Objective: To investigate the association of adherence to a healthy lifestyle with a panel of brain structural markers in middle-aged and older adults.
Design: Cross-sectional and prospective study design.
Setting: PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study in China and UK Biobank (UKB).
Participants: 2,413 participants in PRECISE and 19,822 participants in UKB.
Exposures: A healthy lifestyle score (0-5) was constructed based on five modifiable lifestyle factors: healthy diet, physically active, non-current-smoking, non-alcohol consumption (in PRECISE)/moderate alcohol consumption (in UKB), and healthy body weight.
Main Outcomes: Validated multimodal neuroimaging markers were derived from brain magnetic resonance imaging (MRI).
Results : In the cross-sectional analysis of PRECISE, participants who adopted four or five low-risk lifestyle factors had larger total brain volume (TBV; β= 0.12, 95%CI: -0.02, 0.26; p-trend = 0.048) and gray matter volume (GMV; β= 0.16, 95%CI: 0.01, 0.30; p-trend = 0.047), smaller white matter hyperintensity volume (WMHV; β= -0.35, 95%CI: -0.50, -0.20; p-trend <0.001) and lower odds of lacune (Odds Ratio [OR]=0.48, 95%CI: 0.22, 1.08; p-trend = 0.03), compared to those with zero or one low-risk factors. Meanwhile, in the prospective analysis in UKB (with a median of 7.7 years follow-up), similar associations were observed between the number of low-risk lifestyle factors (4-5 vs 0-1) and TBV (β= 0.22, 95%CI: 0.16, 0.28; p-trend <0.001), GMV (β= 0.26, 95%CI: 0.21, 0.32; p-trend < 0.001), white matter volume (WMV; β= 0.08, 95%CI: 0.01, 0.15; p-trend = 0.001), hippocampus volume (β= 0.15, 95%CI: 0.08, 0.22; p-trend = <0.001), and WMHV burden (β= -0.23, 95%CI: -0.29, -0.17; p-trend < 0.001). Those with four or five low-risk lifestyle factors showed approximately 2.0-5.8 years of delay in aging of brain structure.
Conclusion: Adherence to a healthier lifestyle was associated with a lower degree of neurodegeneration-related brain structural markers in middle-aged and older adults.