Table 1.
Demographics, cognitive status, vascular risk factors, and AD imaging biomarkers of participant groups in the baseline
| Total (n=230) | Control (n=106) | Converter (n=52) | Impaired (n=72) | p-value§§ | |
|---|---|---|---|---|---|
| Age, years (mean ± SD§) | 73.7±6.7 | 73.2±6.6 | 73.1±6.7 | 74.8±6.9 | 0.418 |
| Sex | |||||
| Men (n (%)) | 121 (52.6) | 54 (50.9) | 26 (50) | 41 (56.9) | 0.669 |
| Women (n (%)) | 109 (47.7) | 52 (49.1) | 26 (50) | 31 (43.1) | |
| Race | |||||
| Caucasian (n (%)) | 197 (85.6) | 93 (87.8) | 43 (82.7) | 61 (84.7) | 0.466 |
| African-American (n (%)) | 25 (10.9) | 11 (10.4) | 6 (11.5) | 8 (11.2) | |
| Native American (n (%)) | 1 (<1) | 0 (0) | 1 (1.9) | 0 (0) | |
| Unknown (n (%)) | 7 (3) | 2 (1.8) | 2 (3.9) | 3 (4.1) | |
| MMSE score (median (Q1–Q3))§ | 29 (28–30) | 29 (29–30) | 29 (28–30)### | 28 (26–29)*** | <0.001 |
| CDR-SB (median (min–max)) | 0 (1) | 0 (0–0.5) | 0 (0–0.5)### | 1.5 (0.5–6)*** | <0.001 |
| PACC score (median (Q1–Q3)) | 0.04 (−0.21–0.25) | 0.13 (−0.03–0.41) | 0.084 (−0.15–0.23)# | −0.23 (−0.41–0.04)*** | <0.001 |
| WMH volume, mm3 (mean ± SD) | 16,072±24,128 | 18,024±19,131 | 21,819±18,562 | 29,603±26,163** | 0.005 |
| Ln ICA Ca score (median (Q1–Q3)) | 3.2 (0–4.8) | 3.4 (0.69–4.8) | 2.9 (0–4.05) | 3.2 (0–5.2) | 0.349 |
| Ln ICA Ca volume (median (Q1–Q3)) | 3.7 (0–4.9) | 3.94 (1.55–4.96) | 3.6 (0–4.4) | 3.5 (0–5.2) | 0.520 |
| Total hippocampal volume, mm3 (mean ± SD) | 7004±967.6 | 7397±793 | 6991±844# | 6397±1008*** | <0.001 |
| AD cortical signature thickness, mm (mean ± SD) | 2.5±0.15 | 2.5±0.12 | 2.5±0.13# | 2.4±0.17*** | <0.001 |
| Centiloid (mean ± SD) | 6.9 (69.9) | 3.4±35.3 | 66.5±83.2 | 15.3±75.1*** | <0.001 |
| Amyloid positivity (negative/positive) | 114/116 | 70/36 | 23/29 | 21/51 | <0.001 |
Asterisks represent significant post hoc tests following the Kruskal-Wallis or ANOVA models: *<0.05, **<0.005, and ***<0.0001 represent post hoc models showing the significant difference from the control group while #<0.05, ##<0.005, and ###<0.0001 show significant difference from the impaired group
Abbreviations: Control, participants with CDR = 0 throughout all visits, Converter: participants converting from CDR = 0 to CDR > 0 in any of the follow-up visits, Impaired, participants with CDR > 0 in the baseline visit, MMSE, Mini-Mental State Examination, CDR, Clinical Dementia Rating Scale, CDR-SB, Clinical Dementia Rating Scale Sum of Boxes, PACC, Preclinical Alzheimer Cognitive Composite, WMH volume, white matter hyperintensities volume, AA, African-American, C, Caucasian, Nat, Native American, U, unknown race, Ln ICA Ca score/volume, natural log-transformed internal carotid artery Agatston calcium score/volume, AD cortical signature thickness, cortical thickness in signature regions affected in Alzheimer disease (see Dincer et al. 2020), Centiloid, measure of global amyloid disposition based on the conversion of PIB or AV45 PET SUVRs to a standardized scale. Amyloid positivity was defined based on Centiloid values > 16.4
§Data is reported in form of mean ±standard deviation (SD) for normally distributed variables and as median plus the first and third quartiles (Q1–Q3) for variables without normal distribution. Normality was determined using the Kolmogorov-Smirnov goodness-of-fit test
§§Kruskal-Wallis test was used to compare ICA Ca score and volume, MMSE, and PACC scores between the three baseline groups. Comparison for all other variables was conducted using an ANOVA model. Bold values indicate the test with statistical significance considering a threshold of 0.05