Table 5.

Correlation of brain amyloid load with blood biomarkers levels in the all-study participants and after stratification by PA levels.

		All participants		LMPA		HPA
Brain Aβ deposition (Ln Aβ)		β	p	β	p	β	p
Plasma Aβ1−42 (Ln Aβ1−42)	Unadjusted	−0.335	<0.001	−0.318	0.010	−0.408	<0.001
	Adjusted*	−0.290	0.001	−0.280	0.027	−0.389	0.001
Plasma Aβ1−40 (Ln Aβ1−40)	Unadjusted	−0.016	0.850	−0.069	0.584	0.020	0.864
	Adjusted*	−0.007	0.935	−0.092	0.478	0.028	0.812
Plasma APP669−711 (Ln APP669−711)	Unadjusted	0.071	0.402	0.035	0.783	0.081	0.480
	Adjusted*	0.055	0.519	0.095	0.464	0.000	0.999

Linear regression was performed between brain Aβ deposition and plasma Aβ₁₋₄₂, Aβ₁₋₄₀, and APP_669−711 in all participants and after stratification based on physical activity levels. Data were natural log transformed to better approximate normality and variance homogeneity. Physical activity was measured by the International Physical Activity Questionnaire (IPAQ), and participants were stratified based on low-to-moderate-level physical activity (LMPA) and high physical activity (HPA). P < 0.05 (italic) was considered significant. Adjusted^* represents analyses adjusted for age, sex, and APOE ε4-carrier status.