The contribution of syndemic conditions to cardiovascular disease risk

The Triad Na+ Activated Na+ Channel (Nax)-Salt Inducible KINASE (SIK) and (Na+ + K+)-ATPase: Targeting the Villains to Treat Salt Resistant and Sensitive Hypertension

The Na⁺-activated Na⁺ channel (Nax) and salt-inducible kinase (SIK) are stimulated by increases in local Na⁺ concentration, affecting (Na⁺ + K⁺)-ATPase activity. To test the hypothesis that the triad Nax/SIK/(Na⁺ + K⁺)-ATPase contributes to kidney injury and salt-sensitive hypertension (HTN), uninephrectomized male Wistar rats (200 g; n = 20) were randomly divided into 4 groups based on a salt diet (normal salt diet; NSD-0.5% NaCl-or high-salt diet; HSD-4% NaCl) and subcutaneous administration of saline (0.9% NaCl) or deoxycorticosterone acetate (DOCA, 8 mg/kg), as follows: Control (CTRL), CTRL-Salt, DOCA, and DOCA-Salt, respectively. After 28 days, the following were measured: kidney function, blood pressure, (Na⁺ + K⁺)-ATPase and SIK1 kidney activities, and Nax and SIK1 renal expression levels. SIK isoforms in kidneys of CTRL rats were present in the glomerulus and tubular epithelia; they were not altered by HSD and/or HTN. CTRL-Salt rats remained normotensive but presented slight kidney function decay. HSD rats displayed augmentation of the Nax/SIK/(Na⁺ + K⁺)-ATPase pathway. HTN, kidney injury, and kidney function decay were present in all DOCA rats; these were aggravated by HSD. DOCA rats presented unaltered (Na⁺ + K⁺)-ATPase activity, diminished total SIK activity, and augmented SIK1 and Nax content in the kidney cortex. DOCA-Salt rats expressed SIK1 activity and downregulation in (Na⁺ + K⁺)-ATPase activity in the kidney cortex despite augmented Nax content. The data of this study indicate that the (Na⁺ + K⁺)-ATPase activity response to SIK is attenuated in rats under HSD, independent of HTN, as a mechanism contributing to kidney injury and salt-sensitive HTN.

Structural Inequities for Historically Underserved Communities in the Adoption of Stroke Certification in the United States

Importance

Stroke centers are associated with better outcomes. There is substantial literature surrounding disparities in stroke outcomes for underserved populations. However, the existing literature has focused primarily on discrimination at the individual or institutional level, and studies of structural discrimination in stroke care are scant.

Objective

To examine differences in hospitals' likelihood of adopting stroke care certification between historically underserved and general communities.

Design, Setting, and Participants

This study combined a data set of hospital stroke certification from all general acute nonfederal hospitals in the continental US from January 1, 2009, to December 31, 2019, with national, hospital, and census data to define historically underserved communities by racial and ethnic composition, income distribution, and rurality. For all categories except rurality, communities were categorized by the composition and degree of segregation of each characteristic. Cox proportional hazard models were then estimated to compare the hazard of adopting stroke care certification between historically underserved and general communities, adjusting for population size and hospital bed capacity. Data were analyzed from June 2021 to April 2022.

Main Outcomes and Measures

Hospitals' likelihood of adopting stroke care certification.

Results

A total of 4984 hospitals were included. From 2009 to 2019, the total number of hospitals with stroke certification grew from 961 to 1763. Hospitals serving Black, racially segregated communities had the highest hazard of adopting stroke care certification (hazard ratio [HR], 1.67; 95% CI, 1.41-1.97) in models not accounting for population size, but their hazard was 26% lower than among those serving non-Black, racially segregated communities (HR, 0.74; 95% CI, 0.62-0.89) in models controlling for population and hospital size. Adoption hazard was lower in low-income communities compared with high-income communities, regardless of their level of economic segregation, and rural hospitals were much less likely to adopt any level of stroke care certification relative to urban hospitals (HR, 0.43; 95% CI, 0.35-0.51).

Conclusions and Relevance

In this analysis of stroke certification adoption across acute care hospitals in the US from 2009 to 2019, hospitals in low-income and rural communities had a lower likelihood of receiving stroke certification than hospitals in general communities. Hospitals operating in Black, racially segregated communities had the highest likelihood of adopting stroke care, but because these communities had the largest population, patients in these communities had the lowest likelihood of access to stroke-certified hospitals when the model controlled for population size. These findings provide empirical evidence that the provision of acute neurological services is structurally inequitable across historically underserved communities.

How Early Stressful Life Experiences Combine With Adolescents' Conjoint Health Risk Trajectories to Influence Cardiometabolic Disease Risk in Young Adulthood

Research has primarily focused on additive (unique) associations between early stressful life experiences (specifically, socioeconomic adversity and maltreatment) and young adults' cardiometabolic disease risk without considering multiplicative (synergistic) influences. Furthermore, research has not fully considered the varying patterns of health risk trajectories (e.g., substance use, obesogenic-related behaviors, depressive symptoms) across adolescence and the transition to young adulthood that may link earlier stressful experiences and later cardiometabolic disease risk. This study examined heterogeneity in conjoint health risk trajectories from adolescence to the transition to young adulthood and their additive and multiplicative (synergistic) influences with early stressful life experiences on cardiometabolic disease risk in young adulthood using data from the National Longitudinal Study of Adolescent to Adult Health (n = 9,421; 55.6% female) over a period of 13 years. Four distinct conjoint health risk trajectories were identified considering trajectories of substance use behaviors, obesogenic-related behaviors, and depressive symptoms: (a) overall high-risk, (b) behavioral risks, (c) psycho-obesogenic risks, and (d) overall low-risk. Socioeconomic adversity and maltreatment were additively and multiplicatively associated with cardiometabolic disease risk in young adulthood. Individuals with overall high-risk conjoint trajectories averaged higher cardiometabolic disease risk in young adulthood when they were exposed to early socioeconomic adversity. Implications for personalized interventions for individuals who have experienced multiple forms of health risks are discussed.

Obesity and Morbidity Risk in the U.S. Veteran

The obesity epidemic in the United States has been well documented and serves as the basis for a number of health interventions across the nation. However, those who have served in the U.S. military (Veteran population) suffer from obesity in higher numbers and have an overall disproportionate poorer health status when compared to the health of the older non-Veteran population in the U.S. which may further compound their overall health risk. This study examined both the commonalities and the differences in obesity rates and the associated co-morbidities among the U.S. Veteran population, utilizing data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS). These data are considered by the Centers for Disease Control and Prevention (CDC) to be the nation’s best source for health-related survey data, and the 2018 version includes 437,467 observations. Study findings show not only a significantly higher risk of obesity in the U.S. Veteran population, but also a significantly higher level (higher odds ratio) of the associated co-morbidities when compared to non-Veterans, including coronary heart disease (CHD) or angina (odds ratio (OR) = 2.63); stroke (OR = 1.86); skin cancer (OR = 2.18); other cancers (OR = 1.73); chronic obstructive pulmonary disease (COPD) (OR = 1.52), emphysema, or chronic bronchitis; arthritis (OR = 1.52), rheumatoid arthritis, gout, lupus, or fibromyalgia; depressive disorders (OR = 0.84), and diabetes (OR = 1.61) at the 0.95 confidence interval level.