Longitudinal Changes in Global Cerebral Blood Flow in Cognitively Normal Older Adults: A Phase‐Contrast MRI Study. Issue 5 (26th February 2022)

• Record Type: Journal Article
• Authors: Han, Hualu; Lin, Zixuan; Soldan, Anja; Pettigrew, Corinne; Betz, Joshua F.; Oishi, Kumiko; Li, Yang; Liu, Peiying; Albert, Marilyn; Lu, Hanzhang
• Is Part Of: Journal of magnetic resonance imaging. Volume 56:Issue 5(2022)
• Page Start: 1538
• Page End: 1545
• Publication Date: 2022-02-26
• Subjects: aging -- cerebral blood flow -- longitudinal -- phase‐contrast -- white matter hyperintensity; Magnetic resonance imaging -- Periodicals; 616
• DOI: 10.1002/jmri.28133
• Languages: English
• ISSNs: 1053-1807

Abstract

Abstract : Background: Characterization of blood supply changes in older individuals is important in understanding brain aging and diseases. However, prior studies largely focused on cross‐sectional design, thus change in cerebral blood flow (CBF) could not be assessed on an individual level. Purpose: To evaluate longitudinal short‐term changes in global CBF in cognitively normal older adults. Study Type: Prospective, longitudinal, and cohort. Population: One‐hundred twenty‐seven cognitive‐normal participants (mean age 69 ± 7 years, 47 males) underwent serial MRI with an average follow‐up time of 2.1 years. Field Strength/Sequence: 3 T phase‐contrast (PC), three‐dimensional magnetization‐prepared‐rapid‐acquisition‐of‐gradient‐echo (MPRAGE) and fluid‐attenuated inversion recovery (FLAIR) MRI. Assessment: Total CBF was measured with PC MRI allowing assessment of quantitative flow in four major feeding arteries by a trained radiologist with >3 years' experience (O.K.). Brain volume was obtained from MPRAGE MRI and measured by T1‐MultiAtlas MRICloud tool. The ratio between total CBF and brain volume yielded global CBF in mL/100 g/min. White matter hyperintensity (WMH) was measured automatically using a Bayesian probability approach on FLAIR. Statistical Tests: Linear mixed effect model was used to simultaneously assess cross‐sectional age‐differences and longitudinal age‐changes in CBF. Spearman rank correlation was used to evaluate the relationship between CBF change and WMH progression. A P ‐value of <0.05 (two‐tailed) was considered significant. Results: Global CBF decreased with age at a longitudinal rate of −0.56 mL/100 g/min/year (95% confidence interval [CI]: −1.09, −0.03), compared to a cross‐sectional rate of −0.26 mL/100 g/min/year (95% CI: −0.41, −0.11). Changes in CBF were significantly associated with progression of WMH (Spearman rank correlation r = −0.25), as those participants who had a more rapid CBF reduction had greater increases in WMH volumes and the relationship remained significant when adjusting for baseline vascular risk scores. Additionally, age‐related changes in whole‐brain volume were found to be −0.151%/year (95% CI: −0.186, −0.116). Data Conclusion: These findings suggest that brain aging in older adults is accompanied by a rapid longitudinal reduction in CBF, the rate of which is associated with white matter damage. Level of Evidence: 1 Technical Efficacy Stage: 2