Serum Metabolite 1-Methylhistidine, a Marker of Red Meat and Poultry Consumption, Independently Associates With Increases in Systolic and Diastolic Blood Pressure in Middle-Aged Adults

Introduction: Red meat consumption associates with heightened cardiometabolic risk. Urinary metabolite 1-methylhistidine (1-MTH) has been shown to correlate with red meat, poultry, and to a lesser extent fish consumption, serving as a quantitative biological marker of intake. We aimed to confirm this relationship and assess the novel role of serum 1-MTH in blood pressure (BP) among a biracial (African American-White) community-based cohort of middle-aged adults. Methods: This study consisted of 655 participants of the Bogalusa Heart Study (25.0% African-American, 60.8% female, aged 33.6-58.1 years) not taking antihypertensive medication. From 2013-2018, systolic and diastolic BP were recorded using an oscillometric method. Fasting serum 1-MTH was quantified using liquid chromatography-tandem mass spectroscopy using a median standardized scale. Red meat, poultry, and fish intake were quantified by food-frequency questionnaires. Analyses of animal food consumption with 1-MTH were performed using bivariate linear regression. Multivariable linear regression assessed the independent association of 1-MTH with systolic and diastolic BP in combined and race-stratified analyses, adjusting for a wide variety of traditional demographic, dietary and cardiometabolic risk factors. Results: Red meat (B=0.004; p=0.001) and poultry (B=0.005; p=0.05), but not fish intake, were significantly associated with serum 1-MTH. Serum 1-MTH had a significant positive association with both systolic (B=10.45, p=0.04) and diastolic BP (B=6.44, p=0.04) consistently in African-Americans, but not Whites. Among a subgroup of 86 individuals who were normotensive at baseline with repeat outcome measures (median follow-up time=2.98 years), we observed a 5.30 and 5.13 mmHg per-year increase in systolic (p=0.03) and diastolic BP (p=0.002), respectively, for every one unit increase in serum 1-MTH. Conclusion: Red meat and poultry intake correlate with serum 1-MTH. Notably, serum 1-MTH independently associates with considerable increases in systolic and diastolic BP, more consistently in African-Americans compared to Whites. These findings may aid in strengthening cardiometabolic prevention efforts via dietary recommendations, in a race-specific fashion.