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2. Next generation brain health: transforming global research and public health to promote prevention of dementia and reduce its risk in young adult populations

Author

Farina, Francesca R, Bridgeman, Katie, Gregory, Sarah, Crivelli, Lucía, Foote, Isabelle F, Jutila, Otto-Emil I, Kucikova, Ludmila, Mariano, Luciano I, Nguyen, Kim-Huong, Thayanandan, Tony, Akindejoye, Funmi, Butler, Joe, Calandri, Ismael L, Čepukaitytė, Giedrė, Chiesa, Scott T, Dawson, Walter D, Deckers, Kay, Cruz-Góngora, Vanessa De la, Dounavi, Maria-Eleni, Govia, Ishtar, Guzmán-Vélez, Edmarie, Heikal, Shimaa A, Hill-Jarrett, Tanisha G, Ibáñez, Agustín, James, Bryan D, McGlinchey, Eimear, Mullin, Donncha S, Muniz-Terrera, Graciela, Pintado Caipa, Maritza, Qansuwa, Esraa M, Robinson, Louise, Santuccione Chadha, Antonella, Shannon, Oliver M, Su, Li, Weidner, Wendy, and Booi, Laura

Published
2024
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4. Associations Between Retinal Microvasculature Changes and Gray Matter Volume in a Mid-Life Cohort at Risk of Developing Alzheimer’s Disease

Author

Rashid, Darwon, Giarratano, Ylenia, Hamid, Charlene, MacGillivray, Tom, Terrera, Graciela Muniz, Ritchie, Craig, Dhillon, Baljean, Reid-Schachter, Megan, Low, Audrey, Dounavi, Maria-Eleni, O’Brien, John T., Bernabeu, Miguel O., Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Antony, Bhavna, editor, Chen, Hao, editor, Fang, Huihui, editor, Fu, Huazhu, editor, Lee, Cecilia S., editor, and Zheng, Yalin, editor

Published
2023
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5. Associations Between Retinal Microvasculature Changes and Gray Matter Volume in a Mid-Life Cohort at Risk of Developing Alzheimer’s Disease

Author

Rashid, Darwon, primary, Giarratano, Ylenia, additional, Hamid, Charlene, additional, MacGillivray, Tom, additional, Terrera, Graciela Muniz, additional, Ritchie, Craig, additional, Dhillon, Baljean, additional, Reid-Schachter, Megan, additional, Low, Audrey, additional, Dounavi, Maria-Eleni, additional, O’Brien, John T., additional, and Bernabeu, Miguel O., additional

Published
2023
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9. The pivotal role of sleep in mediating the effects of life stressors and healthy habits on allostatic load in mid-life adults.

Author

Buller-Peralta, Ingrid, Gregory, Sarah, Low, Audrey, Dounavi, Maria-Eleni, Bridgeman, Katie, Ntailianis, Georgios, Lawlor, Brian, Naci, Lorina, Koychev, Ivan, Malhotra, Paresh, O'Brien, John T., Ritchie, Craig W., Dauvilliers, Yves, and Muniz-Terrera, Graciela

Subjects
SLEEP quality, SUBJECTIVE stress, STRUCTURAL equation modeling, COGNITIVE load, MIDDLE age
Abstract

Objectives: We assessed the modulation of allostatic load (AL) by engagement in healthy habits and life stressors, mediated through resilience and the perceived influence of the stressors. Sleep was included as third mediator given extensive evidence associating to all the analysed factors. Methods: Structural equation models to assess the modulation of AL by either traumatic or psychosocial stressors and healthy habits were generated with data from 620 mid-life adults (age 51.3 ± 5.48 years). Model 1 included self-reported life stressors, engagement in cognitive and physical activities, resilience and a pyramid score for diet. In Model 2, self-reported sleep quality was included in the mediation analysis between resilience and perceived stress on AL. Results: Direct effects of sports and diet on AL, and on resilience by sports were found in all the evaluated models. The modulation of AL by both types of stressors was only revealed in model 2, through indirect effects of perceived influence via sleep quality. An effect of sport habits on AL via resilience was found to be mediated by sleep, and equivalent but opposed effects of perceived influence of stressors and resilience on sleep quality emerged as critical factor for AL modulation. Conclusion: Our results suggest that sleep plays a pivotal role in the modulation of AL by both life stressors and sport habits, balancing the harmful and protective effects of perceived stress and resilience. The relative weight of one over the other to worsen or improve sleep quality will determine the resulting level of AL. [ABSTRACT FROM AUTHOR]

Published
2025
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10. Modifiable and non-modifiable risk factors of dementia on midlife cerebral small vessel disease in cognitively healthy middle-aged adults: the PREVENT-Dementia study

Author

Low, Audrey, Prats-Sedano, Maria A., McKiernan, Elizabeth, Carter, Stephen F., Stefaniak, James D., Nannoni, Stefania, Su, Li, Dounavi, Maria-Eleni, Muniz-Terrera, Graciela, Ritchie, Karen, Lawlor, Brian, Naci, Lorina, Malhotra, Paresh, Mackay, Clare, Koychev, Ivan, Ritchie, Craig W., Markus, Hugh S., and O’Brien, John T.

Published
2022
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11. An insight into the brain of patients with type-2 diabetes mellitus and impaired glucose tolerance using multi-modal magnetic resonance image processing

Author

Dounavi, Maria Eleni, Wilkinson, Iain D., Martin, Christopher, and Armitage, Paul

Subjects
610
Abstract

The purpose of this thesis was to investigate brain anatomy and physiology of subjects with impaired glucose tolerance (IGT - 12 subjects), type-2 diabetes (T2DM - 17 subjects) and normoglycemia (16 subjects) using multi-modal magnetic resonance imaging (MRI) at 3T. Perfusion imaging using quantitative STAR labeling of arterial regions (QUASAR) arterial spin labeling (ASL) was the core dataset. Optimization of the post-processing methodology for this sequence was performed and the outcome was used for hemodynamic analysis of the cohort. Typical perfusion-related parameters, along with novel hemodynamic features were quantified. High-resolution structural, angiographic and carotid flow scans were also acquired and processed. Functional acquisitions were repeated following a vasodilating stimulus. Differences between the groups were examined using statistical analysis and a machine-learning framework. Hemodynamic parameters differing between the groups emerged from both baseline and post-stimulus scans for T2DM and mainly from the post-stimulus scan for IGT. It was demonstrated that quantification of not-typically determined hemodynamic features could lead to optimal group-separation. Such features captured the pattern of delayed delivery of the blood to the arterial and tissue compartments of the hyperglycemic groups. Alterations in gray and white matter, cerebral vasculature and carotid blood flow were detected for the T2DM group. The IGT cohort was structurally similar to the healthy cohort but demonstrated functional similarities to T2DM. When combining all extracted MRI metrics, features driving optimal separation between different glycemic conditions emerged mainly from the QUASAR scan. The only highly discriminant non-QUASAR feature, when comparing T2DM to healthy subjects, emerged from the cerebral angiogram. In this thesis, it was demonstrated that MRI-derived features could lead to potentially optimal differentiation between normoglycemia and hyperglycemia. More importantly, it was shown that an impaired cerebral hemodynamic pattern exists in both IGT and T2DM and that the IGT group exhibits functional alterations similar to the T2DM group.

Published
2018

16. The Mediterranean diet is not associated with neuroimaging or cognition in middle‐aged adults: a cross‐sectional analysis of the PREVENT dementia programme

Author

Gregory, Sarah, primary, Buller‐Peralta, Ingrid, additional, Bridgeman, Katie, additional, Góngora, Vanessa De La Cruz, additional, Dounavi, Maria‐Eleni, additional, Low, Audrey, additional, Ntailianis, Georgios, additional, O'Brien, John, additional, Parra, Mario A., additional, Ritchie, Craig W., additional, Ritchie, Karen, additional, Shannon, Oliver M., additional, Stevenson, Emma J., additional, and Muniz‐Terrera, Graciela, additional

Published
2024
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17. Investigating the brain’s neurochemical profile at midlife in relation to dementia risk factors

Author

Dounavi, Maria-Eleni, primary, McKiernan, Elizabeth, additional, Langsen, Michael, additional, Gregory, Sarah, additional, Muniz-Terrera, Graciela, additional, Prats-Sedano, Maria Angeles, additional, Mada, Marius Ovidiu, additional, Williams, Guy B, additional, Lawlor, Brian, additional, Naci, Lorina, additional, Mackay, Clare, additional, Koychev, Ivan, additional, Malhotra, Paresh, additional, Ritchie, Karen, additional, Ritchie, Craig W, additional, Su, Li, additional, Waldman, Adam D, additional, and O’ Brien, John T, additional

Published
2024
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18. Reproducibility of arterial spin labeling cerebral blood flow image processing: A report of the ISMRM open science initiative for perfusion imaging (OSIPI)_and the ASL MRI challenge

Author

Paschoal, Andre M., primary, Woods, Joseph G., additional, Pinto, Joana, additional, Bron, Esther E., additional, Petr, Jan, additional, Kennedy McConnell, Flora A., additional, Bell, Laura, additional, Dounavi, Maria‐Eleni, additional, van Praag, Cassandra Gould, additional, Mutsaerts, Henk J. M. M., additional, Taylor, Aaron Oliver, additional, Zhao, Moss Y., additional, Brumer, Irène, additional, Chan, Wei Siang Marcus, additional, Toner, Jack, additional, Hu, Jian, additional, Zhang, Logan X., additional, Domingos, Catarina, additional, Monteiro, Sara P., additional, Figueiredo, Patrícia, additional, Harms, Alexander G. J., additional, Padrela, Beatriz E., additional, Tham, Channelle, additional, Abdalle, Ahmed, additional, Croal, Paula L., additional, and Anazodo, Udunna, additional

Published
2024
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20. Reproducibility of arterial spin labeling cerebral blood flow image processing:A report of the ISMRM open science initiative for perfusion imaging (OSIPI) and the ASL MRI challenge

Author

Paschoal, Andre M., Woods, Joseph G., Pinto, Joana, Bron, Esther E., Petr, Jan, Kennedy McConnell, Flora A., Bell, Laura, Dounavi, Maria Eleni, van Praag, Cassandra Gould, Mutsaerts, Henk J.M.M., Taylor, Aaron Oliver, Zhao, Moss Y., Brumer, Irène, Chan, Wei Siang Marcus, Toner, Jack, Hu, Jian, Zhang, Logan X., Domingos, Catarina, Monteiro, Sara P., Figueiredo, Patrícia, Harms, Alexander G.J., Padrela, Beatriz E., Tham, Channelle, Abdalle, Ahmed, Croal, Paula L., Anazodo, Udunna, Paschoal, Andre M., Woods, Joseph G., Pinto, Joana, Bron, Esther E., Petr, Jan, Kennedy McConnell, Flora A., Bell, Laura, Dounavi, Maria Eleni, van Praag, Cassandra Gould, Mutsaerts, Henk J.M.M., Taylor, Aaron Oliver, Zhao, Moss Y., Brumer, Irène, Chan, Wei Siang Marcus, Toner, Jack, Hu, Jian, Zhang, Logan X., Domingos, Catarina, Monteiro, Sara P., Figueiredo, Patrícia, Harms, Alexander G.J., Padrela, Beatriz E., Tham, Channelle, Abdalle, Ahmed, Croal, Paula L., and Anazodo, Udunna

Abstract

Purpose: Arterial spin labeling (ASL) is a widely used contrast-free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM-OSIPI ASL-MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. Methods: Eight teams analyzed the challenge data, which included a high-resolution T1-weighted anatomical image and 10 pseudo-continuous ASL datasets simulated using a digital reference object to generate ground-truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra-class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. Results: Absolute errors in CBF estimates compared to ground-truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground-truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. Conclusions: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top-performing approaches as a step toward ASL standardization.

Published
2024

22. Texture‐based morphometry in relation to apolipoprotein ε4 genotype, ageing and sex in a midlife population.

Author

Dounavi, Maria‐Eleni, Mak, Elijah, Operto, Gregory, Muniz‐Terrera, Graciela, Bridgeman, Katie, Koychev, Ivan, Malhotra, Paresh, Naci, Lorina, Lawlor, Brian, Su, Li, Falcon, Carles, Ritchie, Karen, Ritchie, Craig W., Gispert, Juan Domingo, and O'Brien, John T.

Subjects
*OLDER people, *ALZHEIMER'S disease, *APOLIPOPROTEIN E4, *CEREBRAL cortical thinning, *DISEASE risk factors
Abstract

Brain atrophy and cortical thinning are typically observed in people with Alzheimer's disease (AD) and, to a lesser extent, in those with mild cognitive impairment. In asymptomatic middle‐aged apolipoprotein ε4 (ΑPOE4) carriers, who are at higher risk of future AD, study reports are discordant with limited evidence of brain structural differences between carriers and non‐carriers of the ε4 allele. Alternative imaging markers with higher sensitivity at the presymptomatic stage, ideally quantified using typically acquired structural MRI scans, would thus be of great benefit for the detection of early disease, disease monitoring and subject stratification. In the present cross‐sectional study, we investigated textural properties of T1‐weighted 3T MRI scans in relation to APOE4 genotype, age and sex. We pooled together data from the PREVENT‐Dementia and ALFA studies focused on midlife healthy populations with dementia risk factors (analysable cohort: 1585 participants; mean age 56.2 ± 7.4 years). Voxel‐based and texture (examined features: contrast, entropy, energy, homogeneity) based morphometry was used to identify areas of volumetric and textural differences between APOE4 carriers and non‐carriers. Textural maps were generated and were subsequently harmonised using voxel‐wise COMBAT. For all analyses, APOE4, sex, age and years of education were used as model predictors. Interactions between APOE4 and age were further examined. There were no group differences in regional brain volume or texture based on APOE4 carriership or when age × APOE4 interactions were examined. Older people tended to have a less homogeneous textural profile in grey and white matter and a more homogeneous profile in the ventricles. A more heterogeneous textural profile was observed for females in areas such as the ventricles, frontal and parietal lobes and for males in the brainstem, cerebellum, precuneus and cingulate. Overall, we have shown the absence of volumetric and textural differences between APOE4 carriers and non‐carriers at midlife and have established associations of textural features with ageing and sex. [ABSTRACT FROM AUTHOR]

Published
2024
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23. Reproducibility of arterial spin labeling cerebral blood flow image processing: A report of the ISMRM open science initiative for perfusion imaging (OSIPI) and the ASL MRI challenge.

Author

Paschoal, Andre M., Woods, Joseph G., Pinto, Joana, Bron, Esther E., Petr, Jan, Kennedy McConnell, Flora A., Bell, Laura, Dounavi, Maria‐Eleni, van Praag, Cassandra Gould, Mutsaerts, Henk J. M. M., Taylor, Aaron Oliver, Zhao, Moss Y., Brumer, Irène, Chan, Wei Siang Marcus, Toner, Jack, Hu, Jian, Zhang, Logan X., Domingos, Catarina, Monteiro, Sara P., and Figueiredo, Patrícia

Subjects
CEREBRAL circulation, PERFUSION imaging, SPIN labels, IMAGE processing, OPEN scholarship
Abstract

Purpose: Arterial spin labeling (ASL) is a widely used contrast‐free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM‐OSIPI ASL‐MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. Methods: Eight teams analyzed the challenge data, which included a high‐resolution T1‐weighted anatomical image and 10 pseudo‐continuous ASL datasets simulated using a digital reference object to generate ground‐truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra‐class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. Results: Absolute errors in CBF estimates compared to ground‐truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground‐truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. Conclusions: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top‐performing approaches as a step toward ASL standardization. [ABSTRACT FROM AUTHOR]

Published
2024
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24. Brain age gap, dementia risk factors and cognition in middle age

Author

Stefaniak, James D, primary, Mak, Elijah, additional, Su, Li, additional, Carter, Stephen F, additional, Dounavi, Maria‐Eleni, additional, Muniz‐Terrera, Graciela, additional, Wells, Katie, additional, Ritchie, Karen, additional, Lawlor, Brian, additional, Naci, Lorina, additional, Koychev, Ivan, additional, Malhotra, Paresh A, additional, Ritchie, Craig W, additional, and O'Brien, John T, additional

Published
2023
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25. Lifestyle activities contribute to cognitive reserve in mid‐life, independently of education, in cognitively healthy middle‐aged individuals at risk for late‐life Alzheimer’s disease

Author

Deng, Feng, primary, El‐Sherbiny, Sandra, additional, Heneghan, Amy, additional, Dounavi, Maria‐Eleni, additional, Ritchie, Karen, additional, Muniz‐Terrera, Graciela, additional, Malhotra, Paresh A, additional, Ritchie, Craig W, additional, Lawlor, Brian, additional, and Naci, Lorina, additional

Published
2023
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26. Investigating the impact of APOE4 genotype on the association between cerebral blood flow and haematological properties in mid‐life adults

Author

Dounavi, Maria‐Eleni, primary, Mak, Elijah, additional, Low, Audrey, additional, Williams, Guy B, additional, Wells, Katie, additional, Muniz‐Terrera, Graciela, additional, Lawlor, Brian A, additional, Naci, Lorina, additional, Malhotra, Paresh A, additional, Koychev, Ivan, additional, Ritchie, Karen, additional, Su, Li, additional, Ritchie, Craig W, additional, and O'Brien, John T, additional

Published
2023
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28. Apoe ε4 exacerbates age‐dependent decline of cortical microstructural changes in cognitively normal midlife individuals: the PREVENT‐Dementia and ALFA studies

Author

Mak, Elijah, primary, Dounavi, Maria‐Eleni, additional, Operto, Grégory, additional, Ziukelis, Elina T, additional, Jones, P Simon, additional, Low, Audrey, additional, Swann, Peter, additional, Newton, Coco, additional, Muniz‐Terrera, Graciela, additional, Malhotra, Paresh A, additional, Koychev, Ivan, additional, Falcon, Carles, additional, Mackay, Clare, additional, Lawlor, Brian, additional, Naci, Lorina, additional, Wells, Katie, additional, Ritchie, Craig W, additional, Ritchie, Karen, additional, Su, Li, additional, Gispert, Juan Domingo, additional, and O'Brien, John T, additional

Published
2023
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29. Dietary patterns, cardiometabolic and brain health in the PREVENT Dementia Cohort

Author

Gregory, Sarah, primary, Dounavi, Maria‐Eleni, additional, Low, Audrey, additional, Ntailianis, Georgios, additional, O'Brien, John T, additional, Parra‐Rodriguez, Mario A, additional, Shannon, Oliver M, additional, Stevenson, Emma, additional, Ritchie, Craig W, additional, Ritchie, Karen, additional, Wells, Katie, additional, and Muniz‐Terrera, Graciela, additional

Published
2023
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30. Cerebral microbleeds in traumatic brain injury associated with differential risk factors and clinical outcomes: the PREVENT‐Dementia study

Author

Low, Audrey, primary, McKiernan, Elizabeth, additional, Prats‐Sedano, Maria A, additional, Carter, Stephen F, additional, Stefaniak, James D, additional, Su, Li, additional, Dounavi, Maria‐Eleni, additional, Muniz‐Terrera, Graciela, additional, Jenkins, Natalie D, additional, Ritchie, Karen, additional, Lawlor, Brian, additional, Naci, Lorina, additional, Malhotra, Paresh A, additional, Thayanandan, Tony, additional, Mackay, Clare, additional, Koychev, Ivan, additional, Raymont, Vanessa, additional, Ritchie, Craig W, additional, and O'Brien, John T, additional

Published
2023
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31. Family history of dementia is associated with longer sleep duration and smaller volume of the thalamus in the PREVENT‐Dementia study

Author

Laurell, Axel AS, primary, Shah, Sita, additional, Dounavi, Maria‐Eleni, additional, Dudas, Robert B, additional, Dauvilliers, Yves, additional, Ritchie, Craig W, additional, Koychev, Ivan, additional, Lawlor, Brian A, additional, Naci, Lorina, additional, Malhotra, Paresh A, additional, and O'Brien, John T, additional

Published
2023
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33. Comprehensive allostatic load risk index is associated with increased frontal and left parietal white matter hyperintensities in mid-life cognitively healthy adults

Author

Buller-Peralta, Ingrid, primary, Gregory, Sarah, additional, Low, Audrey, additional, Dounavi, Maria-Eleni, additional, Wells, Katie, additional, Ntailianis, Georgios, additional, Lawlor, Brian, additional, Naci, Lorina, additional, Koychev, Ivan, additional, Malhotra, Paresh, additional, O'Brien, John T, additional, Ritchie, Craig W, additional, and Terrera, Graciela Muniz, additional

Published
2023
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34. The PREVENT dementia programme: baseline demographic, lifestyle, imaging and cognitive data from a midlife cohort study investigating risk factors for dementia.

Author

Ritchie, Craig W, Bridgeman, Katie, Gregory, Sarah, O'Brien, John T, Danso, Samuel O, Dounavi, Maria-Eleni, Carriere, Isabelle, Driscoll, David, Hillary, Robert, Koychev, Ivan, Lawlor, Brian, Naci, Lorina, Su, Li, Low, Audrey, Mak, Elijah, Malhotra, Paresh, Manson, Jean, Marioni, Riccardo, Murphy, Lee, and Ntailianis, Georgios

Published
2024
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35. Entorhinal‐based path integration selectively predicts midlife risk of Alzheimer's disease.

Author

Newton, Coco, Pope, Marianna, Rua, Catarina, Henson, Richard, Ji, Zilong, Burgess, Neil, Rodgers, Christopher T., Stangl, Matthias, Dounavi, Maria‐Eleni, Castegnaro, Andrea, Koychev, Ivan, Malhotra, Paresh, Wolbers, Thomas, Ritchie, Karen, Ritchie, Craig W., O'Brien, John, Su, Li, and Chan, Dennis

Abstract

INTRODUCTION: Entorhinal cortex (EC) is the first cortical region to exhibit neurodegeneration in Alzheimer's disease (AD), associated with EC grid cell dysfunction. Given the role of grid cells in path integration (PI)–based spatial behaviors, we predicted that PI impairment would represent the first behavioral change in adults at risk of AD. METHODS: We compared immersive virtual reality (VR) PI ability to other cognitive domains in 100 asymptomatic midlife adults stratified by hereditary and physiological AD risk factors. In some participants, behavioral data were compared to 7T magnetic resonance imaging (MRI) measures of brain structure and function. RESULTS: Midlife PI impairments predicted both hereditary and physiological AD risk, with no corresponding multi‐risk impairment in episodic memory or other spatial behaviors. Impairments associated with altered functional MRI signal in the posterior‐medial EC. DISCUSSION: Altered PI may represent the transition point from at‐risk state to disease manifestation in AD, prior to impairment in other cognitive domains. [ABSTRACT FROM AUTHOR]

Published
2024
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36. The PREVENT Dementia programme: Baseline demographic, lifestyle, imaging and cognitive data from a midlife cohort study investigating risk factors for dementia

Author

Ritchie, Craig W., primary, Wells, Katie, additional, Gregory, Sarah, additional, Carriere, Isabelle, additional, Danso, Samuel O., additional, Driscoll, David, additional, Dounavi, Maria-Eleni, additional, Hillary, Robert, additional, Koychev, Ivan, additional, Lawlor, Brian, additional, Li, Su, additional, Low, Audrey, additional, Mak, Elijah, additional, Malhotra, Paresh, additional, Manson, Jean, additional, Marioni, Riccardo, additional, Murphy, Lee, additional, Naci, Lorina, additional, O’Brien, John T, additional, Stewart, William, additional, Muniz-Terrera, Graciela, additional, and Ritchie, Karen, additional

Published
2023
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37. Lifestyle activities in mid-life contribute to cognitive reserve in middle-aged individuals at risk for late-life Alzheimer’s disease, independent of education and occupation

Author

Deng, Feng, primary, El-Sherbiny, Sandra, additional, Dounavi, Maria-Eleni, additional, Ritchie, Karen, additional, Muniz-Terrera, Graciela, additional, Malhotra, Paresh, additional, Ritchie, Craig W, additional, Lawlor, Brian, additional, and Naci, Lorina, additional

Published
2023
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39. APOE ɛ4 exacerbates age-dependent deficits in cortical microstructure.

Author

Mak, Elijah, Dounavi, Maria-Eleni, Operto, Grégory, Ziukelis, Elina T, Jones, Peter Simon, Low, Audrey, Swann, Peter, Newton, Coco, Terrera, Graciela Muniz, Malhotra, Paresh, Koychev, Ivan, Falcon, Carles, Mackay, Clare, Lawlor, Brian, Naci, Lorina, Wells, Katie, Ritchie, Craig, Ritchie, Karen, Su, Li, and Gispert, Juan Domingo

Published
2024
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40. Path integration selectively predicts midlife risk of Alzheimer’s disease

Author

Newton, Coco, Pope, Marianna, Rua, Catarina, Henson, Richard, Ji, Zilong, Burgess, Neil, Rodgers, Christopher T., Stangl, Matthias, Dounavi, Maria-Eleni, Castegnaro, Andrea, Koychev, Ivan, Malhotra, Paresh, Wolbers, Thomas, Ritchie, Karen, Ritchie, Craig W., O’Brien, John, Su, Li, and Chan, Dennis

Subjects
Article
Abstract

The entorhinal cortex (EC) is the first cortical region to exhibit neurodegeneration in Alzheimer’s disease (AD), associated with EC grid cell dysfunction. Given the role of grid cells in path integration, we predicted that path integration impairment would represent the first behavioural change in adults at-risk of AD. Using immersive virtual reality, we found that midlife path integration impairments predicted both hereditary and physiological AD risk, with no corresponding impairment on tests of episodic memory or other spatial behaviours.Impairments related to poorer angular estimation and were associated with hexadirectional grid-like fMRI signal in the posterior-medial EC. These results indicate that altered path integration may represent the transition point from at-risk state to disease onset in AD, prior to impairment in other cognitive domains.

Published
2023
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41. sj-pdf-1-jcb-10.1177_0271678X231173587 - Supplemental material for Differential association of cerebral blood flow and anisocytosis in APOE ε4 carriers at midlife

Author

Dounavi, Maria-Eleni, Mak, Elijah, Swann, Peter, Low, Audrey, Muniz-Terrera, Graciela, McKeever, Anna, Pope, Marianna, Williams, Guy B, Wells, Katie, Lawlor, Brian, Naci, Lorina, Malhotra, Paresh, Mackay, Clare, Koychev, Ivan, Ritchie, Karen, Su, Li, Ritchie, Craig W, and O’Brien, John T

Subjects
110320 Radiology and Organ Imaging, FOS: Clinical medicine, FOS: Biological sciences, Medicine, Cell Biology, 110305 Emergency Medicine, 110306 Endocrinology, Biochemistry, 69999 Biological Sciences not elsewhere classified, 110904 Neurology and Neuromuscular Diseases, Neuroscience
Abstract

Supplemental material, sj-pdf-1-jcb-10.1177_0271678X231173587 for Differential association of cerebral blood flow and anisocytosis in APOE ε4 carriers at midlife by Maria-Eleni Dounavi, Elijah Mak, Peter Swann, Audrey Low, Graciela Muniz-Terrera, Anna McKeever, Marianna Pope, Guy B Williams, Katie Wells, Brian Lawlor, Lorina Naci, Paresh Malhotra, Clare Mackay, Ivan Koychev, Karen Ritchie, Li Su, Craig W Ritchie and John T O’Brien: on behalf of the SVDs@target consortium in Journal of Cerebral Blood Flow & Metabolism

Published
2023
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42. Path integration selectively predicts midlife risk of Alzheimer's disease

Author

Newton, Coco, primary, Pope, Marianna, additional, Rua, Catarina, additional, Henson, Richard, additional, Ji, Zilong, additional, Burgess, Neil, additional, Rodgers, Christopher T, additional, Stangl, Matthias, additional, Dounavi, Maria-Eleni, additional, Castegnaro, Andrea, additional, Koychev, Ivan, additional, Malhotra, Paresh, additional, Wolbers, Thomas, additional, Ritchie, Karen, additional, Ritchie, Craig, additional, O'Brien, John, additional, Su, Li, additional, and Chan, Dennis, additional

Published
2023
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43. Multifactor mid‐life risk for Alzheimer’s disease associated with alterations in navigation but not episodic memory: the PREVENT‐Dementia study

Author

Newton, Coco, primary, Pope, Marianna, additional, Dounavi, Maria‐Eleni, additional, Carter, Stephen F, additional, Muniz‐Terrera, Graciela, additional, Henson, Richard N, additional, Ritchie, Karen, additional, Ritchie, Craig W., additional, O'Brien, John T, additional, Su, Li, additional, and Chan, Dennis, additional

Published
2022
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45. Fractal dimension of the brain in neurodegenerative disease and dementia: A systematic review

Author

Ziukelis, Elina T, Mak, Elijah, Dounavi, Maria-Eleni, Su, Li, T O'Brien, John, Mak, Elijah [0000-0002-6437-8024], and Apollo - University of Cambridge Repository

Subjects
Aging, Cortical complexity, Brain, Neurodegenerative Diseases, Biochemistry, Cognitive impairment, Magnetic resonance imaging, Fractals, Neurology, Alzheimer Disease, Humans, Dementia, Neurodegeneration, Atrophy, Fractal dimension, Molecular Biology, Biotechnology
Abstract

Sensitive and specific antemortem biomarkers of neurodegenerative disease and dementia are crucial to the pursuit of effective treatments, required both to reliably identify disease and to track its progression. Atrophy is the structural magnetic resonance imaging (MRI) hallmark of neurodegeneration. However in most cases it likely indicates a relatively advanced stage of disease less susceptible to treatment as some disease processes begin decades prior to clinical onset. Among emerging metrics that characterise brain shape rather than volume, fractal dimension (FD) quantifies shape complexity. FD has been applied in diverse fields of science to measure subtle changes in elaborate structures. We review its application thus far to structural MRI of the brain in neurodegenerative disease and dementia. We identified studies involving subjects who met criteria for mild cognitive impairment, Alzheimer's Disease, Vascular Dementia, Lewy Body Dementia, Frontotemporal Dementia, Amyotrophic Lateral Sclerosis, Parkinson's Disease, Huntington's Disease, Multiple Systems Atrophy, Spinocerebellar Ataxia and Multiple Sclerosis. The early literature suggests that neurodegenerative disease processes are usually associated with a decline in FD of the brain. The literature includes examples of disease-related change in FD occurring independently of atrophy, which if substantiated would represent a valuable advantage over other structural imaging metrics. However, it is likely to be non-specific and to exhibit complex spatial and temporal patterns. A more harmonious methodological approach across a larger number of studies as well as careful attention to technical factors associated with image processing and FD measurement will help to better elucidate the metric's utility.

Published
2022
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46. Additional file 1 of Modifiable and non-modifiable risk factors of dementia on midlife cerebral small vessel disease in cognitively healthy middle-aged adults: the PREVENT-Dementia study

Author

Low, Audrey, Prats-Sedano, Maria A., McKiernan, Elizabeth, Carter, Stephen F., Stefaniak, James D., Nannoni, Stefania, Su, Li, Dounavi, Maria-Eleni, Muniz-Terrera, Graciela, Ritchie, Karen, Lawlor, Brian, Naci, Lorina, Malhotra, Paresh, Mackay, Clare, Koychev, Ivan, Ritchie, Craig W., Markus, Hugh S., and O’Brien, John T.

Abstract

Additional file 1: Supplementary Table 1. Scoring of global cerebral small vessel disease (SVD) burden, hypertensive arteriopathy, and cerebral amyloid angiopathy scores. Supplementary Table 2. Factor loadings from confirmatory factor analysis of measurement models.

Published
2022
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47. The effects of age and hypertension on cerebral small‐vessel disease differ between men and women at midlife: The PREVENT Dementia study

Author

Low, Audrey, primary, Prats‐Sedano, Maria, additional, Stefaniak, James D, additional, Dounavi, Maria‐Eleni, additional, McKiernan, Elizabeth, additional, Carter, Stephen F, additional, Mak, Elijah, additional, Su, Li, additional, Muñiz‐Terrera, Graciela, additional, Ritchie, Karen, additional, Ritchie, Craig W, additional, Markus, Hugh S, additional, and O'Brien, John T, additional

Published
2021
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49. sj-pdf-1-jcb-10.1177_0271678X211020863 - Supplemental material for Evidence of cerebral hemodynamic dysregulation in middle-aged APOE ε4 carriers: The PREVENT-Dementia study

Author

Dounavi, Maria-Eleni, Low, Audrey, McKiernan, Elizabeth F, Mak, Elijah, Muniz-Terrera, Graciela, Ritchie, Karen, Ritchie, Craig W, Su, Li, and O’Brien, John T.

Subjects
110320 Radiology and Organ Imaging, FOS: Clinical medicine, FOS: Biological sciences, Medicine, Cell Biology, 110305 Emergency Medicine, 110306 Endocrinology, Biochemistry, 69999 Biological Sciences not elsewhere classified, 110904 Neurology and Neuromuscular Diseases, Neuroscience
Abstract

Supplemental material, sj-pdf-1-jcb-10.1177_0271678X211020863 for Evidence of cerebral hemodynamic dysregulation in middle-aged APOE ε4 carriers: The PREVENT-Dementia study by Maria-Eleni Dounavi, Audrey Low, Elizabeth F McKiernan, Elijah Mak, Graciela Muniz-Terrera, Karen Ritchie, Craig W Ritchie, Li Su and John T. O’Brien in Journal of Cerebral Blood Flow & Metabolism

Published
2021
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