia 8–11. In fact, patients with severe WMLs had significantly lower MMSE scores than those without severe WMLs in this study, which excluded patients with dementia.…”

“…Severe WMLs have been linked to an increased risk of stroke, all-cause mortality, and dementia. 8–11 In fact, patients with severe WMLs had significantly lower MMSE scores than those without severe WMLs in this study, which excluded patients with dementia. The main etiology of cerebral WMLs is ischemia, and small arteries penetrating the cerebral white matter are predisposed to atherosclerosis.…”

“…The main etiology of cerebral WMLs is ischemia, and small arteries penetrating the cerebral white matter are predisposed to atherosclerosis 9 34. Therefore, risk factors for atherosclerotic diseases, such as hypertension, dyslipidemia, and T2DM, are risk factors for WMLs and stroke 8–10…”

“… 9 34 Therefore, risk factors for atherosclerotic diseases, such as hypertension, dyslipidemia, and T2DM, are risk factors for WMLs and stroke. 8–10 …”

“…Univariate logistic regression analysis was performed with the severity of WMLs as the objective variable and each glycemic control index as the explanatory variable. The progression of WMLs has been reported to be strongly associated with aging, hypertension, and dyslipidemia 8–10. Therefore, a multivariate logistic regression analysis with the severity of WMLs as the objective variable and each glycemic control index and age as explanatory variables was performed using Model 1.…”