Effect of Stress-Related Neural Pathways on the Cardiovascular Benefit of Physical Activity.

Background: The mechanisms underlying the psychological and cardiovascular disease (CVD) benefits of physical activity (PA) are not fully understood.
Objectives: This study tested whether PA: 1) attenuates stress-related neural activity, which is known to potentiate CVD and for its role in anxiety/depression; 2) decreases CVD in part through this neural effect; and 3) has a greater impact on CVD risk among individuals with depression.
Methods: Participants from the Mass General Brigham Biobank who completed a PA survey were studied. A subset underwent ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomographic imaging. Stress-related neural activity was measured as the ratio of resting amygdalar-to-cortical activity (AmygA _C ). CVD events were ascertained from electronic health records.
Results: A total of 50,359 adults were included (median age 60 years [Q1-Q3: 45-70 years]; 40.1% male). Greater PA was associated with both lower AmygA _C (standardized β: -0.245; 95% CI: -0.444 to -0.046; P = 0.016) and CVD events (HR: 0.802; 95% CI: 0.719-0.896; P < 0.001) in multivariable models. AmygA _C reductions partially mediated PA's CVD benefit (OR: 0.96; 95% CI: 0.92-0.99; P < 0.05). Moreover, PA's benefit on incident CVD events was greater among those with (vs without) preexisting depression (HR: 0.860; 95% CI: 0.810-0.915; vs HR: 0.929; 95% CI: 0.910-0.949; P interaction = 0.011). Additionally, PA above guideline recommendations further reduced CVD events, but only among those with preexisting depression (P interaction = 0.023).
Conclusions: PA appears to reduce CVD risk in part by acting through the brain's stress-related activity; this may explain the novel observation that PA reduces CVD risk to a greater extent among individuals with depression.
Competing Interests: Funding Support and Author Disclosures This study is in part funded by National Institutes of Health (NIH) grants R56AR077187-01 and P01HL131478-05. This study was in part supported by NIH grants 1R01AR077187 (Dr Tawakol), P01HL131478 (Drs Tawakol and Fayad), K23HL151909 (Dr Osborne). Dr Osborne has received consulting fees from WCG Intrinsic Imaging, LLC, for unrelated work. Dr Choi has received support in part by funding from the National Institute of Mental Health (K08MH127413) and a NARSAD Brain and Behavior Foundation Young Investigator Award. Dr Smoller has received support for work outside the submitted research; is a member of the Scientific Advisory Board of Sensorium Therapeutics (with equity); has received an honorarium for an internal seminar at Tempus Labs and Biogen, Inc; and is PI of a study sponsored by 23andMe. Dr Tawakol has received grants from the National Institutes of Health, International Atomic Energy Agency, Osler/Harvard, and Lung Biotechnologies for work outside the submitted research. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)