Beta to theta power ratio in EEG periodic components as a potential biomarker in mild cognitive impairment and Alzheimer's dementia.

"Declarations Ethics approval and consent to participateAll research procedures involving human subjects were done in accord with the ethical standards of the Helsinki Declaration of 1975, and under a protocol approved by our hospital’s Institutional Review Board (CAMH: The Centre for Addiction and Mental Health, Toronto, ON, CA). All participants provided written informed consent as approved by the local Research Ethics Board and Clinical Trials Ontario. Consent for publicationNot applicable. Competing interestsAJF has received grant support from the US National Institutes of Health, the Patient-Centered Outcomes Research Institute, the Canadian Institutes of Health Research, Brain Canada, the Ontario Brain Institute, the Alzheimer’s Association, AGE-WELL, the Canadian Foundation for Healthcare Improvement, and the University of Toronto. BHM holds and receives support from the Labatt Family Chair in Biology of Depression in Late-Life Adults at the University of Toronto. He currently receives research support from Brain Canada, the Canadian Institutes of Health Research, the CAMH Foundation, the Patient-Centered Outcomes Research Institute (PCORI), the US National Institute of Health (NIH), Capital Solution Design LLC (software used in a study funded by CAMH Foundation), and HAPPYneuron (software used in a study funded by Brain Canada). Within the past five years, he has also received research support from Eli Lilly (medications for an NIH-funded clinical trial) and Pfizer (medications for an NIH-funded clinical trial). He has been an unpaid consultant to Myriad Neuroscience. BGP receives research support from the Peter & Shelagh Godsoe Endowed Chair in Late-Life Mental Health, CAMH Foundation and Discovery Fund, National Institute of Aging, Brain Canada, the Canadian Institutes of Health Research, the Alzheimer’s Drug Discovery Foundation, the Ontario Brain Institute, the Centre for Aging and Brain Health Innovation, the Bright Focus Foundation, the Alzheimer’s Society of Canada, the W. Garfield Weston Foundation, the Weston Brain Institute, the Canadian Consortium on Neurodegeneration in Aging and Genome Canada. BGP receives honoraria from the American Geriatrics Society and holds United States Provisional Patent No. 16/490,680 and Canadian Provisional Patent No. 3,054,093 for a cell-based assay and kits for assessing serum anticholinergic activity. CEF receives grant funding from the following sources: Vielight Inc, Hoffman La Roche, Novo-Nordisk, CIHR-CCNA, Mitochondrial Innovation Initiative, NIH, Brian Canada, the Weston Foundation, St. Michaels Hospital Foundation Heather and Eric Donnelly Endowment. CRB has received grant support from Pfizer, Lundbeck, and Takeda in the past 5 years. DMB has received research support from CIHR, NIH, Brain Canada and the Temerty Family through the CAMH Foundation and the Campbell Family Research Institute. He received research support and in-kind equipment support for an investigator-initiated study from Brainsway Ltd. He is the site principal investigator for three sponsor-initiated studies for Brainsway Ltd. He also receives in-kind equipment support from Magventure for two investigator-initiated studies. He received medication supplies for an investigator-initiated trial from Indivior. LM has received research funding from the Alzheimer’s Society of Canada, Centre for Aging and Brain Health Innovation, Ontario Ministry of Health and Long-Term Care, and Brainsway, Ltd. TKR has received research support from Brain Canada, Brain and Behavior Research Foundation, BrightFocus Foundation, Canada Foundation for Innovation, Canada Research Chair, Canadian Institutes of Health Research, Centre for Aging and Brain Health Innovation, National Institutes of Health, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research and Innovation, and the Weston Brain Institute. TKR also received in-kind equipment support for an investigator-initiated study from Magstim, and in-kind research accounts from Scientific Brain Training Pro. TKR participated in 2021 and 2022 in an advisory board for Biogen Canada Inc. HA, CZ, HB, RZ, NH, SK, and KL report no competing interests. Competing interests AJF has received grant support from the US National Institutes of Health, the Patient-Centered Outcomes Research Institute, the Canadian Institutes of Health Research, Brain Canada, the Ontario Brain Institute, the Alzheimer’s Association, AGE-WELL, the Canadian Foundation for Healthcare Improvement, and the University of Toronto. BHM holds and receives support from the Labatt Family Chair in Biology of Depression in Late-Life Adults at the University of Toronto. He currently receives research support from Brain Canada, the Canadian Institutes of Health Research, the CAMH Foundation, the Patient-Centered Outcomes Research Institute (PCORI), the US National Institute of Health (NIH), Capital Solution Design LLC (software used in a study funded by CAMH Foundation), and HAPPYneuron (software used in a study funded by Brain Canada). Within the past five years, he has also received research support from Eli Lilly (medications for an NIH-funded clinical trial) and Pfizer (medications for an NIH-funded clinical trial). He has been an unpaid consultant to Myriad Neuroscience. BGP receives research support from the Peter & Shelagh Godsoe Endowed Chair in Late-Life Mental Health, CAMH Foundation and Discovery Fund, National Institute of Aging, Brain Canada, the Canadian Institutes of Health Research, the Alzheimer’s Drug Discovery Foundation, the Ontario Brain Institute, the Centre for Aging and Brain Health Innovation, the Bright Focus Foundation, the Alzheimer’s Society of Canada, the W. Garfield Weston Foundation, the Weston Brain Institute, the Canadian Consortium on Neurodegeneration in Aging and Genome Canada. BGP receives honoraria from the American Geriatrics Society and holds United States Provisional Patent No. 16/490,680 and Canadian Provisional Patent No. 3,054,093 for a cell-based assay and kits for assessing serum anticholinergic activity. CEF receives grant funding from the following sources: Vielight Inc, Hoffman La Roche, Novo-Nordisk, CIHR-CCNA, Mitochondrial Innovation Initiative, NIH, Brian Canada, the Weston Foundation, St. Michaels Hospital Foundation Heather and Eric Donnelly Endowment. CRB has received grant support from Pfizer, Lundbeck, and Takeda in the past 5 years. DMB has received research support from CIHR, NIH, Brain Canada and the Temerty Family through the CAMH Foundation and the Campbell Family Research Institute. He received research support and in-kind equipment support for an investigator-initiated study from Brainsway Ltd. He is the site principal investigator for three sponsor-initiated studies for Brainsway Ltd. He also receives in-kind equipment support from Magventure for two investigator-initiated studies. He received medication supplies for an investigator-initiated trial from Indivior. LM has received research funding from the Alzheimer’s Society of Canada, Centre for Aging and Brain Health Innovation, Ontario Ministry of Health and Long-Term Care, and Brainsway, Ltd. TKR has received research support from Brain Canada, Brain and Behavior Research Foundation, BrightFocus Foundation, Canada Foundation for Innovation, Canada Research Chair, Canadian Institutes of Health Research, Centre for Aging and Brain Health Innovation, National Institutes of Health, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research and Innovation, and the Weston Brain Institute. TKR also received in-kind equipment support for an investigator-initiated study from Magstim, and in-kind research accounts from Scientific Brain Training Pro. TKR participated in 2021 and 2022 in an advisory board for Biogen Canada Inc. HA, CZ, HB, RZ, NH, SK, and KL report no competing interests."

"Funding This work was funded by Brain Canada, a Canada Research Chair, and the Labatt Family Network for Research on the Biology of Depression."

"HC and MCI participants were recruited for an AD prevention trial (Prevention of AD with Cognitive Remediation plus transcranial Direct Current Stimulation in Mild Cognitive Impairment and Depression (PACt-MD); NCT02386670) across five academic hospitals in Toronto, Canada. The complete clinical trial design and rationale have been reported previously []. All participants provided written informed consent as approved by the local Research Ethics Board and Clinical Trials Ontario. Eligibility criteria for all participants included: (1) no lifetime Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM 5) [] diagnosis of schizophrenia, bipolar disorder, or obsessive-compulsive disorder; (2) no significant neurological conditions impacting cognition or unstable medical illnesses; (3) no DSM 5 diagnosis of alcohol or other substance use disorder within the past 12 months; (4) no use of cognitive enhancers in the 6 weeks prior to entering the study; and (5) Montgomery–Asberg Depression Rating Scale [] (MADRS) score ≤ 10. Additional eligibility criteria for the MCI group included: (1) Age ≥ 60; and (2) DSM-5 diagnosis of Mild Neurocognitive Disorder. Additional eligibility criteria for the HC group included: (1) Age ≥ 60; (2) no DSM 5 diagnosis of Mild or Major Neurocognitive Disorder; and (3) no neuropsychological testing done in the 12 months prior to baseline assessment. In addition, MCI diagnosis was confirmed at a consensus conference that included the clinical psychiatrist of the participant, one or two principal investigators, the study neuropsychologist, and the research staff who administered the clinical, functional, and neuropsychological assessments. The EEG study was an optional portion of the parent study. Of those who consented and completed the EEG at baseline, 114 MCI and 44 HC participants were included in the final analyses (see CONSORT chart, Figs. S1 and S2 in ). Of note, PACt-MD also recruited participants with a major depressive disorder with or without MCI. These participants were not included in this analysis."