Dietary vitamin E intake and new-onset hypertension

Nutrition and Hypertension Researches in 2023: focus on salt intake and blood pressure

Hypertension is a major global health issue that contributes significantly to cardiovascular morbidity and mortality. The management and prevention of hypertension often involve nutritional and dietary modifications, which are considered effective non-pharmacological strategies. In 2023, the Hypertension Research published several papers highlighting nutrition and hypertension. In addition, multiple studies published in leading journals explored the relationship between salt intake and blood pressure (BP) in 2023. In this mini-review, we summarize the key findings of nutritional studies published in the Hypertension Research in 2023. This mini-review also highlights significant findings from the latest research on salt intake and its impact on BP. The new findings from nutritional studies will provide deeper insights on planning dietary strategies for the management of hypertension.

Associations of composite dietary antioxidant index with premature death and all-cause mortality: a cohort study

Although previous evidence indicates that the composite dietary antioxidant index (CDAI) is negatively associated with health outcomes, no studies have explored the association between CDAI and premature death. This research utilized a cohort study design with 37,301 participants from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2018. Cox proportional hazard regression was employed to analyze the association between CDAI and premature death and all-cause mortality. Restricted cubic spline (RCS) analysis was performed to examine the nonlinear relationship between variables, and Kaplan-Meier analysis was used to evaluate survival outcomes over time. Sensitivity and subgroup analyses were conducted to assess the reliability of the findings. During a median follow-up period of 8.25 years, 4487 deaths were recorded, with 1671 classified as premature. The study revealed a negative correlation between CDAI and premature death (Per-SD hazard ratio [HR] 0.91, 95% CI 0.85-0.97; quartiles [Q4:Q1] HR 0.83, 95% CI: 0.70, 0.98) as well as all-cause mortality (Per-SD HR 0.96, 95% CI 0.92-1.00; quartiles [Q4:Q1] HR 0.91, 95%CI: 0.82, 1.01). The RCS analyses indicated a 'U' shaped relationship between CDAI and premature death and all-cause mortality. The threshold effect analysis pinpointed the inflection points for CDAI relative to premature death and all-cause mortality at 1.42 and 1.48, respectively. Kaplan-Meier curves illustrated that the likelihood of individual survival increases with higher CDAI quartiles. The results highlight the significance of dietary antioxidant intake in enhancing extending lifespan. Further research is needed to investigate the underlying mechanisms and determine optimal intake levels for improving health outcomes.

Negative Association between Vitamin E Intake and Remnant Cholesterol: The National Health and Nutrition Examination Survey 2007-2020

BACKGROUND

Remnant cholesterol (RC) is a risk factor for the development of atherosclerosis. Vitamin E has antioxidant properties, making it a potentially effective management tool for preventing cardiovascular disease (CVD). However, the relationship between vitamin E intake and RC remains unclear.

METHODS

We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) Survey 2007-2020. 11,585 participants (aged ≥20, 48% male) were included. Information on vitamin E intake (dietary vitamin E intake and total vitamin E intake) was collected. RC was defined as serum total cholesterol minus high-density lipoprotein and low-density lipoprotein cholesterol. Survey-weighted linear regression models and a restricted cubic spline (RCS) were used to test the relationship between vitamin E intake and RC. Subgroup analyses and interaction tests were also performed to verify the robustness of the results.

RESULTS

After adjusting for all potential confounders (demographics, socioeconomic status, lifestyle, diet, and comorbidities), dietary vitamin E intake was negatively associated with RC (β = -0.21, 95% CI: (-0.29, -0.12), p < 0.0001), and this negative association was also present between total vitamin E intake and RC (β = -0.12, 95% CI: (-0.18, -0.06), p < 0.0001). The RCS analysis revealed a nonlinear negative association between vitamin E intake and RC. The negative correlation existed in different subgroups, with no interaction except for the "use of vitamin E supplements" subgroup.

CONCLUSION

Vitamin E intake showed a protective association with RC. The results suggest that increasing dietary vitamin E intake may help reduce RC levels and CVD risk.

Joint and independent associations of dietary antioxidant intakes with all-cause and cardiovascular mortality among patients with hypertension: a population-based cohort study

BACKGROUND

The evidence regarding dietary antioxidant intake and all-cause and cardiovascular disease (CVD) mortality among patients with hypertension is scarce.

METHODS AND RESULTS

This study included 16,190 adults with hypertension from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Death outcomes were ascertained by linkage to National Death Index records through December 31, 2019. Overall dietary intake was estimated with composite dietary antioxidant index (CDAI). Cox proportional hazards models were used to estimate the risk for all-cause and CVD mortality. Kaplan-Meier curve was used to illustrate the survival probabilities among CDAI quartiles. Weighted quantile sum (WQS) regression was conducted to evaluate the joint and independent associations of antioxidants with all-cause and CVD mortality. The median (interquartile range) age of participants was 59.00 (47.00, 69.00) years. During a median of 94 months of follow-up, 3,858 deaths were documented. Compared to participants with the lowest quartile of CDAI, the multivariable adjusted HR and 95% CI for participants with the highest quartile was 0.76 (0.64, 0.91) for all-cause mortality. The highest quartile (Q4) of vitamin E (HR = 0.69; 95% CI, 0.59-0.80), selenium (HR = 0.84; 95% CI, 0.70-1.00) and total carotenoids (HR = 0.86; 95% CI, 0.75-0.98) intakes were negatively associated with all-cause mortality. Vitamin E and selenium intakes might be the major contributors to this negative relationship. The highest quartile (Q4) of vitamin E (HR = 0.72; 95% CI, 0.56-0.93) intake was negatively associated with CVD mortality.

CONCLUSION

Higher overall dietary antioxidant intake was significantly associated with decreased all-cause and CVD mortality among patients with hypertension. Further randomized controlled trials are required to confirm our findings.

Association between dietary antioxidant indices and hypertension among Chinese adults

The effect of dietary antioxidants on blood pressure (BP) regulation and hypertension risk remains largely unknown. This study aimed to comprehensively assess the impacts of dietary antioxidants on systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), and hypertension risk among Chinese adults. The cross-sectional study assessed data from 12,046 Chinese adults, evaluating dietary antioxidant quality scores (DAQS) and total antioxidant capacity (DTAC) via a validated food frequency questionnaire. MAP was derived using the formula DBP + (0.412 ×PP), with PP calculated as SBP - DBP. The relationship between DAQS, DTAC, and hypertension prevalence was analyzed using multivariable logistic regression. Among participants not taking antihypertensive medications, those in the highest groups of DTAC and DAQS had significantly lower SBP, DBP, MAP, and PP compared to those in the lowest groups (all p-trends <0.001). Relative to the lowest quintile (Q1) of DTAC (adjusted odds ratios (OR) for hypertension decreased in Q2 (OR 0.90, 95%CI 0.79-1.03), Q3 (OR 0.65, 95% CI 0.56-0.76), Q4 (OR 0.51, 95% CI 0.43-0.60), and Q5 (OR 0.38, 95% CI 0.31-0.46) (p trend <0.001). For DQAS, hypertension OR of category 5 was 0.38 (95% CI 0.32-0.46) compared to that of category 1. Increased vitamin A, Zinc, and selenium intake correlated with reduced hypertension risk. A significant non-linear DTAC and linear DAQS relationships were observed and hypertension risk. Antioxidant-rich diets markedly lowered SBP, DBP, MAP, PP, and hypertension risk.

Dietary antioxidant index and hypertension in the Iranian population: a nested case-control study within the Fasa adults cohort study

Introduction

Hypertension (HTN) is a prevalent condition associated with numerous cardiovascular and non-cardiac complications. Lifestyle interventions, including dietary adjustments, offer promising avenues for hypertension management. However, the precise relationship between dietary antioxidants and hypertension risk necessitates further investigation. This study aimed to elucidate the association between the Dietary Antioxidant Index (DAI) and hypertension risk using a nested case-control design.

Method

A matched nested case-control study was conducted within the Fasa Adult Cohort Study (FACS), comprising 975 participants aged 35-70 years. Cases (n = 325) were hypertensive patients, while controls (n = 650) were individuals without hypertension, matched for sex and age. Dietary intake was assessed using a validated food frequency questionnaire, and DAI was computed based on standardized intake of antioxidants. Conditional logistic regression models were employed to evaluate the association between DAI and hypertension risk, adjusting for confounding variables.

Results

A significant inverse correlation was observed between DAI and hypertension risk across all models (OR = 0.89; 95% CI = 0.86-0.93, p < 0.001). This association remained robust after adjusting for potential confounders, including BMI, smoking, lipid profile, blood glucose levels, and educational status. In conclusion, higher DAI values were associated with a reduced risk of hypertension, highlighting the potential benefits of antioxidant-rich diets in hypertension prevention.

Conclusion

These findings underscore the importance of dietary interventions as a complementary approach to hypertension management.

Association of dietary and circulating antioxidant vitamins with metabolic syndrome: an observational and Mendelian randomization study

Aims

The objective of this study was to investigate the associations of dietary and circulating antioxidant vitamins with metabolic syndrome (MetS), and to assess causality using Mendelian randomization (MR).

Methods

This study included 10,308 participants from the National Health and Nutrition Examination Survey. The associations of vitamins A, C, E and carotenoids with MetS were assessed using multivariable weighted logistic regression analysis. Subsequently, the MR approach was employed to test the causal associations, with inverse variance weighted (IVW) serving as the primary analysis.

Results

Observationally, dietary vitamin A (OR=0.852, 95%CI: 0.727-0.999), C (OR=0.802, 95%CI: 0.675-0.952), carotene (OR=0.832, 95%CI: 0.706-0.982), and β-carotene (OR=0.838, 95%CI: 0.706-0.995) in quartile 4 had lower incidents of MetS, when compared to quartile 1. Circulating vitamin C and carotene were also present inversely associated with MetS, while the vitamin A and E both increased this risk. IVW-MR confirmed the associations of dietary vitamin A (OR=0.920, 95%CI: 0.861-0.984), vitamin C (OR=0.905, 95%CI: 0.836-0.979) and carotene (OR=0.918, 95%CI: 0.865-0.974) with MetS. However, there was only circulating β-carotene (OR=0.909, 95%CI: 0.857-0.965) was found to be causally associated with MetS.

Conclusions

Observational and MR studies have shown that adequate dietary intake of vitamin A, C and carotenoids may help to reduce the risk of MetS.

Individual and interaction effects of monounsaturated fatty acids on their associations with hypertension in Chinese residents

Currently, associations between dietary intakes of individual monounsaturated fatty acids (MUFAs) and hypertension were not well disclosed, and the interaction effects of MUFAs on their associations with hypertension were unknown. Obesity was correlated with both MUFAs and hypertension, while if anthropometric obesity indices performed mediating roles in associations between MUFAs and hypertension remained underdetermined. In our study, 8509 Chinese adults investigated from 2004 to 2011 were included. Dietary information collection and physical examinations were performed at baseline and each timepoint of follow-up. As we found, inverse associations of MUFA17, MUFA18 and MUFA20 with hypertension were statistically significant after adjustments, hazard ratios (HRs) were 0.87, 0.90 and 0.91, respectively. MUFA15 was positively associated with hypertension, with an HR of 1.07 (95% confidence interval: 1.01, 1.12). By performing principal component analysis (PCA) to estimate the joint effects of MUFAs on hypertension, the PCA score of MUFAs was only inversely associated with blood pressure. No joint effect was observed in g-computation analyses. Both linear and nonlinear interactions of MUFAs on their associations with hypertension were estimated using restricted cubic spline analysis. The association between MUFA15 and hypertension was interacted by MUFA17, and the association between MUFA20 and hypertension was interacted by MUFA18. The mediation effects of body mass index and waist circumference were found on associations of hypertension with MUFA15, MUFA17 and MUFA20. Our findings suggested that associations with hypertension were different among individual MUFAs, and mutual interactions existed, implying that the utility of individual MUFAs might be recommended for estimating relationships between MUFAs and diseases. Moreover, fat accumulation might potentially underlie associations between MUFAs and hypertension.

The Role of Oxidative Stress in Hypertension: The Insight into Antihypertensive Properties of Vitamins A, C and E

Hypertension stands as a pervasive global health challenge, contributing significantly to mortality rates worldwide. Various factors, including lifestyle choices and dietary habits, contribute to the development of hypertension. In recent years, oxidative stress has garnered significant attention as a factor influencing hypertension risk, prompting a shift in research focus towards exploring it as a potential target for prevention and treatment. Antioxidants found in our diet, such as vitamins C, E and carotenoids exhibit the ability to neutralize reactive oxygen species, thereby mitigating oxidative stress. In addition, Vitamin A has an antioxidant effect despite not being an antioxidant itself. Consequently, supplementation or increased intake of these antioxidants has been hypothesized to potentially lower blood pressure levels and aid in the management of hypertension, thereby potentially prolonging life expectancy. Research findings regarding this effect have been diverse. This paper examines the existing literature demonstrating favorable outcomes associated with antioxidant supplementation.

Association of oxidative balance score with chronic kidney disease: NHANES 1999-2018

Background

The Oxidative Balance Score (OBS), which quantifies the balance between antioxidants and pro-oxidants influenced by diet and lifestyle, is crucial given oxidative stress's significant role in Chronic Kidney Disease (CKD). This study aims to determine the association between OBS and CKD using data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018.

Methods

We analyzed data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. OBS was constructed from a detailed array of 20 factors, including dietary nutrients and lifestyle behaviors. The relationship between OBS and CKD risk was evaluated using weighted logistic regression models, adjusted for potential confounders, with a generalized additive model (GAM) examining non-linear associations. Subgroup analyses and interaction effects across diverse demographic and clinical groups, along with sensitivity analyses, were performed to validate the findings.

Results

Among 32,120 participants analyzed, 4,786 were identified with CKD. Fully adjusted weighted logistic regression analysis revealed that each unit increase in OBS was associated with a 2% reduction in CKD prevalence [OR: 0.98 (0.98-0.99), P < 0.001]. Higher OBS quartiles were significantly correlated with a decreased CKD risk [Q4 vs. Q1: OR: 0.82 (0.68-0.98), P = 0.03; P for trend = 0.01]. The GAM and smoothed curve fit indicated a linear relationship between OBS and the risk of CKD. Stratified and sensitivity analyses further substantiated the inverse relationship between OBS and CKD prevalence.

Conclusions

Our findings from the NHANES data affirm a significant inverse association between OBS and CKD risk in the U.S. population, underscoring the role of optimizing dietary and lifestyle factors in managing CKD risk. These results advocate for incorporating OBS considerations into CKD prevention and treatment strategies.

Association of composite dietary antioxidant index with mortality in adults with hypertension: evidence from NHANES

Objective

The objective of this study is to assess the correlation between composite dietary antioxidant index (CDAI) with all-cause mortality and cause-specific mortality in adults with hypertension.

Methods

The cohort study comprised adult participants with hypertension from the NHANES database, spanning 9 cycles from 2001 to 2018. Follow-up was conducted until December 31, 2019. Multi-variable Cox regression analysis was utilized to ascertain hazard ratios (HR) and their corresponding 95% confidence intervals, evaluating the relationship between CDAI and the risks of all-cause and cause-specific mortality. To further investigate the association between CDAI and mortality rates in adults with hypertension, Kaplan-Meier survival curves, restricted cubic splines (RCS), subgroup analyses and sensitivity analyses were employed.

Results

The analysis included 16,713 adults with hypertension (mean age 56.93 ± 0.23 years, 8,327 [49.61%] male). During the mean follow-up time 102.11 ± 1.22 months, with 3,908 (18.08%) all-cause mortality occurred, 1,082 (4.84%) cardiovascular mortality and 833 (3.80%) cancer mortality. Compared to the lowest quartile of CDAI, the weighted multivariate hazard ratios of participants in the highest quartile was 0.77 (95% CI, 0.68-0.87) for all-cause mortality, 0.83 (95% CI, 0.67-1.04) for cardiovascular mortality, and 0.64 (95% CI, 0.50-0.82) for cancer mortality. RCS analysis demonstrated a nonlinear association of CDAI with all-cause and cancer mortality, and a linear association between CDAI and cardiovascular mortality. The results were robust in subgroup analyses and sensitivity analyses.

Conclusion

Higher CDAI is associated with reduced all-cause mortality, cardiovascular mortality, and cancer mortality in hypertensive adults. Our findings highlight the importance of an antioxidant diet in improving outcomes in adults with hypertension.

A cross-sectional study exploring the relationship between oxidative balance score and 10-year atherosclerotic cardiovascular disease risk based on the National Health and Nutrition Examination Survey (2011-2020)

BACKGROUND

The intricate interaction between oxidative stress and atherosclerotic cardiovascular disease (ASCVD) is an essential area of research because of the potential role of oxidative homeostasis in regulating ASCVD risk. This study aimed to investigate the relationship between the oxidative balance score (OBS) and the 10-years risk of ASCVD to gain insight into how oxidative balance affects cardiovascular health.

METHODS

This cross-sectional study analyzed National Health and Nutrition Examination Survey (NHANES) 2011-2020 data (40-79 age group), exploring OBS's link to 10-years ASCVD risk. OBS categorized dietary and lifestyle factors. Multivariate logistic regression controlled for age, sex, race, and demographics. A restricted cubic spline examined linear relationships; robustness was ensured through subgroup analyses.

RESULTS

Analysis of 4955 participants reveals a negative association between OBS and 10-years ASCVD risk. Continuous OBS adjusted OR: 0.97 (95% CI: 0.95∼0.99, p < .001). Quartile analysis shows reduced risk in Q2 0.88 (95% CI: 0.63∼1.22, p = .43), Q3 0.92 (95% CI: 0.66∼1.28, p = .614), and Q4 0.59 (95% CI: 0.42∼0.83, p = .002) compare Q1. Quartile analysis indicated decreasing risk in higher OBS quartiles. Lifestyle OBS and Dietary OBS demonstrated similar trends. Stratified analyses highlight race and hypertension as effect modifiers (p < .05).

CONCLUSION

Our study suggests an association between higher OBS and a reduced 10-years ASCVD risk. However, causation should not be inferred, and in the future, more extensive clinical and fundamental research is required to delve deeper into this association.

Effect of vitamin B2, vitamin C, vitamin D, vitamin E and folic acid in adults with essential hypertension: a systematic review and network meta-analysis

OBJECTIVES

The objective of the current study is to compare the treatment effects of different vitamins on essential hypertension to provide an initial basis for developing evidence-based practices.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Five electronic databases (PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov) were searched from their inception to 25 September 2023.

OUTCOMES

The primary outcomes were the difference between the intervention group and the control group in changes in office systolic blood pressure (SBP) and office diastolic blood pressure (DBP) from baseline. The secondary outcomes were the difference between the intervention group and the control group in changes in 24-hour mean ambulatory systolic blood pressure (24 hours SBP), 24-hour mean ambulatory diastolic blood pressure (24 hours DBP) and heart rate (HR) from baseline.

RESULTS

A total of 23 studies comparing five vitamins (vitamin B2, vitamin C, vitamin D, vitamin E, folic acid) and involving 2218 participants were included. The included trials were all vitamin versus placebo, so the network was star-shaped. Among the five vitamins, only vitamin E was significantly more effective at reducing SBP (mean difference: -14.14 mm Hg, 95% credible intervals: -27.62 to -0.88) than placebo. In addition, no evidence was found that any of the five vitamins influenced DBP, 24 hours SBP, 24 hours DBP, or HR. The dose of vitamins, geographical region and percentage of males (only SBP) might be sources of heterogeneity. Sensitivity and subgroup analysis revealed that the effect of vitamin intervention on blood pressure varies according to different doses of vitamins.

CONCLUSIONS

According to the results, vitamin E might be an effective measure to reduce SBP, but more research is needed to validate this finding.

PROSPERO REGISTRATION NUMBER

CRD42022352332.

The combined effects of overweight/obesity and dietary antioxidant quality score on hypertension in children and adolescents

BACKGROUND

This study was to evaluate the combined effects of overweight/obesity and DAQS on the risk of hypertension in children and adolescents.

METHODS

In this cross-sectional study, the data of 14,316 subjects were extracted from the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression analysis was used to explore the associations of obesity and DAQS with the risk of hypertension. The combined effect of overweight/obesity and DAQS on the risk of hypertension was evaluated.

RESULTS

Body mass index (BMI)-for-age < 85th percentile was associated with reduced risk of hypertension in children and adolescents [odds ratio (OR) = 0.48, 95% confidence interval (CI): 0.41-0.62]. No significant association between DAQS ≥ 3 and the risk of hypertension before and after the adjustment of confounders (P > 0.05). Subjects with BMI-for-age of < 85th percentile and DAQS < 3 was associated with decreased risk of hypertension (OR = 0.53, 95%CI: 0.35-0.79). People with BMI-for-age of < 85th percentile and DAQS ≥ 3 was correlated with decreased risk of hypertension (OR = 0.52, 95%CI: 0.36-0.74). Subgroup analysis revealed that in subjects aged ≥ 12 years, decreased risk of hypertension was observed in BMI-for-age < 85th percentile and DAQS < 3 group (OR = 0.48, 95%CI: 0.31-0.73) as well as BMI-for-age < 85th percentile and DAQS ≥ 3 group (OR = 0.47, 95%CI: 0.32-0.67). In boys, BMI-for-age < 85th percentile and DAQS < 3 group (OR = 0.45, 95%CI: 0.25-0.81) as well as BMI-for-age < 85th percentile and DAQS ≥ 3 group (OR = 0.40, 95%CI: 0.25-0.65) were correlated with decreased risk of hypertension.

CONCLUSION

Overweight/obesity and DAQS had combined effects on the risk of hypertension in children and adolescents, which implied that for children and adolescents with normal weight, to keep normal weight combined with high quality of diet might be recommended.

A causal relationship between antioxidants, minerals and vitamins and metabolic syndrome traits: a Mendelian randomization study

BACKGROUND

The available evidence regarding the association of antioxidants, minerals, and vitamins with the risk of metabolic syndrome (MetS) traits is currently limited and inconsistent. Therefore, the purpose of this Mendelian randomization (MR) study was to investigate the potential causal relationship between genetically predicted antioxidants, minerals, and vitamins, and MetS.

METHODS

In this study, we utilized genetic variation as instrumental variable (IV) to capture exposure data related to commonly consumed dietary nutrients, including antioxidants (β-carotene, lycopene, and uric acid), minerals (copper, calcium, iron, magnesium, phosphorus, zinc, and selenium), and vitamins (folate, vitamin A, B6, B12, C, D, E, and K1). The outcomes of interest, namely MetS (n = 291,107), waist circumference (n = 462,166), hypertension (n = 463,010), fasting blood glucose (FBG) (n = 281,416), triglycerides (n = 441,016), and high-density lipoprotein cholesterol (HDL-C) (n = 403,943), were assessed using pooled data obtained from the most comprehensive genome-wide association study (GWAS) available. Finally, we applied the inverse variance weighting method as the result and conducted a sensitivity analysis for further validation.

RESULTS

Genetically predicted higher iron (OR = 1.070, 95% CI 1.037-1.105, P = 2.91E-05) and magnesium levels (OR = 1.130, 95% CI 1.058-1.208, P = 2.80E-04) were positively associated with increased risk of MetS. For each component of MetS, higher level of genetically predicted selenium (OR = 0.971, 95% CI 0.957-0.986, P = 1.09E-04) was negatively correlated with HDL-C levels, while vitamin K1 (OR = 1.023, 95% CI 1.012-1.033, P = 2.90E-05) was positively correlated with HDL-C levels. Moreover, genetically predicted vitamin D (OR = 0.985, 95% CI 0.978-0.992, P = 5.51E-5) had a protective effect on FBG levels. Genetically predicted iron level (OR = 1.043, 95% CI 1.022-1.064, P = 4.33E-05) had a risk effect on TG level.

CONCLUSIONS

Our study provides evidence that genetically predicted some specific, but not all, antioxidants, minerals, and vitamins may be causally related to the development of MetS traits.

Association of gamma-tocopherol serum concentrations and blood pressure among adults in the United States: a cross-sectional study

Background

hypertension is one of the major preventable risk factors for numerous diseases. The role of vitamin E in blood pressure (BP) has been controversial. We aimed to investigate the relationship between gamma-tocopherol serum concentration (GTSC) and BP.

Methods

Data from 15,687 US adults from the National Health and Nutrition Examination Survey (NHANES) were analyzed. The correlations of GTSC with systolic BP (SBP), diastolic BP (DBP), and prevalence of hypertension were investigated by multivariate logistic regression models, generalized summation models, and fitted smoothing curves. Subgroup analyses were performed to investigate possible effect modifiers between them.

Results

With each natural log increase in GTSC, SBP, and DBP increased by 1.28 mmHg (β 1.28, 95% CI 0.71-1.84) and 1.15 mmHg (β 1.15, 95% CI 0.72-1.57), respectively, both P for trend < 0.001; the prevalence of hypertension increased by 12% (OR 1.12, 95% CI 1.03-1.22), P for trend 0.008. In subgroup analysis, in drinkers, with each natural log increase in GTSC, SBP, and DBP increased by 1.77 mmHg (β 1.77,95% CI 1.13-2.41) and 1.37 mmHg (β 1.37,95% CI 0.9-1.85), respectively, whereas they were not correlated in non-drinkers.

Conclusion

GTSC was linearly and positively associated with SBP, DBP, and the prevalence of hypertension, and alcohol consumption may modify the relationship of GTSC with SBP and DBP.

Role of Vitamins in Cardiovascular Health: Know Your Facts - Part 1

Cardiovascular (CV) disease (CVD) is a major cause of morbidity and mortality world-wide, thus it is important to adopt preventive interventions. Observational data demonstrating CV benefits of vitamin supplements, advanced by self-proclaimed experts have resulted in ~50% of Americans reporting the use of multivitamins for health promotion; this practice has led to a multi-billion-dollar business of the multivitamin-industry. However, the data on the extensive use of multivitamins show no consistent benefit for CVD prevention or all-cause mortality, while the use of certain vitamins might prove harmful. Thus, the focus of this two-part review is on the attributes or concerns about specific vitamins on CVD. In Part 1, the CV effects of specific vitamins are discussed, indicating the need for further supportive evidence of potential benefits. Vitamin A preserves CV homeostasis as it participates in many biologic functions, including atherosclerosis. However, supplementation could potentially be harmful. Betacarotene, a pro-vitamin A, conveys pro-oxidant actions that may mitigate any other benefits. Folic acid alone and certain B-vitamins (e.g., B1/B2/B6/B12) may reduce CVD, heart failure, and/or stroke, while niacin might increase mortality. Vitamin C has antioxidant and cardioprotective effects. Vitamin D may confer CV protection, but all the data are not in agreement. Combined vitamin E and C have antiatherogenic effects but clinical evidence is inconsistent. Vitamin K seems neutral. Thus, there are individual vitamin actions with favorable CV impact (certain B-vitamins and vitamins C and D), but other vitamins (β-carotene, niacin) may potentially have deleterious effects, which also holds true for high doses of fat-soluble vitamins (A/D/E/K).