Faculty Bibliography

BACKGROUND:N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a cardiac biomarker used in the clinical management of heart failure. We sought to create updated reference intervals for NT-proBNP for healthy US children, adolescents, and adults. METHODS:We identified a population of healthy individuals using the 1999 to 2004 cycles of the National Health and Nutrition Examination Survey (NHANES). We measured serum NT-proBNP in 12 346 adults and 15 752 children and adolescents with the Elecsys NT-proBNP assay on the Roche e601 autoanalyzer. We compared 4 methods for reference interval calculation, and presented the final reference intervals using the robust method partitioned by age and sex categories. RESULTS:NT-proBNP values were available for 1949 healthy adults and 5250 healthy children and adolescents. NT-proBNP concentrations in males and females varied according to age, being higher in early childhood, relatively lower in late adolescence, and highest through middle age and older age. Females tended to have higher NT-proBNP concentrations compared to men from late adolescence until middle age. The upper reference limit, or 97.5th percentile, for 50 to 59 year-old men was 225 ng/L (90% CI: 158 to 236), and for 50 to 59 year-old women, 292 ng/L (90% CI: 242 to 348). CONCLUSIONS:Among healthy individuals, NT-proBNP concentrations varied greatly according age and sex. The reference intervals presented here should inform future clinical decision limits and suggest that age- and sex-specific intervals may be necessary to more precisely characterize risk.

BACKGROUND:Myocardial injury is an important pediatric diagnosis. Establishing normative data from a representative pediatric sample is vital to provide accurate upper reference limits (URLs) for defining myocardial injury using high-sensitivity cardiac troponin. METHODS:Among participants 1 to 18 years of age in the 1999-2004 National Health and Nutrition Examination Survey, we measured high-sensitivity troponin T using one assay (Roche) and high-sensitivity troponin I using 3 assays (Abbott, Siemens, and Ortho). In a strictly defined healthy subgroup, we estimated 97.5th and 99th percentile URLs for each assay using the recommended nonparametric method. RESULTS:Of 5695 pediatric participants, 4029 met criteria for the healthy subgroup (50% males; mean age 12.6 years). Our 99th percentile URL estimates for all 4 high-sensitivity troponin assays among children and adolescents were lower than the manufacturer-reported URLs (derived from adults). The 99th percentile URLs (95% CI) were 15 ng/L (95% CI, 12-17) for high-sensitivity troponin T, 16 ng/L (95% CI, 12-19) for high-sensitivity troponin I with the Abbott assay, 38 ng/L (95% CI, 25-46) for high-sensitivity troponin I with the Siemens assay, and 7 ng/L (95% CI, 5, 12) for high-sensitivity troponin I with the Ortho assay. The 95% CIs for age-, sex-, and race and ethnicity-specific 99th percentile URLs overlapped. However, the 97.5th percentile URL for each assay was measured with superior statistical precision (ie, tighter 95% CIs) and demonstrated differences by sex. For male compared with female children and adolescents, 97.5th percentile URLs were 11 ng/L (95% CI, 10-12) versus 6 ng/L (95% CI, 6-7) for high-sensitivity troponin T, 9 ng/L (95% CI, 7-10) versus 5 ng/L (95% CI, 4-6) for high-sensitivity troponin I with the Abbott assay, 21 ng/L (95% CI, 18-25) versus 11 ng/L (95% CI, 9-13) for high-sensitivity troponin I with the Siemens assay, and 4 ng/L (95% CI, 3-5) versus 2 ng/L (95% CI, 1-3) for high-sensitivity troponin I with the Ortho assay. In contrast to the 99th percentiles, the point estimates of 97.5th percentile pediatric URLs for high-sensitivity troponin were also much more stable to differences in the analytic approaches taken to estimate URLs. CONCLUSIONS:Because myocardial infarction is rare in children and adolescents, the use of statistically more precise and reliable sex-specific 97.5th percentile high-sensitivity troponin URLs might be considered to define pediatric myocardial injury.

BACKGROUND:Within healthy dietary patterns, manipulation of the proportion of macronutrient can reduce CVD risk. However, the biological pathways underlying healthy diet-disease associations are poorly understood. Using an untargeted, large-scale proteomic profiling, we aimed to (1) identify proteins mediating the association between healthy dietary patterns varying in the proportion of macronutrient and lipoproteins, and (2) validate the associations between diet-related proteins and lipoproteins in the Atherosclerosis Risk in Communities (ARIC) Study. METHODS:-transformed proteins in 3 between-diet comparisons using paired t-tests, examined the associations between diet-related proteins and lipoproteins using linear regression, and identified proteins mediating these associations using a causal mediation analysis. Levels of diet-related proteins and lipoprotein associations were validated in the ARIC study (n = 11,201) using multivariable linear regression models, adjusting for important confounders. RESULTS:Three between-diet comparisons identified 497 significantly different proteins (protein-rich vs. carbohydrate-rich = 18; unsaturated fat-rich vs. carbohydrate-rich = 335; protein-rich vs. unsaturated fat-rich dietary patterns = 398). Of these, 9 proteins [apolipoprotein M, afamin, collagen alpha-3(VI) chain, chitinase-3-like protein 1, inhibin beta A chain, palmitoleoyl-protein carboxylesterase NOTUM, cathelicidin antimicrobial peptide, guanylate-binding protein 2, COP9 signalosome complex subunit 7b] were positively associated with lipoproteins [high-density lipoprotein (HDL)-cholesterol (C) = 2; triglyceride = 5; non-HDL-C = 3; total cholesterol to HDL-C ratio = 1]. Another protein, sodium-coupled monocarboxylate transporter 1, was inversely associated with HDL-C and positively associated with total cholesterol to HDL-C ratio. The proportion of the association between diet and lipoproteins mediated by these 10 proteins ranged from 21 to 98%. All of the associations between diet-related proteins and lipoproteins were significant in the ARIC study, except for afamin. CONCLUSIONS:We identified proteins that mediate the association between healthy dietary patterns varying in macronutrients and lipoproteins in a randomized feeding study and an observational study. TRIAL REGISTRATION/BACKGROUND:NCT00051350 at clinicaltrials.gov.

IMPORTANCE:Mortality from cardiovascular disease (CVD) varies across communities and is associated with known structural and population health factors. Still, a population's well-being, including sense of purpose, social relationships, financial security, and relationship to community, may be an important target to improve cardiovascular health. OBJECTIVE:To examine the association of population level measures of well-being with rates of CVD mortality in the US. DESIGN, SETTING, AND PARTICIPANTS:This cross-sectional study linked data from the Gallup National Health and Well-Being Index (WBI) survey to county-level rates of CVD mortality from the Centers for Disease Control and Prevention Atlas of Heart Disease and Stroke. Participants were respondents of the WBI survey, which was conducted by Gallup with randomly selected adults aged 18 years or older from 2015 to 2017. Data were analyzed from August 2022 to May 2023. MAIN OUTCOMES AND MEASURES:The primary outcome was the county-level rate of total CVD mortality; secondary outcomes were mortality rates for stroke, heart failure, coronary heart disease, acute myocardial infarction, and total heart disease. The association of population well-being (measured using a modified version of the WBI) with CVD mortality was assessed, and an analysis of whether the association was modified by county structural factors (Area Deprivation Index [ADI], income inequality, and urbanicity) and population health factors (percentages of the adult population who had hypertension, diabetes, or obesity; were currently smoking; and were physically inactive) was conducted. Population WBI and its ability to mediate the association of structural factors associated with CVD using structural equation models was also assessed. RESULTS:Well-being surveys were completed by 514 971 individuals (mean [SD] age 54.0 [19.2] years; 251 691 [48.9%] women; 379 521 [76.0%] White respondents) living in 3228 counties. Mortality rates for CVD decreased from a mean of 499.7 (range, 174.2-974.7) deaths per 100 000 persons in counties with the lowest quintile of population well-being to 438.6 (range, 110.1-850.4) deaths per 100 000 persons in counties with the highest quintile of population well-being. Secondary outcomes showed similar patterns. In the unadjusted model, the effect size (SE) of WBI on CVD mortality was -15.5 (1.5; P < .001), or a decrease of 15 deaths per 100 000 persons for each 1-point increase of population well-being. After adjusting for structural factors and structural plus population health factors, the association was attenuated but still significant, with an effect size (SE) of -7.3 (1.6; P < .001); for each 1-point increase in well-being, the total cardiovascular death rate decreased by 7.3 deaths per 100 000 persons. Secondary outcomes showed similar patterns, with mortality due to coronary heart disease and heart failure being significant in fully adjusted models. In mediation analyses, associations of income inequality and ADI with CVD mortality were all partly mediated by the modified population WBI. CONCLUSIONS AND RELEVANCE:In this cross-sectional study assessing the association of well-being and cardiovascular outcomes, higher well-being, a measurable, modifiable, and meaningful outcome, was associated with lower CVD mortality, even after controlling for structural and cardiovascular-related population health factors, indicating that well-being may be a focus for advancing cardiovascular health.

IMPORTANCE:Black men have a higher risk of prostate cancer compared with White men, but Black adults are underrepresented in online content about prostate cancer. Across racial groups, the internet is a popular source of health information; Black adults are more likely to trust online health information, yet have more medical mistrust than White adults. OBJECTIVE:To evaluate the association between racial representation in online content about prostate cancer and trust in the content and identify factors that influence trust. DESIGN, SETTING, AND PARTICIPANTS:A randomized clinical trial was conducted from August 18, 2021, to January 7, 2022, consisting of a 1-time online survey. Participants included US men and women aged 40 years and older. Data were analyzed from January 2022 to June 2023. INTERVENTIONS:Participants were randomized to watch the same video script about either prostate cancer screening or clinical trials presented by 1 of 4 speakers: a Black physician, a Black patient, a White physician, or a White patient, followed by a questionnaire. MAIN OUTCOMES AND MEASURES:The primary outcome was a published scale for trust in the information. χ2 tests and multivariable logistic regression were used to compare trust according to the video's speaker and topic. RESULTS:Among 2904 participants, 1801 (62%) were men, and the median (IQR) age was 59 (47-69) years. Among 1703 Black adults, a greater proportion had high trust in videos with Black speakers vs White speakers (72.7% vs 64.3%; adjusted odds ratio [aOR], 1.62; 95% CI, 1.28-2.05; P < .001); less trust with patient vs physician presenter (64.6% vs 72.5%; aOR, 0.63; 95% CI, 0.49-0.80; P < .001) and about clinical trials vs screening (66.3% vs 70.7%; aOR, 0.78; 95% CI, 0.62-0.99; P = .04). Among White adults, a lower proportion had high trust in videos featuring a patient vs physician (72.0% vs 78.6%; aOR, 0.71; 95% CI, 0.54-0.95; P = .02) and clinical trials vs screening (71.4% vs 79.1%; aOR, 0.57; 95% CI, 0.42-0.76; P < .001), but no difference for Black vs White presenters (76.8% vs 73.7%; aOR, 1.11; 95% CI, 0.83-1.48; P = .49). CONCLUSIONS AND RELEVANCE:In this randomized clinical trial, prostate cancer information was considered more trustworthy when delivered by a physician, but racial concordance was significantly associated with trust only among Black adults. These results highlight the importance of physician participation and increasing racial diversity in public dissemination of health information and an ongoing need for public education about clinical trials. TRIAL REGISTRATION:ClinicalTrials.gov Identifier: NCT05886751.

BACKGROUND:With each succession along the surgical career pathway, from medical school to faculty, the percentage of those who identify as underrepresented in medicine (URiM) decreases. We sought to evaluate the demographic trend of surgical fellowship applicants, matriculants, and graduates over time. STUDY DESIGN:The Electronic Residency Application Service and the Graduate Medical Education Survey for general surgery fellowships in colorectal surgery, surgical oncology, pediatric surgery, thoracic surgery, and vascular surgery were retrospectively analyzed (2005 to 2020). The data were stratified by race and gender, descriptive statistics were performed, and time series were evaluated. Race/ethnicity groups included White, Asian, other, and URiM, which is defined as Black/African American, Hispanic/Latino(a), Alaskan or Hawaiian Native, and Native American. RESULTS:From 2005 to 2020, there were 5,357 Electronic Residency Application Service applicants, 4,559 matriculants, and 4,178 graduates to surgery fellowships. Whites, followed by Asians, represented the highest percentage of applicants (62.7% and 22.3%, respectively), matriculants (65.4% and 23.8% respectively), and graduates (65.4% and 24.0%, respectively). For URiMs, the applicants (13.4%), matriculants (9.1%), and graduates (9.1%) remained significantly low (p < 0.001). When stratified by both race and gender, only 4.6% of the applicants, 2.7% of matriculants, and 2.4% of graduates identified as both URiM and female compared to White female applicants (20.0%), matriculants (17.9%), and graduates (16.5%, p < 0.001). CONCLUSIONS:Significant disparities exist for URiMs in general surgery subspecialty fellowships. These results serve as a call to action to re-examine and improve the existing processes to increase the number of URiMs in the surgery subspecialty fellowship training pathway.

SIGNIFICANCE STATEMENT:Large discordances between eGFR on the basis of creatinine (eGFR cr ) or cystatin C (eGFR cys ) are common in clinical practice. However, which GFR estimating equation (eGFR cr , eGFR cys , or eGFR cr-cys ) is most accurate in these settings is not known. In this real-world study of 9404 concurrent measurements of creatinine, cystatin C, and iohexol clearance, all three equations performed similarly when eGFR cr and eGFR cys were similar (45% of cases). However, with large discordances (55% of cases), eGFR cr-cys was much more accurate than either alone. These findings were consistent among individuals with cardiovascular disease, heart failure, diabetes mellitus, liver disease, and cancer who have been underrepresented in research cohorts. Thus, when eGFR cr and eGFR cys are largely discordant in clinical practice, eGFR cr-cys is more accurate than eGFR cr or eGFR cys . BACKGROUND:Cystatin C is recommended as a confirmatory test to eGFR when more precise estimates are needed for clinical decision making. Although eGFR on the basis of both creatinine and cystatin (eGFR cr-cys ) is the most accurate estimate in research studies, it is uncertain whether this is true in real-world settings, particularly when there are large discordances between eGFR based on creatinine (eGFR cr ) and that based on cystatin C (eGFR cys ). METHODS:We included 6185 adults referred for measured GFR (mGFR) using plasma clearance of iohexol in Stockholm, Sweden, who had 9404 concurrent measurements of creatinine, cystatin C, and iohexol clearance. The performance of eGFR cr , eGFR cys , and eGFR cr-cys was assessed against mGFR with median bias, P30 , and correct classification of GFR categories. We stratified analyses within three categories: eGFR cys at least 20% lower than eGFR cr (eGFR cys <eGFR cr ), eGFR cys within 20% of eGFR cr (eGFR cys ≈eGFR cr ), and eGFR cys at least 20% higher than eGFR cr (eGFR cys >eGFR cr ). RESULTS:eGFR cr and eGFR cys were similar in 4226 (45%) samples, and among these samples all three estimating equations performed similarly. By contrast, eGFR cr-cys was much more accurate in cases of discordance. For example, when eGFR cys <eGFR cr (47% of samples), the median biases were 15.0 (overestimation), -8.5 (underestimation), and 0.8 ml/min per 1.73 m 2 for eGFR cr , eGFR cys , and eGFR cr-cys , respectively; P30 was 50%, 73%, and 84%, respectively; and correct classification was 38%, 45%, and 62%, respectively. When eGFR cys >eGFR cr (8% of samples), the median biases were -4.5, 8.4, and 1.4 ml/min per 1.73m 2 . The findings were consistent among individuals with cardiovascular disease, heart failure, diabetes mellitus, liver disease, and cancer. CONCLUSIONS:When eGFR cr and eGFR cys are highly discordant in clinical practice, eGFR cr-cys is more accurate than either eGFR cr or eGFR cys .

SIGNIFICANCE STATEMENT:Although gene expression changes have been characterized in human diabetic kidney disease (DKD), unbiased tissue proteomics information for this condition is lacking. The authors conducted an unbiased aptamer-based proteomic analysis of samples from patients with DKD and healthy controls, identifying proteins with levels that associate with kidney function (eGFR) or fibrosis, after adjusting for key covariates. Overall, tissue gene expression only modestly correlated with tissue protein levels. Kidney protein and RNA levels of matrix metalloproteinase 7 (MMP7) strongly correlated with fibrosis and with eGFR. Single-cell RNA sequencing indicated that kidney tubule cells are an important source of MMP7. Furthermore, plasma MMP7 levels predicted future kidney function decline. These findings identify kidney tissue MMP7 as a biomarker of fibrosis and blood MMP7 as a biomarker for future kidney function decline. BACKGROUND:Diabetic kidney disease (DKD) is responsible for close to half of all ESKD cases. Although unbiased gene expression changes have been extensively characterized in human kidney tissue samples, unbiased protein-level information is not available. METHODS:We collected human kidney samples from 23 individuals with DKD and ten healthy controls, gathered associated clinical and demographics information, and implemented histologic analysis. We performed unbiased proteomics using the SomaScan platform and quantified the level of 1305 proteins and analyzed gene expression levels by bulk RNA and single-cell RNA sequencing (scRNA-seq). We validated protein levels in a separate cohort of kidney tissue samples as well as in 11,030 blood samples. RESULTS:Globally, human kidney transcript and protein levels showed only modest correlation. Our analysis identified 14 proteins with kidney tissue levels that correlated with eGFR and found that the levels of 152 proteins correlated with interstitial fibrosis. Of the identified proteins, matrix metalloprotease 7 (MMP7) showed the strongest association with both fibrosis and eGFR. The correlation between tissue MMP7 protein expression and kidney function was validated in external datasets. The levels of MMP7 RNA correlated with fibrosis in the primary and validation datasets. Findings from scRNA-seq pointed to proximal tubules, connecting tubules, and principal cells as likely cellular sources of increased tissue MMP7 expression. Furthermore, plasma MMP7 levels correlated not only with kidney function but also associated with prospective kidney function decline. CONCLUSIONS:Our findings, which underscore the value of human kidney tissue proteomics analysis, identify kidney tissue MMP7 as a diagnostic marker of kidney fibrosis and blood MMP7 as a biomarker for future kidney function decline.