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Dysregulation of the immune system and dietary patterns that increase inflammation can increase the risk for cognitive decline, but the mechanisms by which inflammatory nutritional habits may affect the development of cognitive impairment in aging are not well understood. To determine whether plasma proteins linked to inflammatory diet predict future cognitive impairment, we applied high-throughput proteomic assays to plasma samples from a subset (n = 1528) of Women’s Health Initiative Memory Study (WHIMS) participants (mean [SD] baseline age, 71.3 [SD 3.8] years). Results provide insights into how inflammatory nutritional patterns are associated with an immune-related proteome and identify a group of proteins (CXCL10, CCL3, HGF, OPG, CDCP1, NFATC3, ITGA11) related to future cognitive impairment over a 14-year follow-up period. Several of these inflammatory diet proteins were also associated with dementia risk across two external cohorts (ARIC, ESTHER), correlated with plasma biomarkers of Alzheimer’s disease (AD) pathology (Aβ42/40) and/or neurodegeneration (NfL), and related to an MRI-defined index of neurodegenerative brain atrophy in a separate cohort (BLSA). In addition to evaluating their biological relevance, assessing their potential role in AD, and characterizing their immune-tissue/cell-specific expression, we leveraged published RNA-seq results to examine how the in vitro regulation of genes encoding these candidate proteins might be altered in response to an immune challenge. Our findings indicate how dietary patterns with higher inflammatory potential relate to plasma levels of immunologically relevant proteins and highlight the molecular mediators which predict subsequent risk for age-related cognitive impairment.

We studied the replication and generalization of previously identified metabolites potentially associated with global cognitive function in multiple race/ethnicities and assessed the contribution of diet to these associations.We tested metabolite-cognitive function associations in U.S.A. Hispanic/Latino adults (n = 2222) from the Community Health Study/ Study of Latinos (HCHS/SOL) and in European (n = 1365) and African (n = 478) Americans from the Atherosclerosis Risk In Communities (ARIC) Study. We applied Mendelian Randomization (MR) analyses to assess causal associations between the metabolites and cognitive function and between Mediterranean diet and cognitive function.Six metabolites were consistently associated with lower global cognitive function across all studies. Of these, four were sugar-related (e.g., ribitol). MR analyses provided weak evidence for a potential causal effect of ribitol on cognitive function and bi-directional effects of cognitive performance on diet.Several diet-related metabolites were associated with global cognitive function across studies with different race/ethnicities.Metabolites associated with cognitive function in Puerto Rican adults were recently identified. We demonstrate the generalizability of these associations across diverse race/ethnicities. Most identified metabolites are related to sugars. Mendelian Randomization (MR) provides weak evidence for a causal effect of ribitol on cognitive function. Beta-cryptoxanthin and other metabolites highlight the importance of a healthy diet.

Greater adherence to plant-based diets is associated with a lower risk of incident chronic kidney disease (CKD). Metabolomics can help identify blood biomarkers of plant-based diets and enhance understanding of underlying mechanisms.Using untargeted metabolomics, we aimed to identify metabolites associated with 4 plant-based diet indices (PDIs) (overall PDI, provegetarian diet, healthful PDI, and unhealthful PDI) and incident CKD in 2 subgroups within the Atherosclerosis Risk in Communities study.We calculated 4 PDIs based on participants' responses on an FFQ. We used multivariable linear regression to examine the association between 4 PDIs and 374 individual metabolites, adjusting for confounders. We used Cox proportional hazards regression to evaluate associations between PDI-related metabolites and incident CKD. Estimates were meta-analyzed across 2 subgroups (n1 = 1762; n2 = 1960). We calculated C-statistics to assess whether metabolites improved the prediction of those in the highest quintile compared to the lower 4 quintiles of PDIs, and whether PDI- and CKD-related metabolites predicted incident CKD beyond the CKD prediction model.We identified 82 significant PDI-metabolite associations (overall PDI = 27; provegetarian = 17; healthful PDI = 20; unhealthful PDI = 18); 11 metabolites overlapped across the overall PDI, provegetarian diet, and healthful PDI. The addition of metabolites improved prediction of those in the highest quintile as opposed to the lower 4 quintiles of PDIs compared with participant characteristics alone (range of differences in C-statistics = 0.026-0.104; P value ≤ 0.001 for all tests). Six PDI-related metabolites (glycerate, 1,5-anhydroglucitol, γ-glutamylalanine, γ-glutamylglutamate, γ-glutamylleucine, γ-glutamylvaline), involved in glycolysis, gluconeogenesis, pyruvate metabolism, and γ-glutamyl peptide metabolism, were significantly associated with incident CKD and improved prediction of incident CKD beyond the CKD prediction model (difference in C-statistics for 6 metabolites = 0.005; P value = 0.006).In a community-based study of US adults, we identified metabolites that were related to plant-based diets and predicted incident CKD. These metabolites highlight pathways through which plant-based diets are associated with incident CKD.

BACKGROUND: The DASH (Dietary Approaches to Stop Hypertension) diets reduced blood pressure (BP) in the DASH and DASH-Sodium trials, but the underlying mechanisms are unclear. We identified metabolites associated with systolic BP or diastolic BP (DBP) changes induced by dietary interventions (DASH versus control arms) in 2 randomized controlled feeding studies—the DASH and DASH-Sodium trials. METHODS: Metabolomic profiling was conducted in serum and urine samples collected at the end of diet interventions: DASH (n=219) and DASH-Sodium (n=395). Using multivariable linear regression models, associations were examined between metabolites and change in systolic BP and DBP. Tested for interactions between diet interventions and metabolites were the following comparisons: (1) DASH versus control diets in the DASH trial (serum), (2) DASH high-sodium versus control high-sodium diets in the DASH-Sodium trial (urine), and (3) DASH low-sodium versus control high-sodium diets in the DASH-Sodium trial (urine). RESULTS: Sixty-five significant interactions were identified (DASH trial [serum], 12; DASH high sodium [urine], 35; DASH low sodium [urine], 18) between metabolites and systolic BP or DBP. In the DASH trial, serum tryptophan betaine was associated with reductions in DBP in participants consuming the DASH diets but not control diets ( P interaction, 0.023). In the DASH-Sodium trial, urine levels of N-methylglutamate and proline derivatives (eg, stachydrine, 3-hydroxystachydrine, N-methylproline, and N-methylhydroxyproline) were associated with reductions in systolic BP or DBP in participants consuming the DASH diets but not control diets ( P interaction, CONCLUSIONS: We identified metabolites that were associated with BP lowering in response to dietary interventions. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03403166 (DASH trial). URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00000608 (DASH-Sodium trial).

Metabolomic signatures of incident diabetes remain largely unclear for the U.S. Hispanic/Latino population, a group with high diabetes burden. We evaluated the associations of 624 known serum metabolites (measured by a global, untargeted approach) with incident diabetes in a subsample (n = 2,010) of the Hispanic Community Health Study/Study of Latinos without diabetes and cardiovascular disease at baseline (2008–2011). Based on the significant metabolites associated with incident diabetes, metabolite modules were detected using topological network analysis, and their associations with incident diabetes and longitudinal changes in cardiometabolic traits were further examined. There were 224 incident cases of diabetes after an average 6 years of follow-up. After adjustment for sociodemographic, behavioral, and clinical factors, 134 metabolites were associated with incident diabetes (false discovery rate–adjusted P < 0.05). We identified 10 metabolite modules, including modules comprising previously reported diabetes-related metabolites (e.g., sphingolipids, phospholipids, branched-chain and aromatic amino acids, glycine), and 2 reflecting potentially novel metabolite groups (e.g., threonate, N-methylproline, oxalate, and tartarate in a plant food metabolite module and androstenediol sulfates in an androgenic steroid metabolite module). The plant food metabolite module and its components were associated with higher diet quality (especially higher intakes of healthy plant-based foods), lower risk of diabetes, and favorable longitudinal changes in HOMA for insulin resistance. The androgenic steroid module and its component metabolites decreased with increasing age and were associated with a higher risk of diabetes and greater increases in 2-h glucose over time. We replicated the associations of both modules with incident diabetes in a U.S. cohort of non-Hispanic Black and White adults (n = 1,754). Among U.S. Hispanic/Latino adults, we identified metabolites across various biological pathways, including those reflecting androgenic steroids and plant-derived foods, associated with incident diabetes and changes in glycemic traits, highlighting the importance of hormones and dietary intake in the pathogenesis of diabetes.

Background Glycated albumin may provide complementary information to hemoglobin A1c (HbA1c). We compared cross-sectional associations of HbA1c and glycated albumin with chronic kidney disease (CKD) in US adults. Methods We included 10 923 adults (9955 without diagnosed diabetes, 968 with a diabetes diagnosis) from the National Health and Nutrition Examination Survey 1999–2004. We examined continuous associations and clinical cut points for HbA1c among those without diabetes ( Results There were J-shaped associations for both glycated albumin and HbA1c with CKD. Persons without a history of diabetes and very low glycated albumin or HbA1c were more likely to have CKD compared to those without diabetes and normoglycemia. The odds ratios (ORs) for CKD were 1.32 (95% CI, 1.12–1.55) for HbA1c 5.7% to 6.4% and 2.04 (95% CI, 1.28–3.25) for HbA1c ≥6.5%. The ORs for glycated albumin were 1.27 (95% CI, 1.06–1.51) and 2.48 (95% CI, 1.50–4.08) for glycated albumin 14.4% to 17.8% and ≥17.9%, respectively. The inclusion of glycated albumin in the model with HbA1c and traditional risk factors modestly but significantly improved the model fit (P value = 0.006). Conclusions Glycated albumin and HbA1c were similarly associated with prevalent CKD. Glycated albumin provides complementary information to HbA1c for prevalent CKD.

Introduction: Older populations have been growing dramatically worldwide. Aging may lead to changes in diet quality. There is a need to better understand dietary intake during late-life and the impact on health outcomes. Hypothesis: We hypothesized that adherence to healthy dietary patterns, i.e., the Dietary Approaches to Stop Hypertension (DASH) and the alternate Mediterranean (aMED) diets, would be associated with lower risk of all-cause mortality. Methods: Atherosclerosis Risk in Communities (ARIC) study participants aged 60-83 years who attended a study visit in 2005-2006 were included (n=1,069). Dietary intake was assessed with a 131-item Willett food frequency questionnaire. Adherence to healthy dietary patterns was assessed using a priori scores for DASH and aMED. We used Cox proportional hazards models to study the association between tertiles of healthy dietary patterns and all-cause mortality through December 31, 2019. Results: There were 452 deaths observed over a median follow-up of 13 years (12,564.3 person-years). Incidence rates were lower in the third tertile, indicating high adherence to healthy dietary patterns (DASH: 32.9 per 1,000 person-years; aMED: 28.5 per 1,000 person-years), compared to the first tertile (DASH: 39.6 per 1,000 person-years; aMED: 40.0 per 1,000 person-years). Participants in the third vs. first tertile for adherence to the DASH and aMED diets had a 22% and 37% lower risk of all-cause mortality, respectively [hazard ratio for DASH: 0.78 (95% CI, 0.62 - 0.98); aMED: 0.63 (95% CI, 0.49 - 0.83)] after adjusting for age, sex, race, study centers and total energy intake. An approximately linear, inverse relationship was observed between healthy dietary patterns and risk of all-cause mortality for both DASH and aMED ( Figure ). Conclusion: Higher adherence to healthy dietary patterns, specifically the DASH and aMED diets, is associated with lower risk of mortality among older adults. Following a healthy diet may improve survival in the aging population.

Introduction: There is a lack of objective biomarkers of dietary intake. Untargeted studies can unbiasedly identify dairy biomarkers and inform the creation of robust dietary assessment tools that integrate questionnaire and biospecimen data. Methods: Dairy products from interviewer-administered questionnaires were categorized as either low-fat or high-fat dairy. Total dairy was a composite of low-fat and high-fat dairy items. Linear regression models were used to assess associations between dairy intake and 360 serum metabolites in the Atherosclerosis Risk in Communities (ARIC) Study (n=3907). Significant associations were then tested for replication in the Bogalusa Heart Study (BHS) (n=819). Results: In the ARIC study, 34 dairy-metabolite associations were identified (total dairy, n = 16; low-fat dairy, n = 10; high-fat dairy, n = 8). Total dairy shared 7 metabolic associations each with low-fat dairy and high-fat dairy. Low-fat dairy was associated with pantothenate, vitamin B5, and the catabolic product of vitamin B6, pyridoxate. High-fat dairy was associated with one amino acid, 3-hydroxy-2-ethylpropionate, and eight lipid metabolites, including myristate (14:0), 10-nonadecenoate (19:1n9), and myristoleate (14:1n5). Of the metabolites available for replication in BHS (total dairy, n = 15; low-fat dairy, n = 9; high-fat dairy, n = 8), 2 total dairy metabolites were replicated and 2 low-fat dairy metabolites were replicated ( Table ). Conclusions: We identified metabolomic markers of total, low-fat, and high-fat dairy. Pantothenate, myristate (14:0), and tiglyl carnitine replicated across two large, diverse study populations, suggesting that they are markers of dairy consumption.

Introduction: The Dietary Approaches to Stop Hypertension (DASH) diet significantly reduced blood pressure (BP) in the DASH and DASH-Sodium trials, but the underlying mechanisms are unclear. Hypothesis: We hypothesized that certain metabolites will be associated with BP reductions. Methods: Metabolomic profiling was conducted at the end of the diet interventions for participants randomly assigned to the DASH or control diet in multicenter, controlled feeding studies: DASH (N=219) and DASH-Sodium trials (N=395). Using multivariable linear regression models to examine the association between metabolites and BP change, we tested for interactions between diet and metabolites for the following comparisons: 1) DASH vs. control diets in the DASH trial, 2) DASH-high sodium vs. control-high sodium diets in the DASH-Sodium trial, and 3) DASH-low sodium vs. control-high sodium diets in the DASH-Sodium trial. Pathway overrepresentation analysis was constructed for significant metabolites. Results: Identified were 65 significant interactions [DASH=12; DASH-high sodium=35; DASH-low sodium=18]. Most amino acids (16/19), cofactors and vitamins (15/15), xenobiotics (9/13), peptides (4/5), and a nucleotide (1/1) were higher in participants consuming the DASH diets vs. the control diets. These metabolites were associated with BP reductions in participants consuming the DASH diets, but not control diets ( Figure ). Many lipid metabolites (10/12) were lower in participants consuming the DASH vs. the control diets. Lipid concentrations were associated with BP elevations in participants consuming the DASH diets and with BP reductions in participants consuming the control diets. Metabolites associated with tocopherol metabolism, ceramides, and pantothenate and CoA metabolism were overrepresented. Conclusions: Using data from randomized feeding studies, we identified metabolites that were associated with BP lowering. These metabolites highlight the pathways through which DASH diet reduced BP.

Introduction: Ultra-processed food (UPF) consumption has an adverse impact on cardiovascular health. Current research is primarily based on non-US study populations. The purpose of our study was to estimate the association between UPF consumption and risk of incident hypertension in a population of middle-aged black and white men and women. Methods: Atherosclerosis Risk in Communities (ARIC) study participants who were hypertension free at baseline and had complete dietary, covariate, and hypertension data from visit 1 (1987 - 1989) were included (n = 8,866). Participants were followed through November 30, 2019 for the development of hypertension defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or recent patient-reported use of blood pressure lowering medication. Processing level was determined using the NOVA classification system. Data were analyzed using three progressively adjusted Cox proportional hazards regression models. Results: 6,960 participants developed hypertension during a median follow-up of 13 years. Participants in the highest quartile of UPF consumption were 9% more likely to develop incident hypertension than those in the lowest quartile (model 2 HR: 1.09; CI: 1.02-1.16; P for trend = 0.01) ( Table ). Participants who were in the highest quartile of sugar-sweetened beverages and red and processed meat consumption had a 20% higher risk of hypertension (model 2 HR, 1.20; CI, 1.12 - 1.28; P for trend Conclusions: High UPF consumption, specifically sugar-sweetened beverages and red and processed meat, was associated with higher risk of hypertension, whereas minimally or unprocessed food consumption was associated with lower hypertension risk.

Background: High dietary calcium and phosphorus intakes may accelerate vascular calcification. A few studies have explored the association of dietary calcium and phosphorus intakes with vascular calcification but reported inconsistent results. Most studies relied on dietary assessment at one time point and evaluated only coronary artery calcification. Aim: To assess the associations of dietary calcium and phosphorus intakes over two time points during middle age with coronary artery and extra-coronary calcification at older age. Methods: We studied 1,940 ARIC participants who underwent chest CT scans at ≥75 years of age in 2018-19 and completed a 66-item food frequency questionnaire at two earlier visits (1987-89 and 1993-95). We calculated the average of dietary calcium and phosphorus intakes across these two visits. Calcification was quantified as Agatston score in coronary arteries, ascending aorta, descending aorta, aortic valve ring, aortic valve, and mitral valve. We ran multivariable linear (for continuous Agatston score) and logistic regression models (for Agatston score >75 th percentile). Results: The mean dietary calcium and phosphorus intake was 659 mg/day and 1,074 mg/day, respectively. Overall, we did not observe any positive associations of dietary calcium intake with vascular/valvular calcification. Rather, we saw its inverse association with ascending aorta calcification (Figure). In contrast, dietary phosphorus was not associated with the calcification of any vascular beds. The results were largely similar in linear regression models and after excluding 332 participants (17%) taking calcium supplements. Conclusion: Dietary calcium intake at middle age was largely neutral in its association with vascular calcification while showing a mild inverse association with ascending aorta calcification at older age. No evident associations were seen for dietary phosphorus. Our findings do not support a concern that a calcium or phosphorus-rich diet may accelerate vascular calcification.

Background: Numerous studies have shown inverse associations between serum magnesium (Mg) levels and risk of cardiovascular disease (CVD), but studies of dietary Mg have not been consistent. Aim: The association of a Mg-rich diet score with risks of incident CVD, coronary heart disease (CHD), and ischemic stroke in the Atherosclerosis Risk in Communities (ARIC) study was examined. Methods: There were 15,022 Black and White adults without prevalent CVD included in this analysis. Diet was assessed at two visits using an interviewer-administered 66-item food frequency questionnaire. A Mg-rich diet score was created including whole grain products, nuts, fruits, vegetables, legumes, coffee, and tea. Cox proportional hazard regression evaluated the associations of incident CVD, CHD and stroke through 2019 across quintiles of Mg-rich diet score adjusted for demographic characteristics, lifestyle factors, and clinical characteristics. Results: Participants in the highest quintile of Mg-rich diet score compared to the lowest quintile consumed more servings of Mg-rich foods and fiber and less refined grains, red and processed meat, total fat and saturated fat. Over 30 years of follow up, a Mg-rich diet score was inversely associated with incident CVD (HR Q5 vs Q1 =0.88, 95% CI 0.78-0.99, p trend =0.03) and CHD (HR=0.83, 95% CI 0.72-0.96, p trend =0.01); however the diet-stroke association was null (HR=1.08, 95% CI 1.07-1.09, p trend =0.93) (Table). Conclusions: Consuming a diet rich in whole grains, nuts, fruits and vegetables, legumes, coffee and tea is consistent with a lower long-term risk of CVD and CHD.

Introduction: There is inconsistent evidence on the efficacy of a low-protein diet for patients with chronic kidney disease (CKD) and there is a lack of objective biomarkers of dietary intake. The purpose of this study was to identify plasma metabolites associated with dietary intake of protein among children with CKD and to assess whether protein-related metabolites are associated with CKD progression. Methods: We conducted non-targeted metabolomics using plasma samples from 484 Chronic Kidney Disease in Children (CKiD) participants. Multivariable linear regression estimated the cross-sectional association between 949 known, non-drug metabolites and dietary intake of dairy, nuts and beans, red and processed meat, fish, chicken, and eggs, adjusting for demographic, clinical, and dietary covariates. Cox proportional hazards regression models assessed the prospective association between protein-related metabolites and CKD progression defined as kidney replacement therapy or 50% eGFR reduction, adjusting for demographic and clinical covariates. We used a false discovery rate Results: Fifty-seven unique metabolites were significantly associated with dietary protein intake (dairy: n=21; nuts and beans: n=13; red and processed meat: n=20; fish: n=2; chicken: n=3; eggs: n=0). Among them, ten metabolites were significantly associated with CKD progression (TABLE) , including one amino acid, one cofactor and vitamin, four lipids, two nucleotides, one peptide, and one xenobiotic. 1-(1-enyl-palmitoyl)-2-oleoyl-GPE (P-16:0/18:1) was positively associated with dietary intake of red and processed meat and CKD progression, and 3-ureidopropionate was inversely associated with dietary intake of red and processed meat and CKD progression. Conclusion: Untargeted plasma metabolomic profiling revealed metabolites associated with dietary intake of protein and CKD progression in a pediatric population.

Introduction: N-terminal pro-brain-type natriuretic peptide (NT-proBNP) is widely used as a diagnostic biomarker for heart failure. Higher diet quality is associated with lower risk of cardiovascular disease. However, the association between diet and subclinical cardiovascular disease, as assessed by biomarker concentrations, is less well-studied. Hypothesis: We hypothesized that higher diet quality, assessed by the Healthy Eating Index-2015 (HEI-2015), would be associated with lower serum levels of NT-proBNP. Methods: We included 9,782 adults from the National Health and Nutrition Examination Survey (NHANES), 1999-2004. The HEI-2015 ranges from 0 to 100, with higher scores indicating better diet quality, and was categorized into sex-specific quintiles. Weighted multivariable linear regression models were used to estimate associations between the overall HEI-2015 score as well as its 13 components and log-transformed NT-proBNP. Results: Among 9,782 participants, mean age was 45 years, 48% were men, and 72% were non-Hispanic White adults. After adjusting for sociodemographic characteristics, lifestyle factors, and medical history, persons in the highest HEI-2015 quintile had a 10.0% lower NT-proBNP level compared to those in the lowest HEI-2015 quintile (95% CI: -17.7% to -2.6%). There was a dose-response relationship between HEI-2015 and NT-proBNP ( Figure ). For each 1-unit higher sodium and added sugars score, NT-proBNP was lower by 7.7% and 6.8% respectively (95% CI: -13.8 % to -2.2%, and 95% CI: -13.1% to -0.9% respectively). Conclusion: Higher diet quality, especially lower intakes of sodium and added sugars, was associated with lower serum levels of NT-proBNP.

Peer reviewed: True, Funder: University of New South Wales; FundRef: http://dx.doi.org/10.13039/501100001773, OBJECTIVE: To assess the prospective associations of circulating levels of omega 3 polyunsaturated fatty acid (n-3 PUFA) biomarkers (including plant derived α linolenic acid and seafood derived eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) with incident chronic kidney disease (CKD). DESIGN: Pooled analysis. DATA SOURCES: A consortium of 19 studies from 12 countries identified up to May 2020. STUDY SELECTION: Prospective studies with measured n-3 PUFA biomarker data and incident CKD based on estimated glomerular filtration rate. DATA EXTRACTION AND SYNTHESIS: Each participating cohort conducted de novo analysis with prespecified and consistent exposures, outcomes, covariates, and models. The results were pooled across cohorts using inverse variance weighted meta-analysis. MAIN OUTCOME MEASURES: Primary outcome of incident CKD was defined as new onset estimated glomerular filtration rate

BACKGROUND AND AIMS: Various food groups have been associated with measures of left ventricular geometry and function. Whether the Dietary Approaches to Stop Hypertension (DASH) dietary pattern in mid-life is associated with a favorable cardiac structure and function later in life is unknown. METHODS AND RESULTS: The study population consisted of the Atherosclerosis Risk in Communities study participants free of cardiovascular disease at study visit 3 in 1993 to 1995. Dietary intake was assessed by food frequency questionnaire at study visits 1 (1987–1989) and 3 (1993–1995). Participants who underwent transthoracic echocardiograms at the Jackson field center at visit 3 (n=1,974) and at all field centers at study visit 5 (2011–2013; n=4,651) were included in this study. General linear regression was used to evaluate associations between dietary intake and markers of cardiac structure and function adjusting for potential confounders. Higher DASH score was associated with lower left ventricle mean wall thickness and higher absolute value of longitudinal strain at visit 5 (p(trend)=0.004 and

BACKGROUND: The blood pressure–lowering effects of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern and reduced sodium intake are well established. The effects on other biomarkers related to vascular health are of interest and might assist in explaining the effects of the DASH diet and sodium reduction. OBJECTIVES: We hypothesized that a low-sodium DASH diet improves (lowers) biomarkers of inflammation [C-reactive protein (CRP) and soluble urokinase plasminogen activator receptor (suPAR)] and mineral metabolism [phosphorus and fibroblast growth factor-23 (FGF23)]. METHODS: We conducted a secondary analysis of the DASH-Sodium trial using frozen serum samples. This controlled feeding study randomly assigned 412 adults (≥22 y) with elevated blood pressure (120–159/80–95 mmHg) to consume either a DASH diet or control diet. Within each arm, participants received 3 sodium levels [low (1150 mg), intermediate (2300 mg), high (3450 mg)] in random sequence, each for 30 d. To maximize contrast, samples collected at the end of the low-sodium DASH (n = 198) and high-sodium control (n = 194) diets were compared. Between-diet differences in serum CRP, suPAR, phosphorus, and FGF23 concentrations were assessed using linear regression adjusted for age, sex, race, income, education, smoking status, and BMI. RESULTS: CRP concentrations did not differ between groups (P = 0.83), but suPAR was higher after the low-sodium DASH diet than the high-sodium control [geometric mean 2470 pg/mL (95% CI: 2380, 2560 pg/mL), compared with 2290 pg/mL (95% CI: 2210, 2380 pg/mL); P = 0.006]. Phosphorus was higher after the low-sodium DASH diet [geometric mean 3.50 mg/dL (95% CI: 3.43, 3.57 mg/dL)] compared with the high-sodium control diet [geometric mean 3.39 mg/dL (95% CI: 3.33, 3.46 mg/dL); P = 0.04]. FGF23 was also higher after the low-sodium DASH diet [geometric mean 35.3 pg/mL (95% CI: 33.3, 37.3 pg/mL) compared with 28.2 pg/mL (95% CI: 26.6, 29.8 pg/mL); P

Background In individuals with chronic kidney disease (CKD), healthy dietary patterns are inversely associated with CKD progression. Metabolomics, an approach that measures many small molecules in biofluids, can identify biomarkers of healthy dietary patterns. Objectives We aimed to identify known metabolites associated with greater adherence to 4 healthy dietary patterns in CKD patients. Methods We examined associations between 486 known plasma metabolites and Healthy Eating Index (HEI)-2015, Alternative Healthy Eating Index (AHEI)-2010, the Dietary Approaches to Stop Hypertension (DASH) diet, and alternate Mediterranean diet (aMED) in 1056 participants (aged 21-74 y at baseline) in the Chronic Renal Insufficiency Cohort (CRIC) Study. Usual dietary intake was assessed using a semiquantitative FFQ. We conducted multivariable linear regression models to study associations between healthy dietary patterns and individual plasma metabolites, adjusting for sociodemographic characteristics, health behaviors, and clinical factors. We used principal component analysis to identify groups of metabolites associated with individual food components within healthy dietary patterns. Results After Bonferroni correction, we identified 266 statistically significant diet-metabolite associations (HEI: n = 60; AHEI: n = 78; DASH: n = 77; aMED: n = 51); 78 metabolites were associated with >1 dietary pattern. Lipids with a longer acyl chain length and double bonds (unsaturated) were positively associated with all 4 dietary patterns. A metabolite pattern low in saturated diacylglycerols and triacylglycerols, and a pattern high in unsaturated triacylglycerols was positively associated with intake of healthy food components. Plasmalogens were negatively associated with the consumption of nuts and legumes and healthy fat, and positively associated with the intake of red and processed meat. Conclusions We identified many metabolites associated with healthy dietary patterns, indicative of food consumption. If replicated, these metabolites may be considered biomarkers of healthy dietary patterns in patients with CKD.

Nutritional epidemiology seeks to understand nutritional determinants of disease in human populations using experimental and observational study designs. Though randomized controlled trials provide the strongest evidence of causality, the expense and difficulty of sustaining adherence to dietary interventions are substantial barriers to investigating dietary determinants of kidney disease. Therefore, nutritional epidemiology commonly employs observational study designs, particularly prospective cohort studies, to investigate long-term associations between dietary exposures and kidney disease. Due to the covarying nature and synergistic effects of dietary components, holistic characterizations of dietary exposures that simultaneously consider patterns of foods and nutrients regularly consumed are generally more relevant to disease etiology than single nutrients or foods. Dietary intakes have traditionally been self-reported and are subject to bias. Statistical methods including energy adjustment and regression calibration can reduce random and systematic measurement errors associated with self-reported diet. Novel approaches that assess diet more objectively are gaining popularity but have not yet fully replaced self-report and require refinement and validation in populations with chronic kidney disease. More accurate and frequent diet assessment in existing and future studies will yield evidence to better personalize dietary recommendations for the prevention and treatment of kidney disease.

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 103 mL/min/1.73 m2, and median BMI was 27 kg/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/1.73 m2 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/1.73 m2 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/1.73 m2 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/1.73 m2 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.

RATIONALE & OBJECTIVE: Current dietary guidelines recommend that chronic kidney disease (CKD) patients restrict individual nutrients, such as sodium, potassium, phosphorus and protein. This approach can be difficult for patients to implement and ignores important nutrient interactions. Dietary patterns are an alternative method to intervene on diet. Our objective was to define the associations of four healthy dietary patterns with risk of CKD progression and all-cause mortality among people with CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,403 participants aged 21–74 years with an estimated glomerular filtration rate (eGFR) of 20–70 mL/min/1.73 m(2) and dietary data in the Chronic Renal Insufficiency Cohort (CRIC) study. EXPOSURES: Healthy Eating Index-2015 (HEI-2015), Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean diet (aMed), and Dietary Approaches to Stop Hypertension (DASH) diet scores were calculated from food frequency questionnaires. OUTCOMES: 1) CKD progression defined as ≥50% eGFR decline, kidney transplantation, or dialysis and 2) all-cause mortality. ANALYTICAL APPROACH: Cox proportional hazards regression models adjusted for demographic, lifestyle, and clinical covariates to estimate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: There were 855 cases of CKD progression and 773 deaths over a maximum of 14 years. Compared with participants with the lowest adherence, the most highly adherent tertile of AHEI-2010, aMed, and DASH had lower adjusted risk of CKD progression with the strongest results for aMed (HR: 0.75, 95% CI: 0.62–0.90). Compared with participants with the lowest adherence, the highest adherence tertiles for all scores had lower adjusted risk of all-cause mortality for each index (24–31% lower risk). LIMITATIONS: Self-reported dietary intake. CONCLUSIONS: Greater adherence to several healthy dietary patterns is associated with a lower risk of CKD progression and all-cause mortality among people with CKD. Guidance to adopt healthy dietary patterns can be considered as a strategy for managing CKD. INDEX WORDS: dietary patterns, nutrition, kidney disease, renal, mortality

BACKGROUND: High diet quality is associated with a lower risk of chronic diseases. Metabolomics can be used to identify objective biomarkers of diet quality. OBJECTIVES: We used metabolomics to identify serum metabolites associated with 4 diet indices and the components within these indices in 2 samples from African Americans and European Americans. METHODS: We studied cross-sectional associations between known metabolites and Healthy Eating Index (HEI)-2015, Alternative Healthy Eating Index (AHEI)-2010, the Dietary Approaches to Stop Hypertension Trial (DASH) diet, alternate Mediterranean diet (aMED), and their components using untargeted metabolomics in 2 samples (n(1) = 1,806, n(2) = 2,056) of the Atherosclerosis Risk in Communities study (aged 45–64 y at baseline). Dietary intakes were assessed using an FFQ. We used multivariable linear regression models to examine associations between diet indices and serum metabolites in each sample, adjusting for participant characteristics. Metabolites significantly associated with diet indices were meta-analyzed across 2 samples. C-statistics were calculated to examine if these candidate biomarkers improved prediction of individuals in the highest compared with lowest quintile of diet scores beyond participant characteristics. RESULTS: Seventeen unique metabolites (HEI: n = 6; AHEI: n = 5; DASH: n = 14; aMED: n = 2) were significantly associated with higher diet scores after Bonferroni correction in sample 1 and sample 2. Six of 17 significant metabolites [glycerate, N-methylproline, stachydrine, threonate, pyridoxate, 3-(4-hydroxyphenyl)lactate)] were associated with ≥1 dietary pattern. Candidate biomarkers of HEI, AHEI, and DASH distinguished individuals with highest compared with lowest quintile of diet scores beyond participant characteristics in samples 1 and 2 (P value for difference in C-statistics