Cerebral microbleeds on 7 Tesla MRI in preclinical Alzheimer's disease: The Medea‐7T study: Neuroimaging / Normal brain aging. (7th December 2020)

• Record Type: Journal Article
• Authors: Zwartbol, Maarten H.T.; Ghaznawi, Rashid; Blom, Kim; Kuijf, Hugo J.; Witkamp, Theo; Hendrikse, Jeroen; Geerlings, Mirjam I.
• Is Part Of: Alzheimer's & dementia. Volume 16(2020)Supplement 4
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-07
• Subjects: Alzheimer's disease -- Periodicals; Alzheimer Disease -- Periodicals; Dementia -- Periodicals; Démence; Maladie d'Alzheimer; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.83
• DOI: 10.1002/alz.044763
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Subjective cognitive decline is increasingly being viewed as an early cognitive marker of preclinical Alzheimer's disease (AD). Studies have recommended including AD biomarkers to increase the specificity of subjective cognitive decline, because of its etiological heterogeneity. We studied the prevalence and burden of cerebral microbleeds in persons with normal cognition, subjective memory impairment, cognitive impairment, and a clinical diagnosis mild cognitive impairment (MCI) or AD. Methods: Data are from 386 participants (68±9 years, 30% women) included in the Medea‐7T cohort, a diverse cohort of persons with normal cognition, patients with a history of vascular disease, and memory clinic patients. A 7T brain MRI was performed in all participants. Four cognitive stages were defined: 1) normal cognition (n=196); 2) subjective memory impairment (n=78); 3) cognitive impairment (defined as <1.5 SD below age, sex, and education adjusted Z‐scores in any cognitive domain within the study sample) (n=57); 4) MCI/AD diagnosed according to international criteria (n=36). CMBs were visually rated on 7T MRI according to established criteria. Age‐ and sex‐adjusted log‐binomial regression was performed to examine the association between the cognitive stages and presence of CMBs (yes vs. no). Results: Overall microbleed prevalence was 61%, with estimates per cognitive stage: normal cognitive function 60%, SCD 73%, cognitive impairment 55%, MCI and AD 47% (Figure 1). Age‐ and sex‐adjusted log‐binomial regression showed that—compared with the normal group—differences in microbleed prevalence were not statistically significant. Nonetheless, SCD showed an increased risk of CMBs (RR=1.18; 95% CI, 0.99‐1.41; p=0.06), whereas MCI/AD showed a decreased risk (RR=0.68; 95% CI, 0.45‐1.02; p=0.06), both approaching statistical significance. Conclusion: In this study, cerebral microbleeds on 7T MRI were highly prevalent in older persons with normal cognition, subjective memory impairment, and MCI/AD. Differences observed between groups may reflect differences in underlying dominant etiology.