Background: Few studies have investigated the correlation between cerebral microbleeds (CMBs), a hemorrhagic imaging marker of cerebral small vessel disease (CSVD), and brain volume.
Objective: We investigated the association between the burden and locations of CMBs and brain volume in community-dwelling populations.
Methods: Data were obtained from 1,029 participants who underwent brain magnetic resonance imaging (MRI) and APOE genotyping. Volumes of the whole brain, subcortical white matter (WM), cortical gray matter (GM), and hippocampus were extracted. Linear regression models were used to investigate the relationship between the CMB burden and their location with structural changes.
Results: Regarding burden, participants with≥3 CMBs had significantly lower whole brain (β= -1.124, p = 0.0133), subcortical WM (β= -1.020, p = 0.0043), and hippocampus (β= -0.015, p = 0.0088) volumes than those without CMBs. Regarding location and burden, the presence of≥3 strictly lobar CMBs was negatively associated with whole brain volume (β= -2.838, p = 0.0088). Additionally, higher CMB burdens in strictly lobar locations or deep/mixed locations were associated with lower subcortical WM volume (β= -1.689, p = 0.0482; β= -0.872, p = 0.0464, respectively). Finally, the presence of≥3 deep/mixed CMBs was associated with lower hippocampus volume (β= -0.018, p = 0.0088), and these associations were independent of other ischemic markers of CSVD. However, the CMB burden and distributional pattern did not correlate with cortical GM volumes.
Conclusion: A higher CMB burden, in specific locations, is associated with decreased brain volumes in community-dwelling populations.
Keywords: brain volumes; cerebral microbleeds; cerebral small vessel disease; hippocampus; white matter.