Association of Cerebral Microbleeds with Cognitive Decline: A Longitudinal Study.

BACKGROUND

The role of cerebral microbleeds (CMBs) in cognitive impairment remains controversial.

OBJECTIVE

To investigate the possible links between the presence, progression, number, and location of CMBs and cognition.

METHODS

We assessed 792 subjects from the Alzheimer's Disease Neuroimaging Initiative who underwent both brain 3 Tesla MRI scans and cognitive testing. The association between CMBs and cognitive change was explored using linear mixed-effects models (LME).

RESULTS

Presence and number of CMBs were associated with memory (β= -0.03, p = 0.015; β= -0.01, p = 0.003), executive function (β= -0.04, p = 0.010; β= -0.01, p = 0.014), and global cognitive function (β= -0.06, p = 0.025; β= -0.03, p < 0.001). Progression of CMBs showed significant negative associations with executive function (β= -0.05, p = 0.025) and global cognitive function (β= -0.12, p = 0.015). The relations with cognitive performance (memory, executive function and global cognitive function) were mainly driven by lobar CMBs (β= -0.03, p = 0.041; β= -0.04, p = 0.010; β= -0.07, p = 0.029, respectively), especially those located in temporal lobe (β= -0.08, p = 0.027; β= -0.13, p = 0.001; β= -0.26, p < 0.001, respectively). Furthermore, white matter hyperintensities may mediate the association between CMBs and cognition.

CONCLUSION

The presence, progression, number, and location of CMBs, especially those located in temporal lobe, are associated with cognitive decline. These findings suggest CMBs play a role in cognitive impairment.