Identification of Protein Biomarkers of the Dietary Approaches to Stop Hypertension Diet in Randomized Feeding Studies and Validation in an Observational Study

Abstract

Background The Dietary Approaches to Stop Hypertension (DASH) diet is recommended for cardiovascular disease prevention. We aimed to identify protein biomarkers of the DASH diet using data from 2 randomized feeding studies and validate them in an observational study, the ARIC (Atherosclerosis Risk in Communities) study. Methods and Results Large-scale proteomic profiling was conducted in serum specimens (SomaLogic) collected at the end of 8-week and 4-week DASH diet interventions in multicenter, randomized controlled feeding studies of the DASH trial (N=215) and the DASH-Sodium trial (N=396), respectively. Multivariable linear regression models were used to compare the relative abundance of 7241 proteins between the DASH and control diet interventions. Estimates from the 2 trials were meta-analyzed using fixed-effects models. We validated significant proteins in the ARIC study (N=10 490) using the DASH diet score. At a false discovery rate <0.05, there were 71 proteins that were different between the DASH diet and control diet in the DASH and DASH-Sodium trials. Nineteen proteins were validated in the ARIC study. The 19 proteins collectively improved the prediction of the DASH diet intervention in the feeding studies (range of difference in C statistics, 0.267-0.313; P<0.001 for both tests) and the DASH diet score in the ARIC study (difference in C statistics, 0.017; P<0.001) beyond participant characteristics. Conclusions We identified 19 proteins robustly associated with the DASH diet in 3 studies, which may serve as biomarkers of the DASH diet. These results suggest potential pathways that are impacted by consumption of the DASH diet. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT03403166, NCT00000608.

Keywords: DASH diet; biomarkers; feeding studies; observational study; protein.

Figure 1. Volcano plots of β coefficients and false discovery rate (FDR)–adjusted P values for proteins differing significantly between the Dietary Approaches to Stop Hypertension (DASH) diet compared with the control diet in the DASH and DASH‐Sodium trials.

The dashed horizontal line represents FDR <0.05, and the vertical dashed line is set at the $\mathrm{\beta }$ coefficient of 0. Proteins located to the right of the vertical line indicate that the abundance of proteins was higher in participants consuming the DASH compared with the control diet, and proteins located to the left of the vertical line indicate that the abundance of proteins was lower in participants consuming the DASH compared with the control diet. $\mathrm{\beta }$ and P values were calculated using multivariable linear regression models that were adjusted for age, sex, race and ethnicity, and body mass index in each study. Estimates were meta‐analyzed across the DASH and DASH‐Sodium trials using fixed‐effects models. Study‐specific $\mathrm{\beta }$ coefficients, P values, and the full name of all of these proteins are presented in Table 2.

Figures 2. β coefficients and 95% CIs of 19 proteins that were significantly different between the Dietary Approaches to Stop Hypertension (DASH) diet and the control diet in the trials (DASH trial [N=215] and DASH‐Sodium trial [N=396]) (left panel) and were validated using the DASH diet score in the ARIC (Atherosclerosis Risk in Communities) study (N=10 490) (right panel).

In the DASH and DASH‐Sodium trials, $\mathrm{\beta }$ coefficients and 95% CIs were calculated using multivariable linear regression models, adjusting for age, sex, race and ethnicity, and body mass index. Estimates were meta‐analyzed across the 2 trials using fixed‐effects models. In the ARIC study, $\mathrm{\beta }$ coefficients and 95% CIs were calculated using multivariable linear regression models that were adjusted for age, sex, race, study center, education level, alcohol drinking status, cigarette smoking status, physical activity score, body mass index, diabetes status, and estimated glomerular filtration rate. AFM indicates afamin; ASAH2, neutral ceramidase; CCL25, C‐C motif chemokine 25; CD163, scavenger receptor cysteine‐rich type 1 protein M130; CTHRC1, collagen triple helix repeat‐containing protein 1; EGFR, epidermal growth factor receptor; FOLR2, folate receptor β; GGH, γ‐glutamyl hydrolase; INHBA, inhibin β A chain; INHBC, inhibin β C chain; KREMEN1, kremen protein 1; LYVE1, lymphatic vessel endothelial hyaluronic acid receptor 1; MET, hepatocyte growth factor receptor; PCOLCE, procollagen C‐endopeptidase enhancer 1; PDRG1, p53 and DNA damage‐regulated protein 1; PGLYRP2, N‐acetylmuramoyl‐L‐alanine amidase; RBP4, retinol‐binding protein 4; S100A14, protein S100‐A14; and VAT1, synaptic vesicle membrane protein VAT‐1 homolog.