Elevated fibroblast growth factor-23 (FGF23) is an established marker of cardiovascular disease. The underlying reason(s) for the rise accompanying cardiovascular health decline are unclear. Prior ...studies have shown that FGF23 concentrations are associated with markers of inflammation and insulin resistance but they have been limited by a focus on persons with chronic kidney disease (CKD) and lack of race and sex diversity. The objective of this study was to examine the associations of FGF23 and markers of inflammation, insulin resistance, and anthropometrics in a large cohort of community-dwelling adults.
Associations of FGF23 with markers of inflammation interleukin-6 (IL-6), IL-10, high sensitivity-CRP (hsCRP), insulin utilization resistin, adiponectin, homeostatic model assessment of insulin resistance (HOMA-IR) and anthropometrics BMI and waist circumference (WC) were examined cross-sectionally in a 1,040 participants randomly selected from the Reason for Geographic and Racial Differences in Stroke (REGARDS) Study, a national study of black and white adults ≥45 years. Effect modification by race and CKD status was tested, and stratified models were analyzed accordingly.
Median FGF23 concentration was 69.6 RU/ml (IQR: 53.2, 102.7). Higher quartiles of FGF23 were associated with higher mean concentrations of IL-6, IL-10, hsCRP and resistin (Ptrend<0.001 for all). There were no significant differences in HOMA-IR, adiponectin concentrations, BMI, or WC across FGF23 quartiles in the crude analyses. CKD significantly modified the relationships between FGF23 and inflammatory markers, HOMA-IR, BMI and WC (P ≤ 0.01 for all). In linear regression models adjusted for sociodemographic and clinical variables, FGF23 was positively associated with IL-6, hsCRP, IL-10, HOMA-IR, BMI and WC in individuals without CKD, but not among individuals with CKD. Additionally, FGF23 was positively associated with resistin irrespective of CKD status.
Elevated FGF23 concentrations may be considered a biomarker for decline in metabolic function among individuals with normal kidney function.
Vitamin D is an important prohormone for optimal intestinal calcium absorption for mineralization of bone. Because the vitamin D receptor is present in multiple tissues, there has been interest in ...evaluating other potential functions of vitamin D, particularly, in cardiovascular diseases (CVD). Cross-sectional studies have reported that vitamin D deficiency is associated with increased risk of CVD, including hypertension, heart failure, and ischemic heart disease. Initial prospective studies have also demonstrated that vitamin D deficiency increases the risk of developing incident hypertension or sudden cardiac death in individuals with preexisting CVD. Very few prospective clinical studies have been conducted to examine the effect of vitamin D supplementation on cardiovascular outcomes. The mechanism for how vitamin D may improve CVD outcomes remains obscure; however, potential hypotheses include the downregulation of the renin-angiotensin-aldosterone system, direct effects on the heart, and vasculature or improvement of glycemic control. This review will examine the epidemiologic and clinical evidence for vitamin D deficiency as a cardiovascular risk factor and explore potential mechanisms for the cardioprotective effect of vitamin D.
Atrial fibrillation (AF) is common in patients with life-threatening cancer and those undergoing active cancer treatment. However, data from subjects with a history of non–life-threatening cancer and ...those who do not require active cancer treatment are lacking. A total of 15,428 (mean age 66 ± 8.9 years; 47% women; 45% blacks) participants from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study with baseline data on previous cancer diagnosis and AF were included. Participants with life-threatening cancer and active cancer treatment within 2 years of study enrollment were excluded. History of cancer was identified using computer-assisted telephone interviews. AF cases were identified from baseline electrocardiogram data and by a self-reported history of a previous diagnosis. Logistic regression was used to examine the cross-sectional association between cancer diagnosis and AF. A total of 2,248 (15%) participants had a diagnosis of cancer and 1,295 (8.4%) had AF. In a multivariable logistic regression model adjusted for sociodemographic characteristics (age, gender, race, education, income, and region of residence) and cardiovascular risk factors (systolic blood pressure, high-density lipoprotein cholesterol, total cholesterol, C-reactive protein, body mass index, smoking, diabetes, antihypertensive and lipid-lowering agents, left ventricular hypertrophy, and cardiovascular disease), those with cancer were more likely to have prevalent AF than those without cancer (odds ratio 1.19, 95% confidence interval 1.02 to 1.38). Subgroup analyses by age, sex, race, cardiovascular disease, and C-reactive protein yielded similar results. In conclusion, AF was more prevalent in participants with a history of non–life-threatening cancer and those who did not require active cancer treatment in REGARDS.
Nonalcoholic fatty liver disease (NAFLD) is prevalent and may affect cognitive function. We studied associations of NAFLD with risk of cognitive impairment. Secondarily we evaluated liver biomarkers ...(alanine aminotransferase (ALT), aspartate aminotransferase (AST), their ratio, and gamma-glutamyl transpeptidase).
In a prospective cohort study, the REasons for Geographic and Racial Differences in Stroke, among 30,239 black and white adults aged ≥45,495 cases of incident cognitive impairment were identified over 3.4 years follow up. Cognitive impairment was identified as new impairment in two of three cognitive tests administered every two years during follow up; word list learning and recall, and verbal fluency. 587 controls were selected from an age, race, sex-stratified sample of the cohort. The fatty liver index was used to define baseline NAFLD. Liver biomarkers were measured using baseline blood samples.
NAFLD at baseline was associated with a 2.01-fold increased risk of incident cognitive impairment in a minimally adjusted model (95% CI 1.42, 2.85). The association was largest in those aged 45-65 (p interaction by age = 0.03), with the risk 2.95-fold increased (95% CI 1.05, 8.34) adjusting for cardiovascular, stroke and metabolic risk factors. Liver biomarkers were not associated with cognitive impairment, except AST/ALT >2, with an adjusted OR 1.86 (95% CI 0.81, 4.25) that did not differ by age.
A laboratory-based estimate of NAFLD was associated with development of cognitive impairment, particularly in mid-life, with a tripling in risk. Given its high prevalence, NAFLD may be a major reversible determinant of cognitive health.
Stroke is the fifth-highest cause of death in the US and a leading cause of serious long-term disability with particularly high risk in Black individuals. Quality risk prediction algorithms, free of ...bias, are key for comprehensive prevention strategies.
To compare the performance of stroke-specific algorithms with pooled cohort equations developed for atherosclerotic cardiovascular disease for the prediction of new-onset stroke across different subgroups (race, sex, and age) and to determine the added value of novel machine learning techniques.
Retrospective cohort study on combined and harmonized data from Black and White participants of the Framingham Offspring, Atherosclerosis Risk in Communities (ARIC), Multi-Ethnic Study for Atherosclerosis (MESA), and Reasons for Geographical and Racial Differences in Stroke (REGARDS) studies (1983-2019) conducted in the US. The 62 482 participants included at baseline were at least 45 years of age and free of stroke or transient ischemic attack.
Published stroke-specific algorithms from Framingham and REGARDS (based on self-reported risk factors) as well as pooled cohort equations for atherosclerotic cardiovascular disease plus 2 newly developed machine learning algorithms.
Models were designed to estimate the 10-year risk of new-onset stroke (ischemic or hemorrhagic). Discrimination concordance index (C index) and calibration ratios of expected vs observed event rates were assessed at 10 years. Analyses were conducted by race, sex, and age groups.
The combined study sample included 62 482 participants (median age, 61 years, 54% women, and 29% Black individuals). Discrimination C indexes were not significantly different for the 2 stroke-specific models (Framingham stroke, 0.72; 95% CI, 0.72-073; REGARDS self-report, 0.73; 95% CI, 0.72-0.74) vs the pooled cohort equations (0.72; 95% CI, 0.71-0.73): differences 0.01 or less (P values >.05) in the combined sample. Significant differences in discrimination were observed by race: the C indexes were 0.76 for all 3 models in White vs 0.69 in Black women (all P values <.001) and between 0.71 and 0.72 in White men and between 0.64 and 0.66 in Black men (all P values ≤.001). When stratified by age, model discrimination was better for younger (<60 years) vs older (≥60 years) adults for both Black and White individuals. The ratios of observed to expected 10-year stroke rates were closest to 1 for the REGARDS self-report model (1.05; 95% CI, 1.00-1.09) and indicated risk overestimation for Framingham stroke (0.86; 95% CI, 0.82-0.89) and pooled cohort equations (0.74; 95% CI, 0.71-0.77). Performance did not significantly improve when novel machine learning algorithms were applied.
In this analysis of Black and White individuals without stroke or transient ischemic attack among 4 US cohorts, existing stroke-specific risk prediction models and novel machine learning techniques did not significantly improve discriminative accuracy for new-onset stroke compared with the pooled cohort equations, and the REGARDS self-report model had the best calibration. All algorithms exhibited worse discrimination in Black individuals than in White individuals, indicating the need to expand the pool of risk factors and improve modeling techniques to address observed racial disparities and improve model performance.
Stroke mortality is 30% higher in the rural United States. This could be because of either higher incidence or higher case fatality from stroke in rural areas.
The urban-rural status of 23 280 ...stroke-free participants recruited between 2003 and 2007 in the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) was classified using the Rural-Urban Commuting Area scheme as residing in urban, large rural town/city, or small rural town or isolated areas. The risk of incident stroke was assessed using proportional hazards analysis, and case fatality (death within 30 days of stroke) was assessed using logistic regression. Models were adjusted for demographics, traditional stroke risk factors, and measures of socioeconomic status.
After adjustment for demographic factors and relative to urban areas, stroke incidence was 1.23-times higher (95% confidence intervals, 1.01-1.51) in large rural town/cities and 1.30-times higher (95% confidence intervals, 1.03-1.62) in small rural towns or isolated areas. Adjustment for risk factors and socioeconomic status only modestly attenuated this association, and the association became marginally nonsignificant (
=0.071). There was no association of rural-urban status with case fatality (
>0.47).
The higher stroke mortality in rural regions seemed to be attributable to higher stroke incidence rather than case fatality. A higher prevalence of risk factors and lower socioeconomic status only modestly contributed to the increased risk of incident stroke risk in rural areas. There was no evidence of higher case fatality in rural areas.
To summarize overall patterns of the impact of neighborhood socioeconomic status (nSES) on stroke incidence and uncover potential gaps in the literature, we conducted a systematic review of studies ...examining the association between nSES and stroke incidence, independent of individual SES.
Four electronic databases and reference lists of included articles were searched, and corresponding authors were contacted to locate additional studies. A keyword search strategy included the 3 broad domains of neighborhood, SES, and stroke. Eight studies met our inclusion criteria (e.g., nSES as an exposure, individual SES as a covariate, and stroke incidence as an outcome). We coded study methodology and findings across the 8 studies.
The results provide evidence for the overall nSES and stroke incidence association in Sweden and Japan, but not within the United States. Findings were inconclusive when examining the nSES-stroke incidence association stratified by race. We found evidence for the mediating role of biological factors in the nSES-stroke incidence association.
Higher neighborhood disadvantage was found to be associated with higher stroke risk, but it was not significant in all the studies. The relationship between nSES and stroke risk within different racial groups in the United States was inconclusive. Inconsistencies may be driven by differences in covariate adjustment (e.g., individual-level sociodemographic characteristics and neighborhood-level racial composition). Additional research is needed to investigate potential intermediate and modifiable factors of the association between nSES and stroke incidence, which could serve as intervention points.
Vitamin D insufficiency is common in hospitalized patients. Recent evidence suggests that vitamin D may enhance the innate immune response by induction of cathelicidin (LL-37), an endogenous ...antimicrobial peptide produced by macrophages and neutrophils. Thus, the relationship between vitamin D status and LL-37 production may be of importance for host immunity, but little data is available on this subject, especially in the setting of human sepsis syndrome and other critical illness.
Plasma concentrations of 25-hydroxyvitamin D (25(OH)D), vitamin D binding protein (DBP) and LL-37 in critically ill adult subjects admitted to intensive care units (ICUs) with sepsis and without sepsis were compared to healthy controls.
Critically ill subjects had significantly lower plasma 25(OH)D concentrations compared to healthy controls. Mean plasma LL-37 levels were significantly lower in critically ill subjects compared to healthy controls. Vitamin D binding protein levels in plasma were significantly lower in critically ill subjects with sepsis compared to critically ill subjects without sepsis. There was a significant positive association between circulating 25(OH)D and LL-37 levels.
This study demonstrates an association between critical illness and lower 25(OH)D and DBP levels in critically ill patients as compared to healthy controls. It also establishes a positive association between vitamin D status and plasma LL-37, which suggests that systemic LL-37 levels may be regulated by vitamin D status. Optimal vitamin D status may be important for innate immunity especially in the setting of sepsis. Further invention studies to examine this association are warranted.
The high prevalence of hypertension among the US black population is a major contributor to disparities in life expectancy; however, the causes for higher incidence of hypertension among black adults ...are unknown.
To evaluate potential factors associated with higher risk of incident hypertension among black adults.
Prospective cohort study of black and white adults selected from a longitudinal cohort study of 30 239 participants as not having hypertension at baseline (2003-2007) and participating in a follow-up visit 9.4 years (median) later.
There were 12 clinical and social factors, including score for the Southern diet (range, -4.5 to 8.2; higher values reflect higher level of adherence to the dietary pattern), including higher fried and related food intake.
Incident hypertension (systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or use of antihypertensive medications) at the follow-up visit.
Of 6897 participants (mean SD age, 62 8 years; 26% were black adults; and 55% were women), 46% of black participants and 33% of white participants developed hypertension. Black men had an adjusted mean Southern diet score of 0.81 (95% CI, 0.72 to 0.90); white men, -0.26 (95% CI, -0.31 to -0.21); black women, 0.27 (95% CI, 0.20 to 0.33); and white women, -0.57 (95% CI, -0.61 to -0.54). The Southern diet score was significantly associated with incident hypertension for men (odds ratio OR, 1.16 per 1 SD 95% CI, 1.06 to 1.27; incidence of 32.4% at the 25th percentile and 36.1% at the 75th percentile; difference, 3.7% 95% CI, 1.4% to 6.2%) and women (OR, 1.17 per 1 SD 95% CI, 1.08 to 1.28; incidence of 31.0% at the 25th percentile and 34.8% at the 75th percentile; difference, 3.8% 95% CI, 1.5% to 5.8%). The Southern dietary pattern was the largest mediating factor for differences in the incidence of hypertension, accounting for 51.6% (95% CI, 18.8% to 84.4%) of the excess risk among black men and 29.2% (95% CI, 13.4% to 44.9%) of the excess risk among black women. Among black men, a higher dietary ratio of sodium to potassium and an education level of high school graduate or less each mediated 12.3% of the excess risk of incident hypertension. Among black women, higher body mass index mediated 18.3% of the excess risk; a larger waist, 15.2%; less adherence to the Dietary Approaches to Stop Hypertension diet, 11.2%; income level of $35 000 or less, 9.3%; higher dietary ratio of sodium to potassium, 6.8%; and an education level of high school graduate or less, 4.1%.
In a mediation analysis comparing incident hypertension among black adults vs white adults in the United States, key factors statistically mediating the racial difference for both men and women included Southern diet score, dietary ratio of sodium to potassium, and education level. Among women, waist circumference and body mass index also were key factors.