Longitudinal studies into the variability of 18F-Flutemetamol uptake are lacking.
Therefore, the current study examined change in 18F-Flutemetamol uptake in 19 nondemented older adults (65 to 82 y old) who were either cognitively intact or had Mild Cognitive Impairment (MCI) who were scanned twice across 3.6 years.
Baseline and follow-up composite SUVRs were significantly correlated (0.96, P<0.001). Significant increases in the composite SUVR from baseline to follow-up were observed (P=0.002). For the total sample, the average difference over this time period when using the composite SUVR was 6.8%. Similar results were seen in subsets of the total sample (MCI vs. cognitively intact, amyloid positive vs. negative). Finally, a Reliable Change Index that exceeded ±0.046 SUVR units would indicate a significant change of 18F-Flutemetamol.
The current results extend the limited literature on longitudinal variability of 18F-Flutemetamol uptake across 3.6 years, which should give clinicians and researchers more confidence in the stability of this amyloid imaging agent in longer therapeutic and prevention trials in cognitive decline in MCI and Alzheimer disease.
*Department of Neurology, Center for Alzheimer’s Care, Imaging and Research
†Center for Quantitative Cancer Imaging, Huntsman Cancer Institute
‡Department of Radiology, University of Utah, Salt Lake City, UT
Supported by research grants from the National Institutes on Aging: R01AG055428. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Aging or the National Institutes of Health. Support was also provided by GE Healthcare and the Center for Quantitative Cancer Imaging, Huntsman Cancer Institute, University of Utah.
K.D. and J.M.H. received research funding from GE Healthcare. K.P.H. has no conflicts of interest.
Reprints: Kevin Duff, PhD, Center for Alzheimer’s Care, Imaging and Research, University of Utah, Department of Neurology, 650 Komas Drive #106-A, Salt Lake City, UT 84108 (e-mail: firstname.lastname@example.org).
Received September 10, 2018
Accepted December 1, 2018