DOI: 10.5061/dryad.v6wwpzh48
title: Data from: Flortaucipir PET uncovers relationships between tau and β-amyloid in aging, primary age related tauopathy, and Alzheimer disease

description: [18F]-Flortaucipir PET is considered a good biomarker of Alzheimer’s
 disease. However, it is unknown how flortaucipir is associated with the
 distribution of tau across brain regions and how these associations are
 influenced by β-amyloid. It is also unclear whether flortaucipir can
 detect tau in definite primary age-related tauopathy (PART). We identified
 248 individuals at Mayo Clinic that had undergone [18F]-flortaucipir PET
 during life, had died, and undergone an autopsy, 239 cases of which also
 had β-amyloid PET. We assessed nonlinear relationships between
 flortaucipir uptake in nine medial temporal and cortical regions, Braak
 tau stage and Thal β-amyloid phase using generalized additive models. We
 found that flortaucipir uptake was greater with increasing tau stage in
 all regions. Increased uptake at low tau stages in medial temporal regions
 was only observed in cases with high β-amyloid phase. Flortaucipir uptake
 linearly increased with β-amyloid phase in medial temporal and cortical
 regions. The highest flortaucipir uptake occurred with high Alzheimer’s
 disease neuropathologic change (ADNC) scores, followed by low-intermediate
 ADNC scores, then PART, with entorhinal cortex providing the best
 differentiation between groups. Flortaucipir PET had limited ability to
 detect PART and imaging defined PART did not correspond with
 pathologically defined PART. In summary, spatial patterns of flortaucipir
 mirrored histopathological tau distribution, were influenced by β-amyloid
 phase, and were useful for distinguishing different ADNC scores and PART.
description: These data are from 248 participants recruited from Mayo Clinic,
 Rochester, MN, who had flortaucipir PET imaging during life, had died, and
 had undergone an autopsy evaluation. All patients were enrolled into one
 of three NIH funded cohort studies including the Mayo Clinic Alzheimer’s
 Disease Research Center (PI: Petersen), The Mayo Clinic Study of Aging
 (PI: Petersen) and the Neurodegenerative Research Group (PIs:
 Josephs/Whitwell).
description: # Data sets for "Flortaucipir PET uncovers relationships between tau
 and β-amyloid in aging, primary age related tauopathy, and Alzheimer
 disease" Each of these file corresponds to a figure in the main paper
 or in the supplementary materials. ## `figure1.csv` * `Thal` is Thal phase
 which is measured by histopathology. This is an ordinal variable with no
 units. * `Braak` is Braak neurofibrillary tangle stage. This is an ordinal
 variable with no units. Braak stages are sometimes styled using Roman
 numerals. * `Group` is a composite variable representing how we combined
 Thal phase and Braak stage. --- ## `figure2.csv` * `region` is the
 location in the brain where the flortaucipir PET tracer was measured. The
 regions are as follows: 1. ERC, entorhinal cortex 2. Anterior HP or AHP,
 anterior hippocampus 3. Fusiform or FFG, fusiform gyrus 4. Inferior
 temporal or ITG, inferior temporal gyrus 5. Superior frontal or SFG,
 superior frontal gyrus 6. Precuneus or PRCU, precuneus 7. Superior
 parietal or SPG, superior parietal gyrus 8. Calcarine or CAL, calcarine 9.
 Precentral or PrCG, precentral gyrus * `thal` is the Thal phase as in
 `figure1.csv`. * `braak` is the Braak stage as in `figure1.csv`. *
 `estimates` corresponds to the model-based estimated geometric mean
 standardized uptake value ratio (SUVR) from the generalized additive
 model. This variable is a ratio and unitless although some researchers use
 the phrase "SUVR units." --- ## `figure3.csv` and
 `figure3_labels.csv1` This figure can be thought of as a 6 Thal phases
 (rows) by 7 Braak stages (columns) grid and within each "cell"
 is a 3x3 sub array corresponding to the 9 regions. The estimates for the
 figure are in a (6 * 3) x (7 * 3) = 18 x 21 matrix found in `figure3.csv`.
 They are scaled to the unit interval. The file `figure3_labels.csv` gives
 the coordinates for the region labels. * `position_x_axis` is the position
 on the x-axis in terms of the unit interval. * `position_y_axis` is the
 position on the y-axis in terms of the unit interval. * `roi` is the
 region of interest, or simply region, label. The regions here are
 abbreviated. See above for the mapping between abbreviation and region of
 interest. --- ## `figure4.csv` * `erc_tau` is the entorhinal cortex
 flortaucipir SUVR value for each individual in the study and is plotted in
 panel B. * `group` is the four-level composite group used throughout the
 paper. * `braak` is the Braak stage as in `figure1.csv`. * `thal` is the
 Thal phase as in `figure1.csv`. * `cerad` stands for "Consortium to
 Establish a Registry for Alzheimer’s Disease (CERAD)" and is an
 ordinal neuropathology variable. * `pib` is the Pittsburgh Compound B
 (PiB) group. PiB is the amyloid PET ligand used in this study. The label
 "PiB +" corresponds to an elevated (abnormal) PiB SUVR,
 "PiB -" corresponds to a normal PiB SUVR, and "No PiB"
 means the participant did not have a PiB scan. --- ## `figureS1.csv` *
 `region` is the 9-level region or region of interest (ROI) as in
 `figure2.csv`. * `position_x_axis` is the position on the x-axis for
 plotting. * `contrast` is an ordinal variable which indicates which Braak
 stages are being contrasted (or differenced). * `estimates` is the
 estimate for the contrast, or the estimated percentage difference based on
 the generalized additive models summarized in Figure 2. * `lcl`
 corresponds to the lower 95% confidence limit. * `ucl` corresponds to the
 upper 95% confidence limit. --- ## `figureS2_S4.csv` The data for Figure
 S2 and S4 are the same and can be thought of as a variation of Figure 2
 but using partial volume correction (PVC) to account for atrophy. Figure
 S2 has Braak stage on the x-axis and lines for Thal phase while Figure S4
 has Thal phase on the x-axis with lines for Braak stage. * `region` is the
 9-level region or region of interest (ROI) as in `figure2.csv`. * `thal`
 is the Thal phase as in `figure1.csv`. * `braak` is the Braak stage as in
 `figure1.csv`. * `estimates` corresponds to the model-based estimated
 geometric mean standardized uptake value ratio (SUVR) from the generalized
 additive model fit to PVC data. --- ## `figureS3.csv` This figure is
 similar to Figure S1 but here Thal phases are being contrast. * `region`
 is the 9-level region or region of interest (ROI) as in `figure2.csv`. *
 `position_x_axis` is the position on the x-axis for plotting. * `contrast`
 is an ordinal variable which indicates which Thal phases are being
 contrasted (or differenced). * `estimates` is the estimate for the
 contrast, or the estimated percentage difference in means based on the
 generalized additive models summarized in Figure 2. * `lcl` corresponds to
 the lower 95% confidence limit. * `ucl` corresponds to the upper 95%
 confidence limit. --- ## `figureS5.csv` This figure gives the estimated
 mean SUVR for combinations of Braak stage and Thal phase for six different
 model fits. * `model` is the model being fit. This is a categorical
 variable with six levels. * `region` is the 9-level region or region of
 interest (ROI) as in `figure2.csv`. * `position_y_axis` is the y-axis
 position for plotting. It corresponds to the Thal phase with jittering. *
 `braak` is the Braak stage as in `figure1.csv`. * `estimates` is the
 estimated geometric mean flortaucipir SUVR for the Braak-Thal combination
 for a particular model. * `lcl` corresponds to the lower 95% confidence
 limit. * `ucl` corresponds to the upper 95% confidence limit. --- ##
 `figureS6.csv` * `region` is the 9-level region or region of interest
 (ROI) as in `figure2.csv`. * `group` is an eight-level grouping variable
 indicating the person-level group. * `taupet` is the within-region,
 person-level flortaucipir PET SUVR value. --- ## `figureS7.csv` *
 `position_x_axis` gives the position on the x-axis (the Braak axis) for
 the point plotted. * `position_y_axis` gives the position on the y-axis
 (the Thal axis) for the point plotted. * `erc_group` is the entorhinal
 cortex (ERC) SUVR group. * `number_subjects` is the number of participants
 for the given combination of Thal, Braak, CERAD, and PiB. (For CERAD and
 PiB, see `figure4.csv`.) * `cerad` as in `figure4.csv`. * `pib` as in
 `figure4.csv`. --- ## `figureS8.csv` * `thal` is the Thal phase as in
 `figure1.csv`. * `centiloid` is the amyloid PET centiloid value. This is a
 rescaling of PiB whereby 0 represents the mean SUVR value for a reference
 group of controls and 100 represents the mean SUVR value for a reference
 group of individuals with Alzheimer's. Note that values below 0 and
 above 100 are possible. * `cerad` as in `figure4.csv`. * `group` is the
 four-level composite group used throughout the paper.