Abstract
Many previous studies have revealed structural and functional abnormalities in patients with the subcortical vascular mild cognitive impairment (svMCI). Although depression symptoms were suggested to serve as a potential marker of conversion to dementia in patients with svMCI, whether these disruptions or other new findings will be identified in the svMCI comorbid with depression symptoms has not been established. In the current study, we combined voxel-based morphometry (VBM) and the resting-state functional magnetic resonance imaging (fMRI) to investigate the structural and functional disruptions in the svMCI with and without depression symptoms using a cohort of 18 svMCI with depression symptoms (svMCI+D), 17 svMCI without depression symptoms (svMCI−D), and 23 normal controls (NC). As a result, we identified significantly decreased gray matter density in the left parahippocampus (ParaHIPP.L), the right hippocampus (HIPP.R), and the right middle cingulate cortex (MCC.R) in both svMCI+D and svMCI−D compared to NC. Most importantly, we also identified increased gray matter density in the MCC.R accompanied by increased resting-state functional connectivity (RSFC) with right parahippocampus (ParaHIPP.R) in the svMCI+D compared to svMCI−D. Moreover, the gray matter density of MCC.R and ParaHIPP.L was correlated with cognitive impairments and depression symptoms in the svMCI, respectively. In conclusion, these results extended previous studies and added weight to considerations of depression symptoms in the svMCI. Moreover, we suggested that a processing loop associated with HIPP, ParaHIPP, and MCC might underlie the mechanism of depression symptoms in the svMCI.
Highlights
The subcortical vascular mild cognitive impairment is a nonamnestic subtype of MCI, which is characterized by extensive white matter hyperintensities (WMH) and multiple lacunar infarctions on magnetic resonance imaging (MRI; Frisoni et al, 2002)
We found significantly increased mean gray matter density of the middle cingulate cortex (MCC).R in the subcortical vascular mild cognitive impairment (svMCI)+D compared to the svMCI−D (Figure 1B)
We found significantly increased resting-state functional connectivity (RSFC) between the MCC.R and right parahippocampus (ParaHIPP.R) in both the svMCI+D and svMCI−D groups compared to the normal controls (NC) (Figure 2)
Summary
The subcortical vascular mild cognitive impairment (svMCI) is a nonamnestic subtype of MCI, which is characterized by extensive white matter hyperintensities (WMH) and multiple lacunar infarctions on magnetic resonance imaging (MRI; Frisoni et al, 2002). More and more attention was paid to svMCI since it is regarded as a prodromal stage of Alterations in svMCI With Depression subcortical vascular dementia (SVaD; Frisoni et al, 2002; Seo et al, 2010; Kim et al, 2011) but is potentially reversible by managing the risk factors and drug treatments (Ravaglia et al, 2006; Jak et al, 2009). A study reported that the prevalence of depression was highest in MCI (up to 18.8%) and was associated with different cognitive domains (Vloeberghs et al, 2018). Depression symptoms, even at minimal severity, have been reported to be associated with progression from MCI to dementia (Gabryelewicz et al, 2007; Teng et al, 2007; Palmer et al, 2010; Rosenberg et al, 2013). It is important and useful to investigate the structural and functional disruptions in the svMCI with and without depression symptoms (svMCI+D and svMCI−D, respectively)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
