Hijazi Z, Yassi N, O’Brien JT, et al. - In Lewy body dementia (LBD), white matter hyperintensities (WMH) are detected, the underlying mechanisms of which need further exploration, because their elevated severity in LBD is not supported by neuropathological assessment of white matter. A similar prevalence of cerebral microbleeds (CMB) has been observed in LBD and Alzheimer disease (AD).

• A total of 63 studies, identified from Medline and Embase, that included participants with dementia with Lewy bodies (DLB) and/or Parkinson disease dementia evaluating cerebrovascular lesions (imaging and pathological studies) were analyzed.

• LBD cases showed an increased severity of white matter changes on magnetic resonance imaging (visualized as WMH), but not neuropathology, vs PD without dementia and age-matched controls.

• In DLB, highly variable CMB prevalence was noted but was broadly similar to AD (0-48%), with a lobar predominance.

• There existed no association between large cortical or small subcortical infarcts or intracerebral haemorrhage and presence of LBD.

• Larger studies are needed to evaluate the impact of cerebrovascular lesions on clinical symptoms, disease progression and outcomes.