Table 1.
Demographics for all participants with MCI who had longitudinal data
| Converted to AD | Other participants | p-value | |
|---|---|---|---|
| Participants (female) | 17 (9) | 99 (42) | 1.0000 |
| Age at baseline [years] | 72.05 (1.97) | 70.86 (0.69) | 1.0000 |
| Time between scans [years] | 2.04 (0.02) | 2.01 (0.01) | 1.0000 |
| Education [years] | 16.94 (0.57) | 16.44 (0.27) | 1.0000 |
| APOE ε4 [# alleles] | 1.06 (0.18) | 0.45 (0.06) | 0.1060* |
| MMSE at baseline [−] | 27.06 (0.50) | 28.35 (0.16) | 0.4672* |
| MMSE difference [−] | −3.65 (0.62) | −0.28 (0.20) | 0.0010 |
| ADAS13 at baseline [−] | 21.94 (1.37) | 12.11 (0.54) | <0.0001 |
| ADAS13 difference [−] | 8.06 (1.43) | −0.20 (0.43) | 0.0005 |
| CDR-SB at baseline [−] | 2.50 (0.20) | 1.23 (0.11) | <0.0001 |
| CDR-SB difference [−] | 2.68 (0.33) | −0.04 (0.12) | <0.0001 |
| Global thickness diff. [mm/year] | −0.033 (0.008) | −0.009 (0.002) | 0.1455* |
| AD regional thick. diff. [mm/year] | −0.041 (0.009) | −0.013 (0.002) | 0.1656* |
| WM Lesion vol. diff. [mm3/year] | 1199 (291) | 413 (57) | 0.3522* |
| Hippocampal vol. diff. [mm3/year] | −264 (31) | −58 (10) | <0.0001 |
| Ventricular vol. diff. [mm3/year] | 3949 (496) | 1439 (140) | 0.0024 |
| Total WM vol. diff. [mm3/year] | −5922 (979) | −3331 (346) | 0.4487* |
| AVF (baseline) | −0.594 (0.230) | −0.008 (0.106) | 0.6326* |
| AVF (difference) | −0.381 (0.053) | −0.146 (0.014) | 0.0089 |
| NDF (baseline) | 0.286 (0.248) | 0.872 (0.069) | 0.7300* |
| NDF (difference) | −0.434 (0.115) | −0.129 (0.028) | 0.3915* |
Standard errors of the mean are shown in parentheses, except for the first row where number of female participants is displayed. χ2 and two-tailed t tests were used to obtain the p-values. Difference defined as value at follow-up minus value at baseline. All tests were corrected using a Bonferroni correction for 21 comparisons (bolded represents significant when corrected, while * represents significant when uncorrected). An average negative AVF value at baseline indicates that the average individual of the replication sample had slightly higher white matter hyperintensities and ventricular volume when compared to the distribution of the original sample. An average positive NDF value at baseline in turn means that individuals of the replication sample had slightly higher hippocampal volume and cortical thickness when compared to the distribution of the original sample. The scale is largely arbitrary and is generally useful to compare across individuals. (MMSE: Mini-Mental State Exam; ADAS-Cog 13: Alzheimer’s Disease Assessment Scale; CDR-SB: Clinical Dementia Rating – Sum of Boxes; MCI: mild cognitive impairment; AVF: age- and vascular-related factor; NDF: neurodegenerative factor)