A healthy dietary pattern is associated with microbiota diversity in recently diagnosed bipolar patients: The Bipolar Netherlands Cohort (BINCO) study

BACKGROUND

Diet largely impacts the gut microbiota, and may affect mental and somatic health via the gut-brain axis. As such, the relationship between diet and the microbiota in Bipolar Disorder (BD) could be of importance, but has not been studied before. The aim was therefore to assess whether dietary quality is associated with the gut microbiota diversity in patients with recently diagnosed BD, and whether changes occur in dietary quality and microbiota diversity during their first year of treatment.

METHODS

Seventy recently (<1 year) diagnosed patients with BD were included in the "Bipolar Netherlands Cohort" (BINCO), and a total of 45 participants were assessed after one year. A 203-item Food Frequency Questionnaire (FFQ) data yielded the Dutch Healthy index (DHD-15), and the microbiota composition and diversity of fecal samples were characterized by 16S rRNA gene amplicon sequencing at baseline and 1-year follow-up. Associations and changes over time were analyzed using multivariate regression analyses and t-tests for paired samples.

RESULTS

Included patients had a mean age of 34.9 years (SD ± 11.2), and 58.6 % was female. Alpha diversity (Shannon diversity index), richness (Chao1 index) and evenness (Pielou's Evenness Index) were positively associated with the DHD-15 total score, after adjustment for sex, age and educational level (beta = 0.55; P < 0.001, beta = 0.39; P = 0.024, beta = 0.54; P = 0.001 respectively). The positive correlations were largely driven by the combined positive effect of fish, beans, fruits and nuts, and inverse correlations with alcohol and processed meats. No significant changes were found in DHD-15 total score, nor in microbiota diversity, richness and evenness indexes during one year follow-up and regular treatment.

CONCLUSION

A healthy and varied diet is associated with the diversity of the microbiota in BD patients. Its potential consequences for maintaining mood stability and overall health should be studied further.

Prevalence and determinants of self-reported low-fat-, low-salt-, and vegetarian diets in patients with cardiovascular disease between 1996 and 2019

BACKGROUND AND AIMS

Guidelines no longer recommend low-fat diets and currently recommend more plant-based diets to reduce atherosclerotic cardiovascular disease (ASCVD) risk. Furthermore, these guidelines have consistently recommended salt-reduced diets. This article describes current self-reported use and time-trends in the self-reported use of low-fat, low-salt and vegetarian diets in ASCVD patients and examines patient characteristics associated with each diet.

METHODS AND RESULTS

9005 patients with ASCVD included between 1996 and 2019 in the UCC-SMART cohort were studied. The prevalence of self-reported diets was assessed and multi-variable logistic regression was used to identify the determinants of each diet. Between 1996-1997 and 2018-2019, low-fat diets declined from 22.4 % to 3.8 %, and low-salt diets from 14.7 % to 4.6 %. The prevalence of vegetarian diets increased from 1.1 % in 1996-1997 to 2.3 % in 2018-2019. Patients with cerebrovascular disease (CeVD) and peripheral artery disease or an abdominal aortic aneurysm (PAD/AAA) were less likely to report a low-salt diet than coronary artery disease (CAD) patients (OR 0.62 [95%CI 0.49-0.77] and 0.55 [95%CI 0.41-0.72]).

CONCLUSION

In the period 1996 to 2019 amongst patients with ASCVD, the prevalence of self-reported low-fat diets was low and decreased in line with changes in recommendations in major guidelines. The prevalence of self-reported vegetarian diets was low but increased in line with societal and guideline changes. The prevalence of self-reported low-salt diets was low, especially in CeVD and PAD/AAA patients compared to CAD patients, and decreased over time. Renewed action is needed to promote low-salt diets in ASCVD patients.

Diet in secondary prevention: the effect of dietary patterns on cardiovascular risk factors in patients with cardiovascular disease: a systematic review and network meta-analysis

BACKGROUND

Improving dietary habits is a first-line recommendation for patients with cardiovascular disease (CVD). It is unclear which dietary pattern most effectively lowers cardiovascular risk factors and what the short- and long-term effects are. Therefore, this network meta-analysis compared the effects of popular dietary patterns on cardiovascular risk factors in patients with established CVD.

METHODS

A systematic search of PubMed, Embase, the Cochrane library, SCOPUS and Web of Science was conducted up to 1 April 2023. Randomized controlled trials (RCTs) comparing the effect of popular dietary patterns (Mediterranean, moderate carbohydrate, low glycemic index, low-fat and minimal dietary intervention) on cardiovascular risk factors (body weight, systolic blood pressure, lipids) in CVD populations were selected. A random-effects network meta-analysis was performed.

RESULTS

Seventeen RCTs comprising 6,331 participants were included. The moderate carbohydrate diet had the most beneficial effect on body weight (-4.6 kg, 95%CrI -25.1; 15.8) and systolic blood pressure (-7.0 mmHg 95%CrI -16.8; 2.7) compared to minimal intervention. None of the included dietary patterns had a favorable effect on low-density lipoprotein cholesterol. After 12 months, the effects were attenuated compared to those at < 6 months.

CONCLUSIONS

In this network meta-analysis of 17 randomized trials, potentially clinically relevant effects of dietary interventions on CV risk factors were observed, but there was considerable uncertainty due to study heterogeneity, low adherence, or actual diminished effects in the medically treated CVD population. It was not possible to select optimal dietary patterns for secondary CVD prevention. Given recent clinical trials demonstrating the potential of dietary patterns to significantly reduce cardiovascular event risk, it is likely that these effects are effectuated through alternative physiological pathways.

Effect of dietary patterns on cardiovascular risk factors in people with type 2 diabetes. A systematic review and network meta-analysis

AIMS

To identify the most effective dietary pattern for improving cardiovascular risk factors in people with type 2 diabetes.

METHODS

PubMed, Embase, the Cochrane library, SCOPUS and Web of Science were systematically searched for randomized controlled trials comparing the effects of dietary patterns on body weight, blood pressure, HbA1c and lipids after 6 and 12 months. Treatment effects were synthesized using Bayesian network meta-analysis. Six-month changes in HbA1c, SBP and LDL-C were used to estimate relative risk reductions (RRR) for cardiovascular events.

RESULTS

Seventy-three RCTs on eight different dietary patterns were included. All reduced body weight and HbA1c after 6 months, with the largest effects from the low carbohydrate (body weight -4.8 kg, 95 %credibility interval (95 %CrI) -6.5;-3.2 kg) and Mediterranean diet (HbA1c -1.0 %, 95 %CrI -15;-0.4 % vs usual diet). There were no significant 6-month blood pressure or lipid effects. Dietary patterns had non-statistically significant 12-months effects. The Mediterranean diet resulted in the largest expected RRR for cardiovascular events: -16 % (95 %CI -31;3.0) vs usual diet.

CONCLUSIONS

In patients with type 2 diabetes, all dietary patterns outperformed usual diet in improving body weight and HbA1c after 6 months and clinically relevant cardiovascular risk reduction could be achieved. There was insufficient evidence to select one optimal dietary pattern.

Metabolic syndrome and heart failure: 40 years follow up results of the Seven Countries Study

Introduction

Metabolic syndrome (Met Sy) as a highly debatable cluster of traditional risk factors is known to promote cardiometabolic-related morbidity and mortality, but its precise mechanisms remain to be determined.

Purpose

We sought to determine influence of MetSy on heart failure (HF) morbidity and mortality in the Seven Countries' Study as one of the oldest epidemiological studies.

Methods

The Seven Countries Study encompassed 12,763 participants from 3 continents who were all healthy men of over 40 years at baseline and who underwent regular check ups every 5 years throughout over a 4 decades' span. Morbidity and mortality was adjudicated according to valid ICD and LPH coding.

Results

Using the IDF definition of the Metabolic Syndrome, 9,09% of participants were identified (Figure 1). HF was confirmed in 220 patients (16.4% alive at 40y follow up visit), while 8.2% died of HF as well in the same time-frame (Tables 1 & 2). Presence of MetSy has been shown to significantly influence HF mortality (Figures 2) with lowest survival of 22% for 300 months of follow up for patients with both MetSy and HF (Log rank test=4.405, p&lt;0.0001).

Conclusion

Metabolic syndrome treatment remains in the realm of risk factors' control that now we know influence both ischemic heart disease and heart failure of other origins. Historically, just emerging biomarkers' and targeted imaging weren't available to determine such at the time of HF diagnosis. Also, the sample consisted of men only, mainly Caucasian and a modest proportion of Asian and African-American now known to carry ethnic-specific burden of cardiovascular disease. All of the above, emphasizes the importance of more diversity, equity and inclusion-dedicated long term both observational, as well as interventional research.

Funding Acknowledgement

Type of funding sources: None.

Effect of diet and lifestyle on the relationship between body mass index and waist circumference and cardiovascular mortality in myocardial infarction patients from the Alpha Omega Cohort

Introduction

The associations between measures of body adiposity body mass index (BMI) and waist circumference (WC) and cardiovascular disease (CVD) mortality have been frequently studied and usually follow a J-shaped curve or show a positive relationship. However, less is known about the influence of diet and physical activity on these associations.

Purpose

We aimed to gain insight in potential lifestyle-related effect modifiers of the association of BMI and WC with CVD mortality in myocardial infarction (MI) patients.

Methods

We included 4,837 Dutch patients from the Alpha Omega Cohort with a MI &lt;10 y prior enrolment. BMI and WC were assessed at baseline (2002–2006). Patients were followed through December 2018 for vital status and cause-specific mortality. Continuous associations of BMI and WC with CVD mortality were estimated using Cox proportional hazards models with restricted cubic splines. A BMI of 25 kg/m2 and a WC of 100 cm were used as the references. Age and sex adjusted associations were stratified for diet quality and physical activity level and interaction terms were calculated.

Results

Of the study population (69.0±5.6 y), 17% smoked, 21% had diabetes, 22% were female and &gt;85% used any type of cardiovascular medication. During a median follow-up of 12.4 years [8.5–13.8], 1,010 deaths occurred due to CVD. A J-shaped continuous association was observed between BMI and CVD mortality with inverse associations for a BMI between 25–30 kg/m2, compared to 25 kg/m2. The nadir (HR, 95% CI) was 27.4 kg/m2 (HR: 0.94, 95% CI: 0.88, 1.00) (A). For WC, a non-linear association was observed with CVD mortality with higher mortality risks for a WC above 100 cm (A). Results were similar in patients with low versus high diet quality and in patients with low versus high physical activity (B), interaction terms were not significant (all p&gt;0.55).

Conclusion

In MI patients, a BMI between 25–30 kg/m2 was associated with the lowest risk of CVD mortality. A WC above 100 cm was associated with a higher CVD mortality risk. The observed associations manifested independently of diet quality and physical activity level. Therefore, body adiposity seems to determine CVD mortality risk independently of underlying lifestyle factors.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Regio Deal Foodvalley

Metabolic Age Based on the BBMRI-NL 1H-NMR Metabolomics Repository as Biomarker of Age-related Disease

BACKGROUND

The blood metabolome incorporates cues from the environment and the host's genetic background, potentially offering a holistic view of an individual's health status.

METHODS

We have compiled a vast resource of proton nuclear magnetic resonance metabolomics and phenotypic data encompassing over 25 000 samples derived from 26 community and hospital-based cohorts.

RESULTS

Using this resource, we constructed a metabolomics-based age predictor (metaboAge) to calculate an individual's biological age. Exploration in independent cohorts demonstrates that being judged older by one's metabolome, as compared with one's chronological age, confers an increased risk on future cardiovascular disease, mortality, and functionality in older individuals. A web-based tool for calculating metaboAge (metaboage.researchlumc.nl) allows easy incorporation in other epidemiological studies. Access to data can be requested at bbmri.nl/samples-images-data.

CONCLUSIONS

In summary, we present a vast resource of metabolomics data and illustrate its merit by constructing a metabolomics-based score for biological age that captures aspects of current and future cardiometabolic health.

Diet and Kidney Function: a Literature Review

PURPOSE OF REVIEW

The burden of chronic kidney disease (CKD) is increasing worldwide. For CKD prevention, it is important to gain insight in commonly consumed foods and beverages in relation to kidney function.

RECENT FINDINGS

We included 21 papers of prospective cohort studies with 3-24 years of follow-up. We focused on meat, fish, dairy, vegetables, fruit, coffee, tea, soft drinks, and dietary patterns. There was convincing evidence that a healthy dietary pattern may lower CKD risk. Plant-based foods, coffee, and dairy may be beneficial. Unhealthy diets and their components, such as red (processed) meat and sugar-sweetened beverages, may promote kidney function loss. For other foods and beverages, associations with CKD were neutral and/or the number of studies was too limited to draw conclusions. Healthy dietary patterns are associated with a lower risk of CKD. More research is needed into the effects of specific food groups and beverages on kidney function.

Circulating n-3 fatty acids and linoleic acid as indicators of dietary fatty acid intake in post-myocardial infarction patients

BACKGROUND AND AIMS

Population-based studies often use plasma fatty acids (FAs) as objective indicators of FA intake, especially for n-3 FA and linoleic acid (LA). The relation between dietary and circulating FA in cardiometabolic patients is largely unknown. We examined whether dietary n-3 FA and LA were reflected in plasma lipid pools in post-myocardial infarction (MI) patients.

METHODS AND RESULTS

Patients in Alpha Omega Cohort filled out a 203-item food-frequency questionnaire from which eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), and LA intake were calculated. Circulating individual FA (% total FA) were assessed in cholesteryl esters (CE; n = 4066), phospholipids (PL; n = 838), and additionally in total plasma for DHA and LA (n = 739). Spearman correlation coefficients (r_s) were calculated for dietary vs. circulating FA. Circulating FA were also compared across dietary FA quintiles, overall and in subgroups by sex, obesity, diabetes, statin use, and high alcohol intake. Patients were on average 69 years old and 79% was male. Moderate correlations between dietary and circulating levels were observed for EPA (r_s∼0.4 in CE and PL) and DHA (r_s ∼0.5 in CE and PL, ∼0.4 in total plasma), but not for ALA (r_s ∼0.0). Weak correlations were observed for LA (r_s 0.1 to 0.2). Plasma LA was significantly lower in statin users and in patients with a high alcohol intake.

CONCLUSIONS

In post-MI patients, dietary EPA and DHA were well reflected in circulating levels. This was not the case for LA, which may partly be influenced by alcohol use and statins.

Potassium supplementation and heart rate: A meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Increasing the intake of potassium has been shown to lower blood pressure, but whether it also affects heart rate (HR) is largely unknown. We therefore assessed the effect of potassium supplementation on HR in a meta-analysis of randomized controlled trials.

METHODS AND RESULTS

We searched PubMed (1966-October 2014) for randomized, placebo-controlled trials in healthy adults with a minimum duration of two weeks in which the effect of increased potassium intake on HR was assessed. In addition, reference lists from meta-analysis papers on potassium and blood pressure were hand-searched for publications. Two investigators independently extracted the data. We performed random effects meta-analyses, subgroup and meta-regression analyses for characteristics of the study (e.g. design, intervention duration, potassium dose and salt type, change in potassium excretion, sodium excretion during intervention) and study population (e.g. gender, age, hypertensive status, pre-study HR, pre-study potassium excretion). A total of 22 trials (1086 subjects), with a median potassium dose of 2.5 g/day (range: 0.9-4.7 g/day), and median intervention duration of 4 weeks (range: 2-24 weeks) were included. The meta-analysis showed no overall effect of increased potassium intake on HR (0.19 bpm, 95% CI: -0.44, 0.82). Stratified analyses yielded no significant effects of potassium intake on HR in subgroups, and there was no evidence for a dose-response relationship in meta-regression analyses.

CONCLUSION

A chronic increase in potassium intake with supplemental doses of 2-3 g/day is unlikely to affect HR in apparently healthy adults.

Arterial stiffness is not associated with bone parameters in an elderly hyperhomocysteinemic population

Several studies have observed positive associations between bone disease and cardiovascular disease. A potential common pathway is hyperhomocysteinemia; however, to date, there is a lack of data regarding hyperhomocysteinemic populations. Therefore, we examined both cross-sectionally and longitudinally, whether there is an association between bone parameters and arterial stiffness in a hyperhomocysteinemic population, and investigated the potential common role of homocysteine (hcy) level on these associations. Cross-sectional and longitudinal data of the B-PROOF study were used (n = 519). At both baseline and 2-year follow-up we determined bone measures-incident fractures and history of fractures, bone-mineral density (BMD) and quantitative ultrasound (QUS) measurement. We also measured arterial stiffness parameters at baseline-pulse wave velocity, augmentation index and aortic pulse pressure levels with applanation tonometry. Linear regression analysis was used to examine these associations and we tested for potential interaction of hcy level. The mean age of the study population was 72.3 years and 44.3 % were female. Both cross-sectionally and longitudinally there was no association between arterial stiffness measures and BMD or QUS measurements or with incident fractures (n = 16) within the 2-3 years of follow-up. Hcy level did not modify the associations and adjustment for hcy did not change the results. Arterial stiffness was not associated with bone parameters and fractures, and hcy neither acted as a pleiotropic factor nor as a mediator. The potential association between bone and arterial stiffness is therefore not likely to be driven by hyperhomocysteinemia.

Physical Fitness, Activity and Hand-Grip Strength Are Not Associated with Arterial Stiffness in Older Individuals

OBJECTIVES

Whereas evidence exists about the benefits of intensive exercise on cardiovascular outcomes in older adults, data are lacking regarding long-term effects of physical fitness and physical activity on cardiovascular health. Therefore, we aimed to investigate the longitudinal association of physical fitness, physical activity and muscle strength with arterial stiffness measures.

DESIGN

a longitudinal follow-up study (2 years) of data from the B-PROOF study.

SETTING

a subgroup of the B-PROOF study (n=497).

PARTICIPANTS

Four hundred ninety-seven participants with a mean age of 72.1 years (SD 5.4) of which 57% was male.

MEASUREMENTS

All performed at baseline and after two-year follow-up. Arterial stiffness was estimated by pulse wave velocity (PWV) measured with applanation tonometry. Furthermore, augmentation index (AIx) and aortic pulse pressure (PP) were assessed. Physical activity was estimated using a validated questionnaire regarding daily activities. Physical fitness was measured with a physical performance score, resulting from a walking, chair-stand and balance test. Muscle strength was assessed with hand-grip strength using a handheld dynamometer.

RESULTS

The median performance score was 9.0 [IQR 8.0-11.0], the mean physical activity was 744.4 (SD 539.4) kcal/day and the mean hand-grip strength was 33.1 (SD 10.2) kg. AIx differed between the baseline and follow-up measurement (26.2% (SD 10.1) vs. 28.1% (SD 9.9); p < 0.01), whereas PWV and aortic PP did not. In multivariable linear regression analysis, physical performance, physical activity and hand-grip strength at baseline were not associated with the amount of arterial stiffness after two years of follow-up.

CONCLUSION

Physical fitness, activity and muscle strength were not associated with arterial stiffness. More research is warranted to elucidate the long-term effects of daily and intensive physical activity on arterial stiffness in an elderly population.

Effects of sodium and potassium supplementation on blood pressure and arterial stiffness: a fully controlled dietary intervention study

We performed a randomised, placebo-controlled, crossover study to examine the effects of sodium and potassium supplementation on blood pressure (BP) and arterial stiffness in untreated (pre)hypertensive individuals. During the study, subjects were on a fully controlled diet that was relatively low in sodium and potassium. After a 1-week run-in period, subjects received capsules with supplemental sodium (3 g d(-1), equals 7.6 g d(-1) of salt), supplemental potassium (3 g d(-1)) or placebo, for 4 weeks each, in random order. Fasting office BP, 24-h ambulatory BP and measures of arterial stiffness were assessed at baseline and every 4 weeks. Of 37 randomized subjects, 36 completed the study. They had a mean pre-treatment BP of 145/81 mm Hg and 69% had systolic BP ⩾140 mm Hg. Sodium excretion was increased by 98 mmol per 24 h and potassium excretion by 63 mmol per 24 h during active interventions, compared with placebo. During sodium supplementation, office BP was significantly increased by 7.5/3.3 mm Hg, 24-h BP by 7.5/2.7 mm Hg and central BP by 8.5/3.6 mm Hg. During potassium supplementation, 24-h BP was significantly reduced by 3.9/1.6 mm Hg and central pulse pressure by 2.9 mm Hg. Pulse wave velocity and augmentation index were not significantly affected by sodium or potassium supplementation. In conclusion, increasing the intake of sodium caused a substantial increase in BP in subjects with untreated elevated BP. Increased potassium intake, on top of a relatively low-sodium diet, had a beneficial effect on BP. Arterial stiffness did not materially change during 4-week interventions with sodium or potassium.

Fish and omega-3 fatty acid intake in relation to circulating fibroblast growth factor 23 levels in renal transplant recipients

BACKGROUND AND AIMS

A high circulating fibroblast growth factor 23 (FGF23) level is an independent risk factor for cardiovascular mortality in renal transplant recipients and the general population. N-3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) may contribute to cardiovascular risk reduction. We investigated whether fish and EPA-DHA intake are related to FGF23 levels in renal transplant recipients.

METHODS AND RESULTS

We performed a cross-sectional analysis in 619 stable renal transplant recipients (mean age 53 years, 57% male, estimated glomerular filtration rate [eGFR] 53 ± 20 mL/min/1.73 m(2)). Dietary intake was assessed by a 177-item food frequency questionnaire. Serum intact FGF23 was measured by ELISA. We examined differences in FGF23 levels across categories of fish and EPA-DHA intake using analysis of variance models adjusted for age, sex, dietary and lifestyle factors and key determinants of FGF23. Patients consumed on average 15 g of fish and 139 mg EPA-DHA/day. Median FGF23 was 62 pg/mL (IQR 43-98 pg/mL). Higher dietary EPA-DHA and fish intake were associated with lower serum FGF23 levels. Subgroup analyses revealed that particularly in patients with reduced renal function (eGFR <60 mL/min/1.73 m(2)), adjusted FGF23 levels (114, 79, 75 pg/mL, P = 0.0001) were inversely associated with tertiles of EPA-DHA intake. Similarly, we observed an inverse association between fish consumption and serum FGF23 levels in adjusted analyses.

CONCLUSION

A higher intake of fish and dietary n-3 fatty acids (EPA-DHA) is related to lower circulating FGF23 levels in renal transplant recipients. Further research is needed to assess the causality of this association and the clinical implications.

Associations of plant and animal protein intake with 5-year changes in blood pressure: the Zutphen Elderly Study

BACKGROUND AND AIM

The aim of the present study was to investigate the association of plant and animal protein intake with 5-year changes in blood pressure (BP) level.

METHODS AND RESULTS

Analyses were based on 702 observations of 272 men participating in the Zutphen Elderly Study. Men did not use antihypertensive medication and were initially free of cardiovascular disease, diabetes mellitus and cancer. Physical and dietary examinations were performed in 1985, 1990, 1995, and 2000. Diet was assessed using the cross-check dietary history method. Men were categorised into tertiles according to their plant and animal protein intake. BP was measured twice at each examination. The associations of plant and animal protein intake with 5-year changes in BP level were investigated by a random intercept model with first-order autoregressive (AR [1]) serial correlation and a nugget effect. Adjustments were made for age, examination year, BMI, socioeconomic status, smoking, physical activity, prescribed diet, alcohol consumption and intake of energy and nutrients. In 1985, men were 70.1 ± 4.6 years old and had a mean BP of 147/84 mmHg. Mean protein intake was 15 en%, of which one-third consisted of plant protein. The higher-intake tertiles of plant protein intake were associated with a mean 5-year change of -2.9 mmHg (95% CI: -5.6, -0.2) systolic and -1.7 mmHg (95% CI: -3.2, -0.2) diastolic, compared with the lowest-intake tertile. No associations were observed for animal protein intake.

CONCLUSION

Intake of plant protein, but not animal protein, was inversely associated with 5-year changes in BP level in elderly men.

B-vitamin levels and genetics of hyperhomocysteinemia are not associated with arterial stiffness

BACKGROUND AND AIMS

Hyperhomocysteinemia is associated with arterial stiffness, but underlying pathophysiological mechanisms explaining this association are to be revealed. This study was aimed to explore two potential pathways concerning the one-carbon metabolism. A potential causal effect of homocysteine was explored using a genetic risk score reflecting an individual's risk of having a long-term elevated plasma homocysteine level and also associations with B-vitamin levels were investigated.

METHODS AND RESULTS

Baseline cross-sectional data of the B-PROOF study were used. In the cardiovascular subgroup (n = 567, 56% male, age 72.6 ± 5.6 yrs) pulse wave velocity (PWV) was determined using applanation tonometry. Plasma concentrations of vitamin B12, folate, methylmalonic acid (MMA) and holo transcobalamin (holoTC) were assessed and the genetic risk score was based on 13 SNPs being associated with elevated plasma homocysteine. Associations were examined using multivariable linear regression analysis. B-vitamin levels were not associated with PWV. The genetic risk score was also not associated with PWV. However, the homocysteine-gene interaction was significant (p < 0.001) in the association of the genetic risk score and PWV. Participants with the lowest genetic risk of having long-term elevated homocysteine levels, but with higher measured homocysteine levels, had the highest PWV levels.

CONCLUSION

Homocysteine is unlikely to be causally related to arterial stiffness, because there was no association with genetic variants causing hyperhomocysteinemia, whereas non-genetically determined hyperhomocysteinemia was associated with arterial stiffness. Moreover, the association between homocysteine and arterial stiffness was not mediated by B-vitamins. Possibly, high plasma homocysteine levels reflect an unidentified factor, that causes increased arterial stiffness.

Dairy product intake in relation to glucose regulation indices and risk of type 2 diabetes

BACKGROUND AND AIM

A high intake of dairy has been linked to lower risk of type 2 diabetes (T2D). The relationship between dairy intake and glucose metabolism is still not well understood. The aim of this study was to investigate the relation between the intake of total dairy and dairy subgroups and T2D and measures of glucose metabolism.

METHODS AND RESULTS

A total of 5953 Danish men and women aged 30-60 years without baseline diabetes or cardiovascular diseases were included in this prospective analysis. The dairy intake at baseline was categorised into low-fat dairy, full-fat dairy, milk and milk products, cheese and fermented dairy. Fasting plasma glucose (FPG), 2-h plasma glucose (2hPG), HbA1c, insulin resistance (HOMA2-IR) and beta-cell function (HOMA2-B) were considered at 5-year follow-up. In the maximally-adjusted model (demographics, lifestyle factors, dietary factors and waist), cheese intake was inversely associated with 2hPG (β = -0.048, 95% CI -0.095; -0.001). Fermented dairy intake was inversely associated with FPG (β = -0.028, 95% CI -0.048; -0.008) and HbA1c (β = -0.016, 95% CI -0.030; -0.001). Total dairy intake and the dairy subgroups were not related to HOMA-IR and HOMA-B in the maximally-adjusted model. Furthermore, there was no significant association between intake of total dairy or any of the dairy subgroups and incidence of T2D.

CONCLUSION

Our data suggest a modest beneficial effect of cheese and fermented dairy on glucose regulation measures; however, this did not translate into a significant association with incident T2D.

N-6 and n-3 fatty acid cholesteryl esters in relation to incident stroke in a Dutch adult population: a nested case-control study

BACKGROUND AND AIMS

There are few prospective studies on fatty acid status in relation to incident stroke, with inconsistent results. We assessed the associations of plasma n-6 and n-3 PUFA in cholesteryl esters with the risk of total stroke and stroke subtypes in Dutch adults.

METHODS AND RESULTS

We conducted a nested case-control study using data from a population-based cohort study in adults aged 20-65 years. Blood sampling and data collection took place during 1993-1997 and subjects were followed for 8-13 years. We identified 179 incident cases of stroke and 179 randomly selected controls, matched on age, gender, and enrollment date. Odds ratios (OR) with 95% confidence intervals (95%CI) were calculated per standard deviation (SD) increase of PUFA in cholesteryl esters using multivariable conditional logistic regression. Cases comprised 93 ischemic, 50 hemorrhagic, and 36 unspecified strokes. The n-6 PUFA linoleic acid and arachidonic acid contributed ~55% and ~6.5% respectively to total plasma fatty acids, whereas the n-3 PUFA alpha-linolenic acid contributed ~0.5% and eicosapentaenoic acid plus docosahexaenoic acid (EPA-DHA) ~1.3%. After adjustment for confounders, n-6 and n-3 PUFA were not associated with incident total stroke or stroke subtypes. The OR (95% CI) for total stroke was 0.95 (0.74-1.23) per SD increase in linoleic acid and 1.02 (0.80-1.30) per SD increase in arachidonic acid. ORs (95% CI) for total stroke were 0.94 (0.72-1.21) for alpha-linolenic acid and 1.16 (0.94-1.45) for EPA-DHA.

CONCLUSION

In the present study, plasma n-6 or n-3 fatty acids were not related to incident stroke or stroke subtypes.

Cardiovascular risk management of hypertension and hypercholesterolaemia in the Netherlands: from unifactorial to multifactorial approach

About 30 years ago, the first Dutch unifactorial guidelines on hypertension and hypercholesterolaemia were developed. These guidelines have been revised several times, often after publication of landmark studies on new generations of drugs. In 1978, cut-off points for pharmacological treatment of hypertension were based on diastolic blood pressure values ≥115 mmHg, and in 2000 they were lowered to >100 mmHg. From 1997 onwards, cut-off points for systolic blood pressure values >180 mmHg were introduced, which became leading. In 1987, cut-offs for hypercholesterolaemia of ≥8 mmol/l were set and from 2006 pharmacological treatment was based on a total/HDL cholesterol ratio >8. Around 2000, treatment decisions for hypertension and/or hypercholesterolaemia were no longer based on high levels of individual risk factors, but on a multifactorial approach based on total risk of cardiovascular diseases (CVD), determined by a risk function. In the 2006 multidisciplinary guideline on cardiovascular risk management, the Framingham risk tables were replaced by European SCORE risk charts. A cut-off point of 10% CVD mortality was set in the Netherlands. In 2011, this cut-off point changed to 20% fatal plus nonfatal CVD risk. Nowadays, 'the lower the risk factors, the lower the absolute risk' is the leading paradigm in CVD prevention.

No effects of n-3 fatty acid supplementation on serum total testosterone levels in older men: the Alpha Omega Trial

The intake of the n-3 fatty acids alpha-linolenic acid (ALA), acid (EPA) and docosahexaenoic acid (DHA) has been related to testosterone levels in epidemiological analyses. The aim of this study was to assess whether the n-3 fatty acids affects testosterone levels in post-myocardial infarction (MI) patients, who are at risk of testosterone deficiency. In a double-blind, placebo-controlled trial of low-dose supplementation of n-3 fatty acids, we included 1850 male post-MI patients aged 60-80 years who participated in the Alpha Omega Trial. Patients were randomly allocated to margarines that provided 400 mg/day of EPA-DHA (n = 453), 2 mg/day of ALA (n = 467), EPA-DHA plus ALA (n = 458), or placebo (n = 472). Serum testosterone levels were assessed at baseline and after 41 months using whole day blood samples obtained at the subjects' home or at the hospital. Subjects were on average age of 68.4 (SD 5.3) years old and had baseline mean serum total testosterone of 14.8 (SD 5.6) nmol/L. The four randomized groups did not differ for baseline characteristics. ALA, EPA-DHA, and EPA-DHA plus ALA supplementation did not affect serum total testosterone compared to placebo. Moreover, n-3 fatty acid supplementation did not affect the risk of incident testosterone deficiency (n = 76 with total testosterone <8.0 nmol/L). We conclude that n-3 fatty acids supplementation did not affect serum total testosterone in men who had had a MI.

Levels and trends in cardiovascular risk factors and drug treatment in 4837 elderly Dutch myocardial infarction patients between 2002 and 2006

BACKGROUND: It is important to gain insight into opportunities for secondary prevention of cardiovascular disease. Our aim was to investigate levels and trends in cardiovascular risk factors and drug treatment in Dutch post-myocardial infarction (MI) patients between 2002 and 2006 and to make comparisons with the EUROASPIRE surveys (1999-2007). METHODS: We analysed data from 4837 post-MI patients (aged 69 years, 78% men) from 32 Dutch hospitals, using baseline cross-sectional data from the Alpha Omega Trial. RESULTS: Between 2002 and 2006, significant declines were found in the prevalence of smoking (23% to 16%, p < 0.001), hypercholesterolaemia (≥5 mmol/l; 54% to 27%, p < 0.0001) and hypertension (≥140/90 mmHg; 58% to 48%, p < 0.001). The prevalence of antithrombotic drugs was high (97%). The prevalence of lipid-modifying drugs and antihypertensives was high, and increased (74% to 90%, p < 0.0001 and 82% to 93%, p < 0.001, respectively). The prevalence of obesity (27%) was high in 2002 and decreased to 24% in 2006, albeit not significantly. Diabetes prevalence was high and increased between 2002 and 2006 (18% to 22%, p = 0.02). In comparison with EUROASPIRE patients, who were on average 8-10 years younger, our study in 2006 included patients with lower levels of obesity, hypertension, hypercholesterolaemia, diabetes and lower use of antiplatelets and β-blockers, but similar levels of lipid-modifying drugs. CONCLUSIONS: This study showed that older Dutch post-MI patients were adequately treated with drugs, and that risk factors reached lower levels than in the younger EUROASPIRE patients. However, there is room for improvement in diet and lifestyle, given the high prevalence of smoking, obesity, and diabetes.

A high menaquinone intake reduces the incidence of coronary heart disease

BACKGROUND AND AIM

Vitamin K dependent proteins have been demonstrated to inhibit vascular calcification. Data on the effect of vitamin K intake on coronary heart disease (CHD) risk, however, are scarce. To examine the relationship between dietary vitamins K(1) and K(2) intake, and its subtypes, and the incidence of CHD.

METHODS AND RESULTS

We used data from the Prospect-EPIC cohort consisting of 16,057 women, enrolled between 1993 and 1997 and aged 49-70 years, who were free of cardiovascular diseases at baseline. Intake of vitamin K and other nutrients was estimated with a food frequency questionnaire. Multivariate Cox proportional hazards models were used to analyse the data. After a mean+/-SD follow-up of 8.1+/-1.6 years, we identified 480 incident cases of CHD. Mean vitamin K(1) intake was 211.7+/-100.3 microg/d and vitamin K(2) intake was 29.1+/-12.8 microg/d. After adjustment for traditional risk factors and dietary factors, we observed an inverse association between vitamin K(2) and risk of CHD with a Hazard Ratio (HR) of 0.91 [95% CI 0.85-1.00] per 10 microg/d vitamin K(2) intake. This association was mainly due to vitamin K(2) subtypes MK-7, MK-8 and MK-9. Vitamin K(1) intake was not significantly related to CHD.

CONCLUSIONS

A high intake of menoquinones, especially MK-7, MK-8 and MK-9, could protect against CHD. However, more research is necessary to define optimal intake levels of vitamin K intake for the prevention of CHD.

Blood pressure response to calcium supplementation: a meta-analysis of randomized controlled trials

Calcium plays a role in blood pressure (BP) regulation, but the importance of supplemental calcium intake for the prevention of hypertension is still debated. We conducted a meta-analysis of randomized controlled trials to determine the effect of calcium supplementation on BP. A systematic search for randomized trials of calcium supplementation and BP in non-pregnant subjects was performed in Medline from 1966 to June 2003. Seventy-one trials were identified, 40 of which met the criteria for meta-analysis (total of 2492 subjects). Two persons independently extracted data from original publications on changes in calcium intake and BP. In addition, data were collected on subjects' characteristics, that is, age, gender, initial BP and initial calcium intake. A random effects model was used to obtain the effect of calcium supplementation on BP, overall and in predefined population subgroups. Calcium supplementation (mean daily dose: 1200 mg) reduced systolic BP by -1.86 mm Hg (95% confidence interval: -2.91 to -0.81) and diastolic BP by -0.99 mm Hg (-1.61 to -0.37). In people with a relatively low calcium intake (< or =800 mg per day) somewhat larger BP estimates were obtained, that is, -2.63 (-4.03 to -1.24) for systolic BP and -1.30 (-2.13 to -0.47) for diastolic BP. Our study suggests that an adequate intake of calcium should be recommended for the prevention of hypertension. More research on BP in people with calcium-deficient diets is warranted.

Impact of dietary and lifestyle factors on the prevalence of hypertension in Western populations

The impact of dietary and lifestyle factors on the prevalence of hypertension was quantified for Finland, Italy, The Netherlands, UK and USA. For this purpose, we combined data of blood pressure (BP) and risk factors distributions in these five countries with BP estimates from randomized controlled trials of dietary and lifestyle factors to obtain population attributable risk percentages (PAR%) for hypertension. Overweight made a substantial contribution to hypertension (PAR%: 11-17%), as was the case for excessive sodium intake (9-17%), low potassium intake (4-17%), physical inactivity (5-13%), and low intake of fish oil (3-16%). PAR% were smaller for low calcium intake (2-8%), low magnesium intake (4-8%), excessive coffee consumption (1-9%) and excessive alcohol intake (2-3%). We conclude that diet and lifestyle have a major impact on hypertension in Western societies. The relative significance of different risk factors varies among populations, which is important for preventive strategies.

Blood pressure response to changes in sodium and potassium intake: a metaregression analysis of randomised trials

The objective of the study was to assess the blood pressure response to changes in sodium and potassium intake and examine effect modification by age, gender, blood pressure, body weight and habitual sodium and potassium intake. Randomised trials of sodium reduction or potassium supplementation and blood pressure were identified through reference lists of systematic reviews and an additional MEDLINE search (January 1995-March 2001). A total of 40 sodium trials and 27 potassium trials in adults with a minimum duration of 2 weeks were selected for analysis. Data on changes in electrolyte intake and blood pressure during intervention were collected, as well as data on mean age, gender, body weight, initial electrolyte intake and initial blood pressure of the trial populations. Blood pressure effects of changes in electrolyte intake were assessed by weighted metaregression analysis, overall and in strata of trial population characteristics. Analyses were repeated with adjustment for potential confounders. Sodium reduction (median: -77 mmol/24 h) was associated with a change of -2.54 mmHg (95% CI: -3.16, -1.92) in systolic blood pressure and -1.96 mmHg (-2.41, -1.51) in diastolic blood pressure. Corresponding values for increased potassium intake (median: 44 mmol/24 h) were -2.42 mmHg (-3.75, -1.08) and -1.57 mmHg (-2.65, -0.50). Blood pressure response was larger in hypertensives than normotensives, both for sodium (systolic: -5.24 vs -1.26 mmHg, P < 0.001; diastolic: -3.69 vs -1.14 mmHg, P < 0.001) and potassium (systolic: -3.51 vs -0.97 mmHg, P=0.089; diastolic: -2.51 vs -0.34 mmHg, P=0.074). In conclusion, reduced intake of sodium and increased intake of potassium could make an important contribution to the prevention of hypertension, especially in populations with elevated blood pressure.

[Nutrition and health--hypertension]

Hypertension, defined as a blood pressure > or = 140/90 mmHg upon repeated measurement or the use of antihypertensive medication, is present in 14% of Dutch adults. A healthy diet plays an important role in both the prevention and treatment of hypertension. Under controlled conditions, very good results have been obtained with the 'Dietary approaches to stop hypertension' (DASH) combination diet, which has recently been developed in the United States. The DASH combination diet contains large amounts of fruit, vegetables, fish and nuts, low-fat dairy products and reduced levels of total and saturated fat. This dietary pattern yielded blood pressure reductions of 11.4/5.5 mmHg in mildly hypertensive patients. Intervention studies have shown a favourable effect of salt reduction on blood pressure in hypertensive patients, even in the case of mild hypertension. Simultaneous increases in potassium and magnesium intake could have an additional beneficial effect. The use of a low-sodium, high-potassium mineral salt could make a useful contribution to the prevention and treatment of hypertension. In case of hypertension, it is further recommended to reduce the intake of liquorice to less than 50 g per day. These dietary measures, combined with weight loss and physical exercise, may prevent drug treatment in patients with mild hypertension.

Bone mineral density and mortality in elderly men and women: the Rotterdam Study

Recent studies have shown that a low bone mineral density (BMD) is associated with a higher risk of mortality. Most studies have investigated this relationship in women only and presented their risk estimates per standard deviation change in BMD. However, when using this approach, a BMD threshold might be missed when relative risks are presented in the traditional manner. Therefore, in this study our aim was to model the relation between BMD and all-cause mortality. In the Rotterdam Study, follow-up was complete for 5819 men and women aged > or =55 years for whom BMD data were available. During an average follow-up of 5.4 years, 399 men and 317 women died. We calculated BMD Z scores using measurements performed at the femoral neck. Cox proportional hazards regression was used to fit the model. An average BMD, reflected by a Z score = 0, was used as the reference. For women, no significant relationship between BMD and overall mortality was observed. For men, however, a cubic model best fitted the relationship under study, also after adjusting for age and body mass index (BMI). The risk of mortality increased when BMD was below average. Similar results were found when separate curves were made for diabetics and nondiabetics, smokers (ever or never), and tertiles of BMI. Excluding subjects who had suffered hip fractures, or adjusting for the number of drugs used and for lower limb disability, essentially did not change results. This suggests that low BMD is not mainly due to morbidity and impaired mobility in our cohort, which makes this a less likely explanation for the observed relation with mortality. The results of our study suggest that, in men, a nonlinear relationship between BMD and mortality exists, which is independent of comorbidity, whereas, in women, no significant relationship was observed.

Serum carotenoids and atherosclerosis. The Rotterdam Study

High circulating levels of carotenoids have been thought to exhibit a protective function in the development of atherosclerosis. We investigated whether aortic atherosclerosis was associated with lower levels of the major serum carotenoids in alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene, and zeaxanthin-in a subsample of the elderly population of the Rotterdam Study. Aortic atherosclerosis was assessed by presence of calcified plaques of the abdominal aorta. The case-control analysis comprised 108 subjects with aortic atherosclerosis and controls. In an age- and sex-adjusted logistic regression model, serum lycopene was inversely associated with the risk of atherosclerosis. The odds ratio for the highest compared to the lowest quartile of serum lycopene was 0.55 (95% CI 0.25-1.22; p(trend)=0.13). Multivariate adjustment did not appreciably alter these results. Stratification by smoking status indicated that the inverse association between lycopene and aortic calcification was most evident in current and former smokers (OR=0.35; 95% CI 0.13-0.94; p(trend)=0.04). No association with atherosclerosis was observed for quartiles of serum concentrations of alpha-carotene, beta-carotene, lutein, and zeaxanthin. In conclusion, this study provides evidence for a modest inverse association between levels of serum lycopene and presence of atherosclerosis, the association being most pronounced in current and former smokers. Our findings suggest that lycopene may play a protective role in the development of atherosclerosis.

Tea flavonoids may protect against atherosclerosis: the Rotterdam Study

BACKGROUND

Epidemiological studies have indicated a protective role of dietary flavonoids in cardiovascular disease, but evidence is still conflicting. Tea is the major dietary source for flavonoids in Western populations. We studied the association of tea intake with aortic atherosclerosis in a general population.

METHODS

The present analysis formed part of the Rotterdam Study, a prospective study of men and women 55 years and older. Dietary intakes were assessed at baseline by a trained dietician who used a semiquantitative food frequency questionnaire. Calcified plaques in the abdominal aorta were radiographically detected after 2 to 3 years of follow-up. Aortic atherosclerosis was classified as "mild," "moderate," or "severe," according to the length of the calcified area (<1 cm, 1-5 cm, and >5 cm, respectively). The association of tea intake with severity of aortic atherosclerosis was studied in 3454 subjects who were free of cardiovascular disease at baseline. Data were analyzed by logistic regression, adjusting for age, sex, body mass index (calculated as weight in kilograms divided by the square of height in meters), smoking, education, and intake of alcohol, coffee, vitamin antioxidants, total fat, and total energy.

RESULTS

Multivariable analyses showed a significant, inverse association of tea intake with severe aortic atherosclerosis. Odds ratios decreased from 0.54 (95% confidence interval [CI], 0.32-0.92) for drinking 125 to 250 mL (1-2 cups) of tea to 0.31 (CI, 0.16-0.59) for drinking more than 500 mL/d (4 cups per day). The associations were stronger in women than in men. The association of tea intake with mild and moderate atherosclerosis was not statistically significant.

CONCLUSION

This study indicates a protective effect of tea drinking against ischemic heart disease.

Enhanced blood pressure response to mild sodium reduction in subjects with the 235T variant of the angiotensinogen gene

The relationship of high salt intake to elevated blood pressure levels has been demonstrated in most populations by cross-sectional, longitudinal, physiological, and clinical intervention studies. Variation within the angiotensinogen gene has been implicated in the genetic control of blood pressure levels and has been suggested to contribute to increased salt sensitivity. A total of 86 hypertensive men and women who had never been treated and who had participated in a 6-month randomized, placebo-controlled, clinical trial of low-sodium mineral salt (19% reduction in urinary sodium versus 12% increase in placebo group) were genotyped at the angiotensinogen M235T locus to test the hypothesis that the 235T allele is associated with a significant blood pressure response to a sodium reduction intervention whereas the 235M allele is not. After adjustment for gender and baseline blood pressure, persons with the TT and MT genotypes showed significant systolic blood pressure reductions on mineral salt compared with control subjects (P = .02 and P = .001, respectively) but not persons with the MM genotype (P = .10). Net adjusted diastolic blood pressure reductions also showed greater significance for persons with the TT and MT genotypes than for persons with the MM genotype (P = .08, P = .01, and P = .83, respectively). The net adjusted systolic and diastolic blood pressure reduction was -8.6/-3.9 mm Hg for persons with the TT genotype, -9.0/-5.2 mm Hg for the MT genotype, and -5.3/-1.0 mm Hg for the MM genotype. We conclude that the 235T allele of the angiotensinogen gene is associated with greater blood pressure decreases than the 235M allele after a sodium reduction intervention. The angiotensinogen gene accounts for some of the interindividual variation of the blood pressure response to sodium reduction.

Dietary antioxidants and risk of myocardial infarction in the elderly: the Rotterdam Study

BACKGROUND

Epidemiologic studies have shown dietary antioxidants to be inversely correlated with ischemic heart disease.

OBJECTIVE

We investigated whether dietary beta-carotene, vitamin C, and vitamin E were related to the risk of myocardial infarction (MI) in an elderly population.

DESIGN

The study sample consisted of 4802 participants of the Rotterdam Study aged 55-95 y who were free of MI at baseline and for whom dietary data assessed by a semiquantitative food frequency questionnaire were available. During a 4-y follow-up period, 124 subjects had an MI. The association between energy-adjusted beta-carotene, vitamin C, and vitamin E intakes and risk of MI was examined by multivariate logistic regression.

RESULTS

Risk of MI for the highest compared with the lowest tertile of beta-carotene intake was 0.55 (95% CI: 0.34, 0.83; P for trend = 0.013), adjusted for age, sex, body mass index, pack-years, income, education, alcohol intake, energy-adjusted intakes of vitamin C and E, and use of antioxidative vitamin supplements. When beta-carotene intakes from supplements were considered, the inverse relation with risk of MI was slightly more pronounced. Stratification by smoking status indicated that the association was most evident in current and former smokers. No association with risk of MI was observed for dietary vitamin C and vitamin E.

CONCLUSION

The results of this observational study in the elderly population of the Rotterdam Study support the hypothesis that high dietary beta-carotene intakes may protect against cardiovascular disease. We did not observe an association between vitamin C or vitamin E and MI.

Dietary assessment in the elderly: validation of a semiquantitative food frequency questionnaire

OBJECTIVE

The study was conducted to assess the relative validity of a 170-item semiquantitative food frequency questionnaire (SFFQ) adapted for use in the elderly.

DESIGN AND SUBJECTS

The study was carried out in a sample of 80 men and women aged 55-75 y participating in a community based prospective cohort study in Rotterdam, The Netherlands. The two-step dietary assessment comprised a simple self-administered questionnaire (20 min) followed by a structured interview with trained dietitians (20 min) based on the completed questionnaire. Multiple food records (FR) collected over a one year period served as reference method. 24 h urine urea was used as indirect marker for protein intake.

RESULTS

Compared with FR, the SFFQ generally overestimated nutrient intake as reflected by difference in means and the ratio of SFFQ to FR. Energy adjustment reduced the observed overestimation. Pearson's correlation coefficients varied from close to 0.5 to about 0.9 for crude data, and after adjustment for age, sex, total energy intake, and for within-person variability in daily intake for 0.4-0.8. Cross-classification into quintiles resulted in correct classification into the same or adjacent quintile of 75.8% for crude and 76.8% for energy-adjusted data. Validation of protein intake estimated by SFFQ with protein excretion from 24h urine urea indicated overestimation of protein intake by SFFQ. Spearman correlation coefficient between protein intake estimated from urea excretion and SFFQ was 0.67.

CONCLUSIONS

Adaptation of a SFFQ for use in the elderly resulted in a valid and time-efficient dietary assessment instrument. Its ability to adequately rank study subjects according to their dietary intake support its application in epidemiological studies in the elderly.

Electrolytes are associated with blood pressure at old age: the Rotterdam Study

We examined the association of urinary sodium and potassium excretion with blood pressure (BP) in the Rotterdam Study, a population-based study among 7983 men and women aged 55 and over. The present analysis included 1006 subjects with complete BP and urinary data who did not use antihypertensive drugs and did not report themselves to be hypertensive. Electrolyte excretions were assessed in a timed nocturnal urine sample and standardized to 24-h values. The association of electrolyte excretions with BP was studied in a multiple linear regression model with adjustment for age, sex, and body mass index. When sodium and potassium were entered simultaneously into the multivariate model, a 100 mmol increase in potassium was associated with a 9.4 decrease in systolic (P = 0.01) and a 4.9 mm Hg decrease in diastolic BP (P = 0.01). Sodium was directly related to BP, with a 2.2 mm Hg increase in systolic (P = 0.06) and a 0.8 mm Hg increase in diastolic BP (P = 0.14) per 100 mmol. Our findings suggest that an increased intake of potassium and a decrease intake of salt may lower BP at old age.

Long-term effects of neonatal sodium restriction on blood pressure

In 1980, a randomized trial was conducted among 476 Dutch newborn infants to study the effect of a low or normal sodium diet on blood pressure during the first 6 months of life. At the end of the trial, systolic blood pressure in the low sodium group (n = 231) was 2.1 mm Hg lower than in the control group (n = 245). To investigate whether contrasting levels of sodium intake in infancy are associated with blood pressure differences in adolescence, we measured blood pressure in 167 children from the original cohort (35%) after 15 years of follow-up. We assessed the differences in systolic and diastolic blood pressure levels between the diet groups using a multivariate regression model with adjustment for potential confounders. The adjusted systolic blood pressure at follow-up was 3.6 mm Hg lower (95% confidence interval, -6.6 to -0.5) and the diastolic pressure was 2.2 mm Hg lower (95% confidence interval, -4.5 to 0.2) in children who had been assigned to the low sodium group (n = 71) compared with the control group (n = 96). These findings suggest that sodium intake in infancy may be important in relation to blood pressure later in life.

Dietary electrolyte intake and blood pressure in older subjects: the Rotterdam Study

OBJECTIVE

To examine the relation between dietary electrolyte intake and blood pressure in older people.

METHODS

The study included 3239 participants of the Rotterdam Study (41% of the total cohort) who were aged over 55 years and had not been prescribed antihypertensive drugs. Their dietary intake was assessed by a semiquantitative food frequency questionnaire. The association of energy-adjusted intakes of potassium, magnesium and calcium with blood pressure was studied in a linear regression model with adjustment for age, sex, body mass index and alcohol intake.

RESULTS

An increase in potassium intake of 1 g/day was associated with a 0.9 mmHg lower systolic and a 0.8 mmHg lower diastolic blood pressure. An increase in magnesium intake of 100 mg was associated with a 1.2 mmHg lower systolic and a 1.1 mmHg lower diastolic blood pressure. Calcium intake was not independently related to blood pressure, except for a subgroup of 1360 hypertensive subjects in which a significant inverse association with diastolic blood pressure was observed.

CONCLUSIONS

Our findings support the view that an increase in the intake of foods rich in potassium and magnesium could lower blood pressure at older age.

Long-term moderate sodium restriction does not adversely affect the serum HDL/total cholesterol ratio

We examined the effect of long-term moderate sodium restriction on the HDL/total cholesterol ratio within a randomised trial of the effect of mineral salt on blood pressure (BP). Eighty nine untreated hypertensive men and women aged 55-75 years were included in the analysis. During 24 weeks, 46 subjects used a low sodium, high potassium, high magnesium salt and 43 controls used common salt. Serum cholesterol levels were measured at baseline and at the end of the trial. After 24 weeks, 24 h urinary sodium was decreased by 41 mmol (95% Cl 23-60 mmol, P < 0.0001) in the mineral salt group compared with the controls. Serum total cholesterol was decreased in both groups, but 0.45 mmol/l (95% Cl 0.12-0.78, P = 0.01) more in the controls than in the mineral salt group after adjustment for age, sex and changes in body weight, serum total protein and potassium excretion. Serum HDL-cholesterol was decreased by 0.07 mmol/l in the controls and increased by 0.06 mmol/l in the mineral salt group, yielding a difference of 0.14 mmol/l (95% Cl 0.05-0.22 mmol/l, P = 0.003). The change in HDL/total cholesterol ratio was more favourable in the mineral salt group than in the controls (0.014 and 0.004 units, respectively, P = 0.014). We conclude that long-term moderate sodium restriction does not adversely affect the serum HDL/total cholesterol ratio and is a safe dietary measure for lowering BP.

[Risk factors for cardiovascular diseases in the elderly; the ERGO study (Erasmus Rotterdam Health and the Elderly)]

OBJECTIVE

To determine the prevalence of risk factors for cardiovascular disease among elderly people.

DESIGN

Prospective cohort study.

SETTING

A district of Rotterdam, the Netherlands.

METHODS

As a part of the Rotterdam Study information about smoking habits, blood pressure, Quetelet index and serum cholesterol of 7,983 responding persons (78%) (3,105 men and 4,878 women) of 55 years and older was obtained by an interview and physical examination during two visits to a research center.

RESULTS

Among men and women there were 29.7% and 16.7% smokers and 60.1% and 25.9% ex-smokers, respectively. Among men the proportion of smokers decreased from 31.0% in the age category 55-59 years to 15.9% in de category > or = 85 years, among women from 28.0% to 2.7%. Systolic blood pressure increased with age in both sexes, while diastolic blood pressure hardly changed. Hypertension (systolic blood pressure 160 mmHg and/or diastolic blood pressure > or = 95 mmHg at a single measurement and/or use of antihypertensive drugs) occurred in 23.3% of men and 28.0% of women. In men, total serum cholesterol decreased gradually with age, whereas in women there was a slight increase up to the category 70-74 years. No evident change in HDL cholesterol with increasing age was observed in men, but in women a decrease was observed until the same level was reached as in men. Thirty-five per cent of men and 49.5% of women had an elevated level of serum cholesterol (> or = 6.5 mmol/l). The prevalence of obesity (Quetelet index > 25 kg/m2) was about 50% in both men and women but was less in the categories from 75 years onwards. Approximately 80% of men and women had at least one risk factor, while in almost half of them two or more risk factors were found.

CONCLUSION

Risk factors for cardiovascular disease are common among elderly people.

Reduction in blood pressure with a low sodium, high potassium, high magnesium salt in older subjects with mild to moderate hypertension

OBJECTIVE

To examine the effect of a reduced sodium and increased potassium and magnesium intake on blood pressure.

DESIGN

Randomised double blind placebo controlled trial.

SETTING

General population of a suburb of Rotterdam.

SUBJECTS

100 men and women between 55 and 75 years of age with untreated mild to moderate hypertension.

INTERVENTIONS

During 24 weeks the intervention group received a mineral salt (sodium: potassium: magnesium 8:6:1) and foods prepared with the mineral salt. Controls received common salt and foods.

MAIN OUTCOME MEASURE

Change in blood pressure.

RESULTS

Complete follow up was achieved for 97 of the 100 randomised subjects. Systolic blood pressure (mean of measurements at weeks 8, 16, and 24) fell by 7.6 mm Hg (95% confidence interval 4.0 to 11.2) and diastolic blood pressure by 3.3 mm Hg (0.8 to 5.8) in the mineral salt group compared with the controls, with a 28% decrease in urinary sodium excretion and a 22% increase in urinary potassium excretion. Twenty five weeks after the study the difference in blood pressure between the groups was no longer detectable.

CONCLUSION

Replacing common sodium salt by a low sodium, high potassium, high magnesium mineral salt could offer a valuable non-pharmacological approach to lowering blood pressure in older people with mild to moderate hypertension.

Sodium and potassium intake and blood pressure change in childhood

OBJECTIVE

To assess the association between sodium and potassium intake and the rise in blood pressure in childhood.

DESIGN

Longitudinal study of a cohort of children with annual measurements during an average follow up period of seven years.

SETTING

Epidemiological survey of the population of a suburban town in western Netherlands.

SUBJECTS

Cohort of 233 children aged 5-17 drawn at random from participants in the population survey.

MAIN OUTCOME MEASURES

At least six annual timed overnight urine samples were obtained. The mean 24 hour sodium and potassium excretion during the follow up period was estimated for each participant and the sodium to potassium ratio calculated. Individual slopes of blood pressure over time were calculated by linear regression analysis.

RESULTS

No significant association was observed between sodium excretion and the change in blood pressure over time. The mean systolic blood pressure slopes, however, were lower when potassium intake was higher (coefficient of linear regression -0.045 mm Hg/year/mmol; 95% confidence interval -0.069 to -0.020), and the change in systolic pressure was greater when the urinary sodium to potassium ratio was higher (0.356 mm Hg/year/unit; 95% confidence interval 0.069 to 0.642). In relation to potassium this was interpreted as a rise in blood pressure that was on average 1.0 mm Hg (95% confidence interval -1.65 to -0.35) lower in children in the upper part of the distribution of intake compared with those in the lower part. The mean yearly rise in systolic blood pressure for the group as a whole was 1.95 mm Hg. Urinary electrolyte excretion was not associated with diastolic blood pressure.

CONCLUSION

Dietary potassium and the dietary sodium to potassium ratio are related to the rise in blood pressure in childhood and may be important in the early pathogenesis of primary hypertension.