The presence of cerebral microbleeds is associated with cognitive impairment in Parkinson's disease

Background: Cerebral microbleeds (CMBs) are often observed in Parkinson's disease (PD); however, their association with cognitive decline has been unclear. We performed a retrospective analysis of 124 cases of clinically diagnosed PD to determine the association between the presence of CMBs and cognitive decline. Results: Of the 124 participants, 21 (16.9%) was diagnosed as PDD in this cohort. CMBs were observed significantly more frequently in the PDD than in the PD (47.6% vs 7.8%, P < .001). The presence of both deep/infratentorial (40% vs 14.9%, P < .05) and strictly lobar (75% vs 12.9%, P < .001) CMBs were associated with PDD. The values of cognitive scales such as Mini-Mental State Examination and the Hasegawa Dementia Scale revised, were also significantly lower in the presence of each type of CMB. A multivariable logistic regression analysis showed the presence of strictly lobar CMBs as well as a male gender, orthostatic hypotension, peri-ventricular hyperintensity on magnetic resonance imaging were significantly associated with PDD in this cohort. Conclusions: This study showed the presence of CMBs, especially strictly lobar type, was strongly associated with PDD. We suspect that the burden of small vessel disease and cerebral amyloid angiopathy may be related to the development of cognitive decline in PD, and a prospective study enrolling more cases is warranted.