%0 Journal Article %J J Alzheimers Dis %D 2022 %T Does Loss of Integrity of the Cingulum Bundle Link Amyloid-β Accumulation and Neurodegeneration in Alzheimer's Disease? %A Vlegels, Naomi %A Ossenkoppele, Rik %A van der Flier, Wiesje M %A Koek, Huiberdina L %A Reijmer, Yael D %A Wisse, Laura Em %A Biessels, Geert Jan %X

BACKGROUND: Alzheimer's disease is characterized by the accumulation of amyloid-β (Aβ) into plaques, aggregation of tau into neurofibrillary tangles, and neurodegenerative processes including atrophy. However, there is a poorly understood spatial discordance between initial Aβ deposition and local neurodegeneration.

OBJECTIVE: Here, we test the hypothesis that the cingulum bundle links Aβ deposition in the cingulate cortex to medial temporal lobe (MTL) atrophy.

METHODS: 21 participants with mild cognitive impairment (MCI) from the UMC Utrecht memory clinic (UMCU, discovery sample) and 37 participants with MCI from Alzheimer's Disease Neuroimaging Initiative (ADNI, replication sample) with available Aβ-PET scan, T1-weighted and diffusion-weighted MRI were included. Aβ load of the cingulate cortex was measured by the standardized uptake value ratio (SUVR), white matter integrity of the cingulum bundle was assessed by mean diffusivity and atrophy of the MTL by normalized MTL volume. Relationships were tested with linear mixed models, to accommodate multiple measures for each participant.

RESULTS: We found at most a weak association between cingulate Aβ and MTL volume (added R2 <0.06), primarily for the posterior hippocampus. In neither sample, white matter integrity of the cingulum bundle was associated with cingulate Aβ or MTL volume (added R2 <0.01). Various sensitivity analyses (Aβ-positive individuals only, posterior cingulate SUVR, MTL sub region volume) provided similar results.

CONCLUSION: These findings, consistent in two independent cohorts, do not support our hypothesis that loss of white matter integrity of the cingulum is a connecting factor between cingulate gyrus Aβ deposition and MTL atrophy.

%B J Alzheimers Dis %V 89 %P 39-49 %8 2022 Aug 30 %G eng %N 1 %R 10.3233/JAD-220024 %0 Journal Article %J J Alzheimers Dis %D 2019 %T The Clinical Phenotype of Vascular Cognitive Impairment in Patients with Type 2 Diabetes Mellitus. %A Groeneveld, Onno N %A Moneti, Costanza %A Heinen, Rutger %A de Bresser, Jeroen %A Kuijf, Hugo J %A Exalto, Lieza G %A Boomsma, Jooske M F %A Kappelle, L Jaap %A Barkhof, Frederik %A Prins, Niels D %A Scheltens, Philip %A van der Flier, Wiesje M %A Biessels, Geert Jan %X

BACKGROUND: Type 2 diabetes mellitus (T2DM) increases the risk of vascular cognitive impairment (VCI). It is unknown which type of vascular lesions and co-morbid etiologies, in particular Alzheimer's disease pathology, are associated with T2DM in patients with VCI, and how this relates to cognition and prognosis.

OBJECTIVE: To compare brain MRI and cerebrospinal fluid (CSF) markers, cognition, and prognosis in patients with possible VCI with and without T2DM.

METHODS: We included 851 memory clinic patients with vascular brain injury on MRI (i.e., possible VCI) from a prospective cohort study (T2DM: n = 147, 68.4±7.9 years, 63% men; no T2DM: n = 704, 67.6±8.5 years, 52% men). At baseline, we assessed between-group differences in brain MRI abnormalities, CSF markers of Alzheimer's disease, and cognitive profile. After two years follow-up, we compared occurrence of cognitive decline, stroke, and death.

RESULTS: The distribution of clinical diagnoses did not differ between patients with and without T2DM. T2DM patients had more pronounced brain atrophy (total and white matter volume), and more lacunar infarcts, whereas microbleeds were less common (all p <  0.05). CSF amyloid-β levels were similar between the groups. T2DM patients performed worse on working memory (effect size: - 0.17, p = 0.03) than those without, whereas performance on other domains was similar. During follow-up, risk of further cognitive decline was not increased in T2DM.∥Conclusion: In patients with possible VCI, presence of T2DM is related to more pronounced brain atrophy and a higher burden of lacunar infarcts, but T2DM does not have a major impact on cognitive profile or prognosis.∥.

%B J Alzheimers Dis %V 68 %P 311-322 %8 2019 Mar 12 %G eng %N 1 %R 10.3233/JAD-180914 %0 Journal Article %J J Alzheimers Dis %D 2018 %T Association of Cerebrospinal Fluid (CSF) Insulin with Cognitive Performance and CSF Biomarkers of Alzheimer's Disease. %A Geijselaers, Stefan L C %A Aalten, Pauline %A Ramakers, Inez H G B %A De Deyn, Peter Paul %A Heijboer, Annemieke C %A Koek, Huiberdina L %A OldeRikkert, Marcel G M %A Papma, Janne M %A Reesink, Fransje E %A Smits, Lieke L %A Stehouwer, Coen D A %A Teunissen, Charlotte E %A Verhey, Frans R J %A van der Flier, Wiesje M %A Biessels, Geert Jan %K Aged %K Alzheimer Disease %K Amyloid beta-Peptides %K Apolipoprotein E4 %K Brain %K Cognition Disorders %K Female %K Humans %K Insulin %K Male %K Mental Status Schedule %K Middle Aged %K Neuropsychological Tests %K Peptide Fragments %K Signal Transduction %K tau Proteins %X

BACKGROUND: Abnormal insulin signaling in the brain has been linked to Alzheimer's disease (AD).

OBJECTIVE: To evaluate whether cerebrospinal fluid (CSF) insulin levels are associated with cognitive performance and CSF amyloid-β and Tau. Additionally, we explore whether any such association differs by sex or APOE ɛ4 genotype.

METHODS: From 258 individuals participating in the Parelsnoer Institute Neurodegenerative Diseases, a nationwide multicenter memory clinic population, we selected 138 individuals (mean age 66±9 years, 65.2% male) diagnosed with subjective cognitive impairment (n = 45), amnestic mild cognitive impairment (n = 44), or AD (n = 49), who completed a neuropsychological assessment, including tests of global cognition and memory performance, and who underwent lumbar puncture. We measured CSF levels of insulin, amyloid-β1-42, total (t-)Tau, and phosphorylated (p-)Tau.

RESULTS: CSF insulin levels did not differ between the diagnostic groups (p = 0.136). Across the whole study population, CSF insulin was unrelated to cognitive performance and CSF biomarkers of AD, after adjustment for age, sex, body mass index, diabetes status, and clinic site (all p≥0.131). Importantly, however, we observed effect modification by sex and APOE ɛ4 genotype. Specifically, among women, higher insulin levels in the CSF were associated with worse global cognition (standardized regression coefficient -0.483; p = 0.008) and higher p-Tau levels (0.353; p = 0.040). Among non-carriers of the APOE ɛ4 allele, higher CSF insulin was associated with higher t-Tau (0.287; p = 0.008) and p-Tau (0.246; p = 0.029).

CONCLUSION: Our findings provide further evidence for a relationship between brain insulin signaling and AD pathology. It also highlights the need to consider sex and APOE ɛ4 genotype when assessing the role of insulin.

%B J Alzheimers Dis %V 61 %P 309-320 %8 2018 %G eng %N 1 %1 http://www.ncbi.nlm.nih.gov/pubmed/29154275?dopt=Abstract %R 10.3233/JAD-170522 %0 Journal Article %J J Alzheimers Dis %D 2018 %T Automated Multi-Atlas Segmentation of Hippocampal and Extrahippocampal Subregions in Alzheimer's Disease at 3T and 7T: What Atlas Composition Works Best? %A Xie, Long %A Shinohara, Russell T %A Ittyerah, Ranjit %A Kuijf, Hugo J %A Pluta, John B %A Blom, Kim %A Kooistra, Minke %A Reijmer, Yael D %A Koek, Huiberdina L %A Zwanenburg, Jaco J M %A Wang, Hongzhi %A Luijten, Peter R %A Geerlings, Mirjam I %A Das, Sandhitsu R %A Biessels, Geert Jan %A Wolk, David A %A Yushkevich, Paul A %A Wisse, Laura E M %X

BACKGROUND: Multi-atlas segmentation, a popular technique implemented in the Automated Segmentation of Hippocampal Subfields (ASHS) software, utilizes multiple expert-labelled images ("atlases") to delineate medial temporal lobe substructures. This multi-atlas method is increasingly being employed in early Alzheimer's disease (AD) research, it is therefore becoming important to know how the construction of the atlas set in terms of proportions of controls and patients with mild cognitive impairment (MCI) and/or AD affects segmentation accuracy.

OBJECTIVE: To evaluate whether the proportion of controls in the training sets affects the segmentation accuracy of both controls and patients with MCI and/or early AD at 3T and 7T.

METHODS: We performed cross-validation experiments varying the proportion of control subjects in the training set, ranging from a patient-only to a control-only set. Segmentation accuracy of the test set was evaluated by the Dice similarity coeffiecient (DSC). A two-stage statistical analysis was applied to determine whether atlas composition is linked to segmentation accuracy in control subjects and patients, for 3T and 7T.

RESULTS: The different atlas compositions did not significantly affect segmentation accuracy at 3T and for patients at 7T. For controls at 7T, including more control subjects in the training set significantly improves the segmentation accuracy, but only marginally, with the maximum of 0.0003 DSC improvement per percent increment of control subject in the training set.

CONCLUSION: ASHS is robust in this study, and the results indicate that future studies investigating hippocampal subfields in early AD populations can be flexible in the selection of their atlas compositions.

%B J Alzheimers Dis %V 63 %P 217-225 %8 2018 %G eng %N 1 %1 http://www.ncbi.nlm.nih.gov/pubmed/29614654?dopt=Abstract %R 10.3233/JAD-170932 %0 Journal Article %J J Alzheimers Dis %D 2018 %T White Matter Hyperintensities and Cognition in Mild Cognitive Impairment and Alzheimer's Disease: A Domain-Specific Meta-Analysis. %A van den Berg, Esther %A Geerlings, Mirjam I %A Biessels, Geert Jan %A Nederkoorn, Paul J %A Kloppenborg, Raoul P %X

BACKGROUND: White matter hyperintensities (WMHs) are related to cognitive dysfunction in the general population. The clinical relevance of WMHs in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI) is, however, unclear.

OBJECTIVE: This meta-analysis aimed to quantify the association of WMHs and specific cognitive domains in patients with MCI or AD.

METHODS: PubMed (January 1990-January 2017) was searched for studies that used MRI to quantify WMHs, and measured cognitive functioning (≥1 predefined cognitive domain with ≥1 test) in a well-defined population of persons diagnosed with MCI or AD. Fischer's Z was used as the common metric for effect size. Modifying effects of demographics, MMSE, and WMH location were examined.

RESULTS: Twelve cross-sectional studies on AD (total n = 1,370, median age 75 years) and 10 studies on MCI (9 cross-sectional, 1 longitudinal; total n = 2,286, median age 73 years) were included. The association between WMHs and overall cognition was significantly stronger for MCI (-0.25, -0.36 to -0.14) than for AD (-0.11, -0.14 to -0.08; QM = 10.7, p < 0.05). For both groups, largest effect sizes were found in attention and executive functions (-0.26, -0.36 to -0.15) and processing speed (-0.21, -0.35 to -0.12). No significant modifying effects of age and gender were found.

CONCLUSION: WMHs have a medium-sized association with different cognitive functions in patients with MCI and a small, but statistically significant, association with cognition in AD. These result underscore the role of co-occurring vascular brain damage in MCI and AD.

%B J Alzheimers Dis %V 63 %P 515-527 %8 2018 %G eng %N 2 %1 http://www.ncbi.nlm.nih.gov/pubmed/29630548?dopt=Abstract %R 10.3233/JAD-170573 %0 Journal Article %J J Alzheimers Dis %D 2017 %T Abnormalities of Cerebral Deep Medullary Veins on 7 Tesla MRI in Amnestic Mild Cognitive Impairment and Early Alzheimer's Disease: A Pilot Study. %A Bouvy, Willem H %A Kuijf, Hugo J %A Zwanenburg, Jaco J M %A Koek, Huiberdina L %A Kappelle, L Jaap %A Luijten, Peter R %A Ikram, M Kamran %A Biessels, Geert Jan %K Aged %K Aged, 80 and over %K Alzheimer Disease %K Analysis of Variance %K Brain %K Cerebral Small Vessel Diseases %K Cognitive Dysfunction %K Female %K Humans %K Image Processing, Computer-Assisted %K Magnetic Resonance Imaging %K Male %X

Cerebral small vessel disease (SVD) contributes to cognitive impairment and dementia. SVD may affect veins, but veins are difficult to detect with 1.5 and 3T MRI. We compared deep medullary veins (DMVs) visualized on 7T-MRI between patients with early Alzheimer's disease (eAD; n = 17) or amnestic MCI (aMCI; n = 12) and controls (n = 40). The number and density of DMVs was similar in patients and controls, but tortuosity was higher in eAD (Cohen's d = 0.7, 95% CI: 0.1-1.2, p = 0.02) and aMCI (Cohen's d = 0.8, 95% CI: 0.2-1.5, p = 0.01), independent of brain atrophy. Venous changes provide a new perspective on vascular involvement in dementia.

%B J Alzheimers Dis %V 57 %P 705-710 %8 2017 %G eng %N 3 %1 http://www.ncbi.nlm.nih.gov/pubmed/28282806?dopt=Abstract %R 10.3233/JAD-160952 %0 Journal Article %J J Alzheimers Dis %D 2017 %T Cortical Cerebral Microinfarcts on 3 Tesla MRI in Patients with Vascular Cognitive Impairment. %A Ferro, Doeschka A %A van Veluw, Susanne J %A Koek, Huiberdina L %A Exalto, Lieza G %A Biessels, Geert Jan %X

BACKGROUND: Cerebral microinfarcts (CMIs) are small ischemic lesions that are a common neuropathological finding in patients with stroke or dementia. CMIs in the cortex can now be detected in vivo on 3 Tesla MRI.

OBJECTIVE: To determine the occurrence of CMIs and associated clinical features in patients with possible vascular cognitive impairment (VCI).

METHOD: 182 memory-clinic patients (mean age 71.4±10.6, 55% male) with vascular injury on brain MRI (i.e., possible VCI) underwent a standardized work-up including 3 Tesla MRI and cognitive assessment. A control group consisted of 70 cognitively normal subjects (mean age 70.6±4.7, 60% male). Cortical CMIs and other neuroimaging markers of vascular brain injury were rated according to established criteria.

RESULT: Occurrence of CMIs was higher (20%) in patients compared to controls (10%). Among patients, the presence of CMIs was associated with male sex, history of stroke, infarcts, and white matter hyperintensities. CMI presence was also associated with a diagnosis of vascular dementia and reduced performance in multiple cognitive domains.

CONCLUSION: CMIs on 3 Tesla MRI are common in patients with possible VCI and co-occur with imaging markers of small and large vessel disease, likely reflecting a heterogeneous etiology. CMIs are associated with worse cognitive performance, independent of other markers of vascular brain injury.

%B J Alzheimers Dis %V 60 %P 1443-1450 %8 2017 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/29036822?dopt=Abstract %R 10.3233/JAD-170481