White matter microstructural damage and depressive symptoms in patients with mild cognitive impairment and cerebral small vessel disease: the VMCI-Tuscany Study.
OBJECTIVE
Disruption of cortical-subcortical circuits related to small vessel disease (SVD) may predispose to depression in the elderly. We aimed to determine the independent association between white matter (WM) microstructural damage, evaluated with diffusion tensor imaging (DTI), and depressive symptoms in a cohort of elderly subjects with mild cognitive impairment (MCI) and SVD.


METHODS
The vascular mild cognitive impairment (VMCI)-Tuscany Study is an observational multicentric longitudinal study that enrolled patients with MCI and moderate to severe degrees of WM hyperintensities on MRI. Lacunar infarcts, cortical atrophy, medial temporal lobe atrophy, microbleeds, and DTI-derived indices (mean diffusivity, MD and fractional anisotropy, FA) were evaluated on baseline MRI. Geriatric Depression Scale (GDS) (score 0-15) was used to assess depressive symptoms. An extensive neuropsychological battery, Instrumental Activities of Daily Living scale, and the Short Physical Performance Battery were used for cognitive, functional, and motor assessments, respectively.


RESULTS
Seventy-six patients (mean age: 75.1 ± 6.8 years) were included. Univariate analyses showed a significant association between GDS score and both DTI-derived indices (MD: r = 0.307, p = 0.007; FA: r = -0.245; p = 0.033). The association remained significant after adjustment for age, WM hyperintensities severity, global cognitive, functional and motor performances, and antidepressant therapy (MD: r = 0.361, p = 0.002; FA: r = -0.277; p = 0.021).


CONCLUSIONS
These results outline the presence of an association between WM microstructural damage and depressive symptoms in MCI patients with SVD. This relationship does not seem to be mediated by disability, cognitive, and motor impairment, thus supporting the vascular depression hypothesis.
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Marco
M
Pasi
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Anna
A
Poggesi
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Emilia
E
Salvadori
Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy.
Stefano
S
Diciotti
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Laura
L
Ciolli
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Alessandra
A
Del Bene
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Sandro
S
Marini
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Serena
S
Nannucci
Stroke Unit and Neurology, Azienda Ospedaliero Universitaria Careggi, Florence, Italy.
Francesca
F
Pescini
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Raffaella
R
Valenti
"Mario Serio" Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence, Italy.
Andrea
A
Ginestroni
Medical Physics Section, Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.
Nicola
N
Toschi
"Mario Serio" Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence, Italy.
Mario
M
Mascalchi
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.|Institute of Neuroscience, Italian National Research Council, Florence, Italy.
Domenico
D
Inzitari
NEUROFARBA Department, Neuroscience section, University of Florence, Florence, Italy.
Leonardo
L
Pantoni
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001284:Atrophy / Q000473:pathology; D002540:Cerebral Cortex / Q000473:pathology; D059345:Cerebral Small Vessel Diseases / Q000473:pathology*; D060825:Cognitive Dysfunction / Q000473:pathology* / Q000523:psychology*; D003866:Depressive Disorder / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D015577:Geriatric Assessment / Q000379:methods; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D059409:Stroke, Lacunar / Q000473:pathology; D013702:Temporal Lobe / Q000473:pathology; D066127:White Matter / Q000473:pathology* / Q000648:ultrastructure
depressive symptoms; diffusion tensor imaging; mild cognitive impairment; small vessel disease; white matter microstructural damage