Influences of lobar gray matter and white matter lesion load on cognition and mood

Abstract

Depressed mood is a frequent co-morbidity of dementia suggesting that they might share a common neuropathological substrate. Gray matter (GM) atrophy and white matter lesions (WML) have been described in both conditions. Our aims were to determine the relationship of GM and WML with cognition and depressed mood in the same population. Structural brain images were obtained from 42 controls, 20 Alzheimer’s disease (AD) patients and 32 subjects with cognitive impairment/dementia due to subcortical cerebrovascular disease (vascCIND/IVD) and segmented to obtain lobar GM, white matter and WML volumes. Lobar WML had a negative effect on GM in all lobes in controls, on frontal, parietal and occipital GM in AD and on frontal GM in vascCIND/IVD. Frontal, temporal and hippocampal GM were associated with cognitive functions and frontal WML load with depressed mood. Cognitive function is associated with GM atrophy and depressed mood is associated with frontal WML. This indicates that although both often occur together depressed mood and cognitive impairment are caused by different pathological correlates.

Erken Evre Alzheimer Hastalığında İzlenen Ak Madde Hiperintensitelerinin Depresif Semptomlar ve Günlük Yaşam Aktiviteleri ile İlişkisi

“…Similar to our study, there are other studies in which HWMs were found to be related only with depressive mood, but not with cognitive state (13). An explanation of lack of a relation may be the fact that the patients included in the study were early stage patients with cognitive findings and HWMs do not lead to an additional cognitive disorder in this stage.…”

“…Recognition of these symptoms which response better compared to the others and initiation of appropriate treatment at the appropriate time carry considerable importance in terms of the prognosis of the disease, the burden of the caretaker and socioeconomic burden. The relation between frontal HWMs and depressive mood which was found in this study by MRI was also shown in a recent study performed by Mueller et al In this study, white matter lesions were examined in the lobes by automated analysis methods and right-left hemisphere differentiation was not made (13). In contrast, this relation was not observed in a series involving patients with frontotemporal dementia and vascular dementia other than Alzheimer's disease (14).…”

Alterations of the cerebral cortex in sporadic small vessel disease: A systematic review of in vivo MRI data

“…However, a normal cognitive status was requested in all studies and a normal MRI (definition of which varied among studies) in all but one study. 33 Sample sizes in these five studies were small (mean number of patients: 29, mean number of controls: 52). Mean age was about 70 years in four studies 10,30,32,33 and close to 60 years in one.…”

“…For instance, the presence of focal neurological signs was mandatory in three studies, 30,32,34 but not in the two others, 10,33 and the presence of cortical infarcts was an explicit exclusion criterion in three studies 10,30,34 but not in two. 32,33 In one study, post-mortem data were available in 4 of 18 cases and dementia was definitively attributed to SVD in all cases. 10 By contrast, in the other studies, no attempt was made to exclude concomitant AD.…”

“…10 By contrast, in the other studies, no attempt was made to exclude concomitant AD. 30,[32][33][34] Inclusion criteria for controls were also highly variables. However, a normal cognitive status was requested in all studies and a normal MRI (definition of which varied among studies) in all but one study.…”