Circulating ketone bodies and cardiovascular outcomes: the MESA study

Integrative analysis of genes provides insights into the molecular and immune characteristics of mitochondria-related genes in atherosclerosis

Atherosclerosis is a chronic inflammatory disease characterized by lipid accumulation in arterial walls. The role of the interplay between mitochondrial dysfunction and immune inflammation in atherosclerosis is still unclear. This study aimed to investigate the molecular characteristics and immune landscape of mitochondrial hub genes involved in atherosclerosis. Based on bioinformatics analysis, three hub Mitochondria-related DEGs (MitoDEGs), including OXCT1, UCP2, and CPT1B, were screened out and showed good diagnostic performance in identifying atherosclerosis patients and controls. Immune analysis demonstrated strong correlations between hub MitoDEGs and immune cells, such as macrophages and T cells. Additionally, the predicted transcription factors of these hub MitoDEGs were significantly enriched in Th17, Th1 and Th2 cell differentiation signaling pathways. Both cell and animal experiments confirmed the expression trends of OXCT1 and CPT1B observed in the bioinformatics analysis. These hub MitoDEGs may play an important role in coordinating mitochondrial metabolism in the immune inflammation of atherosclerosis.

Circulating β-hydroxybutyrate levels are associated with major adverse clinical events in patients with acute myocardial infarction

BACKGROUND AND AIMS

Acute myocardial infarction is associated with high mortality, and effective biomarkers are required for the risk stratification. In cardiovascular diseases, circulating levels of ketone bodies (KB) such as β-hydroxybutyrate (β-OHB) and acetoacetate are altered. However, the relationship between circulating KB levels and major adverse clinical events (MACE) in patients with ST-elevation myocardial infarction (STEMI) is unknown.

METHODS AND RESULTS

Patients with STEMI undergoing percutaneous coronary intervention (PCI) between January 2010 to June 2020 were enrolled, and divided into T1 (<0.09 mmol/L, n = 219), T2 (0.09-0.28 mmol/L, n = 202), and T3 (>0.28 mmol/L, n = 211) tertiles according to the circulating β-OHB levels within 24 h of admission. The primary endpoint was in-hospital MACE. The incidence of in-hospital MACE in the T3 group (20.9 %) was significantly higher than in the T1 group (10.5 %) and T2 group (14.9 %) (P = 0.012). Multivariate logistic regression analysis showed that elevated circulating β-OHB levels were associated with an increased risk of all-cause mortality and MACE during hospitalization (OR = 1.38, 95 % CI = 1.08-1.77, P = 0.009). During follow-up period, multivariate Cox regression analyses showed that elevated circulating β-OHB levels were associated with higher all-cause mortality and MACE (HR = 1.35, 95 % CI = 1.17-1.56, P < 0.001). The impact of β-OHB on MACE were similar for all the subgroups.

CONCLUSION

Elevated circulating β-OHB levels within 24 h of admission were associated with an increased risk of MACE in patients with STEMI undergoing PCI, and could be a promising prognosis biomarker.

A Novel Metabolomic Aging Clock Predicting Health Outcomes and Its Genetic and Modifiable Factors

Existing metabolomic clocks exhibit deficiencies in capturing the heterogeneous aging rates among individuals with the same chronological age. Yet, the modifiable and non-modifiable factors in metabolomic aging have not been systematically studied. Here, a new aging measure-MetaboAgeMort-is developed using metabolomic profiles from 239,291 UK Biobank participants for 10-year all-cause mortality prediction. The MetaboAgeMort showed significant associations with all-cause mortality, cause-specific mortality, and diverse incident diseases. Adding MetaboAgeMort to a conventional risk factors model improved the predictive ability of 10-year mortality. A total of 99 modifiable factors across seven categories are identified for MetaboAgeMort. Among these, 16 factors representing pulmonary function, body composition, socioeconomic status, dietary quality, smoking status, alcohol intake, and disease status showed quantitatively stronger associations. The genetic analyses revealed 99 genomic risk loci and 271 genes associated with MetaboAgeMort. The tissue-enrichment analysis showed significant enrichment in liver. While the external validation of the MetaboAgeMort is required, this study illuminates heterogeneous metabolomic aging across the same age, providing avenues for identifying high-risk individuals, developing anti-aging therapies, and personalizing interventions, thus promoting healthy aging and longevity.

Circulating ketone bodies, genetic susceptibility, with left atrial remodeling and atrial fibrillation: A prospective study from the UK Biobank

BACKGROUND

Ketone bodies (KBs) are an important cardiac metabolic energy source. Metabolic remodeling has recently been found to play an important role in the pathological process of atrial fibrillation (AF).

OBJECTIVE

The purpose of this study was to evaluate the associations of circulating KB levels with incident AF risk in the general population.

METHODS

We studied 237,163 participants [mean age, 56.5 years; 129,472 women (55%)] from the UK Biobank who were free of AF at baseline and had data on circulating β-hydroxybutyrate (β-OHB), acetoacetate, and acetone. The associations of KBs with new-onset AF were evaluated using Cox regression in the general population and across the 3 genetic risk groups: low, moderate, and high polygenic risk score of AF.

RESULTS

During a median follow-up of 14.8 (13.8, 15.5) years, 16,638 participants (7.0%) developed AF. There was a U-shaped association of total KBs and β-OHB with incident AF, with nadirs at 60.6 and 40.8 μmol/L, respectively (Pnonlinear < .05), whereas there was a positive association of acetoacetate and acetone with AF (Poverall < .001; Pnonlinear > .05). Consistently, there was a U-shaped association of total KBs and β-OHB with left atrial (LA) volume parameters, including LA maximum volume, LA minimum volume, and their body surface area-indexed counterparts, and there was an inverted U-shaped association of total KBs and β-OHB with LA ejection fraction (Pnonlinear < .05 for all). The associations of KBs with AF were stronger in individuals with low genetic risk (Pinteraction < .05), while the highest AF risk was in those with high genetic risk with high KB levels. Significant mediation effects of inflammatory markers on the associations between KBs and AF were identified.

CONCLUSION

There was a U-shaped association of circulating total KBs and β-OHB with incident AF as well as a positive association of acetoacetate and acetone levels with AF risk in the general population.

Association patterns of ketone bodies with the risk of adverse outcomes according to diabetes status

AIM

To investigate the associations between ketone bodies (KB) and multiple adverse outcomes including cardiovascular disease (CVD), chronic kidney disease (CKD) and all-cause mortality according to diabetes status.

METHODS

This prospective study included 222 824 participants free from CVD and CKD at baseline from the UK Biobank. Total KB including β-hydroxybutyrate, acetoacetate and acetone were measured by nuclear magnetic resonance. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between KB and adverse outcomes among participants with normoglycaemia, prediabetes and type 2 diabetes, respectively.

RESULTS

During a mean follow-up of 14.1 years, 24 088 incident CVD events (including 17 303 coronary heart disease events, 5172 stroke events and 5881 heart failure [HF] events), 8605 CKD events and 15 813 deaths, were documented. Higher total KB significantly increased the risk of HF among participants with normoglycaemia (HR, 1.32 [95% CI, 1.17-1.49], per 10-fold increase in total KB) and prediabetes (1.35 [1.04-1.76]), and increased the risk of CKD among those with normoglycaemia (1.20 [1.09-1.33]). Elevated KB levels were associated with an increased risk of all-cause mortality across the glycaemic spectrum (1.32 [1.23-1.42] for normoglycaemia, 1.45 [1.24-1.71] for prediabetes and 1.47 [1.11-1.94] for diabetes). Moreover, a significant additive interaction between KB and diabetes status was observed on the risk of death (P = .009), with 4.9% of deaths attributed to the interactive effects.

CONCLUSIONS

Our study underscored the variation in association patterns between KB and adverse outcomes according to diabetes status and suggested that KB could interact with diabetes status in an additive manner to increase the risk of mortality.

The ketogenic diet does not improve cardiac function and blunts glucose oxidation in ischaemic heart failure

AIMS

Cardiac energy metabolism is perturbed in ischaemic heart failure and is characterized by a shift from mitochondrial oxidative metabolism to glycolysis. Notably, the failing heart relies more on ketones for energy than a healthy heart, an adaptive mechanism that improves the energy-starved status of the failing heart. However, whether this can be implemented therapeutically remains unknown. Therefore, our aim was to determine if increasing ketone delivery to the heart via a ketogenic diet can improve the outcomes of heart failure.

METHODS AND RESULTS

C57BL/6J male mice underwent either a sham surgery or permanent left anterior descending coronary artery ligation surgery to induce heart failure. After 2 weeks, mice were then treated with either a control diet or a ketogenic diet for 3 weeks. Transthoracic echocardiography was then carried out to assess in vivo cardiac function and structure. Finally, isolated working hearts from these mice were perfused with appropriately 3H or 14C labelled glucose (5 mM), palmitate (0.8 mM), and β-hydroxybutyrate (β-OHB) (0.6 mM) to assess mitochondrial oxidative metabolism and glycolysis. Mice with heart failure exhibited a 56% drop in ejection fraction, which was not improved with a ketogenic diet feeding. Interestingly, mice fed a ketogenic diet had marked decreases in cardiac glucose oxidation rates. Despite increasing blood ketone levels, cardiac ketone oxidation rates did not increase, probably due to a decreased expression of key ketone oxidation enzymes. Furthermore, in mice on the ketogenic diet, no increase in overall cardiac energy production was observed, and instead, there was a shift to an increased reliance on fatty acid oxidation as a source of cardiac energy production. This resulted in a decrease in cardiac efficiency in heart failure mice fed a ketogenic diet.

CONCLUSION

We conclude that the ketogenic diet does not improve heart function in failing hearts, due to ketogenic diet-induced excessive fatty acid oxidation in the ischaemic heart and a decrease in insulin-stimulated glucose oxidation.

Circulating beta-hydroxybutyrate levels in advanced heart failure with reduced ejection fraction: Determinants and prognostic impact

AIMS

Patients with heart failure (HF) display metabolic alterations, including heightened ketogenesis, resulting in increased beta-hydroxybutyrate (β-OHB) formation. We aimed to investigate the determinants and prognostic impact of circulating β-OHB levels in patients with advanced HF and reduced ejection fraction (HFrEF).

METHODS AND RESULTS

A total of 867 patients with advanced HFrEF (age 57 ± 11 years, 83% male, 45% diabetic, 60% New York Heart Association class III), underwent clinical and echocardiographic examination, circulating metabolite assessment, and right heart catheterization (n = 383). The median β-OHB level was 64 (interquartile range [IQR] 33-161) μmol/L (normal 0-74 μmol/L). β-OHB levels correlated with increased markers of lipolysis (free fatty acids [FFA]), higher natriuretic peptides, worse pulmonary haemodynamics, and lower humoral regulators of ketogenesis (insulin/glucagon ratio). During a median follow-up of 1126 (IQR 410-1781) days, there were 512 composite events, including 324 deaths, 81 left ventricular assist device implantations and 107 urgent cardiac transplantations. In univariable Cox regression, increased β-OHB levels (T3 vs. T1: hazard ratio [HR] 1.39, 95% confidence interval [CI] 1.13-1.72, p = 0.002) and elevated FFA levels (T3 vs. T1: HR 1.39, 95% CI 1.09-1.79, p = 0.008) were both predictors of a worse prognosis. In multivariable Cox analysis evaluating the simultaneous associations of FFA and β-OHB levels with outcomes, only FFA levels remained significantly associated with adverse outcomes.

CONCLUSIONS

In patients with advanced HFrEF, increased plasma β-OHB correlate with FFA levels, worse right ventricular function, greater neurohormonal activation and other markers of HF severity. The association between plasma β-OHB and adverse outcomes is eliminated after accounting for FFA levels, suggesting that increased β-OHB is a consequence reflecting heightened lipolytic state, rather than a cause of worsening HF.

Towards Metabolomic-Based Precision Approaches for Classifying and Treating Heart Failure

Both heart failure and cardiometabolic disease are on the rise, and abnormal cardiac and peripheral metabolism are central to the syndrome of heart failure. Advances in metabolomic profiling have improved our understanding of the heart's metabolic flexibility in patients with and without heart failure. Prior studies have noted patients with heart failure display metabolomic profiles associated with marked abnormalities in the metabolism of fatty acids, branched-chain amino acids, ketones, and glucose compared with control subjects. Metabolomics can highlight specific pathways that are dysregulated; however, other metabolites beyond those related to fuel metabolism may also play a role in precision-medicine approaches. Novel approaches include metabolic flux studies, spatial and single-cell analysis, serial monitoring of treatment response, and integration with other -omics data. The goal of these innovative approaches should be to harness metabolomic technologies to affect precision care for patients with heart failure.

Sex differences in circulating metabolites across glycemic status and risk of coronary heart disease

Background

Women with type 2 diabetes (T2D) have a 50% excess risk of coronary heart disease (CHD) than men with T2D. We compared circulating metabolites and their associations with CHD in men and women across glycemic status.

Methods

We used metabolomic data (lipoproteins, fatty acids, amino acids, glycolysis, ketones, inflammation, and fluid balance) for 87,326 CHD-free UK Biobank participants. We used linear regressions to examine the association of sex and metabolites (log) in newly diagnosed T2D (diagnosis<2 yrs from baseline), prediabetes (A1c 5.7-6.5%), and euglycemia, accounting for age, race, Deprivation Index, income, smoking, alcohol drinking, obesity, physical activity, medications for hypertension, hyperlipidemia, and diabetes. We used Cox models to evaluate the association of metabolites and CHD risk by sex, adjusting the same covariates and menopausal status (women). All analyses were FDR-adjusted.

Findings

We included 1250 individuals with new T2D, 12,706 with prediabetes, and 83,315 with euglycemia. In adjusted linear regressions, women showed a progressive increase in atherogenic lipid and lipoprotein markers and inflammatory marker, glycoprotein acetyls, compared to men as their glycemic status advanced. However, women had lower levels of albumin during this transition. Menopausal status did not alter these sex differences. In a 10-year follow-up, an SD higher total TG, TG in VLDL, LDL, and HDL, saturated fatty acids (SFA) were positively associated with a higher risk of CHD in women with T2D but not in men (p-interactions 0.03-0.15).

Interpretation

With advancing glycemic status, women exhibited higher levels of atherogenic lipids and lipoproteins, as well as inflammatory markers, but lower circulating albumin. Women with T2D appear to be at a higher risk of CHD associated with TG, VLDL-TG, LDL-TG, and HDL-TG, and SFA than men with T2D.

Co-morbid intersections of cancer and cardiovascular disease and targets for natural drug action: Reprogramming of lipid metabolism

Cancer and cardiovascular diseases are major contributors to global morbidity and mortality, and their seemingly separate pathologies are intricately intertwined. In the context of cancer, the cardiovascular disease encompasses not only the side effects arising from anti-tumor treatments but also the metabolic shifts induced by oncological conditions. A growing body of research indicates that lipid metabolic reprogramming serves as a distinctive hallmark of tumors. Furthermore, anomalies in lipid metabolism play a significant role in the development of cardiovascular disease. This study delves into the cardiac implications of lipid metabolic reprogramming within the cancer context, closely examining abnormalities in lipid metabolism present in tumors, cardiac tissue, and immune cells within the microenvironment. Additionally, we examined risk factors such as obesity and anti-tumor therapy. Despite progress, a gap remains in the availability of drugs targeting lipid metabolism modulation for treating tumors and mitigating cardiac risk, with limited advancement seen in prior studies. Here, we present a review of previous research on natural drugs that exhibit both shared and distinct therapeutic effects on tumors and cardiac health by modulating lipid metabolism. Our aim is to provide insights for potential drug development.

A National Study Exploring the Association between Fasting Duration and Mortality among the Elderly

(1) Background: The benefits of weight management are widely recognized, and prolonged fasting duration has become a common method for weight control. The suitability of time-restricted eating (TRE) for elderly individuals remains controversial. This study aims to examine the correlation between fasting duration and mortality within a nationally representative cohort of elderly individuals in the United States. (2) Methods: Data were extracted from a prospective cohort study conducted as part of the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Participants aged over 60 with complete data on dietary intake and mortality follow-up information were included. Fasting duration was assessed using two 24 h dietary recalls. All the participants were categorized into fasting duration quartiles. Mortality outcomes were ascertained through the National Death Index. Cox proportional hazards regression models were utilized to analyze the association between fasting duration and mortality. (3) Results: The final analysis included 10,561 elderly participants (mean age 69.89, 45.58% male). Individuals with the longest fasting duration (over 12.38 h) had a significantly higher risk of CVD mortality compared to those with a normal fasting duration (10.58-12.38 h). This elevated CVD mortality risk was particularly pronounced in males, individuals over 70 years old, and non-shift workers. A non-linear relationship was observed between fasting duration and all-cause mortality and CVD mortality. (4) Conclusions: Prolonged fasting periods are associated with a higher risk of CVD mortality in the elderly population, although this correlation is not evident for all-cause, cancer, or other-cause mortality. A fasting duration of 11.49 h correlates with the lowest mortality risk. Additionally, elderly individuals with the shortest fasting duration exhibit elevated hazard ratios for both cancer and other-cause mortality. As with any health intervention, clinicians should exercise caution when recommending a fasting regimen that is personalized to the health condition of people who are older. Further research through randomized controlled trials should be conducted to comprehensively investigate the impact of TRE on mortality.

Association of a Low-Carbohydrate High-Fat Diet With Plasma Lipid Levels and Cardiovascular Risk

Background

Low-carbohydrate high-fat (LCHF) diets have attracted interest for a variety of conditions. In some individuals, these diets trigger hypercholesterolemia. There are limited data on their effects on cardiovascular disease risk.

Objectives

The purpose of this study was to investigate the association between LCHF dietary patterns, lipid levels, and incident major adverse cardiovascular events (MACE).

Methods

In a cohort from the UK Biobank, participants with ≥1 24-hour dietary questionnaire were identified. A LCHF diet was defined as <100 g/day and/or <25% total daily energy from carbohydrates/day and >45% total daily energy from fat, with participants on a standard diet (SD) not meeting these criteria. Each LCHF case was age- and sex-matched 1:4 to SD individuals.

Results

Of the 2034 LCHF and 8136 SD identified participants, 305 LCHF and 1220 SD individuals completed an enrollment assessment concurrently with lipid collection. In this cohort, low-density lipoprotein-cholesterol (LDL-C) and apolipoprotein B levels were significantly increased in the LCHF vs SD group (P < 0.001). 11.1% of LCHF and 6.2% of SD individuals demonstrated severe hypercholesterolemia (LDL-C >5 mmol/L, P < 0.001). After 11.8 years, 9.8% of LCHF vs 4.3% of SD participants experienced a MACE (P < 0.001). This difference remained significant after adjustment for cardiovascular risk factors (HR: 2.18, 95% CI: 1.39-3.43, P < 0.001). Individuals with an elevated LDL-C polygenic risk score had the highest concentrations of LDL-C on a LCHF diet. Similar significant changes in lipid levels and MACE associations were confirmed in the entire cohort and in ≥2 dietary surveys.

Conclusions

Consumption of a LCHF diet was associated with increased LDL-C and apolipoprotein B levels, and an increased risk of incident MACE.

Emerging Pathophysiological Roles of Ketone Bodies

The discovery of insulin approximately a century ago greatly improved the management of diabetes, including many of its life-threatening acute complications like ketoacidosis. This breakthrough saved many lives and extended the healthy lifespan of many patients with diabetes. However, there is still a negative perception of ketone bodies stemming from ketoacidosis. Originally, ketone bodies were thought of as a vital source of energy during fasting and exercise. Furthermore, in recent years, research on calorie restriction and its potential impact on extending healthy lifespans, as well as studies on ketone bodies, have gradually led to a reevaluation of the significance of ketone bodies in promoting longevity. Thus, in this review, we discuss the emerging and hidden roles of ketone bodies in various organs, including the heart, kidneys, skeletal muscles, and brain, as well as their potential impact on malignancies and lifespan.

Association of ketone bodies with incident CKD and death: A UK Biobank study

AIMS

Although cellular and animal models have suggested a protective effect of ketone bodies (KBs), clinical data are still lacking to support these findings. This study aimed to investigate the association of KB levels with incident chronic kidney disease (CKD) and death.

METHODS

This was a prospective cohort study of 87,899 UK Biobank participants without baseline CKD who had plasma levels of β-hydroxybutyrate, acetoacetate, and acetone levels measured at the time of enrollment. The main predictor was plasma total KB, which was the sum of the aforementioned three KBs. The primary outcome was a composite of incident CKD, or all-cause mortality. Secondary outcomes included the individual components of the primary outcome.

RESULTS

During a median follow-up of 11.9 years, a total of 8,145 primary outcome events occurred (incidence rate 8.0/1,000 person-years). In the multivariable Cox model, a 1-standard deviation increase in log total KB was associated with a 7 % [adjusted hazard ratio (aHR), 1.07; 95 % confidence interval (CI), 1.05-1.10] higher risk of the primary outcome. When stratified into quartiles, the aHR (95 % CI) for Q4 versus Q1 was 1.18 (1.11-1.27). This association was consistent for incident CKD (aHR, 1.04; 95 % CI, 1.01-1.07), and all-cause mortality (aHR, 1.10; 95 % CI, 1.07-1.13). Compared with Q1, Q4 was associated with a 12 % (aHR 1.12; 95 % CI 1.02-1.24) and 26 % (aHR 1.26; 95 % CI 1.15-1.37) higher risk of incident CKD and all-cause mortality, respectively.

CONCLUSIONS

Higher KB levels were independently associated with higher risk of incident CKD and death.

Offspring of women with hyperemesis gravidarum are more likely to have cardiovascular abnormalities

BACKGROUND

Hyperemesis gravidarum (HG) is a severe form of pregnancy-related nausea and vomiting affecting 0.3-2.3% of pregnancies, which can lead to fluid, electrolyte, and acid-base imbalances, nutritional deficiencies, and weight loss, and is usually severe enough to require hospitalization. Abnormally elevated urinary ketones are commonly seen in patients with HG, and ketone bodies are free to pass through the placenta, and maternal hyperketonemia, with or without acidosis, is associated with an increased rate of stillbirth, an increased incidence of congenital anomalies, and impaired neurophysiologic development of the infant. This study investigates the obstetric outcomes of patients with HG and whether HG increases the incidence of cardiovascular disease in the offspring.

METHODS

This study included 1020 pregnant women who were hospitalized in our hospital for HG and ultimately delivered in our hospital as well as pregnant women without HG in early gestation and delivered in our hospital from January 2019-January 2020, and we collected and followed up the clinical information of the pregnant women and their offspring.

RESULTS

Pregnant women with HG were more likely to have severe urinary ketones, the rate of early miscarriage and mid-term miscarriage was significantly higher in women with HG compared to pregnant women without HG. Fetal and neonatal head and abdominal circumferences were smaller in HG group than in control group. Neonatal birth weight and length were also lower in the HG group and cardiovascular anomalies were more likely to occur in the offspring of women with HG when all births were followed up for 3 years.

CONCLUSIONS

HG may cause poor obstetric outcomes and was associated with the development of cardiovascular disease in the offspring of women with HG.

Circulating ketone bodies and mortality in heart failure: a community cohort study

Background

The relationship between ketone bodies (KB) and mortality in patients with heart failure (HF) syndrome has not been well established.

Objectives

The aim of this study is to assess the distribution of KB in HF, identify clinical correlates, and examine the associations between plasma KB and all-cause mortality in a population-based HF cohort.

Methods

The plasma KB levels were measured by nuclear magnetic resonance spectroscopy. Multivariable linear regression was used to examine associations between clinical correlates and KB levels. Proportional hazard regression was employed to examine associations between KB (represented as both continuous and categorical variables) and mortality, with adjustment for several clinical covariates.

Results

Among the 1,382 HF patients with KB measurements, the median (IQR) age was 78 (68, 84) and 52% were men. The median (IQR) KB was found to be 180 (134, 308) μM. Higher KB levels were associated with advanced HF (NYHA class III-IV) and higher NT-proBNP levels (both P < 0.001). The median follow-up was 13.9 years, and the 5-year mortality rate was 51.8% [95% confidence interval (CI): 49.1%-54.4%]. The risk of death increased when KB levels were higher (HRhigh vs. low group 1.23; 95% CI: 1.05-1.44), independently of a validated clinical risk score. The association between higher KB and mortality differed by ejection fraction (EF) and was noticeably stronger among patients with preserved EF.

Conclusions

Most patients with HF exhibited KB levels that were consistent with those found in healthy adults. Elevated levels of KB were observed in patients with advanced HF. Higher KB levels were found to be associated with an increased risk of death, particularly in patients with preserved EF.

Novel Prediction Equations for Absolute Risk Assessment of Total Cardiovascular Disease Incorporating Cardiovascular-Kidney-Metabolic Health: A Scientific Statement From the American Heart Association

Cardiovascular-kidney-metabolic (CKM) syndrome is a novel construct recently defined by the American Heart Association in response to the high prevalence of metabolic and kidney disease. Epidemiological data demonstrate higher absolute risk of both atherosclerotic cardiovascular disease (CVD) and heart failure as an individual progresses from CKM stage 0 to stage 3, but optimal strategies for risk assessment need to be refined. Absolute risk assessment with the goal to match type and intensity of interventions with predicted risk and expected treatment benefit remains the cornerstone of primary prevention. Given the growing number of therapies in our armamentarium that simultaneously address all 3 CKM axes, novel risk prediction equations are needed that incorporate predictors and outcomes relevant to the CKM context. This should also include social determinants of health, which are key upstream drivers of CVD, to more equitably estimate and address risk. This scientific statement summarizes the background, rationale, and clinical implications for the newly developed sex-specific, race-free risk equations: PREVENT (AHA Predicting Risk of CVD Events). The PREVENT equations enable 10- and 30-year risk estimates for total CVD (composite of atherosclerotic CVD and heart failure), include estimated glomerular filtration rate as a predictor, and adjust for competing risk of non-CVD death among adults 30 to 79 years of age. Additional models accommodate enhanced predictive utility with the addition of CKM factors when clinically indicated for measurement (urine albumin-to-creatinine ratio and hemoglobin A1c) or social determinants of health (social deprivation index) when available. Approaches to implement risk-based prevention using PREVENT across various settings are discussed.

Ketone Bodies in Diabetes Mellitus: Friend or Foe?

In glucose-deprived conditions, ketone bodies are produced by the liver mitochondria, through the catabolism of fatty acids, and are used peripherally, as an alternative energy source. Ketones are produced in the body under normal conditions, including during pregnancy and the neonatal period, when following a ketogenic diet (KD), fasting, or exercising. Additionally, ketone synthesis is also augmented under pathological conditions, including cases of diabetic ketoacidosis (DKA), alcoholism, and several metabolic disorders. Nonetheless, diet is the main regulator of total body ketone concentrations. The KDs are mimicking the fasting state, altering the default metabolism towards the use of ketones as the primary fuel source. Recently, KD has gained recognition as a medical nutrition therapy for a plethora of metabolic conditions, including obesity and diabetes mellitus (DM). The present review aims to discuss the role of ketones, KDs, ketonemia, and ketonuria in DM, presenting all the available new evidence in a comprehensive manner.

Metabolic Drivers and Rescuers of Heart Failure

Cardiac hypertrophy and heart failure involve a number of metabolic alterations. Human genetic mutations and murine genetic deficiency models of metabolic enzymes or transporters largely suggest that these alterations in metabolism are maladaptive and contribute to the cardiac remodeling and dysfunction. Here, we discuss insights into metabolic alterations identified in cardiac hypertrophy and failure, as well as dietary and pharmacologic therapies that counteract these metabolic alterations and have been shown to significantly improve heart failure.