TABLE 2.
Partially standardized beta coefficients from linear mixed models examining exercise on Alzheimer's disease‐related biomarkers at baseline, over time, and across EYO.
| Outcome variable | Baseline exercise Model 1 β (SE) |
Baseline exercise x time Model 1 β (SE) |
Baseline exercise x time x EYO Model 2 β (SE) |
Exercise change category x time Model 3 β (SE) |
Exercise change category x time x EYO Model 4 β (SE) |
|---|---|---|---|---|---|
| CSF Aβ42 | 0.08 (0.06) | 0.02 (0.02) | 0.00 (0.02) | −0.03 (0.02) | 0.02 (0.02) |
| CSF Aβ42/Aβ40 | 0.05 (0.06) | −0.01 (0.01) | 0.01 (0.02) | −0.03 (0.01) | 0.02 (0.02) |
| CSF p‐tau/Aβ42 | −0.14 (0.06) * | −0.02 (0.01) | −0.01 (0.02) | 0.01 (0.01) | −0.02 (0.01) |
| CSF p‐tau | −0.16 (0.06) ** | −0.01 (0.01) | −0.01 (0.02) | −0.00 (0.01) | −0.01 (0.02) |
| CSF t‐tau | −0.21 (0.06) *** | 0.01 (0.02) | −0.00 (0.02) | −0.02 (0.02) | −0.03 (0.02) |
| Right hippocampal volume | 0.12 (0.06) | 0.04 (0.01) * | 0.06 (0.01) *** | 0.04 (0.02) * | 0.00 (0.01) |
| Left hippocampal volume | 0.14 (0.06) | 0.04 (0.02) * | 0.06 (0.02) * | 0.04 (0.02) | −0.00 (0.02) |
| Total cortical volume | 0.11 (0.04) * | 0.01 (0.01) | 0.03 (0.01) * | 0.01 (0.01) | 0.03 (0.01) * |
| Total subcortical gray matter volume | 0.12 (0.05) * | 0.01 (0.01) | 0.03 (0.01) * | 0.01 (0.01) | 0.01 (0.01) |
| Total gray matter volume | 0.12 (0.04) * | 0.01 (0.01) | 0.03 (0.01) * | 0.01 (0.01) | 0.03 (0.01) * |
| White matter hyperintensities | −0.10 (0.06) | −0.00 (0.02) | 0.01 (0.02) | −0.05 (0.02) | −0.01 (0.02) |
| Aβ (PiB) | −0.18 (0.06) ** | −0.02 (0.01) * | 0.04 (0.01) *** | −0.00 (0.01) | 0.01 (0.01) |
Note. All results presented as partially standardized beta coefficient (standard error). Predictor variables are standardized; outcome variables are not. Separate models run for each outcome variable. Significant results reported here have been corrected for multiple comparisons using FDR, applied within each outcome variable (i.e., for CSF 5 outcomes x 4 models = 20 P values corrected). FDR correction was applied to the highest order interaction term only (i.e., FDR was not applied to main effects from the same model for Models 1 and 3). Data for the main effect of exercise and exercise x time taken from the same model. All CSF and PiB outcome variables were log transformed. Covariates are as follows CSF: age, APOE ε4 status, mutation rank, family mutation; MRI: age, sex, intracranial volume, mutation rank, family mutation; PiB: APOE ε4 status; Exercise categories were created based on a 365 minute/week cut‐off and classified as 1 = decreased, 2 = remained low, 3 = remained high, 4 = increased, based on follow‐up data.
Abbreviations: Aβ, amyloid beta; APOE, apolipoprotein E; CSF, cerebrospinal fluid; EYO, estimated years from expected symptom onset; FDR, false discovery rate; MRI, magnetic resonance imaging; PiB, Pittsburgh compound B; p‐tau, phosphorylated tau; SE, standard error; t‐tau, total tau; β, partially standardized beta coefficient.
P < 0.05.
P < 0.01.
P < 0.001 (q values, i.e., FDR corrected, for interaction terms).