The increased burden of cardiovascular disease (CVD) that affects those disadvantaged by socioeconomic status (SES) is driven by a biological pathway that originates in the brain and may be potentially modifiable, according to a study published in the Journal of the American College of Cardiology.
In this study based on data from a retrospective, longitudinal, observational imaging study, investigators identified participants who underwent F-fluorodeoxyglucose positron emission tomography/computed tomography imaging for clinical evaluation between 2005 and 2008 (N=509).
Brain imaging data were available in a subset of 289. Participants were required to have ≥3 clinical encounter notes after index imaging to ensure adequate information for major adverse cardiac events (MACE) adjudication. Neighborhood-based SES factors were derived from the US Census Bureau’s 2015 American Community Survey 5-year Estimates and Massachusetts Uniform Crime Reporting database by the Federal Bureau of Investigation.
Neighborhood median income was negatively associated with stress-related neurobiological activity, measured as resting metabolic activity in the amygdala (AmygA), after adjusting for age and sex (standardized β -0.156; 95% CI, -0.267 to -0.042; P =.007). Income was negatively associated with arterial inflammation after adjusting for CVD risk factors (standardized β -0.098; 95% CI, -0.182 to -0.14; P =.022).
Several additional indices of SES were associated with AmygA; a lower AmygA was observed when neighborhood median income was divided into quartiles (standardized β -0.18; 95% CI, -0.26 to -0.06; P =.002).
Higher AmygA was observed when neighborhood crime was categorized into quartiles (standardized β 0.15; 95% CI, 0.01-0.21; P =.034).
Individuals experienced ≥1 MACE events during a median follow-up period of 4.0 years. There was a nearly 4-fold higher risk for MACE in individuals in the lowest vs the highest quartile of neighborhood median income (hazard ratio [HR] 3.91; 95% CI, 1.30-11.77; Cox regression P =.015), which remained significant after adjusting for CVD risk factors (HR 3.59; 95% CI, 1.19-10.85; P =.024).
This study is potentially limited in the generalizability of the findings due to the identification of patients who had undergone imaging for mostly cancer surveillance from a clinical database. Because of the unavailability of individual SES data, researchers used neighborhood SES measures, which have been shown to have an effect on individual stress beyond individual SES measures and have been associated with adverse health outcomes.
The researchers illuminated a stress-associated multi-organ system that links SES to CVD. Lower SES is associated with higher AmygA activity and is a predictor of MACE via a serial pathway that includes this activity, as well as bone marrow activity and arterial inflammation. Future studies should utilize individual-level SES measures that may yield further insights into these observed associations.
Several researchers acknowledge conflicts of interest. Please see reference for a full list of disclosures.
Tawakol A, Osborne MT, Wang Y, et al. Stress-associated neurobiological pathway linking socioeconomic disparities to cardiovascular disease. J Am Coll Cardiol. 2019;73(25):3243-3255.