Recalibration of blood analytes over 25 years in the atherosclerosis risk in communities study: impact of recalibration on chronic kidney disease prevalence and incidence

APOL1 Kidney Risk Variants and Long-Term Kidney Function in Healthy Middle-Aged Black Individuals: The Atherosclerosis Risk in Communities (ARIC) Study

Rationale & Objective

The effect of apolipoprotein L1(APOL1) genotype on future risk of kidney disease among middle-aged individuals with good kidney function is not well established.

Study Design

Longitudinal cohort study.

Setting & Participants

In total, 5,886 healthy individuals (45-64 years old) enrolled in the Atherosclerosis Risk in Communities study with creatinine-based estimated glomerular filtration rate ≥ 80 mL/min who would be suitable kidney donors.

Exposures

Race and APOL1 genotype.

Outcomes

Creatinine- and cystatin C-based estimated glomerular filtration rate (eGFRcr-cys) using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) 2021 equation, urinary albumin-creatinine ratio (UACR), proportion with chronic kidney disease (CKD) 3a or worse, end-stage kidney disease (ESKD), and death.

Analytical Approach

Participants grouped based on race and APOL1 genotype. Compared eGFRcr-cys and UACR across groups. Multinomial logistic regression models were used compare odds of CKD. Kaplan-Meier survival curves were created to compare rates of ESKD and death at last follow-up.

Results

There were 5,075 Whites (86%), 701 Blacks carrying the low-risk APOL1 genotype (12%), and 110 Blacks carrying the high-risk APOL1 genotype (2%). The mean age at baseline was 53 ± 6 years. At 10 years, White participants had lower eGFRcr-cys than low-risk and high-risk groups (89 ± 16 vs 91 ± 16 and 92 ± 15 mL/min/1.73 m2, respectively; P < 0.001). At 25 years, White participants continued to have lower eGFRcr-cys than the low-risk group (70 ± 18 vs 72 ± 19 mL/min/1.73 m2; P < 0.001) but not compared with the high-risk APOL1 genotype (67±23 mL/min/1.73 m2). There was no difference in UACR among groups at 10 and 25 years (P = 0.87 and 0.91, respectively). The odds of developing CKD stage 3a or worse were not different between low-risk and high-risk APOL1 group in both unadjusted and adjusted models (P = 0.26 and P = 0.39, respectively). At last follow-up, <5% developed ESKD, and 45% of individuals either died or reached ESKD with no difference in outcomes between the groups.

Limitations

Low ascertainment because of death and long follow-up.

Conclusions

Among middle-aged individuals, APOL1 genotype does not appear to be a major driver of future risk of kidney disease.

Nonalcoholic Fatty Liver Disease and Longitudinal Change in Imaging and Plasma Biomarkers of Alzheimer Disease and Vascular Pathology

BACKGROUND AND OBJECTIVES

Prospective measures of plasma and cerebral MRI biomarkers of Alzheimer disease (AD) and vascular neuropathology provide an opportunity to investigate possible mechanisms linking liver disease and dementia. We aimed to quantify the association of midlife nonalcoholic fatty liver disease (NAFLD) with change in plasma and brain MRI biomarkers of AD and vascular neuropathology.

METHODS

We included participants from the Atherosclerosis Risk in Communities Study with brain MRI measurements of white matter hyperintensity (WMH) volume and temporal-parietal lobe cortical thickness meta region of interest (ROI) at up to 2 different visits, in 2011-13 and 2016-19, and plasma biomarkers of β-amyloid (Aβ)42:40, phosphorylated tau at threonine 181, and neurofilament light (NfL) were measured up to 3 times in 1993-95, 2011-13, and 2016-19. NAFLD was categorized using the fatty liver index in 1990-92. Multivariate linear regression was performed for associations between midlife NAFLD and change in plasma and brain MRI biomarkers of AD and vascular neuropathology. The primary models adjusted for demographics, Apolipoprotein E, alcohol use, and kidney function.

RESULTS

Among 1,706 participants (mean age 56 years, 62% female, 28% Black), midlife NAFLD vs no NAFLD was associated with greater late-life WMH volume (difference per SD 0.19, 95% CI 0.06-0.31) and faster late-life WMH increase over 6 years (difference in annual change, SD 0.28, 95% CI 0.05-0.51), suggesting accumulating vascular pathology. Midlife NAFLD vs no NAFLD was also associated with AD biomarkers in midlife (lower Aβ42:40 [SD -0.21, 95% CI -0.39 to -0.04] measured in 1993-95) and late life (lower Aβ42:40 [SD -0.13, 95% CI -0.23 to -0.03] and lower temporal-parietal lobe cortical thickness meta ROI [SD -0.16, 95% CI -0.28 to -0.05] measured in 2011-13). Although midlife NfL was lower in individuals with vs without midlife NAFLD, those with NAFLD exhibited a faster rate of NfL increase that accelerated over time.

DISCUSSION

Midlife NAFLD shows associations with AD and accumulating vascular pathology, revealing potential pathways linking liver function to dementia. Plasma biomarkers of neuropathology and neuronal injury may serve as easily measurable and dynamic indicators for monitoring the impacts of impaired liver function on brain health.

A polygenic risk score of atrial fibrillation improves prediction of lifetime risk for heart failure

AIMS

Heart failure (HF) has shared genetic architecture with its risk factors: atrial fibrillation (AF), body mass index (BMI), coronary heart disease (CHD), systolic blood pressure (SBP), and type 2 diabetes (T2D). We aim to assess the association and risk prediction performance of risk-factor polygenic risk scores (PRSs) for incident HF and its subtypes in bi-racial populations.

METHODS AND RESULTS

Five PRSs were constructed for AF, BMI, CHD, SBP, and T2D in White participants of the Atherosclerosis Risk in Communities (ARIC) study. The associations between PRSs and incident HF and its subtypes were assessed using Cox models, and the risk prediction performance of PRSs was assessed using C statistics. Replication was performed in the ARIC study Black and Cardiovascular Health Study (CHS) White participants. In 8624 ARIC study Whites, 1922 (31% cumulative incidence) HF cases developed over 30 years of follow-up. PRSs of AF, BMI, and CHD were associated with incident HF (P < 0.001), where PRSAF showed the strongest association [hazard ratio (HR): 1.47, 95% confidence interval (CI): 1.41-1.53]. Only the addition of PRSAF to the ARIC study HF risk equation improved C statistics for 10 year risk prediction from 0.812 to 0.829 (∆C: 0.017, 95% CI: 0.009-0.026). The PRSAF was associated with both incident HF with reduced ejection fraction (HR: 1.43, 95% CI: 1.27-1.60) and incident HF with preserved ejection fraction (HR: 1.46, 95% CI: 1.33-1.62). The associations between PRSAF and incident HF and its subtypes, as well as the improved risk prediction, were replicated in the ARIC study Blacks and the CHS Whites (P < 0.050). Protein analyses revealed that N-terminal pro-brain natriuretic peptide and other 98 proteins were associated with PRSAF.

CONCLUSIONS

The PRSAF was associated with incident HF and its subtypes and had significant incremental value over an established HF risk prediction equation.

Serum Metabolomic Markers of Protein-Rich Foods and Incident CKD: Results From the Atherosclerosis Risk in Communities Study

Rationale & Objective

While urine excretion of nitrogen estimates the total protein intake, biomarkers of specific dietary protein sources have been sparsely studied. Using untargeted metabolomics, this study aimed to identify serum metabolomic markers of 6 protein-rich foods and to examine whether dietary protein-related metabolites are associated with incident chronic kidney disease (CKD).

Study Design

Prospective cohort study.

Setting & Participants

A total of 3,726 participants from the Atherosclerosis Risk in Communities study without CKD at baseline.

Exposures

Dietary intake of 6 protein-rich foods (fish, nuts, legumes, red and processed meat, eggs, and poultry), serum metabolites.

Outcomes

Incident CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m2 with ≥25% estimated glomerular filtration rate decline relative to visit 1, hospitalization or death related to CKD, or end-stage kidney disease).

Analytical Approach

Multivariable linear regression models estimated cross-sectional associations between protein-rich foods and serum metabolites. C statistics assessed the ability of the metabolites to improve the discrimination of highest versus lower 3 quartiles of intake of protein-rich foods beyond covariates (demographics, clinical factors, health behaviors, and the intake of nonprotein food groups). Cox regression models identified prospective associations between protein-related metabolites and incident CKD.

Results

Thirty significant associations were identified between protein-rich foods and serum metabolites (fish, n = 8; nuts, n = 5; legumes, n = 0; red and processed meat, n = 5; eggs, n = 3; and poultry, n = 9). Metabolites collectively and significantly improved the discrimination of high intake of protein-rich foods compared with covariates alone (difference in C statistics = 0.033, 0.051, 0.003, 0.024, and 0.025 for fish, nuts, red and processed meat, eggs, and poultry-related metabolites, respectively; P < 1.00 × 10-16 for all). Dietary intake of fish was positively associated with 1-docosahexaenoylglycerophosphocholine (22:6n3), which was inversely associated with incident CKD (HR, 0.82; 95% CI, 0.75-0.89; P = 7.81 × 10-6).

Limitations

Residual confounding and sample-storage duration.

Conclusions

We identified candidate biomarkers of fish, nuts, red and processed meat, eggs, and poultry. A fish-related metabolite, 1-docosahexaenoylglycerophosphocholine (22:6n3), was associated with a lower risk of CKD.

Liver integrity and the risk of Alzheimer's disease and related dementias

INTRODUCTION

We examined midlife (1990-1992, mean age 57) and late-life (2011-2013, mean age 75) nonalcoholic fatty liver disease (NAFLD) and aminotransferase with incident dementia risk through 2019 in the Atherosclerosis Risk in Communities (ARIC) Study.

METHODS

We characterized NAFLD using the fatty liver index and fibrosis-4, and we categorized aminotransferase using the optimal equal-hazard ratio (HR) approach. We estimated HRs for incident dementia ascertained from multiple data sources.

RESULTS

Adjusted for demographics, alcohol consumption, and kidney function, individuals with low, intermediate, and high liver fibrosis in midlife (HRs: 1.45, 1.40, and 2.25, respectively), but not at older age, had higher dementia risks than individuals without fatty liver. A U-shaped association was observed for alanine aminotransferase with dementia risk, which was more pronounced in late-life assessment.

DISCUSSION

Our findings highlight dementia burden in high-prevalent NAFLD and the important feature of late-life aminotransaminase as a surrogate biomarker linking liver hypometabolism to dementia. Highlights Although evidence of liver involvement in dementia development has been documented in animal studies, the evidence in humans is limited. Midlife NAFLD raised dementia risk proportionate to severity. Late-life NAFLD was not associated with a high risk of dementia. Low alanine aminotransferase was associated with an elevated dementia risk, especially when measured in late life.

Omega-3 Polyunsaturated Fatty Acids are not associated with Peripheral Artery Disease in a Meta-Analysis from the Multi-Ethnic Study of Atherosclerosis and Atherosclerosis Risk in Communities Study Cohorts

BACKGROUND

Research suggests omega-3 polyunsaturated fatty acids (PUFAs) exert favorable effects on several biological processes involved in the development and progression of atherosclerotic cardiovascular disease (ASCVD). However, studies examining the relationship between omega-3 PUFAs and peripheral artery disease (PAD) are scarce.

OBJECTIVES

We evaluated the associations between omega-3 PUFAs and incident PAD in a meta-analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) and Atherosclerosis Risk in Communities (ARIC) study cohorts.

METHODS

Omega-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were measured at baseline for all MESA (n = 6495) and Minnesota ARIC participants (n = 3612). Incident clinical PAD events (MESA n = 106; ARIC n = 149) identified primarily through ICD discharge codes were assessed through follow-up of each cohort. Associations between omega-3 PUFAs (EPA, DHA, and EPA+DHA) and incident PAD were modeled in MESA and ARIC as quartiles and continuously using Cox proportional hazards regression, respectively. A fixed-effects meta-analysis was conducted to evaluate associations in the 2 cohorts combined.

RESULTS

In the fully adjusted model, in 10,107 participants, no significant associations were observed between EPA, DHA, or EPA+DHA, and incident PAD modeled as quartiles or continuously for either MESA or ARIC cohorts separately or in the meta-analysis after a follow-up of approximately 15 y.

CONCLUSION

This study is consistent with previous literature indicating that the beneficial effects of omega-3 PUFAs on the markers of ASCVD may not translate to a clinically meaningful decrease in PAD risk.

Prevalence of Elevated NT-proBNP and its Prognostic Value by Blood Pressure Treatment and Control

BACKGROUND

The prognostic utility of NT-proBNP in the setting of hypertension has not been well-characterized in the general US adult population.

METHODS

We measured NT-proBNP in stored blood samples collected from participants 1 year or older who participated in the 1999-2004 National Health and Nutrition Examination Survey. In adults 20 years or older without a history of cardiovascular disease, we assessed the prevalence of elevated NT-pro-BNP by blood pressure (BP) treatment and control categories. We examined the extent to which NT-proBNP identifies participants at higher risk for mortality across BP treatment and control categories.

RESULTS

Among US adults without CVD, the prevalence of elevated NT-proBNP (≥125 pg/ml) was 27.2% among those with untreated hypertension, 24.9% among those with treated controlled hypertension, and 43.3% among those with treated uncontrolled hypertension. Over a median follow-up of 17.3 years and after adjusting for demographic and clinical risk factors, US adults with treated controlled hypertension and elevated NT-proBNP had increased risk of all-cause mortality (HR 2.29, 95% CI 1.79, 2.95) and cardiovascular mortality (HR 3.83, 95% CI 2.34, 6.29), compared to adults without hypertension and with low levels of NT-proBNP (<125 pg/ml). Across all levels of SBP and irrespective of antihypertensive medication use, elevated NT-proBNP was associated with an increased risk of mortality, compared to low levels of NT-proBNP.

CONCLUSIONS

Among a general population of adults free of CVD, NT-proBNP can provide additional prognostic information within and across categories of BP. Measurement of NT-proBNP may have potential for clinical use to optimize hypertension treatment.

Body Composition Measures and N-terminal pro-B-type Natriuretic Peptide (NT-pro-BNP) in US Adults

BACKGROUND

The associations of N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) with dual energy x-ray absorptiometry (DEXA)-derived measures of body mass and composition are largely unknown.

METHODS

We included participants aged ≥20 years from the 1999-2004 National Health and Nutrition Examination Survey with NT-pro-BNP and DEXA-derived body composition (fat and lean mass) measures. We used linear and logistic regression to characterize the associations of measures of body mass and composition (body mass index [BMI], waist circumference [WC], fat mass, and lean mass) with NT-pro-BNP, adjusting for cardiovascular risk factors.

RESULTS

We conducted sex-specific analyses among 9134 adults without cardiovascular disease (mean age 44.4 years, 50.8% women, and 72% White adults). The adjusted mean NT-proBNP values were lowest in the highest quartiles of BMI, WC, fat mass, and lean mass. There were large adjusted absolute differences in NT-pro-BNP between the highest and lowest quartiles of DEXA-derived lean mass, -6.26 pg/mL (95% confidence interval [CI], -8.99 to -3.52) among men and -22.96 pg/mL (95% CI, -26.83 to -19.09) among women. Lean mass exhibited a strong inverse association with elevated NT-pro-BNP ≥ 81.4 pg/mL (highest quartile) - odds ratio (OR) 0.58 (95% CI, 0.39-0.86) in men and OR 0.59 (95% CI, 0.47-0.73) in women for highest lean mass quartile vs. lowest quartile. Further adjustment for fat mass, BMI, or WC did not appreciably alter the inverse association of lean mass with NT-pro-BNP.

CONCLUSIONS

In a national sample of US adults, lean mass was inversely associated with NT-pro-BNP.

Association of Long-term Change in N-Terminal Pro-B-Type Natriuretic Peptide With Incident Heart Failure and Death

Importance

Most studies, especially in primary prevention patients, have evaluated N-terminal B-type natriuretic peptide (NT-proBNP) at one time point. Evaluation of change in NT-proBNP may improve risk stratification for incident cardiovascular events.

Objective

To assess the association between change in NT-proBNP and risk for incident heart failure (HF) and death.

Design, Setting, and Participants

Participants were recruited from 4 US communities enrolled in the Atherosclerosis Risk in Community (ARIC) study. Individuals who attended ARIC visits 2 and 4 (approximately 6 years apart) with measurements of NT-proBNP and without prevalent HF were included. Assays of NT-proBNP were conducted between 2011 and 2013, and analysis took place between July 2021 and October 2022.

Exposures

The primary exposure variable was NT-proBNP change between visits 2 and 4, modeled as change categories (<125 pg/mL or ≥125 pg/mL) and as percent change.

Main Outcomes and Measures

The primary outcome measures were incident HF hospitalization and all-cause death. The association between changes in cardiovascular risk factors with change in NT-proBNP was further assessed.

Results

A total of 9776 individuals (mean [SD] age, 57.1 [5.7] years at visit 2; 5523 [56.5%] women) were included in the study. Compared with participants with NT-proBNP level less than 125 pg/mL at both visits, participants with NT-proBNP level of 125 pg/mL or higher at both visits had an increase in incident HF (adjusted hazard ratio [HR], 2.40 [95% CI, 2.00-2.88]) and mortality risk (HR, 1.68 [95% CI, 1.47-1.91). Participants with NT-proBNP levels of 125 pg/mL or higher at visit 2 and less than 125 pg/mL at visit 4 had similar risk for HF and death (HR, 1.01 [95% CI, 0.71-1.43]; HR, 0.79 [95% CI, 0.61-1.01]) compared with the group with NT-proBNP levels of less than 125 pg/mL at both visits. The percent change in NT-proBNP was positively associated with HF and death (HR, 1.06 [95% CI, 1.02-1.10]; HR, 1.05 [95% CI, 1.03-1.08] per 1-SD increase, respectively). Change in systolic blood pressure, low-density lipoprotein cholesterol, triglyceride level, body mass index, and estimated glomerular filtration rate were significantly associated with change in NT-proBNP.

Conclusions and Relevance

In this study, 6-year change in NT-proBNP reflected dynamic change in risk for HF events and death among community-dwelling adults without prevalent clinical HF. These results support the utility of serial NT-proBNP measurements to improve risk stratification of patients with pre-HF.

Association of Kidney Function Measures With Signs of Neurodegeneration and Small Vessel Disease on Brain Magnetic Resonance Imaging: The Atherosclerosis Risk in Communities (ARIC) Study

RATIONALE & OBJECTIVE

Chronic kidney disease (CKD) is a risk factor for cognitive decline, but evidence is limited on its etiology and morphological manifestation in the brain. We evaluated the association of estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (UACR) with structural brain abnormalities visible on magnetic resonance imaging (MRI). We also assessed whether this association was altered when different filtration markers were used to estimate GFR.

STUDY DESIGN

Cross-sectional study nested in a cohort study.

SETTING & PARTICIPANTS

1,527 participants in the Atherosclerosis Risk in Communities (ARIC) Study.

PREDICTORS

Log(UACR) and eGFR based on cystatin C, creatinine, cystatin C and creatinine in combination, or β2-microglobulin (B2M).

OUTCOMES

Brain volume reduction, infarcts, microhemorrhages, white matter lesions.

ANALYTICAL APPROACH

Multivariable linear and logistic regression models fit separately for each predictor based on a 1-IQR difference in the predictor value.

RESULTS

Each 1-IQR lower eGFR was associated with reduced cortex volume (regression coefficient: -0.07 [95% CI, -0.12 to-0.02]), greater white matter hyperintensity volume (logarithmically transformed; regression coefficient: 0.07 [95% CI, 0.01-0.15]), and lower white matter fractional anisotropy (regression coefficient: -0.08 [95% CI, -0.17 to-0.01]). The results were similar when eGFR was estimated with different equations based on cystatin C, creatinine, a combination of cystatin C and creatinine, or B2M. Higher log(UACR) was similarly associated with these outcomes as well as brain infarcts and microhemorrhages (odds ratios per 1-IQR-fold greater UACR of 1.31 [95% CI, 1.13-1.52] and 1.30 [95% CI, 1.12-1.51], respectively). The degree to which brain volume was lower in regions usually susceptible to Alzheimer disease and LATE (limbic-predominant age-related TDP-43 [Tar DNA binding protein 43] encephalopathy) was similar to that seen in the rest of the cortex.

LIMITATIONS

No inference about longitudinal effects due to cross-sectional design.

CONCLUSIONS

We found eGFR and UACR are associated with structural brain damage across different domains of etiology, and eGFR- and UACR-related brain atrophy is not selective for regions typically affected by Alzheimer disease and LATE. Hence, Alzheimer disease or LATE may not be leading contributors to neurodegeneration associated with CKD.

Plasma Protein Biomarkers of Healthy Dietary Patterns: Results from the Atherosclerosis Risk in Communities Study and the Framingham Heart Study

BACKGROUND

Molecular mechanisms underlying the benefits of healthy dietary patterns are poorly understood. Identifying protein biomarkers of dietary patterns can contribute to characterizing biological pathways influenced by food intake.

OBJECTIVES

This study aimed to identify protein biomarkers associated with four indexes of healthy dietary patterns: Healthy Eating Index-2015 (HEI-2015); Alternative Healthy Eating Index-2010 (AHEI-2010); DASH diet; and alternate Mediterranean Diet (aMED).

METHODS

Analyses were conducted on 10,490 Black and White men and women aged 49-73 y from the ARIC study at visit 3 (1993-1995). Dietary intake data were collected using a food frequency questionnaire, and plasma proteins were quantified using an aptamer-based proteomics assay. Multivariable linear regression models were used to examine the association between 4955 proteins and dietary patterns. We performed pathway overrepresentation analysis for diet-related proteins. An independent study population from the Framingham Heart Study was used for replication analyses.

RESULTS

In the multivariable-adjusted models, 282 out of 4955 proteins (5.7%) were significantly associated with at least one dietary pattern (HEI-2015: 137; AHEI-2010: 72; DASH: 254; aMED: 35; P value < 0.05/4955 = 1.01 × 10-5). There were 148 proteins that were associated with only one dietary pattern (HEI-2015: 22; AHEI-2010: 5; DASH: 121; aMED: 0), and 20 proteins were associated with all four dietary patterns. Five unique biological pathways were significantly enriched by diet-related proteins. Seven out of 20 proteins associated with all dietary patterns in the ARIC study were available for replication analyses, and 6 out of these 7 proteins were consistent in direction and significantly associated with at least 1 dietary pattern in the Framingham Heart Study (HEI-2015: 2; AHEI-2010: 4; DASH: 6; aMED: 4; P value < 0.05/7 = 7.14 × 10-3).

CONCLUSIONS

A large-scale proteomic analysis identified plasma protein biomarkers that are representative of healthy dietary patterns among middle-aged and older US adult population. These protein biomarkers may be useful objective indicators of healthy dietary patterns.

The performance of glycated albumin as a biomarker of hyperglycemia and cardiometabolic risk in children and adolescents in the United States

OBJECTIVE

Diabetes and prediabetes are growing concerns among US youth. Fasting glucose (FG) and HbA1c are standard diabetes screening tests, but HbA1c may be unreliable in some settings and fasting is burdensome in children. Glycated albumin (GA) is a non-fasting test that was recently cleared for clinical use in the United States, but studies in youth without diabetes are limited.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional analysis in 6826 youth without diabetes aged 8-19 years in the 1999-2004 National Health and Nutrition Examination Survey. We evaluated the associations of GA with HbA1c, FG, and cardiometabolic risk factors.

RESULTS

GA was poorly correlated with HbA1c (ρ = 0.074) and FG (ρ = -0.047) and was negatively associated with body mass index (BMI) and cardiometabolic risk factors. Compared to youth in the highest tertile of GA (≥13.5%), those in the lowest GA tertile (<12.4%) had a higher prevalence of obesity (29.9% vs. 7.6%), low high-density lipoprotein cholesterol (29.7% vs. 16.5%), and hypertensive blood pressure (4.0% vs. 2.7%). These inverse associations persisted after adjustment for age, sex, race/ethnicity, serum albumin, and C-reactive protein.

CONCLUSIONS

GA was poorly correlated with traditional markers of hyperglycemia in youth without diabetes. Counterintuitively, there was a negative association between GA and BMI. Among youth without diabetes, GA does not identify youth at high cardiometabolic risk, and it does not appear to be an appropriate biomarker for screening of hyperglycemia.

Polygenic Risk Scores for Kidney Function and Their Associations with Circulating Proteome, and Incident Kidney Diseases

BACKGROUND

Genome-wide association studies (GWAS) have revealed numerous loci for kidney function (eGFR). The relationship between polygenic predictors of eGFR, risk of incident adverse kidney outcomes, and the plasma proteome is not known.

METHODS

We developed a genome-wide polygenic risk score (PRS) for eGFR by applying the LDpred algorithm to summary statistics generated from a multiethnic meta-analysis of CKDGen Consortium GWAS ( n =765,348) and UK Biobank GWAS (90% of the cohort; n =451,508), followed by best-parameter selection using the remaining 10% of UK Biobank data ( n =45,158). We then tested the association of the PRS in the Atherosclerosis Risk in Communities (ARIC) study ( n =8866) with incident CKD, ESKD, kidney failure, and AKI. We also examined associations between the PRS and 4877 plasma proteins measured at middle age and older adulthood and evaluated mediation of PRS associations by eGFR.

RESULTS

The developed PRS showed a significant association with all outcomes. Hazard ratios per 1 SD lower PRS ranged from 1.06 (95% CI, 1.01 to 1.11) to 1.33 (95% CI, 1.28 to 1.37). The PRS was significantly associated with 132 proteins at both time points. The strongest associations were with cystatin C, collagen α -1(XV) chain, and desmocollin-2. Most proteins were higher at lower kidney function, except for five proteins, including testican-2. Most correlations of the genetic PRS with proteins were mediated by eGFR.

CONCLUSIONS

A PRS for eGFR is now sufficiently strong to capture risk for a spectrum of incident kidney diseases and broadly influences the plasma proteome, primarily mediated by eGFR.

Mid- to Late-Life Inflammation and Risk of Cardiac Dysfunction, HFpEF and HFrEF in Late Life

BACKGROUND

Epidemiologic data supporting the association of accumulated inflammation from mid- to late life with late-life risk of cardiac dysfunction and heart failure (HF) is limited.

METHODS AND RESULTS

Among 4011 participants in the Atherosclerosis Risk in Communities study who were free of prevalent cardiovascular disease at study Visit 5, accumulated inflammation was defined as time-averaged high-sensitivity c-reactive protein (hsCRP) over 3 visits spanning 1990 to 2013. Associations with left ventricular (LV) function at Visit 5 and with incident adjudicated HF post Visit 5 were assessed using linear and Cox regression, adjusting for demographics and comorbidities. Higher accumulated hsCRP was associated with greater LV mass index, lower e', higher E/e', and higher adjusting for demographics (all P ≤0.01), but only with higher pulmonary artery systolic pressure after adjustment for comorbidities (P = 0.024). At 5.3 ± 1.2 year follow-up, higher accumulated hsCRP was associated with greater risk of incident HF (HR 1.31 [95% CI 1.18-1.47], P < 0.001), HFrEF (1.26 [1.05-1.52], P = 0.01), and HFpEF (1.30 [1.11-1.53], P = 0.001) in demographic-adjusted models, but not after adjustment for comorbidities (all P > 0.10). Only Visit 5 hsCRP remained associated with incident HF (1.12 [1.02-1.24], P = 0.02) after full adjustment.

CONCLUSIONS

Greater accumulated inflammation is associated with worse LV function and heightened HF risk in late-life. These relationships are attenuated after adjusting for HF risk factors.

6-year change in high sensitivity cardiac troponin T and the risk of atrial fibrillation in the Atherosclerosis Risk in Communities cohort

BACKGROUND

Circulating high sensitivity cardiac troponin T (hs-cTnT) is associated with incidence of atrial fibrillation (AF), but the association of changes in hs-cTnT over time on incident AF has not been explored.

HYPOTHESIS

Six-year increase in circulating hs-cTnT will be associated with increased risk of AF and will contribute to improved prediction of incident AF.

METHODS

We conducted a prospective cohort analysis of 8431 participants from the Atherosclerosis Risk in Communities (ARIC) study. hs-cTnT change was categorized at visit 2 and 4 as undetectable (<5 ng/L), detectable (≥5 ng/L, <14 ng/L), or elevated (≥14 ng/L). We used Cox regression to examine the association between the combination of hs-cTnT categories at two visits and incident AF. We also assessed the impact of adding absolute hs-cTnT change on risk discrimination for AF by C-statistics and net reclassification improvement (NRI).

RESULTS

Over a mean follow-up of 16.5 years, 1629 incident AF cases were diagnosed. Among participants with undetectable hs-cTnT at visit 2, the multivariable HR of AF was 1.28 (95% CI 1.12-1.48) among those with detectable or elevated hs-cTnT at visit 4 compared to those in which hs-cTnT remained undetectable. Among those with detectable hs-cTnT at visit 2, compared to those who remained in the detectable hs-cTnT group, reduction to undetectable at visit 4 was associated with lower risk of AF (HR 0.74, 95% CI 0.59-0.94), while increment to elevated was associated with higher AF risk (HR 1.30, 95% CI 1.01-1.68). Adding hs-cTnT change to our main model with baseline hs-cTnT did not result in significant improvement in the C-statistic or substantial NRI.

CONCLUSION

Six-year increase in circulating hs-cTnT was associated with elevated risk of incident AF.

Higher Ultra-Processed Food Consumption Is Associated with Increased Risk of Incident Coronary Artery Disease in the Atherosclerosis Risk in Communities Study

BACKGROUND

Higher ultra-processed food intake has been linked with several cardiometabolic and cardiovascular diseases. However, prospective evidence from US populations remains scarce.

OBJECTIVES

To test the hypothesis that higher intake of ultra-processed foods is associated with higher risk of coronary artery disease.

METHODS

A total of 13,548 adults aged 45-65 y from the Atherosclerosis Risk in Communities study were included in the analytic sample. Dietary intake data were collected through a 66-item FFQ. Ultra-processed foods were defined using the NOVA classification, and the level of intake (servings/d) was calculated for each participant and divided into quartiles. We used Cox proportional hazards models and restricted cubic splines to assess the association between quartiles of ultra-processed food intake and incident coronary artery disease.

RESULTS

There were 2006 incident coronary artery disease cases documented over a median follow-up of 27 y. Incidence rates were higher in the highest quartile of ultra-processed food intake (70.8 per 10,000 person-y; 95% CI: 65.1, 77.1) compared with the lowest quartile (59.3 per 10,000 person-y; 95% CI: 54.1, 65.0). Participants in the highest compared with lowest quartile of ultra-processed food intake had a 19% higher risk of coronary artery disease (HR: 1.19; 95% CI: 1.05, 1.35) after adjusting for sociodemographic factors and health behaviors. An approximately linear relation was observed between ultra-processed food intake and risk of coronary artery disease.

CONCLUSIONS

Higher ultra-processed food intake was associated with a higher risk of coronary artery disease among middle-aged US adults. Further prospective studies are needed to confirm these findings and to investigate the mechanisms by which ultra-processed foods may affect health.

Preparing Laboratories for Interconnected Health Care

In an increasingly interconnected health care system, laboratory medicine can facilitate diagnosis and treatment of patients effectively. This article describes necessary changes and points to potential challenges on a technical, content, and organizational level. As a technical precondition, electronic laboratory reports have to become machine-readable and interpretable. Terminologies such as Logical Observation Identifiers Names and Codes (LOINC), Nomenclature for Properties and Units (NPU), Unified Code for Units of Measure (UCUM), and SNOMED-CT can lead to the necessary semantic interoperability. Even if only single “atomized” results of the whole report are extracted, the necessary information for correct interpretation must be available. Therefore, interpretive comments, e.g., concerns about an increased measurement uncertainty must be electronically attached to every affected measurement result. Standardization of laboratory analyses with traceable standards and reference materials will enable knowledge transfer and safe interpretation of laboratory analyses from multiple laboratories. In an interconnected health care system, laboratories should strive to transform themselves into a data hub that not only receives samples but also extensive information about the patient. On that basis, they can return measurement results enriched with high-quality interpretive comments tailored to the individual patient and unlock the full potential of laboratory medicine.

Six-year changes in N-terminal pro-brain natriuretic peptide and changes in weight and risk of obesity

OBJECTIVE

The aim of this study was to study the prospective association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and changes in weight and obesity risk in a community-based population.

METHODS

Data from 9,681 participants from the Atherosclerosis Risk in Communities Study were analyzed at two time points 6 years apart. Among people without obesity at baseline, multivariable logistic regression models were used to examine the association between baseline levels of NT-proBNP and incident obesity. A multivariable linear regression model was used to examine the association between changes in NT-proBNP (visit 2 serum and visit 4 plasma samples) and changes in weight.

RESULTS

The prevalence of obesity increased from 28% to 35% in the 6-year follow-up period. Compared with individuals in the highest NT-proBNP quartile, those in the lowest were more likely to have obesity at baseline (odds ratio 1.25; 95% CI: 1.08-1.45) and, among people who did not have obesity at baseline, were more likely to develop obesity at follow-up (odds ratio 1.35; 95% CI: 1.07-1.69). Changes in NT-proBNP were inversely associated with weight change.

CONCLUSIONS

In this prospective study, lower levels of NT-proBNP were associated with higher risk of obesity, and changes in NT-proBNP were inversely associated with changes in weight. This suggests that natriuretic peptides or their pathways may be potential targets in the treatment of obesity.

Silent Myocardial Infarction and Long-Term Risk of Frailty: The Atherosclerosis Risk in Communities Study

Background

Silent myocardial infarction (SMI) accounts for more than half of all MIs, and common risk factors and pathophysiological pathways coexist between SMI and frailty. The risk of frailty among patients with SMI is not well established. This study aimed to examine the association between SMI and frailty.

Methods and Results

This analysis included data from the Atherosclerosis Risk in Communities study. Patients without MI at baseline were eligible for inclusion. SMI was defined as electrocardiographic evidence of MI without clinical MI (CMI) after the baseline and until the fourth visit. Frailty was assessed during the fifth visit. A total of 4953 participants were included with an average age of 52.2±5.1 years. Among these participants, 2.7% (n=135) developed SMI, and 2.9% (n=146) developed CMI. After a median follow-up time of 14.7 (14.0–15.3) years, 6.7% (n=336) of the participants developed frailty. Patients with SMI and CMI were significantly more likely to become frail than those without MI (15.6% vs 6.2%, P<0.001 and 16.4% vs 6.2%, P<0.001, respectively). After adjusting for confounders, SMI and CMI were found to be independent predictors of frailty (odds ratio [OR]=2.243, 95% confidence interval [CI]=1.307–3.850, P=0.003 and OR=2.164, 95% CI=1.259–3.721, P=0.005, respectively). The association was consistent among the subgroups of age, sex, race, diabetes, and hypertension.

Conclusion

In conclusion, both SMI and CMI were found to be associated with a higher risk of frailty. Future studies are needed to confirm the beneficial effects of screening for SMI as well as to implement standardized preventive treatment to reduce the risk of frailty.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT00005131.

Association of arterial stiffness with incident atrial fibrillation: a cohort study

Background

Stiff arteries increase left ventricular (LV) end-systolic workload, leading over time to left atrial and ventricular remodeling, and providing the substrate for atrial fibrillation (AF) development. We investigated if carotid femoral pulse wave velocity (cfPWV), a measure of central arterial stiffness, is associated with incident AF.

Methods

In 20112013, cfPWV was measured in 3882 participants of the Atherosclerosis Risk in Communities Cohort Study (ARIC) without prevalent AF. Participants were followed through 2017 for the incidence of AF. Individuals were categorized in cfPWV quartiles based on visit measurements. Multivariable Cox regression models were used to evaluate the association of cfPWV with incident AF.

Results

Mean age was 75years (SD 5), 60% were female and 20% were African American. Over a median follow-up of 5.5years we identified 331 incident cases of AF. cfPWV demonstrated U-shaped associations with AF risk. In models adjusted for age, race, center, sex, education levels, and hemodynamic and clinical factors, hazard ratios (HR) of AF for participants in the first, third and fourth quartiles were 1.49 (95% CI 1.06, 2.10), 1.59 (1.14, 2.10), and 1.56(1.10, 2.19), respectively, compared to those in the second quartile.

Conclusion

Among community-dwelling older adults, low and high central arterial stiffness is associated with AF risk.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02057-8.

Evaluating chronic kidney disease in rural South Africa: comparing estimated glomerular filtration rate using point-of-care creatinine to iohexol measured GFR

OBJECTIVES

The prevalence of chronic kidney disease is rising rapidly in low- and middle-income countries. Serum creatinine and estimation of glomerular filtration rate (GFR) are critical diagnostic tools, yet access to centralised laboratory services remains limited in primary care resource-limited settings. The aim of this study was to evaluate point-of-care (POC) technologies for serum creatinine measurement and to compare their performance to a gold standard measurement using iohexol measured GFR (mGFR).

METHODS

POC creatinine was measured using iSTAT^® and StatSensor^® devices in capillary and venous whole blood, and laboratory creatinine was measured using the compensated kinetic Jaffe method in 670 participants from a rural area in South Africa. GFR estimating equations Chronic Kidney Disease Epidemiology Collaboration and Modification of Diet in Renal Disease (CKD-EPI and MDRD) for POC and laboratory creatinine were compared to iohexol mGFR.

RESULTS

Calculated GFR for laboratory and POC creatinine measurements overestimated GFR (positive bias of 1.9-34.1 mL/min/1.73 m²). However, all POC devices had less positive bias than the laboratory Jaffe method (1.9-14.7 vs. 34.1 for MDRD, and 8.4-19.9 vs. 28.6 for CKD-EPI). Accuracy within 30% of mGFR ranged from 0.56 to 0.72 for POC devices and from 0.36 to 0.43 for the laboratory Jaffe method. POC devices showed wider imprecision with coefficients of variation ranging from 4.6 to 10.2% compared to 3.5% for the laboratory Jaffe method.

CONCLUSIONS

POC estimated GFR (eGFR) showed improved performance over laboratory Jaffe eGFR, however POC devices suffered from imprecision and large bias. The laboratory Jaffe method performed poorly, highlighting the need for laboratories to move to enzymatic methods to measure creatinine.

Association Between Midlife Obesity and Kidney Function Trajectories: The Atherosclerosis Risk in Communities (ARIC) Study

RATIONALE & OBJECTIVE

Obesity has been related to risk for chronic kidney disease. However, the associations of different measures of midlife obesity with long-term kidney function trajectories and whether they differ by sex and race are unknown.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

13,496 participants from the Atherosclerosis Risk in Communities (ARIC) Study.

PREDICTORS

Midlife obesity status as measured by body mass index (BMI), waist-to-hip ratio, and predicted percent fat at baseline.

OUTCOMES

Estimated glomerular filtration rate (eGFR) calculated using serum creatinine level measured at 5 study visits, and incident kidney failure with replacement therapy (KFRT).

ANALYTICAL APPROACH

Mixed models with random intercepts and random slopes for eGFR. Cox proportional hazards models for KFRT.

RESULTS

Baseline mean age was 54 years, median eGFR was 103mL/min/1.73m2, and median BMI was 27kg/m2. Over 30 years of follow-up, midlife obesity measures were associated with eGFR decline in White and Black women but not consistently in men. Adjusted for age, center, smoking, and coronary heart disease, the differences in eGFR slope per 1-SD higher BMI, waist-to-hip ratio, and predicted percent fat were 0.09 (95% CI, -0.18 to 0.36), -0.25 (95% CI, -0.50 to 0.01), and-0.14 (95% CI, -0.41 to 0.13) mL/min/1.73m2 per decade for White men; -0.91 (95% CI, -1.15 to-0.67), -0.82 (95% CI, -1.06 to-0.58), and-1.02 (95% CI, -1.26 to-0.78) mL/min/1.73m2 per decade for White women; -0.70 (95% CI, -1.54 to 0.14), -1.60 (95% CI, -2.42 to-0.78), and-1.24 (95% CI, -2.08 to-0.40) mL/min/1.73m2 per decade for Black men; and-1.24 (95% CI, -2.08 to-0.40), -1.50 (95% CI, -2.05 to-0.95), and-1.43 (95% CI, -2.00 to-0.86) mL/min/1.73m2 per decade for Black women. Obesity indicators were independently associated with risk for KFRT for all sex-race groups except White men.

LIMITATIONS

Loss to follow-up during 3 decades of follow-up with 5 eGFR assessments.

CONCLUSIONS

Obesity status is a risk factor for future decline in kidney function and development of KFRT in Black and White women, with less consistent associations among men.

Association Between Midlife Physical Activity and Incident Kidney Disease: The Atherosclerosis Risk in Communities (ARIC) Study

RATIONALE & OBJECTIVE

Physical activity is associated with lower risk for cardiovascular disease, diabetes, and hypertension, which have shared risk factor profiles with chronic kidney disease (CKD). However, there are conflicting findings regarding the relationship between physical activity and CKD. The objective was to evaluate the association between physical activity and CKD development over long-term follow-up using the Atherosclerosis Risk in Communities (ARIC) Study.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

14,537 participants aged 45 to 64 years.

PREDICTORS

Baseline physical activity status was assessed using the modified Baecke Physical Activity Questionnaire at visit 1 (1987-1989) and categorized according to the 2018 Physical Activity Guidelines for Americans to group participants as inactive, insufficiently active, active, and highly active.

OUTCOMES

Incident CKD defined as estimated glomerular filtration rate (eGFR)<60mL/min/1.73m2 at follow-up and≥25% decline in eGFR relative to baseline, CKD-related hospitalization or death, or initiation of kidney replacement therapy.

ANALYTICAL APPROACH

Cox proportional hazards regression.

RESULTS

At baseline, 37.8%, 24.2%, 22.7%, and 15.3% of participants were classified as inactive, insufficiently active, active, and highly active, respectively. During a median follow-up of 24 years, 33.2% of participants developed CKD. After adjusting for age, sex, race-center, education, smoking status, diet quality, diabetes, coronary heart disease, hypertension, antihypertensive medication, body mass index, and baseline eGFR, higher categories of physical activity were associated with lower risk for CKD compared with the inactive group (HRs for insufficiently active, 0.95 [95% CI, 0.88-1.02]; active, 0.93 [95% CI, 0.86-1.01]; highly active, 0.89 [95% CI, 0.81-0.97]; P for trend = 0.007).

LIMITATIONS

Observational design and self-reported physical activity that was based on leisure time activity only. Due to low numbers, participants who were not Black or White were excluded.

CONCLUSIONS

Highly active participants had lower risk for developing CKD compared with inactive participants.

Albuminuria and Estimated GFR as Risk Factors for Dementia in Midlife and Older Age: Findings From the ARIC Study

RATIONALE & OBJECTIVE

Evidence is limited on how estimated glomerular filtration rate (eGFR) and urinary albumin-creatinine ratio (UACR) relate to dementia at different ages. We evaluated eGFR and UACR in midlife and older age as risk factors for dementia. Additionally, we assessed whether the association between eGFR and dementia is altered when cystatin C and β2-microglobulin (B2M) levels are used for GFR estimation.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Two baselines from the Atherosclerosis Risk in Communities (ARIC) Study were used: visit 4 (1996-1998), including 9,967 participants 54 to 74 years old, and visit 5 (2011-2013), including 4,626 participants 70 to 90 years old. Participants were followed up until 2017.

PREDICTORS

Log(UACR); eGFR based on creatinine, cystatin C, creatinine and cystatin C, or B2M levels (denoted as eGFRcr, eGFRcys, eGFRcr-cys, and eGFRB2M).

OUTCOME

Incident dementia.

ANALYTICAL APPROACH

Multivariable Cox proportional hazards regression models fit separately for each of the 5 predictors and based on a change in the predictor equivalent to the interquartile range for that predictor at visit 4 (IQRV4). eGFR models were adjusted for log(UACR) and log(UACR) models were adjusted for eGFRcys.

RESULTS

We observed 1,821 dementia cases after visit 4 and 438 cases after visit 5. Dementia risk increased with higher albuminuria levels (HRs per IQRV4 [equivalent to 4.2-fold greater log albuminuria] of 1.15 [95% CI, 1.09-1.21] after visit 4 and 1.27 [95% CI, 1.13-1.42] after visit 5). An association with lower eGFR was seen for only eGFRcys (HRs per IQRV4 [equivalent to 24.3mL/min/1.73m2 lesser eGFRcys] of 1.12 [95% CI, 1.04-1.21] after visit 4 and 1.30 [95% CI, 1.12-1.52] after visit 5) and eGFRB2M (HRs per IQRV4 [equivalent to 18.3mL/min/1.73m2 lesser eGFRB2M] of 1.15 [95% CI, 1.07-1.23] after visit 4 and 1.34 [95% CI, 1.17-1.55] after visit 5). Differences between these associations in midlife and older age were not statistically significant.

LIMITATIONS

Changes in potentially time-varying covariates were not measured. Dementia was not subclassified by cause.

CONCLUSIONS

Albuminuria was consistently associated with dementia incidence. Lower eGFR based on cystatin C or B2M, but not creatinine, levels was also associated with dementia. Risk associations were similar when kidney measures were assessed at midlife and older age.

Long-Term Longitudinal Stability of Kidney Filtration Marker Measurements: Implications for Epidemiological Studies and Clinical Care

BACKGROUND

Establishment and improvement of glomerular filtration rate estimating equations requires accurate and precise laboratory measurement procedures (MPs) for filtration markers. The Advanced Research and Diagnostic Laboratory (ARDL) at the University of Minnesota, which has served as the central laboratory for the Chronic Kidney Disease Epidemiology Collaboration since 2009, has implemented several quality assurance measures to monitor the accuracy and stability of filtration marker assays over time.

METHODS

To assess longitudinal stability for filtration marker assays, a 40-sample calibration panel was created using pooled serum, divided into multiple frozen aliquots stored at -80 °C. ARDL monitored 4 markers-creatinine, cystatin C, beta-2-microglobulin (B2M) and beta-trace protein-measuring 15 calibration panel aliquots from 2009 to 2019. Initial target values were established using the mean of the first 3 measurements performed in 2009-10, and differences from target were monitored over time. New MPs for cystatin C and B2M were added in 2012, with target values established using the first measurement.

RESULTS

The mean percentage difference from mean target values across time was <2% for all original MPs (-0.59% for creatinine; -0.94% for cystatin C; -0.82% for B2M; 1.24% for beta-trace protein).

CONCLUSIONS

Close monitoring of filtration marker trends with a calibration panel at ARDL demonstrates remarkable long-term stability of the MPs. Routine use of a calibration panel for both research studies and clinical care is recommended for filtration markers where longitudinal monitoring is important to detect analytical biases, which can mask or confound true clinical trends in patients.

MicroRNA-151 Attenuates Apoptosis of Endothelial Cells Induced by Oxidized Low-density Lipoprotein by Targeting Interleukin-17A (IL-17A)

Apoptosis of endothelial cells plays an important role in atherosclerosis (AS). MicroRNAs (miRNAs) have been confirmed to participate in the process of endothelial cell apoptosis. The main purpose of this study was to investigate the mechanism of miR-151 and interleukin-17A (IL-17A) in apoptosis of atherosclerotic endothelial cells. The expression levels of miR-151 in human aortic endothelial cells (HAEC) after Ox-LDL treatment were detected by qRT-PCR. The expression levels of IL-17A were detected by qRT-PCR and Western blot. The effects of miR-151 and IL-17A on the apoptosis rate were detected by flow cytometry. The relationship between miR-151 and IL-17A was assessed by bioinformatics analysis and luciferase assay. The expression levels of miR-151 in HAEC after Ox-LDL treatment were reduced, and the expression of IL-17A was upregulated. MiR-151 and si-IL-17A inhibited the apoptosis rate of aortic endothelial cells treated by Ox-LDL. MiR-151 and si-IL-17A reduced the expression levels of c-caspase-9, c-caspase-3, and BAX proteins in Ox-LDL-treated HAEC and increased the expression levels of Bcl-2. MiR-151 inhibited the apoptosis of endothelial cells in AS, and IL-17A was a new target for miR-151. Our findings provided a potential treatment for atherosclerosis in the treatment of AS. Graphical abstract.

Mitochondrial DNA copy number and diabetes: the Atherosclerosis Risk in Communities (ARIC) study

INTRODUCTION

Mitochondrial DNA copy number (mtDNA-CN) is a measure of mitochondrial dysfunction and is associated with diabetes in experimental models. To explore the temporality of mitochondrial dysfunction and diabetes, we estimated the prevalent and incident association of mtDNA-CN and diabetes.

RESEARCH DESIGN AND METHODS

We assessed the associations of mtDNA-CN measured from buffy coat with prevalent and incident diabetes, stratified by race, in 8954 white and 2444 black participants in the Atherosclerosis Risk in Communities (ARIC) study, an observational cohort study. Follow-up for incident analyses was complete through visit 6, 2016.

RESULTS

Mean age at mtDNA-CN measurement was 57 years and 59% were female. Prevalence of diabetes at time of mtDNA-CN measurement was higher in blacks (563/2444, 23%) than whites (855/8954, 10%). The fully adjusted odds of prevalent diabetes for the 10th vs 90th percentile of mtDNA-CN was 1.05 (95% CI 0.74 to 1.49) among black and 1.49 (95% CI 1.20 to 1.85) among white participants. Over a median follow-up time of 19 years (Q1, Q3: 11, 24 years), we observed 617 incident diabetes cases among 1744 black and 2121 cases among 7713 white participants free of diabetes at baseline. The fully adjusted hazard of incident diabetes for the 10th vs 90th percentile of mtDNA-CN was 1.07 (95% CI 0.84 to 1.38) among black and 0.97 (95% CI 0.86 to 1.10) among white participants.

CONCLUSIONS

Lower mtDNA-CN in buffy coat was associated with prevalent diabetes in white but not black ARIC participants. Lower mtDNA-CN was not associated with incident diabetes over 20 years of follow-up in whites or blacks.

Association of insulin resistance, from mid-life to late-life, with aortic stiffness in late-life: the Atherosclerosis Risk in Communities Study

Background

Insulin resistance may contribute to aortic stiffening that leads to end-organ damage. We examined the cross-sectional association and prospective association of insulin resistance and aortic stiffness in older adults without diabetes.

Methods

We analyzed 2571 men and women at Visit 5 (in 2011–2013), and 2350 men and women at repeat examinations from baseline at Visit 1 (in 1987–1989) to Visit 5 (in 2011–2013). Linear regression was used to estimate the difference in aortic stiffness per standard unit of HOMA-IR, TG/HDL-C, and TyG at Visit 5. Linear mixed effects were used to assess if high, as opposed to non-high, aortic stiffness (> 75th percentile) was preceded by a faster annual rate of change in log-HOMA-IR, log-TG/HDL-C, and log-TyG from Visit 1 to Visit 5.

Results

The mean age of participants was 75 years, 37% (n = 957) were men, and 17% (n = 433) were African American. At Visit 5, higher HOMA-IR, higher TG/HDL-C, and higher TyG were associated with higher aortic stiffness (16 cm/s per SD (95% CI 6, 27), 29 cm/s per SD (95% CI 18, 40), and 32 cm/s per SD (95% CI 22, 42), respectively). From Visit 1 to Visit 5, high aortic stiffness, compared to non-high aortic stiffness, was not preceded by a faster annual rate of change in log-HOMA-IR from baseline to 9 years (0.030 (95% CI 0.024, 0.035) vs. 0.025 (95% CI 0.021, 0.028); p = 0.15) or 9 years onward (0.011 (95% CI 0.007, 0.015) vs. 0.011 (95% CI 0.009, 0.013); p = 0.31); in log-TG/HDL-C from baseline to 9 years (0.019 (95% CI 0.015, 0.024) vs. 0.024 (95% CI 0.022, 0.026); p = 0.06) or 9 years onward (− 0.007 (95% CI − 0.010, − 0.005) vs. − 0.009 (95% CI − 0.010, − 0.007); p = 0.08); or in log-TyG from baseline to 9 years (0.002 (95% CI 0.002, 0.003) vs. 0.003 (95% CI 0.003, 0.003); p = 0.03) or 9 years onward (0 (95% CI 0, 0) vs. 0 (95% CI 0, 0); p = 0.08).

Conclusions

Among older adults without diabetes, insulin resistance was associated with aortic stiffness, but the putative role of insulin resistance in aortic stiffness over the life course requires further study.

Chronic Systemic Inflammation Is Associated With Symptoms of Late-Life Depression: The ARIC Study

OBJECTIVE

The current study examined how the pattern of systemic inflammation in the decades leading up to late-life relates to depression symptoms in older adults.

METHODS

Within the Atherosclerosis Risk in Communities Study, we measured high-sensitivity C-reactive protein (CRP), a nonspecific marker of systemic inflammation, at three visits: 21 years and 14 years before, and concurrent with the assessment of depression symptoms, defined using the 11-item Center for Epidemiologic Studies Depression (CESD) scale. We categorized participants into one of four groups based on their 21-year longitudinal pattern of elevated (≥3 mg/L) versus low (<3 mg/L) CRP (stable low; unstable low; unstable elevated; stable elevated). Analyses excluded participants with suspected depression during midlife.

RESULTS

A total of 4,614 participants were included (age at CESD assessment: 75.5 [SD: 5.1]; 59% female; follow-up time: 20.7 years [SD: 1.0]). Compared to participants who maintained low CRP levels (stable low), participants who had elevated CRP at two of three visits (unstable elevated; ß = 0.09; 95% confidence interval [CI]: 0.02, 0.17) and participants who maintained elevated CRP at all three visits (stable elevated; ß = 0.13; 95% CI: 0.05, 0.21) had greater depression symptoms as older adults, after adjusting for confounders. After excluding participants with late-life cognitive impairment, only participants with stable elevated CRP demonstrated significantly greater late-life depression symptoms. In a secondary analysis, stable elevated CRP was associated with increased risk for clinically significant late-life depression symptoms.

CONCLUSION

Chronic or repeated inflammation in the decades leading up to older adulthood is associated with late-life depression, even in the context of normal cognition.

Alcohol Consumption and Incident Kidney Disease: Results From the Atherosclerosis Risk in Communities Study

OBJECTIVE(S)

Moderate alcohol consumption has been found to be associated with lower risk of coronary heart disease and myocardial infarction, which share similar risk factors and pathophysiology with chronic kidney disease (CKD). However, there is inconsistent evidence on the association between alcohol consumption and CKD.

DESIGN AND METHODS

We conducted a prospective analysis of 12,692 participants aged 45-64 years from the Atherosclerosis Risk in Communities (ARIC) study. We categorized participants into 6 alcohol consumption categories: never drinkers, former drinkers, ≤1 drink per week, 2 to 7 drinks per week, 8 to 14 drinks per week, and ≥15 drinks per week based on food frequency questionnaire responses at visit 1 (1987-1989). Incident CKD was defined as estimated glomerular filtration rate <60 mL/minute/1.73 m2 accompanied by ≥25% estimated glomerular filtration rate decline, a kidney disease-related hospitalization or death or end-stage renal disease.

RESULTS

During a median follow-up of 24 years, there were 3,664 cases of incident CKD. Current drinkers were more likely to be men, whites, and to have a higher income level and education level. After adjusting for total energy intake, age, sex, race-center, income, education level, health insurance, smoking, and physical activity, there was no significant association between being a former drinker and risk of incident CKD. Participants who drank ≤1 drink per week, 2 to 7 drinks per week, 8 to 14 drinks per week, and ≥15 drinks per week had, respectively, a 12% (hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.79-0.97), 20% (HR: 0.80, 95% CI: 0.72-0.89), 29% (HR: 0.71, 95% CI: 0.62-0.83), and 23% (HR: 0.77, 95% CI: 0.65-0.91) lower risk of CKD compared with never drinkers.

CONCLUSION(S)

Consuming a low or moderate amount of alcohol may lower the risk of developing CKD. Therefore, moderate consumption of alcohol may not likely be harmful to the kidneys.

Midlife Systemic Inflammation Is Associated With Frailty in Later Life: The ARIC Study

BACKGROUND

Evidence suggests that systemic inflammation may have a mechanistic role in age-related frailty, yet prospective data is limited. We examined whether systemic inflammation during midlife was associated with late-life frailty within the community-based Atherosclerosis Risk in Communities Study.

METHODS

Plasma levels of four inflammatory markers (fibrinogen, von Willebrand factor, and Factor VIII, and white blood cell count) were measured during Visit 1 (1987-1989; mean age: 52 [5]), standardized into z-scores, and combined to create an inflammation composite score. High-sensitivity C-reactive protein (CRP) was measured 3 (Visit 2, 1990-1992) and 9 (Visit 4, 1996-1999) years later. Frailty was evaluated in 5,760 participants during late life (Visit 5, 2011-2013; mean age: 75 [5]). Analyses were adjusted for demographic and physiological variables, and midlife medical comorbidity using logistic regression.

RESULTS

A 1 SD increase in midlife inflammation composite score was associated with higher odds of frailty 24 years later (odds ratio [OR] = 1.39, 95% confidence interval [CI]: 1.18-1.65). Similarly, each standard deviation increase in Visit 2 CRP (OR = 1.24, 95% CI: 1.09-1.40) and Visit 4 CRP (OR = 1.35, 95% CI: 1.19-1.53) was associated with a higher odds of frailty 21 and 15 years later. Participants who maintained elevated CRP (≥3 mg/L) at Visits 2 and 4 or transitioned to a state of elevated CRP during this period were more likely to subsequently meet frailty criteria compared to those who maintained low CRP. These associations were stronger among white, compared to African American, participants (p-interactions < .038).

CONCLUSIONS

Systemic inflammation during midlife may independently promote pathophysiological changes underlying frailty in a subset of the population.

Association Between Circulating Troponin Concentrations, Left Ventricular Systolic and Diastolic Functions, and Incident Heart Failure in Older Adults

Importance

Cardiac troponin is associated with incident heart failure and greater left ventricular (LV) mass. Its association with LV systolic and diastolic functions is unclear.

Objectives

To define the association of high-sensitivity cardiac troponin T (hs-cTnT) with LV systolic and diastolic functions in the general population, and to evaluate the extent to which that association accounts for the correlation between hs-cTnT concentration and incident heart failure overall, heart failure with preserved LV ejection fraction (LVEF; HFpEF), and heart failure with LVEF less than 50%.

Design, Setting, and Participants

This analysis of the Atherosclerosis Risk in Communities (ARIC) Study, an ongoing epidemiologic cohort study in US communities, included participants without cardiovascular disease (n = 4111). Available hs-cTnT measurements for participants who attended ARIC Study visits 2 (1990 to 1992), 4 (1996 to 1998), and 5 (2011 to 2013) were assessed cross-sectionally against echocardiographic measurements taken at visit 5 and against incident health failure after visit 5. Changes in hs-cTnT concentrations from visits 2 and 4 were also examined. Data analyses were performed from August 2017 to July 2018.

Main Outcomes and Measures

Cardiac structure and function by echocardiography at visit 5, and incident heart failure during a median 4½ years follow-up after visit 5.

Results

Of the 6538 eligible participants, 4111 (62.9%) without cardiovascular disease were included. Among these participants, 2586 (62.9%) were female, and the mean (SD) age was 75 (5) years. Median (interquartile range) hs-cTnT concentration at visit 5 was 9 (7-14) ng/L and was detectable in 3946 participants (96.0%). After adjustment for demographic and clinical covariates, higher hs-cTnT levels were associated with greater LV mass index (adjusted mean [SE] for group 1: 33.8 [0.5] vs group 5: 40.1 [0.4]; P for trend < .001) and with worse diastolic function, including lower tissue Doppler imaging e' (6.00 [0.07] vs 5.54 [0.06]; P for trend < .001), higher E/e' ratio (11.4 [0.2] vs 12.9 [0.1]; P for trend < .001), and greater left atrial volume index (23.4 [0.4] vs 26.4 [0.3]; P for trend < .001), independent of LV mass index; hs-cTnT level was not associated with measures of LV systolic function. Accounting for diastolic function attenuated the association of hs-cTnT concentration with incident HFpEF by 41% and the association with combined heart failure with midrange and reduced ejection fraction combined (LVEF <50) by 17%. Elevated hs-cTnT concentration and diastolic dysfunction were additive risk factors for incident heart failure. For any value of late-life hs-cTnT levels, longer duration of detectable hs-cTnT from midlife to late life was associated with greater LV mass in late life but not with worse LV systolic or diastolic function.

Conclusions and Relevance

This study shows that higher hs-cTnT concentrations were associated with worse diastolic function, irrespective of LV mass, but not with systolic function; these findings suggest that high levels of hs-cTnT may serve as an early marker of subclinical alterations in diastolic function that may lead to a predisposition to heart failure.

Joint Associations of Obesity and NT-proBNP With the Incidence of Atrial Fibrillation in the ARIC Study

Background

Circulating NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) levels, a well‐known indicator of atrial wall stress and remodeling, inversely correlate with body mass index. Both are strongly predictive of atrial fibrillation (AF). Their potential interaction in relation to incident AF, however, has not been explored.

Methods and Results

In total, 9556 participants of the ARIC (Atherosclerosis Risk in Communities) study who had 2 measurements of NT‐proBNP and no baseline AF or heart failure were followed from 1996 to 1998 through 2016 for the occurrence of incident AF. Participants were categorized as obese (body mass index ≥30) and nonobese (body mass index <30) and by NT‐proBNP levels (using the median of 68.2 pg/mL as the cutoff). Over a median follow‐up of 18.3 years, we identified 1806 incident cases of AF. Analysis using multivariable Cox regression models showed that obese participants with high NT‐proBNP levels at visit 4 had a higher adjusted risk of incident AF (hazard ratio: 3.64; 95% CI, 3.15–4.22) compared with nonobese individuals with low NT‐proBNP levels. The association of obesity with AF risk was not modified by NT‐proBNP levels (P=0.46 for interaction). Increasing BNP among participants from 1990–1992 to 1996–1998 was associated with increased AF risk. After further adjustment for clinical risk factors and medications, results were similar.

Conclusions

Individuals who had both elevated body mass index and NT‐proBNP and were free of clinically recognized heart failure were at higher risk of AF development. Those who experienced an increase in NT‐proBNP levels between visits 2 and 4 were at higher risk of AF.

Dietary patterns and risk of incident chronic kidney disease: the Atherosclerosis Risk in Communities study

BACKGROUND

Adherence to healthy dietary patterns, measured by the Healthy Eating Index (HEI), Alternative Healthy Eating Index (AHEI), and alternate Mediterranean diet (aMed) scores, is associated with a reduced risk of cardiovascular disease. The association between these scores and chronic kidney disease (CKD) is undetermined.

OBJECTIVE

We aimed to estimate the association between the HEI, AHEI, and aMed scores and risk of incident CKD.

METHODS

We conducted a prospective analysis in 12,155 participants aged 45-64 y from the Atherosclerosis Risk in Communities (ARIC) Study. We calculated HEI-2015, AHEI-2010, and aMed scores for each participant and categorized them into quintiles of each dietary score. Incident CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2 accompanied by ≥25% decline in estimated glomerular filtration rate, a kidney disease-related hospitalization or death, or end-stage renal disease. We used cause-specific hazard models to estimate risk of CKD from the quintile of the dietary score through to 31 December 2017.

RESULTS

There were 3980 cases of incident CKD over a median follow-up of 24 y. Participants who had higher adherence to the HEI-2015, AHEI-2010, and aMed scores were more likely to be female, have higher educational attainment, higher income level, be nonsmokers, more physically active, and diabetic compared with participants who scored lower. All 3 dietary scores were associated with lower CKD risk (P-trend < 0.001). Participants who were in the highest quintile of HEI-2015 score had a 17% lower risk of CKD (HR: 0.83; 95% CI: 0.74, 0.92) compared with participants in the lowest quintile. Those in quintile 5 of AHEI-2010 and aMed scores, respectively, had a 20% and 13% lower risk of CKD compared with those in quintile 1.

CONCLUSION

Higher adherence to healthy dietary patterns during middle age was associated with lower risk of CKD.

Association Between Hypertension and Kidney Function Decline: The Atherosclerosis Risk in Communities (ARIC) Study

RATIONALE & OBJECTIVE

The relationship between hypertension, antihypertension medication use, and change in glomerular filtration rate (GFR) over time among individuals with preserved GFR requires investigation.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

14,854 participants from the Atherosclerosis Risk in Communities (ARIC) Study.

PREDICTORS

Baseline hypertension status (1987-1989) was categorized according to the 2017 American College of Cardiology/American Heart Association Clinical Practice Guideline as normal blood pressure, elevated blood pressure, stage 1 hypertension, stage 2 hypertension without medication, or stage 2 hypertension with medication.

OUTCOMES

Slope of estimated GFR (eGFR) at 5 study visits over 30 years.

ANALYTICAL APPROACH

Mixed models with random intercepts and random slopes were fit to evaluate the association between baseline hypertension status and slope of eGFR.

RESULTS

At baseline, 13.2%, 7.3%, and 19.4% of whites and 15.8%, 14.9%, and 39.9% of African Americans had stage 1 hypertension, stage 2 hypertension without medication, and stage 2 hypertension with medication. Compared with those with normal blood pressure, the annual eGFR decline was greater in people with higher blood pressure (whites: elevated blood pressure, -0.11mL/min/1.73m2; stage 1 hypertension, -0.15mL/min/1.73m2; stage 2 hypertension without medication, -0.36mL/min/1.73m2; stage 2 hypertension with medication, -0.17mL/min/1.73m2; African Americans: elevated blood pressure, -0.21mL/min/1.73m2; stage 1 hypertension, -0.16mL/min/1.73m2; stage 2 hypertension without medication, -0.50mL/min/1.73m2; stage 2 hypertension with medication, -0.16mL/min/1.73m2). The 30-year predicted probabilities of developing chronic kidney disease stage G3a+with normal blood pressure, elevated blood pressure, stage 1 hypertension, stage 2 hypertension without medication, or stage 2 hypertension with medication among whites were 54.4%, 61.6%, 64.7%, 78.1%, and 70.9%, respectively, and 55.4%, 62.8%, 60.9%, 76.1%, and 66.6% among African Americans.

LIMITATIONS

Slope estimated using a maximum of 5 eGFR assessments; differential loss to follow-up.

CONCLUSIONS

Compared to normotension, baseline hypertension status was associated with faster kidney function decline over 30-year follow-up in a general population cohort. This difference was attenuated among people using antihypertensive medications.

Serum Urate, Genetic Variation, and Prostate Cancer Risk: Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Evidence is mounting that intraprostatic inflammation influences prostate cancer development. Uric acid crystals depositing in the prostate could result in injury and inflammation, increasing prostate cancer risk.

METHODS

Included were 6,574 men ages 45-64 years who enrolled in the Atherosclerosis Risk in Communities study in 1987 to 1989. We used Cox proportional hazards regression to estimate the association of serum urate concentration alone and to improve accuracy, jointly with a genetic risk score (GRS, N = 4,983) derived from variants predictive of urate concentration, with prostate cancer (N = 813) risk.

RESULTS

Serum urate concentration or joint categories of urate concentration and GRS were not associated with prostate cancer risk (P trend for quartiles = 0.3). Results were generally similar by race and after excluding users of medications that influence uric acid.

CONCLUSIONS

Serum urate alone and with a urate-associated GRS were not associated with prostate cancer risk.

IMPACT

It is unlikely that circulating urate concentration influences prostate cancer development.

Systemic inflammation during midlife and cognitive change over 20 years: The ARIC Study

OBJECTIVE

To examine the association between systemic inflammation measured during midlife and 20-year cognitive decline.

METHODS

Within the Atherosclerosis Risk in Communities cohort study, inflammatory biomarkers were measured during middle adulthood. We created an inflammation composite score using 4 blood biomarkers measured at visit 1 (fibrinogen, white blood cell count, von Willebrand factor, and factor VIII); we measured C-reactive protein (CRP) at visit 2. Cognition was assessed over 3 visits spanning 20 years using measures of memory, executive function, and language.

RESULTS

A total of 12,336 participants (baseline age 56.8 [5.7], 21% black, 56% women) were included. After adjusting for demographic variables, vascular risk factors, and comorbidities, each standard deviation (SD) increase in midlife inflammation composite score was associated with an additional 20-year decline of -0.035 SD (95% confidence interval: -0.062 to -0.007) on the cognitive composite score. We found a similar association between each SD increase in midlife CRP level and additional 20-year cognitive decline (-0.038 SD, 95% confidence interval: -0.057 to -0.019). Participants with a midlife inflammation composite score in the top quartile had a 7.8% steeper cognitive decline, compared to participants in the lowest quartile; CRP in the top quartile was associated with an 11.6% steeper cognitive decline. In cognitive domain-specific analyses, elevated midlife inflammatory markers were most consistently associated with declines in memory. Results were similar after adjusting for attrition using inverse probability weighting.

CONCLUSIONS

Our findings highlight what may be an early pathogenic role for systemic inflammation as a driver of cognitive decline in the decades leading up to older adulthood.

Reproducibility and Variability of Protein Analytes Measured Using a Multiplexed Modified Aptamer Assay

BACKGROUND

There is growing interest in the use of multiplexed aptamer-based assays for large-scale proteomic studies. However, the analytic, short- and long-term variation of the measured proteins is largely uncharacterized.

METHODS

We quantified 4001 plasma protein analytes from 42 participants in the Atherosclerosis Risk in Communities (ARIC) Study in split samples and at multiple visits using a multiplexed modified aptamer assay. We calculated the CV, Spearman correlation, and intraclass correlation (ICC) between split samples and evaluated the short-term (4-9 weeks) and long-term (approximately 20 years) variability using paired t-tests with log-transformed protein concentrations and Bonferroni-corrected significance thresholds. We performed principal component (PC) analysis of protein analyte concentrations and evaluated their associations with age, sex, race, and estimated glomerular filtration rate (eGFR).

RESULTS

The mean baseline age was 57 years at the first visit, 43% of participants were male and 57% were white. Among 3693 protein analytes that passed quality control, half (n = 1846) had CVs < 5.0%, Spearman correlations > 0.89, and ICCs > 0.96 among the split samples. Over the short term, only 1 analyte had a statistically significant difference between the 2 time points, whereas, over approximately 20 years, 866 analytes (23.4%) had statistically significant differences (P < 1.4 × 10^-5, 681 increased, 185 decreased). PC1 had high correlations with age (-0.73) and eGFR (0.60). PC2 had moderate correlation with male sex (0.18) and white race (0.31).

CONCLUSIONS

Multiplexed modified aptamer technology can assay thousands of proteins with excellent precision. Our results support the potential for large-scale studies of the plasma proteome over the lifespan.

Longitudinal increases in blood biomarkers of inflammation or cardiovascular disease and the incidence of venous thromboembolism

Essentials Inflammatory and cardiac diseases are associated with increased venous thromboembolism (VTE) risk. Our prospective study assessed rise in inflammatory or cardiac biomarkers and VTE risk. A greater 6-year rise in N-terminal natriuretic peptide is associated with increased VTE incidence. Volume overload or impending cardiac disease may contribute to VTE occurrence.

SUMMARY

Background We previously showed that participants in the population-based Atherosclerosis Risk in Communities (ARIC) cohort with elevated levels of blood biomarkers of inflammation or cardiac disease were at increased risk of venous thromboembolism (VTE). Objective We hypothesized that ARIC participants with larger 6-year increases in the levels of three biomarkers - C-reactive protein (CRP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and troponin T - would also have an increased subsequent risk of VTE. Methods We measured changes in the levels of these biomarkers in 9844 participants from 1990-1992 to 1996-1998, and then identified VTEs through 2015. Results A greater 6-year rise in the level of NT-proBNP, but not in that of CRP or troponin T, was significantly associated with increased VTE incidence over a median of 17.6 years of follow-up. After adjustment for other VTE risk factors, those whose NT-proBNP level rose from < 100 pg mL-1 to ≥ 100 pg mL-1 had a hazard ratio for VTE of 1.44 (95% confidence interval [CI] 1.15-1.80), as compared with the reference group with an NT-proBNP level of < 100 pg mL-1 at both times. This hazard ratio was slightly higher (1.66, 95% CI 1.19-2.31) during the first 10 years of follow-up, but was attenuated (1.24, 95% CI 0.99-1.56) after adjustment for prevalent and incident coronary heart disease, heart failure, and atrial fibrillation. Conclusions The two most likely explanations for our results are that: (i) an increasing NT-proBNP level reflects increasing subclinical volume overload and potentially increased venous stasis or subclinical PE that had gone unrecognized over time; or (ii) an increasing NT-proBNP level is a risk marker for impending cardiac disease that places patients at risk of VTE.

Six-Year Change in High-Sensitivity Cardiac Troponin T and Risk of Subsequent Coronary Heart Disease, Heart Failure, and Death

IMPORTANCE

High-sensitivity cardiac troponin T (hs-cTnT) is a biomarker of cardiovascular risk and could be approved in the United States for clinical use soon. However, data linking long-term temporal change in hs-cTnT to outcomes are limited, particularly in primary prevention settings.

OBJECTIVE

To examine the association of 6-year change in hs-cTnT with incident coronary heart disease (CHD), heart failure (HF), and all-cause mortality.

DESIGN, SETTING, AND PARTICIPANTS

This prospective observational cohort study, performed from January 1, 1990, to December 31, 2011, included 8838 participants with biracial representation from the Atherosclerosis Risk in Communities Study who were initially free of CHD and HF and who had hs-cTnT measured twice, 6 years apart. Data analysis was performed from October 28, 2014, to March 9, 2016.

MAIN OUTCOME AND MEASURES

Risk factor and temporal hs-cTnT data were collected. Using Cox proportional hazards regression, we examined the association of hs-cTnT change with subsequent CHD, HF, and death during a maximum of 16 years. Improvement in discrimination was determined by the Harrell C statistic.

RESULTS

Of the 8838 participants (mean age, 56 years; 5215 female [59.0%]; 1891 black [21.4%]) there were 1157 CHD events, 965 HF events, and 1813 deaths overall. Incident detectable hs-cTnT (baseline, <0.005 ng/mL; follow-up, ≥0.005 ng/mL) was independently associated with subsequent CHD (hazard ratio [HR], 1.4; 95% CI, 1.2-1.6), HF (HR, 2.0; 95% CI, 1.6-2.4), and death (HR, 1.5; 95% CI, 1.3-1.7), relative to an hs-cTnT level less than 0.005 ng/mL at both visits. In addition, HRs as high as 4 for CHD and death and 8 for HF were recorded among individuals with the most marked hs-cTnT increases (eg, baseline, < 0.005 ng/mL; follow-up, ≥0.014 ng/mL). Risk for subsequent outcomes was lower among those with relative hs-cTnT reductions greater than 50% from baseline. Furthermore, information on hs-cTnT change improved discrimination for HF and death when added to a model that included traditional risk factors, N-terminal pro-brain natriuretic peptide, and baseline hs-cTnT level. Among individuals with adjudicated HF hospitalizations, hs-cTnT change appeared to be similarly associated with HF with reduced and preserved ejection fraction.

CONCLUSIONS AND RELEVANCE

Temporal increases in hs-cTnT, suggestive of progressive myocardial damage, are independently associated with incident CHD, death, and, above all, HF. Serial determination of hs-cTnT trajectory adds clinically relevant information to baseline testing and may be useful in prognostic assessments and the targeting of prevention strategies to high-risk individuals, especially among persons with stage A or B HF.

Association of N-terminal pro B-type natriuretic peptide (NT-proBNP) change with the risk of atrial fibrillation in the ARIC cohort

BACKGROUND

Circulating N-terminal pro B-type natriuretic peptide (NT-proBNP) predicts incidence of atrial fibrillation (AF), but the association of longitudinal changes in NT-proBNP concentrations with incident AF has not been explored.

METHODS

We studied 9705 individuals without prevalent AF in 1996-1998 and with available NT-proBNP measurements obtained in samples collected during two visits in 1990-1992 (visit 2) and 1996-1998 (visit 4) in the Atherosclerosis Risk in Communities (ARIC) Study. Participants were followed through the end of 2013. AF was ascertained from electrocardiograms, hospital discharge codes, and death certificates. Multivariable Cox regression was used to evaluate the association of absolute change in log-transformed NT-proBNP [ln(NT-proBNP)] with incident AF. We also assessed the impact of adding ln(NT-proBNP) change as a predictor of AF by difference in the C-statistic and net reclassification improvement (NRI).

RESULTS

Over a median follow up of 16 years, there were 1503 incident cases of AF. The means (SD) ln(NT-proBNP) at visit 2 and visit 4 were 3.83 (1.01) and 4.35 (0.94), respectively. There was a 0.52 (0.79) increase in ln(NT-proBNP) over the 6-year period. Greater increases in ln(NT-proBNP) were associated with higher risk of AF [hazard ratio, 2.82 (95% confidence interval 2.34, 3.39), comparing top to bottom quintiles, and 1.74 (1.61, 1.87) per 1-unit increase in ln(NT-proBNP)]. Adding ln(NT-proBNP) change to a model with multiple predictors including baseline NT-proBNP had relatively limited impact in the C-statistic (increase from 0.748, 95%CI 0.736-0.761, to 0.762, 95%CI 0.750, 0.774). Adding ln(NT-proBNP) change to initial predictive models resulted in a categorical NRI of 0.062 (95% CI 0.033, 0.092) and a continuous NRI of 0.092 (95%CI, 0.017, 0.182).

CONCLUSION

Positive NT-proBNP change is associated with an increased incidence rate of AF. Adding NT-proBNP change into the prediction model modestly improved incident AF prediction. Future studies should assess the value of monitoring NT-proBNP concentration among individuals at high risk of developing AF.

Diabetes and Trajectories of Estimated Glomerular Filtration Rate: A Prospective Cohort Analysis of the Atherosclerosis Risk in Communities Study

OBJECTIVE

To characterize long-term kidney disease trajectories in persons with and without diabetes in a general population.

RESEARCH DESIGN AND METHODS

We classified 15,517 participants in the community-based Atherosclerosis Risk in Communities (ARIC) study by diabetes status at baseline (1987-1989; no diabetes, undiagnosed diabetes, and diagnosed diabetes). We used linear mixed models with random intercepts and slopes to quantify estimated glomerular filtration rate (eGFR) trajectories at four visits over 26 years.

RESULTS

Adjusted mean eGFR decline over the full study period among participants without diabetes was -1.4 mL/min/1.73 m2/year (95% CI -1.5 to -1.4), with undiagnosed diabetes was -1.8 mL/min/1.73 m2/year (95% CI -2.0 to -1.7) (difference vs. no diabetes, P < 0.001), and with diagnosed diabetes was -2.5 mL/min/1.73 m2/year (95% CI -2.6 to -2.4) (difference vs. no diabetes, P < 0.001). Among participants with diagnosed diabetes, risk factors for steeper eGFR decline included African American race, APOL1 high-risk genotype, systolic blood pressure ≥140 mmHg, insulin use, and higher HbA1c.

CONCLUSIONS

Diabetes is an important risk factor for kidney function decline. Those with diagnosed diabetes declined almost twice as rapidly as those without diabetes. Among people with diagnosed diabetes, steeper declines were seen in those with modifiable risk factors, including hypertension and glycemic control, suggesting areas for continued targeting in kidney disease prevention.

Predictive metabolomic signatures of end-stage renal disease: A multivariate analysis of population-based data

The variability of molecular signatures and predictive low molecular weight markers of chronic kidney disease (CKD) in different populations are poorly understood. Thus, in a large sample with 4763 people we compare the molecular signatures and metabolites with diagnostic relevance in plasma and urine of CKD patients of different geographical origins. From an integrated model based on dynamic networks and multivariate statistics, metabolites with predictive value obtained from targeted and untargeted molecular analysis, interactions between metabolic pathways affected by CKD, and the methodological quality of metabolomic studies were analyzed. The metabolites 3-methylhistidine, citrulline, kynurenine, p-cresol sulfate, urea, and citrate presented consistent expression in all population groups. Only increased kynurenine and p-cresol sulfate in plasma samples obtained acceptable scores as CKD biomarkers, independent of geographic origin. Metabolites such as leucine, alanine, isoleucine, serine, histidine, and citrate were nodal points, indicating that protein metabolism pathways are similarly impaired in Asian, European and North American patients. Based on our integrated model, we show that the metabolome of CKD patients exhibits a strong geographic influence, leading to unique metabolic signatures. Contrary to the likelihood of molecular similarities between geographically distinct populations, metabolic convergences in protein metabolism pathways and the molecules kynurenine and p-cresol sulfate were relevant as general predictors of CKD. In general, the quality assessment indicated that the current evidence is based on research models with variable methodological quality, whose limitations described in this study should be considered in the refinement of molecular approaches.

Socioeconomic status and risk of kidney dysfunction: the Atherosclerosis Risk in Communities study

Background

There is strong evidence of an association between socioeconomic status (SES) and end-stage renal disease (ESRD). However, the association of SES with the risk of chronic kidney disease (CKD) and the rate of change in kidney function is unclear.

Methods

A cohort of 14 086 participants with an estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 at baseline in the Atherosclerosis Risk in Communities study (1987–89) were studied. The association of annual household income, educational attainment and neighborhood deprivation with incident ESRD, incident CKD and change in eGFR using four measurements over ∼23 years was assessed.

Results

A total of 432 participants developed ESRD and 3510 developed CKD over a median follow-up time of ∼23 years. After adjustment for demographics and baseline eGFR, the hazard ratio (HR) for incident ESRD compared with the high-income group was 1.56 [95% confidence interval (CI) 1.22–1.99 in the medium-income group and 2.30 (95% CI 1.75–3.02) in the low-income group (P-trend < 0.001), and for CKD was 1.10 (95% CI 1.01–1.20) in the medium-income group and 1.30 (95% CI 1.17–1.44) in the low-income group (P-trend < 0.001). After full adjustments, the HR for ESRD was 1.33 (95% CI 1.03–1.70) in the medium-income group and 1.50 (95% CI 1.14–1.98) in the low-income group (P-trend = 0.003) and for CKD was 1.01 (95% CI 0.92–1.10) in the medium-income group and 1.04 (95% CI 0.93–1.16) in the low-income group (P-trend = 0.50). The eGFR decline was 5% and 15% steeper in the medium- and low-income groups, respectively, after full adjustment (P-trend < 0.001). Results were similar, with lower educational attainment and higher neighborhood deprivation being associated with adverse outcomes.

Conclusions

SES (annual household income, educational attainment or neighborhood deprivation) was associated not only with ESRD risk but also with eGFR decline, although the association with CKD appeared weaker.

The association of mid-to late-life systemic inflammation with white matter structure in older adults: The Atherosclerosis Risk in Communities Study

We examined whether the pattern of middle- to late-life systemic inflammation was associated with white matter (WM) structural abnormalities in older adults. A total of 1532 participants (age = 76.5; standard deviations = 5.4) underwent 3T brain magnetic resonance imaging to quantify white matter hyperintensity volume and whole-brain WM microstructural integrity (fractional anisotropy, mean diffusivity). High-sensitivity C-reactive protein (CRP), a marker of systemic inflammation, was measured at 3 visits (21 and 14 years before, and concurrent with, neuroimaging). Participants were categorized into 1 of 6 groups based on their 21-year pattern of low (<3 mg/L) versus elevated (≥3 mg/L) CRP. Compared to the group with low CRP at all 3 visits, the group that transitioned from low to elevated CRP during midlife demonstrated greatest white matter hyperintensity volume and poorest WM microstructural integrity, after adjusting for demographic variables and cardiovascular risk factors. Participants with high CRP at all visits also demonstrated greater WM structural abnormalities, but only after accounting for differential attrition. These results suggest that increasing and persistent inflammation in the decades spanning middle-to late-life may promote WM disease in older adults.

Coffee Consumption and Incident Kidney Disease: Results From the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Moderate coffee consumption has been suggested to be associated with lower risk for chronic conditions such as diabetes, a major precursor to chronic kidney disease (CKD). However, the association between coffee and CKD has not been fully established. STUDY DESIGN: Prospective cohort study.

SETTING & PARTICIPANTS

14,209 participants aged 45 to 64 years from the Atherosclerosis Risk in Communities (ARIC) Study.

PREDICTORS

Coffee consumption (cups per day) was assessed at visits 1 (1987-1989) and 3 (1993-1995) using food frequency questionnaires.

OUTCOMES

Incident CKD defined as estimated glomerular filtration rate < 60mL/min/1.73m² accompanied by ≥25% estimated glomerular filtration rate decline, CKD-related hospitalization or death, or end-stage renal disease.

RESULTS

There were 3,845 cases of incident CKD over a median of 24 years of follow-up. Men, whites, current smokers, and participants without comorbid conditions were more likely to consume higher amounts of coffee per day. After adjustment for demographic, clinical, and dietary factors, higher categories of coffee consumption were associated with lower risk for incident CKD compared with those who never consumed coffee (HR for <1 cup per day, 0.90 [95% CI, 0.82-0.99]; 1-<2 cups per day, 0.90 [95% CI, 0.82-0.99]; 2-<3 cups per day, 0.87 [95% CI, 0.77-0.97]; and ≥3 cups per day, 0.84 [95% CI, 0.75-0.94]). In continuous analysis, for each additional cup of coffee consumed per day, risk for incident CKD was lower by 3% (HR, 0.97; 95% CI, 0.95-0.99; P<0.001).

LIMITATIONS

Self-reported coffee consumption and observational design.

CONCLUSIONS

Participants who drank higher amounts of coffee had lower risk for incident CKD after adjusting for covariates. Coffee consumers may not be at adverse risk for kidney disease.

Relation of Lifestyle Factors and Life's Simple 7 Score to Temporal Reduction in Troponin Levels Measured by a High-Sensitivity Assay (from the Atherosclerosis Risk in Communities Study)

The impact of lifestyle-related factors on temporal decreases in high-sensitivity cardiac troponin T (hs-cTnT), possibly reflecting reversal of subclinical myocardial damage, has not been evaluated in a community-based setting. We measured hs-cTnT twice, 6 years apart, in 9,256 participants from the Atherosclerosis Risk in Communities (ARIC) Study who were free from baseline cardiovascular disease. We used Poisson and multinomial regression to evaluate the associations of cigarette smoking, alcohol consumption, body mass index, healthy diet score, physical activity, and Life's Simple 7 (LS7) score (a composite measure of lifestyle-related health factors) with 6-year decreases in hs-cTnT. Of the 3,017 patients with detectable baseline hs-cTnT (≥5 ng/L), 2,418 (80%) remained detectable, whereas 599 (20%) had undetectable levels (<5 ng/L) at the 6-year follow-up visit. Patients with a body mass index of <30 kg/m2, adherence to American Heart Association's physical activity guidelines, and average or optimal LS7 scores were more likely to improve from a detectable to an undetectable hs-cTnT level during follow-up. There was a robust association between optimal LS7 score and temporal hs-cTnT reduction (relative risk 1.64, 95% confidence interval 1.11 to 2.42, for baseline ≥5 ng/L and for follow-up <5 ng/L). A greater duration of exposure to average or optimal LS7 score was also associated with increased likelihood of temporal hs-cTnT reduction (p-trend <0.001). In conclusion, we found that lifestyle factors and the LS7 score were associated with reversal of subclinical myocardial damage. In conclusion, our results support the growing evidence that hs-cTnT levels change in response to lifestyle modifications and hs-cTnT may serve as a useful dynamic surrogate for monitoring cardiovascular risk.

The Association of Mid- and Late-Life Systemic Inflammation with Brain Amyloid Deposition: The ARIC-PET Study

BACKGROUND

Although inflammation has been implicated in the pathogenesis of Alzheimer's disease, the effects of systemic inflammation on brain amyloid deposition remain unclear.

OBJECTIVE

We examined the association of midlife and late-life systemic inflammation with late-life brain amyloid levels in a community sample of non-demented older adults from the Atherosclerosis Risk in Communities (ARIC) - PET Study.

METHODS

339 non-demented participants (age: 75 [SD 5]) were recruited from the ARIC Study to undergo florbetapir PET (amyloid) imaging. Blood levels of high sensitivity C-reactive protein (CRP), a marker of systemic inflammation, were measured 22 years (Visit 2), 16 years (Visit 4), and up to 2 years before PET imaging (Visit 5). Elevated brain amyloid deposition (standardized uptake value ratio >1.2) was the primary outcome.

RESULTS

Our primary analyses found no association of midlife and late-life CRP with late-life brain amyloid levels. However, in secondary stratified analyses, we found that higher midlife (Visit 2) CRP was associated with elevated amyloid among males (OR 1.65, 95% CI: 1.13-2.42), and among white (OR 1.33, 95% CI: 1.02-1.75), but not African American, participants (p-interactions<0.05). Among male participants, those who maintained high CRP levels (≥3 mg/L) throughout mid- and late-life were most likely to have elevated brain amyloid (OR, 8.81; 95% CI: 1.23, 62.91).

CONCLUSIONS

Although our primary analysis does not support an association between systemic inflammation and brain amyloid deposition, we found evidence for sex- and race-dependent associations. However, findings from subgroup analyses should be interpreted with caution.

Prediction of Type 2 Diabetes by Hemoglobin A1c in Two Community-Based Cohorts

OBJECTIVE

Hemoglobin A_1c (HbA_1c) can be used to assess type 2 diabetes (T2D) risk. We asked whether HbA_1c was associated with T2D risk in four scenarios of clinical information availability: 1) HbA_1c alone, 2) fasting laboratory tests, 3) clinic data, and 4) fasting laboratory tests and clinic data.

RESEARCH DESIGN AND METHODS

We studied a prospective cohort of white (N = 11,244) and black (N = 2,294) middle-aged participants without diabetes in the Framingham Heart Study and Atherosclerosis Risk in Communities study. Association of HbA_1c with incident T2D (defined by medication use or fasting glucose [FG] ≥126 mg/dL) was evaluated in regression models adjusted for 1) age and sex (demographics); 2) demographics, FG, HDL, and triglycerides; 3) demographics, BMI, blood pressure, and T2D family history; or 4) all preceding covariates. We combined results from cohort and race analyses by random-effects meta-analyses. Subsidiary analyses tested the association of HbA_1c with developing T2D within 8 years or only after 8 years.

RESULTS

Over 20 years, 3,315 individuals developed T2D. With adjustment for demographics, the odds of T2D increased fourfold for each percentage-unit increase in HbA_1c. The odds ratio (OR) was 4.00 (95% CI 3.14, 5.10) for blacks and 4.73 (3.10, 7.21) for whites, resulting in a combined OR of 4.50 (3.35, 6.03). After adjustment for fasting laboratory tests and clinic data, the combined OR was 2.68 (2.15, 3.34) over 20 years, 5.79 (2.51, 13.36) within 8 years, and 2.23 (1.94, 2.57) after 8 years.

CONCLUSIONS

HbA_1c predicts T2D in different common scenarios and is useful for identifying individuals with elevated T2D risk in both the short- and long-term.