RESUMEN
BACKGROUND: There have been mixed results reported internationally when associating vegetarian dietary patterns with all-cause and cause-specific mortalities. OBJECTIVE: To extend our previous results by evaluating, with a larger number of deaths (N=12515), cause-specific mortalities comparing different vegetarian types to non-vegetarians. METHODS: This prospective study used data from the Adventist Health Study-2 cohort. Mortality was ascertained between study baseline, 2002-2007 and follow-up through 2015. Dietary data were collected at baseline using a validated quantitative food frequency questionnaire and then categorized into five dietary patterns: non-vegetarian, semi-vegetarian, pesco-vegetarian, lacto-ovo-vegetarian, and vegan. Main outcomes and measures include all-cause and cause-specific mortalities using Cox proportional hazards regression models and competing risk methods. RESULTS: The analytic sample included 88400 participants who provided 971424 person-years of follow-up. We report results as estimated at ages 65 and 85 years due to age-dependence of many hazard ratios (HR's). Compared to non-vegetarians, vegetarians had lower risks of mortality (HR's and 95% confidence interval - 95% CI at age 65; followed by same at age 85 years in parentheses), overall (0.89[0.83,0.95];0.98[0.91,1.04]), from renal failure (0.52[0.38,0.70]; 0.65[0.55,0.76]), infectious disease (0.57[0.40,0.82];0.90[0.70,1.17]), diabetes (0.51[0.33,0.78]; 0.69[0.53,0.88]), select cardiac (0.75[0.65,0.87]; 0.89[0.83,0.95]), and ischemic heart disease causes (0.730.59,0.90]; 0.84[0.75,0.94]). Vegans, lacto-ovo-vegetarians and pesco-vegetarians were also observed to have lower risks of total mortality and several similar cause-specific mortalities. However, higher cause-specified neurological mortalities were observed among older vegetarians (estimated at age 85 years), specifically stroke (HR=1.17[1.02,1.33]), dementia (HR=1.13[1.00,1.27]), and Parkinson's Disease (HR=1.37[0.98,1.91]). Results in Black subjects for vegetarian/nonvegetarian comparisons largely followed the same trends, but HR's were less precise due to smaller numbers. CONCLUSIONS: Vegetarian diets are associated with lower risk for all-cause and many cause-specific mortalities, especially among males and in younger subjects. However, higher risks were observed among older vegetarians for stroke and dementia. These results need further support and investigation.
RESUMEN
BACKGROUND: Black Americans suffer disparities in risk for cardiometabolic and other chronic diseases. Findings from the Adventist Health Study-2 (AHS-2) cohort have shown associations of plant-based dietary patterns and healthy lifestyle factors with prevention of such diseases. Hence, it is likely that racial differences in metabolic profiles correlating with disparities in chronic diseases are explained largely by diet and lifestyle, besides social determinants of health. METHODS: Untargeted plasma metabolomics screening was performed on plasma samples from 350 participants of the AHS-2, including 171 Black and 179 White participants, using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and a global platform of 892 metabolites. Differences in metabolites or biochemical subclasses by race were analyzed using linear regression, considering various models adjusted for known confounders, dietary and/or other lifestyle behaviors, social vulnerability, and psychosocial stress. The Storey permutation approach was used to adjust for false discovery at FDR < 0.05. RESULTS: Linear regression revealed differential abundance of over 40% of individual metabolites or biochemical subclasses when comparing Black with White participants after adjustment for false discovery (FDR < 0.05), with the vast majority showing lower abundance in Blacks. Associations were not appreciably altered with adjustment for dietary patterns and socioeconomic or psychosocial stress. Metabolite subclasses showing consistently lower abundance in Black participants included various lipids, such as lysophospholipids, phosphatidylethanolamines, monoacylglycerols, diacylglycerols, and long-chain monounsaturated fatty acids, among other subclasses or lipid categories. Among all biochemical subclasses, creatine metabolism exclusively showed higher abundance in Black participants, although among metabolites within this subclass, only creatine showed differential abundance after adjustment for glomerular filtration rate. Notable metabolites in higher abundance in Black participants included methyl and propyl paraben sulfates, piperine metabolites, and a considerable proportion of acetylated amino acids, including many previously found associated with glomerular filtration rate. CONCLUSIONS: Differences in metabolic profiles were evident when comparing Black and White participants of the AHS-2 cohort. These differences are likely attributed in part to dietary behaviors not adequately explained by dietary pattern covariates, besides other environmental or genetic factors. Alterations in these metabolites and associated subclasses may have implications for the prevention of chronic diseases in Black Americans.