Vascular Contributions to Neurodegeneration: Protocol of the COMPASS-ND Study

Abstract

Objective: To describe the neuroimaging and other methods for assessing vascular contributions to neurodegeneration in the Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) study, a Canadian multi-center, prospective longitudinal cohort study, including reliability and feasibility in the first 200 participants. Methods: COMPASS-ND includes persons with Alzheimer’s disease (AD; n = 150), Parkinson’s disease (PD) and Lewy body dementias (LBDs) (200), mixed dementia (200), mild cognitive impairment (MCI; 400), subcortical ischemic vascular MCI (V-MCI; 200), subjective cognitive impairment (SCI; 300), and cognitively intact elderly controls (660). Magnetic resonance imaging (MRI) was acquired according to the validated Canadian Dementia Imaging Protocol and visually reviewed by either of two experienced readers blinded to clinical characteristics. Other relevant assessments include history of vascular disease and risk factors, blood pressure, height and weight, cholesterol, glucose, and hemoglobin A1c. Results: Analyzable data were obtained in 197/200 of whom 18 of whom were clinically diagnosed with V-MCI or mixed dementia. The overall prevalence of infarcts was 24.9%, microbleeds was 24.6%, and high white matter hyperintensity (WMH) was 31.0%. MRI evidence of a potential vascular contribution to neurodegeneration was seen in 12.9%–40.0% of participants clinically diagnosed with another condition such as AD. Inter-rater reliability was good to excellent. Conclusion: COMPASS-ND will be a useful platform to study vascular brain injury and its association with risk factors, biomarkers, and cognitive and functional decline across multiple age-related neurodegenerative diseases. Initial findings show that MRI-defined vascular brain injury is common in all cognitive syndromes and is under-recognized clinically.

The Relationship Between Hearing and Mild Behavioral Impairment and the Influence of Sex: A Study of Older Adults Without Dementia from the COMPASS-ND Study

“…Participants include persons with dementia as well as mild cognitive impairment (MCI), subjective cognitive decline (SCD), and cognitively normal (CN) controls. Participants with clinical diagnoses were primarily recruited from specialty clinics, although healthy controls and those with subjective cognitive complaints were also enrolled through non-clinical referral sources [ 36 ]. Clinical and cognitive data, sociodemographic details, biomarkers, structural brain imaging, and measures of sensory function are collected.…”

Vascular Brain Lesions, Cognitive Reserve, and Their Association with Cognitive Profile in Persons with Early-Stage Cognitive Decline

“…According to COMPASS-ND inclusion and exclusion criteria, participants were required to have a Montreal Cognitive Assessment (MoCA) score greater than 12, no history of ongoing drug or alcohol misuse, and no other significant chronic brain diseases. For the purpose of this study, patients with MCI were recruited into the V-MCI group if clinical CT or MRI neuroimaging showed two or more supratentorial infarcts [ 9 ]. Of 409 participants, we excluded 223 participants that had diagnoses other than SCI, MCI, or V-MCI, 1 participant with missing data on ethnicity, 1 participant with missing data on the vascular lesion burden score, 1 participant with missing data on infarcts, and 20 participants with missing data on cognitive reserve, leaving 200 total participants for our analysis.…”

“…Vascular brain injury was defined as the presence of either brain infarcts or high WMH. Additionally, we analyzed a combined variable, termed “high vascular lesion burden”, defined as the presence of two or more supratentorial brain infarcts or beginning confluent or confluent WMH on the Age-Related White Matter Changes scale [ 27 ], which was hypothesized to be a threshold for a potential vascular contribution to cognitive impairment [ 9 ].…”

“…The following sequences were used: 3D T1, PD/T2, FLAIR, gradient echo, resting state fMRI, and DTI [6]. MRI vascular lesions were identified visually centrally by readers at either the University of Calgary and Sunnybrook Hospital, Toronto [6,10] according to Standards for Reporting Vascular Changes on Neuroimaging [26]. WMH was grade according to the Fazekas scale [27], summing the periventricular and subcortical scores to give a total range of 0-6.…”

Sex‐specific neuropsychological correlates of apathy and depression across neurodegenerative disorders

“…Data used in this study were from the fifth data release of the Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) Study, a Canada-wide multi-centre prospective longitudinal cohort study investigating various etiologies of neurodegeneration (http://www.ccna-ccnv.ca/). [18][19][20] The sample included participants with MCI, vascular MCI (VMCI), AD, MD, FTD, PD, as well as CU controls. Sample size was determined so that sex distribution of the groups would be adequate to enable the analysis of how sex impacts the expression of different types of dementias.…”