No effect of plasma trimethylamine N-Oxide (TMAO) and plasma trimethyllysine (TML) on the association between choline intake and acute myocardial infarction risk in patients with stable angina pectoris

Plasma concentrations of trimethylamine N-oxide (TMAO) have been linked to cardiovascular disease (CVD) risk and mortality. TMAO is formed through the bacterial conversion of trimethylamine which is obtained either directly from food, generated from dietary precursors (e.g. choline) or derived from endogenous trimethyllysine (TML) production. In a previous article, we reported an increased risk of acute myocardial infarction with increased total choline intake in patients with stable angina pectoris. Due to the close link between TMAO, TML, choline metabolism and possibly CVD, we investigated whether plasma TMAO and TML modified the effect of total choline intake on acute myocardial infarction (AMI) risk in a post-hoc analysis. We found plasma TMAO and TML do not modify the association between higher dietary choline intake and increased AMI risk. Additionally, this association is not mediated via TMAO.publishedVersio

B-vitamin Treatment Modifies the Mortality Risk Associated with Calcium Channel Blockers in Patients with Suspected Stable Angina Pectoris: A Prospective Cohort Study

Background Calcium channel blockers (CCBs) are used for the treatment of cardiovascular disease (CVD), including angina pectoris, and hypertension; however, the effect on survival remains uncertain. CCBs impair fibrinolysis and have been linked to elevated plasma homocysteine (Hcy), a CVD risk marker. Objective We explored the association between CCB use and mortality in a large prospective cohort of patients with suspected stable angina pectoris (SAP), and potential effect modifications by Hcy-lowering B-vitamin treatment (folic acid, B12, and/or B6) as 61.8% of the patients participated in a randomized placebo-controlled B-vitamin intervention trial. Methods Patient baseline continuous characteristics according to CCB treatment were tested by linear regression. Hazard ratios (HRs) for mortality associated with CCB treatment, also according to B-vitamin intervention, were examined using Cox regression analysis. The multivariable model included CVD risk factors, medical histories, and the use of CVD medications. Results A total of 3991 patients (71.5 % men) were included, of whom 907 were prescribed CCBs at discharge. During 10.3 years of median follow-up, 20.6% died and 8.9% from cardiovascular- and 11.7% from non-cardiovascular causes. Patients treated with CCBs had higher plasma Hcy, fibrinogen levels, and erythrocyte sedimentation rate (all P<0.001). Furthermore, CCB use was positively associated with mortality, also after multivariable adjustments (HRs [95% CIs]: 1.34 [1.15,1.57], 1.35 [1.08,1.70], and 1.33 [1.09,1.64] for total, CVD, and non-CVD death, respectively). Numerically stronger associations were observed among patients not treated with B-vitamins (HR [95% CI]: 1.54 [1.25, 1.88], 1.69 [1.25, 2.30], and 1.41 [1.06, 1.86] for total, CVD deaths, and non-CVD deaths, respectively), whereas no association was seen in patients treated with B-vitamins (HR [95% CI]: 1.15 [0.91, 1.46], 1.09 [0.76, 1.57], and 1.20 [0.88, 1.65]). Conclusions In patients with suspected SAP, CCB treatment was associated with increased mortality risk primarily among patients not treated with B-vitamins.publishedVersio

Food Sources Contributing to Intake of Choline and Individual Choline Forms in a Norwegian Cohort of Patients With Stable Angina Pectoris

Choline is an essential nutrient involved in a wide range of physiological functions. It occurs in water- and lipid-soluble forms in the body and diet. Foods with a known high choline content are eggs, beef, chicken, milk, fish, and selected plant foods. An adequate intake has been set in the US and Europe, however, not yet in the Nordic countries. A higher intake of lipid-soluble choline forms has been associated with increased risk of acute myocardial infarction, highlighting the need for knowledge about food sources of the individual choline forms. In general, little is known about the habitual intake and food sources of choline, and individual choline forms.publishedVersio

Primary cardiovascular risk prediction by LDL-cholesterol in Caucasian middle-aged and older adults: a joint analysis of three cohorts

Under embargo until: 2022-06-01Aims Low-density lipoprotein cholesterol (LDL-C) is an established causal driver of atherosclerotic cardiovascular disease (ASCVD), but its performance and age-dependency as a biomarker for incident events and mortality arising from ASCVD is less clear. The aim was to determine the value of LDL-C as a susceptibility/risk biomarker for incident coronary heart disease (CHD), ASCVD, and stroke events and deaths, for the age groups <50 and ≥50 years. Methods and results The performance of LDL-C was evaluated in three cohorts, FINRISK 2002 (n = 7709), HUSK (n = 5431), and ESTHER (n = 4559), by Cox proportional hazards models, C-statistics, and net reclassification index calculations. Additionally, the hazard ratios (HRs) for the three cohorts were pooled by meta-analysis. The most consistent association was observed for CHD [95% confidence interval (CI) for HRs per standard deviation ranging from 0.99 to 1.37], whereas the results were more modest for ASCVD (0.96–1.18) due to lack of association with stroke (0.77–1.24). The association and discriminatory value of LDL-C with all endpoints in FINRISK 2002 and HUSK were attenuated in subjects 50 years and older [HRs (95% CI) obtained from meta-analysis 1.11 (1.04–1.18) for CHD, 1.15 (1.02–1.29) for CHD death, 1.02 (0.98–1.06) for ASCVD, 1.12 (1.02–1.23) for ASCVD death, and 0.97 (0.89–1.05) for stroke]. Conclusion In middle-aged and older adults, associations between LDL-C and all the studied cardiovascular endpoints were relatively weak, while LDL-C showed stronger association with rare events of pre-mature CHD or ASCVD death among middle-aged adults. The predictive performance of LDL-C also depends on the studied cardiovascular endpoint.acceptedVersio

Exploratory analyses on the effect of time since last meal on concentrations of amino acids, lipids, one-carbon metabolites, and vitamins in the Hordaland Health Study

Purpose Dietary intake may have pronounced effects on circulating biomarker concentrations. Therefore, the aim was to provide a descriptive overview of serum metabolite concentrations in relation to time since last meal, focusing on amino acids, lipids, one-carbon metabolites, and biomarkers of vitamin status. Methods We used baseline data from the observational community-based Hordaland Health Study, including 2960 participants aged 46–49 years and 2874 participants aged 70–74 years. A single blood draw was taken from each participant, and time since last meal varied. Estimated marginal geometric mean metabolite concentrations were plotted as a function of time since last meal, up to 7 h, adjusted for age, sex, and BMI. Results We observed a common pattern for nearly all amino acids and one-carbon metabolites with highest concentrations during the first 3 h after dietary intake. Homocysteine and cysteine were lowest the 1st hour after a meal, while no patterns were observed for glutamate and glutamic acid. The concentrations of phylloquinone and triglycerides were highest 1 h after dietary intake. Thiamine and thiamine monophosphate concentrations were highest, while flavin mononucleotide concentrations were lowest within the first 2 h after a meal. No clear patterns emerged for the other fat-soluble vitamins, blood lipids, or B-vitamin biomarkers. Conclusion Our findings suggest that distinguishing between “fasting” and “non-fasting” blood samples may be inadequate, and a more granular approach is warranted. This may have implications for how to account for dietary intake when blood sampling in both clinical and research settings.publishedVersio

Hepatic Energy Metabolism Underlying Differential Lipidomic Responses to High-Carbohydrate and High-Fat Diets in Male Wistar Rats

Background Low-carbohydrate diets are suggested to exert metabolic benefits by reducing circulating triacylglycerol (TG) concentrations, possibly by enhancing mitochondrial activity. Objective We aimed to elucidate mechanisms by which dietary carbohydrate and fat differentially affect hepatic and circulating TG, and how these mechanisms relate to fatty acid composition. Methods Six-week-old, ∼300 g male Wistar rats were fed a high-carbohydrate, low-fat [HC; 61.3% of energy (E%) carbohydrate] or a low-carbohydrate, high-fat (HF; 63.5 E% fat) diet for 4 wk. Parameters of lipid metabolism and mitochondrial function were measured in plasma and liver, with fatty acid composition (GC), high-energy phosphates (HPLC), carnitine metabolites (HPLC-MS/MS), and hepatic gene expression (qPCR) as main outcomes. Results In HC-fed rats, plasma TG was double and hepatic TG 27% of that in HF-fed rats. The proportion of oleic acid (18:1n–9) was 60% higher after HF vs. HC feeding while the proportion of palmitoleic acid (16:1n–7) and vaccenic acid (18:1n–7), and estimated activities of stearoyl-CoA desaturase, SCD-16 (16:1n–7/16:0), and de novo lipogenesis (16:0/18:2n–6) were 1.5–7.5-fold in HC vs. HF-fed rats. Accordingly, hepatic expression of fatty acid synthase (Fasn) and acetyl-CoA carboxylase (Acaca/Acc) was strongly upregulated after HC feeding, accompanied with 8-fold higher FAS activity and doubled ACC activity. There were no differences in expression of liver-specific biomarkers of mitochondrial biogenesis and activity (Cytc, Tfam, Cpt1, Cpt2, Ucp2, Hmgcs2); concentrations of ATP, AMP, and energy charge; plasma carnitine/acylcarnitine metabolites; or peroxisomal fatty acid oxidation. Conclusions In male Wistar rats, dietary carbohydrate was converted into specific fatty acids via hepatic lipogenesis, contributing to higher plasma TG and total fatty acids compared with high-fat feeding. In contrast, the high-fat, low-carbohydrate feeding increased hepatic fatty acid content, without affecting hepatic mitochondrial fatty acid oxidation.publishedVersio

Complement component 7 is associated with total- and cardiac death in chest-pain patients with suspected acute coronary syndrome

Background Complement activation has been associated with atherosclerosis, atherosclerotic plaque destabilization and increased risk of cardiovascular events. Complement component 7 (CC7) binds to the C5bC6 complex which is part of the terminal complement complex (TCC/C5b-9). High-sensitivity C-reactive protein (hsCRP) is a sensitive marker of systemic inflammation and may reflect the increased inflammatory state associated with cardiovascular disease. Aim To evaluate the associations between CC7 and total- and cardiac mortality in patients hospitalized with chest-pain of suspected coronary origin, and whether combining CC7 with hsCRP adds prognostic information. Methods Baseline levels of CC7 were related to 60-months survival in a prospective, observational study of 982 patients hospitalized with a suspected acute coronary syndrome (ACS) at 9 hospitals in Salta, Argentina. A cox regression model, adjusting for conventional cardiovascular risk factors, was fitted with all-cause mortality, cardiac death and sudden cardiac death (SCD) as the dependent variables. A similar Norwegian population of 871 patients was applied to test the reproducibility of results in relation to total death. Results At follow-up, 173 patients (17.7%) in the Argentinean cohort had died, of these 92 (9.4%) were classified as cardiac death and 59 (6.0%) as SCD. In the Norwegian population, a total of 254 patients (30%) died. In multivariable analysis, CC7 was significantly associated with 60-months all-cause mortality [hazard ratio (HR) 1.26 (95% confidence interval (CI), 1.07–1.47) and cardiac death [HR 1.28 (95% CI 1.02–1.60)], but not with SCD. CC7 was only weakly correlated with hsCRP (r = 0.10, p = 0.002), and there was no statistically significant interaction between the two biomarkers in relation to outcome. The significant association of CC7 with total death was reproduced in the Norwegian population. Conclusions CC7 was significantly associated with all-cause mortality and cardiac death at 60-months follow-up in chest-pain patients with suspected ACS.publishedVersio

Even chained acylcarnitines predict long-term cardiovascular prognosis in patients with chest pain and non-obstructive coronary artery disease

Background Acylcarnitines are essential for mitochondrial fatty acid oxidation. Earlier studies suggest that impaired energy metabolism may be implicated in the pathogenesis of microvascular angina. We explored metabolites from the carnitine pathway as predictors of cardiovascular disease (CVD) - and all-cause mortality among patients with non-obstructive coronary artery disease (NOCAD). Methods A total of 1046 patients with suspected stable coronary syndrome underwent coronary angiography during 2000–2004, with findings of NOCAD. Serum levels of 8 selected carnitine metabolites were analyzed through liquid chromatography tandem mass spectrometry. Associations with CVD- and all-cause mortality were assessed by multivariable Cox regression models. Results Median age at inclusion was 57 years. 51.5% were men. During median (25th- 75th percentiles), 14.1 (13.2–15.4) years of follow-up, 5.7% of the participants died from CVD and the incidence of all-cause mortality was 17.3%. Serum acetyl, octanoyl- and palmitoylcarnitine predicted CVD mortality with multivariable HR and 95% CI (per SD increment log transformed) of 1.36 (1.01–1.83), 1.49 (1.15–1.93) and 2.07 (1.49–2.85), p ≤ 0.04, respectively. Higher serum acetyl- and palmitoylcarnitines were also associated with increased risk of all-cause mortality (HR (95% CI): 1.27 (1.01–1.50), and 1.51 (1.26–1.81), p ≤ 0.007. Baseline levels of the precursors trimethyllysine and ƴ-butyrobetaine, carnitine or the odd chained propionylcarnitine and (iso)valerylcarnitine were not associated with adverse outcomes. Conclusion Elevated serum even-chained acylcarnitines predicted adverse long-term prognosis in NOCAD. The strongest risk estimates were observed for palmitoylcarnitine, which predicted both CVD- and all-cause mortality after extensive multivariable adjustments. Underlying pathomechanisms should be further elucidated.publishedVersio

Changes in lipoprotein particle subclasses, standard lipids, and apolipoproteins after supplementation with n-3 or n-6 PUFAs in abdominal obesity: A randomized double-blind crossover study

Background & aims Marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower circulating levels of triacylglycerols (TAGs), and the plant-derived omega-6 (n-6) PUFA linoleic acid (LA) may reduce cholesterol levels. Clinical studies on effects of these dietary or supplemental PUFAs on other blood fat fractions are few and have shown conflicting results. This study aimed to determine effects of high-dose supplemental n-3 (EPA + DHA) and n-6 (LA) PUFAs from high-quality oils on circulating lipoprotein subfractions and standard lipids (primary outcomes), as well as apolipoproteins, fatty acids, and glycemic control (secondary outcomes), in females and males with abdominal obesity. Methods This was a randomized double-blind crossover study with two 7-wk intervention periods separated by a 9-wk washout phase. Females (n = 16) were supplemented with 3 g/d of EPA + DHA (TAG fish oil) or 15 g/d of LA (safflower oil), while males (n = 23) received a dose of 4 g/d of EPA + DHA or 20 g/d of LA. In fasting blood samples, we investigated lipoprotein particle subclasses by nuclear magnetic resonance spectroscopy, as well as standard lipids, apolipoproteins, fatty acid profiles, and glucose and insulin. Data were analyzed by linear mixed-effects modeling with ‘subjects’ as the random factor. Results The difference between interventions in relative change scores was among the lipoprotein subfractions significant for total very-low-density lipoproteins (VLDLs) (n-3 vs. n-6: −38%∗ vs. +16%, p < 0.001; ∗: significant within-treatment change score), large VLDLs (−58%∗ vs. −0.91%, p < 0.001), small VLDLs (−57%∗ vs. +41%∗, p < 0.001), total low-density lipoproteins (LDLs) (+5.8%∗ vs. −4.3%∗, p = 0.002), large LDLs (+23%∗ vs. −2.1%, p = 0.004), total high-density lipoproteins (HDLs) (−6.0%∗ vs. +3.7%, p < 0.001), large HDLs (+11%∗ vs. −5.3%, p = 0.001), medium HDLs (−24%∗ vs. +6.2%, p = 0.030), and small HDLs (−9.9%∗ vs. +9.6%∗, p = 0.002), and among standard lipids for TAGs (−16%∗ vs. −2.6%, p = 0.014), non-esterified fatty acids (−19%∗ vs. +5.5%, p = 0.033), and total cholesterol (−0.28% vs. −4.4%∗, p = 0.042). A differential response in relative change scores was also found for apolipoprotein (apo)B (+0.40% vs. −6.0%∗, p = 0.008), apoA-II (−6.0%∗ vs. +1.5%, p = 0.001), apoC-II (−11%∗ vs. −1.7%, p = 0.025), and apoE (+3.3% vs. −3.8%, p = 0.028). Conclusions High-dose supplementation of high-quality oils with n-3 (EPA + DHA) or n-6 (LA) PUFAs was followed by reductions in primarily TAG- or cholesterol-related markers, respectively. The responses after both interventions point to changes in the lipoprotein–lipid–apolipoprotein profile that have been associated with reduced cardiometabolic risk, also among people with TAG or LDL-C levels within the normal range.publishedVersio

Trimethyllysine predicts all-cause and cardiovascular mortality in community-dwelling adults and patients with coronary heart disease

Aims Trimethyllysine (TML) is involved in carnitine synthesis, serves as a precursor of trimethylamine N-oxide (TMAO) and is associated with cardiovascular events in patients with established coronary heart disease (CHD). We prospectively examined circulating TML as a predictor of all-cause and cardiovascular mortality in community-dwelling adults and patients with CHD. Methods and results By Cox regression modelling, risk associations were examined in 6393 subjects in the community-based Hordaland Health Study (HUSK). A replication study was conducted among 4117 patients with suspected stable angina pectoris in the Western Norway Coronary Angiography Cohort (WECAC). During a mean follow-up of 10.5 years in the HUSK-cohort, 884 (13.8%) subjects died, of whom 287 from cardiovascular causes. After multivariable adjustments for traditional cardiovascular risk factors, the hazard ratio (HR) [95% confidence interval (95% CI)] for all-cause mortality comparing the 4th vs. 1st TML-quartile was 1.66 (1.31–2.10, P < 0.001). Particularly strong associations were observed for cardiovascular mortality [HR (95% CI) 2.04 (1.32–3.15, P = 0.001)]. Corresponding risk-estimates in the WECAC (mean follow-up of 9.8 years) were 1.35 [1.10–1.66, P = 0.004] for all-cause and 1.45 [1.06–1.98, P = 0.02] for cardiovascular mortality. Significant correlations between plasma TML and TMAO were observed in both cohorts (rs ≥ 0.42, P < 0.001); however, additional adjustments for TMAO did not materially influence the risk associations, and no effect modification by TMAO was found. Conclusions Elevated TML-levels were associated with increased risk of all-cause and cardiovascular mortality both in subjects with and without established CHD.publishedVersio