Stratification of Atherosclerosis based on Plasma Metabolic States

CONTEXT

Atherosclerosis is a dominant cause of cardiovascular disease (CVD), including myocardial infarction and stroke.

OBJECTIVE

To investigate metabolic states that are associated with the development of atherosclerosis.

METHODS

Cross-sectional cohort study at a university hospital in the Netherlands. A total of 302 adult subjects with a body mass index (BMI) ≥ 27 kg/m2 were included. We integrated plasma metabolomics with clinical metadata to quantify the "atherogenic state" of each individual, providing a continuous spectrum of atherogenic states that ranges between nonatherogenic states to highly atherogenic states.

RESULTS

Analysis of groups of individuals with different clinical conditions-such as metabolically healthy individuals with obesity, and individuals with metabolic syndrome-confirmed the generalizability of this spectrum; revealed a wide variation of atherogenic states within each condition; and allowed identification of metabolites that are associated with the atherogenic state regardless of the particular condition, such as gamma-glutamyl-glutamic acid and homovanillic acid sulfate. The analysis further highlighted metabolic pathways such as catabolism of phenylalanine and tyrosine and biosynthesis of estrogens and phenylpropanoids. Using validation cohorts, we confirmed variation in atherogenic states in healthy subjects (before atherosclerosis plaques become visible), and showed that metabolites associated with the atherogenic state were also associated with future CVD.

CONCLUSION

Our results provide a global view of atherosclerosis risk states using plasma metabolomics.

Clonal hematopoiesis is associated with cardiovascular events in patients with stable coronary artery disease

Clonal hematopoiesis (CH) is a risk factor for atherosclerotic cardiovascular disease, but the impact of smaller clones and the effect on inflammatory parameters is largely unknown. Using ultrasensitive single-molecule molecular inversion probe sequencing, we evaluated the association between CH and a first major adverse cardiovascular event (MACE) in patients with angiographically documented stable coronary artery disease (CAD) and no history of acute ischemic events. CH was associated with an increased rate of MACE at four years follow-up. The size of the clone predicted MACE at an optimal cut-off value of 1.07% variant allele frequency (VAF). Mutation carriers had no change in monocytes subsets or cytokine production capacity but had higher levels of circulating tissue factor, matrilysin, and proteinase-activated receptor-1. Our study identified CH driver mutations with a VAF as small as 1.07% as a residual cardiovascular risk factor and identified potential biomarkers and therapeutic targets for patients with stable CAD.

Cardiometabolic Differences in People Living with HIV Receiving Integrase Strand Transfer Inhibitors Compared to Non-nucleoside Reverse Transcriptase Inhibitors: Implications for Current ART Strategies

In people living with HIV (PLHIV), integrase strand transfer inhibitors (INSTIs) are part of the first-line combination antiretroviral therapy (cART), while non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens are alternatives. Distinct cART regimens may variably influence the risk for non-AIDS comorbidities. We aimed to compare the metabolome and lipidome of INSTI and NNRTI-based regimens. The 2000HIV study includes asymptomatic PLHIV (n = 1646) on long-term cART, separated into a discovery cohort with 730 INSTI and 617 NNRTI users, and a validation cohort encompassing 209 INSTI and 90 NNRTI users. Baseline plasma samples from INSTI and NNRTI users were compared using mass spectrometry-based untargeted metabolomic (n = 500) analysis. Perturbed metabolic pathways were identified using MetaboAnalyst software. Subsequently, nuclear magnetic resonance spectroscopy was used for targeted lipoprotein and lipid (n = 141) analysis. Metabolome homogeneity was observed between the different types of INSTI and NNRTI. In contrast, higher and lower levels of 59 and 45 metabolites, respectively, were found in the INSTI group compared to NNRTI users, of which 77.9% (81/104) had consistent directionality in the validation cohort. Annotated metabolites belonged mainly to 'lipid and lipid-like molecules', 'organic acids and derivatives' and 'organoheterocyclic compounds'. In pathway analysis, perturbed 'vitamin B1 (thiamin) metabolism', 'de novo fatty acid biosynthesis', 'bile acid biosynthesis' and 'pentose phosphate pathway' were detected, among others. Lipoprotein and lipid levels in NNRTIs were heterogeneous and could not be compared as a group. INSTIs compared to individual NNRTI types showed that HDL cholesterol was lower in INSTIs compared to nevirapine but higher in INSTIs compared to doravirine. In addition, LDL size was lower in INSTIs and nevirapine compared to doravirine. NNRTIs show more heterogeneous cardiometabolic effects than INSTIs, which hampers the comparison between these two classes of drugs. Targeted lipoproteomic and lipid NMR spectroscopy showed that INSTI use was associated with a more unfavorable lipid profile compared to nevirapine, which was shifted to a more favorable profile for INSTI when substituting nevirapine for doravirine, with evidently higher fold changes. The cardiovascular disease risk profile seems more favorable in INSTIs compared to NNRTIs in untargeted metabolomic analysis using mass-spectrometry.

Common and distinct metabolomic markers related to immune aging in Western European and East African populations

In old age, impaired immunity causes high susceptibility to infections and cancer, higher morbidity and mortality, and poorer vaccination efficiency. Many factors, such as genetics, diet, and lifestyle, impact aging. This study aimed to investigate how immune responses change with age in healthy Dutch and Tanzanian individuals and identify common metabolites associated with an aged immune profile. We performed untargeted metabolomics from plasma to identify age-associated metabolites, and we correlated their concentrations with ex-vivo cytokine production by immune cells, DNA methylation-based epigenetic aging, and telomere length. Innate immune responses were impacted differently by age in Dutch and Tanzanian cohorts. Age-related decline in steroid hormone precursors common in both populations was associated with higher systemic inflammation and lower cytokine responses. Hippurate and 2-phenylacetamide, commonly more abundant in older individuals, were negatively correlated with cytokine responses and telomere length and positively correlated with epigenetic aging. Lastly, we identified several metabolites that might contribute to the stronger decline in innate immunity with age in Tanzanians. The shared metabolomic signatures of the two cohorts suggest common mechanisms of immune aging, revealing metabolites with potential contributions. These findings also reflect genetic or environmental effects on circulating metabolites that modulate immune responses.

Intermediate monocytes are associated with the first major adverse cardiovascular event in patients with stable coronary artery disease

BACKGROUND

Traditional risk stratification modestly predicts adverse cardiovascular events in patients with coronary artery disease (CAD). Our aim was to investigate the association between monocyte subsets numbers and function, and the first major adverse cardiovascular event (MACE) in patients with symptomatic stable CAD and angiographically documented coronary atherosclerosis.

METHODS

Patients with stable CAD were screened for inclusion. Using flow cytometry, we identified classical, intermediate, and non-classical monocyte subsets and we assessed cytokine production capacity after ex-vivo stimulation of peripheral blood mononuclear cells. Clinical follow-up was performed after four years. The endpoint was the composite of cardiovascular death, acute myocardial infarction, and ischemic stroke.

RESULTS

A cohort of 229 patients was recruited. The percentage of intermediate monocytes was positively associated with adverse cardiovascular events at follow-up (HR 1.09; 95%CI 1.02-1.16; p = 0.006), while the percentage of classical monocytes was identified as a protective factor for adverse outcomes (HR 0.96; 95%CI 0.94-0.99; p = 0.02). The percentage of intermediate monocytes remained independently associated with outcomes after adjusting for age, systolic blood pressure, and left ventricular ejection fraction (HR 1.07; 95% CI 1.01-1.14; p = 0.04). Several correlations were identified between monocyte subsets and stimulated cytokine production, but cytokine production capacity was not associated with adverse outcomes.

CONCLUSIONS

In patients with stable CAD, intermediate monocytes were associated with MACE at follow-up. The association was not due to an increased cytokine production capacity. Novel biomarkers could improve risk stratification in patients with stable CAD and could represent new pharmacological targets against atherosclerosis progression.

Sex-specific association of visceral and subcutaneous adipose tissue volumes with systemic inflammation and innate immune cells in people living with obesity

BACKGROUND AND AIMS

Obesity predisposes to metabolic and cardiovascular diseases. Adipose tissue inflammation and systemic inflammation contribute to these complications. There are strong sex differences in adipose tissue distribution and in systemic inflammation. Women have more subcutaneous adipose tissue (SAT) and less visceral adipose tissue (VAT) than men. We explored the sex differences in the association between the different adipose compartments and inflammatory markers that are important in cardiometabolic disease pathophysiology.

METHODS

Single-center observational cohort study with 302 individuals with a BMI ≥ 27 kg/m2. We were unable to acquire MRI data from seven individuals and from another 18 the MRI data were not usable, resulting in 277 people (155 men, 122 women), aged 55-81 years.

INTERVENTION

We performed the following measurements: abdominal magnetic resonance imaging to measure VAT, and SAT (deep and superficial) volumes; circulating leukocyte counts and cytokine production capacity of peripheral blood mononuclear cells (PBMCs), circulating cytokines, adipokines, and targeted proteomics; abdominal sSAT biopsies for histology and gene expression.

RESULTS

Only in women, (s)SAT volume was associated with circulating leukocytes, monocytes, and neutrophils. Circulating IL-6 and IL-18BP were associated with SAT volume in women and VAT in men. Several circulating proteins, including monocyte-colony-stimulating factor 1 and hepatocyte growth factor, are associated with sSAT in women and VAT in men. Only in women, SAT volume is associated with SAT expression of inflammatory proteins, including leptin, CD68, TNFα and IL-1α.

CONCLUSION

In women living with obesity, abdominal SAT volume, especially sSAT, is associated with circulating leukocytes and inflammatory proteins. In men, these parameters mainly show associations with VAT volume. This could be because only in women, sSAT volume is associated with sSAT expression of inflammatory proteins. These findings underscore that future research on adipose tissue in relation to cardiometabolic and cardiovascular disease should take sex differences into account.

Immune regulation and blood-brain barrier permeability in cerebral small vessel disease: study protocol of the INflammation and Small Vessel Disease (INSVD) study - a multicentre prospective cohort study

INTRODUCTION

The INflammation and Small Vessel Disease (INSVD) study aims to investigate whether peripheral inflammation, immune (dys)regulation and blood-brain barrier (BBB) permeability relate to disease progression in cerebral small vessel disease (SVD). This research aims to pinpoint specific components of the immune response in SVD relating to disease progression. This could identify biomarkers of SVD progression, as well as potential therapeutic targets to inform the development and repurposing of drugs to reduce or prevent SVD, cognitive decline and vascular dementia.

METHODS AND ANALYSIS

INSVD is a prospective observational multicentre cohort study in individuals with symptomatic SVD. This longitudinal study combines comprehensive immunophenotyping of the peripheral blood immune compartment with advanced neuroimaging markers of SVD and BBB permeability. The main SVD marker of interest is white matter microstructure as determined by diffusion tensor imaging, a valuable marker of disease progression owing to its sensitivity to early alterations to white matter integrity. The research is being conducted in two sites-in the UK (Cambridge) and the Netherlands (Nijmegen)-with each site recruiting 100 participants (total n=200). Participants undergo clinical and cognitive assessments, blood draws, and brain MRI at baseline and 2-year follow-up.

ETHICS AND DISSEMINATION

This study received ethical approval from the local ethics boards (UK: East of England-Cambridge Central Research Ethics Committee (REC) ref: 22/EE/00141, Integrated Research Application System (IRAS) ID: 312 747. Netherlands: Medical Research Ethics Committee (MREC) Oost-Nederland, ref: 2022-13623, NL-number: NL80258.091.22). Written informed consent was obtained from all subjects before the study. Any participant-derived benefits resulting from this research, such as new insights into disease mechanisms or possible novel therapies, will be disseminated to study participants, patient groups and members of the public.

TRIAL REGISTRATION NUMBER

NCT05746221.

Innate immune memory in cardiometabolic disease

Low-grade systemic inflammation is a key pathophysiological component of atherosclerotic cardiovascular disease (CVD), and long-term activation of myeloid cells is thought to be crucial for these effects. Obesity and associated metabolic complications including hyperglycaemia and dyslipoproteinaemia can induce long-lasting inflammatory reprogramming of the innate immune cells and their bone marrow progenitors, which in turn contributes to atherosclerosis. In this review, we discuss the mechanisms through which innate immune cells undergo long-term changes in their functional, epigenetic, and metabolic characteristics upon even short-term exposure to endogenous ligands, a process also termed 'trained immunity'. Inappropriate induction of trained immunity leads to the development of long-lasting hyperinflammatory and proatherogenic changes in monocytes and macrophages, an important factor in the development of atherosclerosis and CVDs. Knowledge of the specific immune cells and the distinct intracellular molecular pathways involved in the induction of trained immunity will reveal novel pharmacological targets that could be used to prevent or treat CVDs in the future.

The effect of leptin on trained innate immunity and on systemic inflammation in subjects with obesity

Leptin is associated with cardiometabolic complications of obesity, such as metabolic syndrome and atherosclerosis. In obese men, the presence of metabolic syndrome is associated with higher circulating leptin and interleukin (IL)-6 concentrations and increased monocyte cytokine production capacity. Here, we investigated the effects of leptin on monocyte function and systemic inflammatory markers in obese individuals. We specifically explored whether leptin can induce long-term changes in innate immune function by inducing innate immune memory (also called trained immunity). We exposed human primary monocytes for 24 h to relevant leptin concentrations in vitro and measured cytokine production. In addition, after removing leptin, we incubated monocytes for 5 d in culture medium, and we restimulated them on day 6 to assess cytokine production capacity, phagocytosis, and foam cell formation. Direct stimulation with leptin did not induce cytokine production, but exposure to 50 ng/mL leptin augmented lipopolysaccharide- and R848-induced tumor necrosis factor α (TNF-α) production after 1 wk. In a separate in vivo study in a cohort of 302 obese subjects (body mass index [BMI] >27 kg/m2, 55 to 81 yr), we measured circulating leptin, inflammatory markers, and cytokine production upon ex vivo stimulation of isolated peripheral blood mononuclear cells. Circulating leptin concentrations positively correlated with circulating IL-1β and IL-6, which was more pronounced in men than in women. Four single nucleotide polymorphisms in the leptin gene influenced circulating IL-6 concentrations in men, suggesting a direct effect of leptin on IL-6. In conclusion, in vitro, leptin does not directly stimulate monocytes to produce cytokines, yet induces long-term monocyte hyperresponsiveness, i.e. trained immunity. In obese subjects, leptin is associated with circulating IL-6 in a sex-dependent manner. The underlying mechanisms of the sex-specific effect of leptin on innate immune cells remain to be further investigated.

Association Between Clonal Hematopoiesis Driver Mutations, Immune Cell Function, and the Vasculometabolic Complications of Obesity

BACKGROUND

Obesity is accompanied by dysregulated inflammation, which can contribute to vasculometabolic complications including metabolic syndrome and atherosclerosis. Recently, clonal hematopoiesis of indeterminate potential (CHIP) has emerged as a risk factor for cardiovascular diseases. We aimed to determine how CHIP is related to immune cell function, systemic inflammation, and vasculometabolic complications in obese individuals.

METHODS AND RESULTS

Two hundred ninety-seven individuals with overweight and obesity, between the ages of 54 and 81 years, were recruited in a cross-sectional study. Clonal hematopoiesis driver mutations (CHDMs) were identified with an ultrasensitive targeted assay. Assessment of carotid artery atherosclerosis was performed with ultrasound. Detailed immunological parameters, including cytokine production capacity of peripheral blood mononuclear cells, and targeted plasma proteomics analysis, were studied. Adipose tissue inflammation was determined in subcutaneous fat biopsies. Individuals with CHIP had higher concentrations of circulating IL (interleukin)-6. Total number of leukocytes and neutrophils were higher in individuals with CHIP. In contrast, ex vivo cytokine production capacity of peripheral blood mononuclear cells was significantly lower in individuals with CHIP. Sex-stratified analysis showed that men with CHDMs had significantly higher leukocyte and neutrophil counts, and ex vivo cytokine production capacity was lower in women with CHDMs. Surprisingly, the presence of atherosclerotic plaques was significantly lower in individuals with CHDMs. There was no relation between CHIP and metabolic syndrome.

CONCLUSIONS

In individuals with overweight or obesity, CHDMs are not associated with vasculometabolic complications, but rather with a lower presence of carotid plaques. CHDMs associate with increased circulating inflammatory markers and leukocyte numbers, but a lower peripheral blood mononuclear cell cytokine production capacity.

Host genetic regulation of human gut microbial structural variation

Although the impact of host genetics on gut microbial diversity and the abundance of specific taxa is well established1-6, little is known about how host genetics regulates the genetic diversity of gut microorganisms. Here we conducted a meta-analysis of associations between human genetic variation and gut microbial structural variation in 9,015 individuals from four Dutch cohorts. Strikingly, the presence rate of a structural variation segment in Faecalibacterium prausnitzii that harbours an N-acetylgalactosamine (GalNAc) utilization gene cluster is higher in individuals who secrete the type A oligosaccharide antigen terminating in GalNAc, a feature that is jointly determined by human ABO and FUT2 genotypes, and we could replicate this association in a Tanzanian cohort. In vitro experiments demonstrated that GalNAc can be used as the sole carbohydrate source for F. prausnitzii strains that carry the GalNAc-metabolizing pathway. Further in silico and in vitro studies demonstrated that other ABO-associated species can also utilize GalNAc, particularly Collinsella aerofaciens. The GalNAc utilization genes are also associated with the host's cardiometabolic health, particularly in individuals with mucosal A-antigen. Together, the findings of our study demonstrate that genetic associations across the human genome and bacterial metagenome can provide functional insights into the reciprocal host-microbiome relationship.

Acid ceramidase regulates innate immune memory

Innate immune memory, also called "trained immunity," is a functional state of myeloid cells enabling enhanced immune responses. This phenomenon is important for host defense, but also plays a role in various immune-mediated conditions. We show that exogenously administered sphingolipids and inhibition of sphingolipid metabolizing enzymes modulate trained immunity. In particular, we reveal that acid ceramidase, an enzyme that converts ceramide to sphingosine, is a potent regulator of trained immunity. We show that acid ceramidase regulates the transcription of histone-modifying enzymes, resulting in profound changes in histone 3 lysine 27 acetylation and histone 3 lysine 4 trimethylation. We confirm our findings by identifying single-nucleotide polymorphisms in the region of ASAH1, the gene encoding acid ceramidase, that are associated with the trained immunity cytokine response. Our findings reveal an immunomodulatory effect of sphingolipids and identify acid ceramidase as a relevant therapeutic target to modulate trained immunity responses in innate immune-driven disorders.

Trained immunity in atherosclerotic cardiovascular disease

Trained immunity, also known as innate immune memory, is a persistent hyper-responsive functional state of innate immune cells. Accumulating evidence implicates trained immunity as an underlying mechanism of chronic inflammation in atherosclerotic cardiovascular disease. In this context, trained immunity is induced by endogenous atherosclerosis-promoting factors, such as modified lipoproteins or hyperglycaemia, causing broad metabolic and epigenetic reprogramming of the myeloid cell compartment. In addition to traditional cardiovascular risk factors, lifestyle factors, including unhealthy diets, sedentary lifestyle, sleep deprivation and psychosocial stress, as well as inflammatory comorbidities, have been shown to activate trained immunity-like mechanisms in bone marrow haematopoietic stem cells. In this Review, we discuss the molecular and cellular mechanisms of trained immunity, its systemic regulation through haematopoietic progenitor cells in the bone marrow, and the activation of these mechanisms by cardiovascular disease risk factors. We also highlight other trained immunity features that are relevant for atherosclerotic cardiovascular disease, including the diverse cell types that show memory characteristics and transgenerational inheritance of trained immunity traits. Finally, we propose potential strategies for the therapeutic modulation of trained immunity to manage atherosclerotic cardiovascular disease.

Traditional Cardiovascular Risk Factors Are Stronger Related to Carotid Intima-Media Thickness Than to Presence of Carotid Plaques in People Living With HIV

Background Cardiovascular disease is a major cause of morbidity and mortality in people living with HIV, who are at higher risk than the general population. We assessed, in a large cohort of people living with HIV, which cardiovascular, HIV-specific, and lipoproteomic markers were associated with carotid intima-media thickness (cIMT) and carotid plaque presence. We also studied guideline adherence on lipid-lowering medication in individuals with high and very high risk for cardiovascular disease. Methods and Results In 1814 individuals with a median (interquartile range) age of 53 (44-60) years, we found a carotid plaque in 909 (50.1%) and a median (interquartile range) intima-media thickness of 0.66 (0.57-0.76) mm. Ultrasonography was used for the assessment of cIMT and plaque presence. Univariable and multivariable regression models were used for associations with cIMT and presence of plaques. Age, Black race, body mass index, type 2 diabetes, and smoking (pack years) were all positively associated with higher cIMT. Levels of high-density lipoprotein cholesterol, specifically medium and large high-density lipoprotein subclasses, were negatively associated with higher cIMT. Only age and prior myocardial infarction were positively related to the presence of a carotid plaque. Lipid-lowering treatment was prescribed in one-third of people living with HIV, who are at high and very high risk for cardiovascular disease. Conclusions Traditional cardiovascular risk factors were significantly associated with higher cIMT but not with carotid plaques, except for age. HIV-specific factors were not associated with both ultrasound measurements. Future studies are needed to elucidate which factors contribute to plaque formation. Improvement of guideline adherence on prescription of lipid-lowering treatment in high- and very high-risk patients for cardiovascular disease is recommended. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03994835.

The optimal healthy ranges of thyroid function defined by the risk of cardiovascular disease and mortality: systematic review and individual participant data meta-analysis

BACKGROUND

Reference intervals of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) are statistically defined by the 2·5-97·5th percentiles, without accounting for potential risk of clinical outcomes. We aimed to define the optimal healthy ranges of TSH and FT4 based on the risk of cardiovascular disease and mortality.

METHODS

This systematic review and individual participant data (IPD) meta-analysis identified eligible prospective cohorts through the Thyroid Studies Collaboration, supplemented with a systematic search via Embase, MEDLINE (Ovid), Web of science, the Cochrane Central Register of Controlled Trials, and Google Scholar from Jan 1, 2011, to Feb 12, 2017 with an updated search to Oct 13, 2022 (cohorts found in the second search were not included in the IPD). We included cohorts that collected TSH or FT4, and cardiovascular outcomes or mortality for adults (aged ≥18 years). We excluded cohorts that included solely pregnant women, individuals with overt thyroid diseases, and individuals with cardiovascular disease. We contacted the study investigators of eligible cohorts to provide IPD on demographics, TSH, FT4, thyroid peroxidase antibodies, history of cardiovascular disease and risk factors, medication use, cardiovascular disease events, cardiovascular disease mortality, and all-cause mortality. The primary outcome was a composite outcome including cardiovascular disease events (coronary heart disease, stroke, and heart failure) and all-cause mortality. Secondary outcomes were the separate assessment of cardiovascular disease events, all-cause mortality, and cardiovascular disease mortality. We performed one-step (cohort-stratified Cox models) and two-step (random-effects models) meta-analyses adjusting for age, sex, smoking, systolic blood pressure, diabetes, and total cholesterol. The study was registered with PROSPERO, CRD42017057576.

FINDINGS

We identified 3935 studies, of which 53 cohorts fulfilled the inclusion criteria and 26 cohorts agreed to participate. We included IPD on 134 346 participants with a median age of 59 years (range 18-106) at baseline. There was a J-shaped association of FT4 with the composite outcome and secondary outcomes, with the 20th (median 13·5 pmol/L [IQR 11·2-13·9]) to 40th percentiles (median 14·8 pmol/L [12·3-15·0]) conveying the lowest risk. Compared with the 20-40th percentiles, the age-adjusted and sex-adjusted hazard ratio (HR) for FT4 in the 80-100th percentiles was 1·20 (95% CI 1·11-1·31) for the composite outcome, 1·34 (1·20-1·49) for all-cause mortality, 1·57 (1·31-1·89) for cardiovascular disease mortality, and 1·22 (1·11-1·33) for cardiovascular disease events. In individuals aged 70 years and older, the 10-year absolute risk of composite outcome increased over 5% for women with FT4 greater than the 85th percentile (median 17·6 pmol/L [IQR 15·0-18·3]), and men with FT4 greater than the 75th percentile (16·7 pmol/L [14·0-17·4]). Non-linear associations were identified for TSH, with the 60th (median 1·90 mIU/L [IQR 1·68-2·25]) to 80th percentiles (2·90 mIU/L [2·41-3·32]) associated with the lowest risk of cardiovascular disease and mortality. Compared with the 60-80th percentiles, the age-adjusted and sex-adjusted HR of TSH in the 0-20th percentiles was 1·07 (95% CI 1·02-1·12) for the composite outcome, 1·09 (1·05-1·14) for all-cause mortality, and 1·07 (0·99-1·16) for cardiovascular disease mortality.

INTERPRETATION

There was a J-shaped association of FT4 with cardiovascular disease and mortality. Low concentrations of TSH were associated with a higher risk of all-cause mortality and cardiovascular disease mortality. The 20-40th percentiles of FT4 and the 60-80th percentiles of TSH could represent the optimal healthy ranges of thyroid function based on the risk of cardiovascular disease and mortality, with more than 5% increase of 10-year composite risk identified for FT4 greater than the 85th percentile in women and men older than 70 years. We propose a feasible approach to establish the optimal healthy ranges of thyroid function, allowing for better identification of individuals with a higher risk of thyroid-related outcomes.

FUNDING

None.

Sex-specific Association Between Adipose Tissue Inflammation and Vascular and Metabolic Complications of Obesity

CONTEXT

Adipose tissue (AT) inflammation predisposes to insulin resistance and metabolic syndrome in obesity.

OBJECTIVE

To investigate the association between adipocyte size, AT inflammation, systemic inflammation, and metabolic and atherosclerotic complications of obesity in a sex-specific manner.

DESIGN

Cross-sectional cohort study.

SETTING

University hospital in the Netherlands.

PARTICIPANTS

A total of 302 adult subjects with a body mass index (BMI) ≥ 27 kg/m2.

MAIN OUTCOME MEASURES

We obtained subcutaneous abdominal fat biopsies and systematically assessed, in a sex-specific manner, associations of several parameters of AT inflammation (including adipocyte size, macrophage content, crown-like structures, and gene expression) to biomarkers of systemic inflammation, leukocyte number and function, and to the presence of metabolic syndrome, insulin resistance, and carotid atherosclerotic plaques, assessed with ultrasound.

RESULTS

Adipocyte size was associated with metabolic syndrome and AT macrophage content with insulin resistance. In contrast, none of the AT parameters was associated with carotid atherosclerosis, although mRNA expression of the anti-inflammatory IL-37 was associated with a lower intima-media thickness. We revealed profound sex-specific differences, with an association between BMI and adipocyte size, and between adipocyte size and metabolic syndrome in men only. Also, only men showed an association between adipocyte size, AT expression of leptin and MCP-1, and AT macrophage numbers, and between AT inflammation (crown-like structure number) and several circulating inflammatory proteins, including high specificity C-reactive protein, and IL-6.

CONCLUSIONS

Inflammation in abdominal subcutaneous adipose tissue is more related to the metabolic than the atherosclerotic complications of obesity, and there are profound sex-specific differences in the association between BMI, adipocyte size, AT inflammation, and systemic inflammation, which are much stronger in men than women.

Composition and distribution of lipoproteins after evolocumab in familial dysbetalipoproteinemia: A randomized controlled trial

BACKGROUND

Proprotein convertase subtilisin kexin type 9 (PCSK9) monoclonal antibodies (mAbs) reduce fasting and post fat load cholesterol in non-HDL and intermediate density lipoprotein (IDL) in familial dysbetalipoproteinemia (FD). However, the effect of PCSK9 mAbs on the distribution and composition of atherogenic lipoproteins in patients with FD is unknown.

OBJECTIVE

To evaluate the effect of the PCSK9 mAb evolocumab added to standard lipid-lowering therapy in patients with FD on fasting and post fat load lipoprotein distribution and composition.

METHODS

Randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. Patients received an oral fat load at the start and end of each treatment period. Apolipoproteins (apo) were measured with ultracentrifugation, gradient gel electrophoresis, retinyl palmitate and SDS-PAGE.

RESULTS

PCSK9 mAbs significantly reduced particle number of all atherogenic lipoproteins, with a stronger effect on smaller lipoproteins than on larger lipoproteins (e.g. IDL-apoB 49%, 95%confidence interval (CI) 41-59 and very low-density lipoprotein (VLDL)-apoB 33%, 95%CI 16-50). Furthermore, PCSK9 mAbs lowered cholesterol more than triglyceride (TG) in VLDL, IDL and low-density lipoprotein (LDL) (e.g. VLDL-C 48%, 95%CI 29-63%; and VLDL-TG 20%, 95%CI 6.3-41%). PCSK9 mAbs did not affect the post fat load response of chylomicrons.

CONCLUSION

PCSK9 mAbs added to standard lipid-lowering therapy in FD patients significantly reduced lipoprotein particle number, in particular the smaller and more cholesterol-rich lipoproteins (i.e. IDL and LDL). PCSK9 mAbs did not affect chylomicron metabolism. It seems likely that the observed effects are achieved by increased hepatic lipoprotein clearance, but the specific working mechanism of PCSK9 mAbs in FD patients remains to be elucidated.

Clonal Hematopoiesis Has Prognostic Value in Dilated Cardiomyopathy Independent of Age and Clone Size

BACKGROUND

Clonal hematopoiesis (CH) gives rise to mutated leukocyte clones that induce cardiovascular inflammation and thereby impact the disease course in atherosclerosis and ischemic heart failure. CH of indeterminate potential refers to a variant allele frequency (VAF; a marker for clone size) in blood of ≥2%. The impact of CH clones-including small clone sizes (VAF <0.5%)-in nonischemic dilated cardiomyopathy (DCM) remains largely undetermined.

OBJECTIVES

The authors sought to establish the prognostic impact of CH in DCM including small clones.

METHODS

CH is determined using an ultrasensitive single-molecule molecular inversion probe technique that allows detection of clones down to a VAF of 0.01%. Cardiac death and all-cause mortality were analyzed using receiver-operating characteristic curve-optimized VAF cutoff values.

RESULTS

A total of 520 DCM patients have been included. One hundred and nine patients (21%) had CH driver mutations, of which 45 had a VAF of ≥2% and 31 <0.5%. The median follow-up duration was 6.5 years [IQR: 4.7-9.7 years]. DCM patients with CH have a higher risk of cardiac death (HR: 2.33 using a VAF cutoff of 0.36%, 95% CI: 1.24-4.40) and all-cause mortality (HR: 1.72 using a VAF cutoff of 0.06%, 95% CI: 1.10-2.69), independent of age, sex, left ventricular ejection fraction, and New York Heart Association classification.

CONCLUSIONS

CH predicts cardiac death and all-cause mortality in DCM patients with optimal thresholds for clone size of 0.36% and 0.06%, respectively. Therefore, CH is prognostically relevant, independent of clone size in patients with DCM.

Arterial wall inflammation assessed by 18F-FDG-PET/CT is higher in individuals with Type 1 diabetes and associated with circulating inflammatory proteins

AIMS

The article investigates whether chronic hyperglycaemia in Type 1 diabetes (T1D) is associated with a proinflammatory immune signature and with arterial wall inflammation, driving the development of atherosclerosis.

METHODS AND RESULTS

Patients with T1D (n = 41), and healthy age-, sex-, and body mass index-matched controls (n = 20) were recruited. Arterial wall inflammation and haematopoietic activity were measured with 2'-deoxy-2'-(18F)-fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography. In addition, flow cytometry of circulating leucocytes was performed as well as targeted proteomics to measure circulating inflammatory markers. 18F-FDG uptake in the wall of the abdominal aorta, carotid arteries, and iliac arteries was higher in T1D compared with that in the healthy controls. Also, 18F-FDG uptake in the bone marrow and spleen was higher in patients with T1D. CCR2 and CD36 expressions on circulating monocytes were higher in patients with T1D, as well as several circulating inflammatory proteins. In addition, several circulating inflammatory markers (osteoprotegerin, transforming growth factor-alpha, CX3CL1, and colony-stimulating factor-1) displayed a positive correlation with FDG uptake. Within T1D, no differences were found between people with a high and low HbA1c.

CONCLUSION

These findings strengthen the concept that chronic hyperglycaemia in T1D induces inflammatory changes that fuel arterial wall inflammation leading to atherosclerosis. The degree of hyperglycaemia appears to play a minor role in driving this inflammatory response in patients with T1D.

Clonal Hematopoiesis of Indeterminate Potential From a Heart Failure Specialist's Point of View

Clonal hematopoiesis of indeterminate potential (CHIP) is a common bone marrow abnormality induced by age-related DNA mutations, which give rise to proinflammatory immune cells. These immune cells exacerbate atherosclerotic cardiovascular disease and may induce or accelerate heart failure. The mechanisms involved are complex but point toward a central role for proinflammatory macrophages and an inflammasome-dependent immune response (IL-1 [interleukin-1] and IL-6 [interleukin-6]) in the atherosclerotic plaque or directly in the myocardium. Intracardiac inflammation may decrease cardiac function and induce cardiac fibrosis, even in the absence of atherosclerotic cardiovascular disease. The pathophysiology and consequences of CHIP may differ among implicated genes as well as subgroups of patients with heart failure, based on cause (ischemic versus nonischemic) and ejection fraction (reduced ejection fraction versus preserved ejection fraction). Evidence is accumulating that CHIP is associated with cardiovascular mortality in ischemic and nonischemic heart failure with reduced ejection fraction and involved in the development of heart failure with preserved ejection fraction. CHIP and corresponding inflammatory pathways provide a highly potent therapeutic target. Randomized controlled trials in patients with well-phenotyped heart failure, where readily available anti-inflammatory therapies are used to intervene with clonal hematopoiesis, may pave the way for a new area of heart failure treatment. The first clinical trials that target CHIP are already registered.

Peripheral blood mononuclear cell hyperresponsiveness in patients with premature myocardial infarction without traditional risk factors

An increasing number of patients develop an atherothrombotic myocardial infarction (MI) in the absence of standard modifiable risk factors (SMuRFs). Monocytes and macrophages regulate the development of atherosclerosis, and monocytes can adopt a long-term hyperinflammatory phenotype by epigenetic reprogramming, which can contribute to atherogenesis (called "trained immunity"). We assessed circulating monocyte phenotype and function and specific histone marks associated with trained immunity in SMuRFless patients with MI and matched healthy controls. Even in the absence of systemic inflammation, monocytes from SMuRFless patients with MI had an increased overall cytokine production capacity, with the strongest difference for LPS-induced interleukin-10 production, which was associated with an enrichment of the permissive histone marker H3K4me3 at the promoter region. Considering the lack of intervenable risk factors in these patients, trained immunity could be a promising target for future therapy.

Low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol measurement in Familial Dysbetalipoproteinemia

AIM

To compare LDL-C concentrations using the Friedewald formula, the Martin-Hopkins formula, a direct assay and polyacrylamide gradient gel electrophoresis (PGGE) to the reference standard density gradient ultracentrifugation in patients with Familial Dysbetalipoproteinemia (FD) patients. We also compared non-HDL-cholesterol concentrations by two methods.

METHODS

For this study data from 28 patients with genetically confirmed FD from the placebo arm of the EVOLVE-FD trial were used. Four different methods for determining LDL-C were compared with ultracentrifugation. Non-HDL-C was measured with standard assays and compared to ultracentrifugation. Correlation coefficients and Bland-Altman plots were used to compare the methods.

RESULTS

Mean age of the 28 FD patients was 62 ± 9 years, 43 % were female and 93 % had an ɛ2ɛ2 genotype. LDL-C determined by Friedewald (R² = 0.62, p <0.01), Martin-Hopkins (R² = 0.50, p = 0.01) and the direct assay (R² = 0.41, p = 0.03) correlated with density gradient ultracentrifugation. However, Bland-Altman plots showed considerable over- or underestimation by the four methods compared to ultracentrifugation. Non-HDL-C showed good correlation and agreement.

CONCLUSION

In patients with FD, all four methods investigated over- or underestimated LDL-C concentrations compared with ultracentrifugation. In contrast, standard non-HDL-C assays performed well, emphasizing the use of non-HDL-C in patients with FD.

Editor's Choice - Therapeutic Options and Outcomes in Midaortic Syndrome: A Systematic Review and Meta-analysis

OBJECTIVE

Midaortic syndrome (MAS) is narrowing of the distal thoracic and or abdominal aorta with congenital, inflammatory, or idiopathic aetiology. If left untreated, the prognosis is poor due to hypertensive complications. Follow up data after treatment are sparse, contrary to aortic coarctation. This study aimed to investigate hypertension during follow up after medical, endovascular, and surgical therapy in juveniles and adults.

DATA SOURCES

A meta-analysis of case series and reports was performed, focusing on the incidence of hypertension during the follow up of juvenile (i.e., age 0-17 years) and adult MAS patients after medical, endovascular, or surgical therapy.

REVIEW METHODS

Search queries were performed in PubMed, Embase, and Web of Science, and eligible articles underwent quality control. Descriptive statistics were reported based on available data, and individual patient data meta-analyses were performed using a one stage approach, accounting for clustering by case series or decades of reporting for case reports. For the meta-analysis, missing outcome and aetiology data were multiply imputed.

RESULTS

The number of juveniles and adults who underwent endovascular therapy (33.7% vs. 27.3%; p = .42) and surgery (52.2% vs. 58.0%; p = .46) was similar. At baseline, 92.4% of juveniles and 87.5% of adults were hypertensive, decreasing to 23.2% and 24.1% during a follow up of 23 months (juveniles) and 18 months (adults), respectively. More hypertension was found compared with surgery in juveniles after endovascular therapy (38.1% vs. 10.8%; p = .020). Meta-analysis also demonstrated a trend for hypertension after endovascular therapy in juveniles, whereas hypertension was more prevalent following surgery in adults compared with endovascular therapy or medication.

CONCLUSION

This review and meta-analysis investigated therapeutic options for MAS in juveniles and adults. It found that complications and hypertension during follow up were more common in juveniles after endovascular treatment, whereas surgery in adults was associated with more hypertension.

Effect of evolocumab on fasting and post fat load lipids and lipoproteins in familial dysbetalipoproteinemia

BACKGROUND

Familial dysbetalipoproteinemia (FD) is the second most common monogenic lipid disorder (prevalence 1 in 850-3500), characterized by postprandial remnant accumulation and associated with increased cardiovascular disease (CVD) risk. Many FD patients do not achieve non-HDL-C treatment goals, indicating the need for additional lipid-lowering treatment options.

OBJECTIVES

To evaluate the effect of the PCSK9 monoclonal antibody evolocumab added to standard lipid-lowering therapy on fasting and post fat load lipids and lipoproteins in patients with FD.

METHODS

A randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. At the start and end of each treatment period patients received an oral fat load. The primary endpoint was the 8-hour post fat load non-HDL-C area under the curve (AUC). Secondary endpoints included fasting and post fat load lipids and lipoproteins.

RESULTS

In total, 28 patients completed the study. Mean age was 62±9 years and 93% had an Ɛ2Ɛ2 genotype. Evolocumab reduced the 8-hour post fat load non-HDL-C AUC with 49% (95%CI 42-55) and apolipoprotein B (apoB) AUC with 47% (95%CI 41-53). Other fasting and absolute post fat load lipids and lipoproteins including triglycerides and remnant-cholesterol were also significantly reduced by evolocumab. However, evolocumab did not have significant effects on the rise above fasting levels that occurred after consumption of the oral fat load.

CONCLUSIONS

Evolocumab added to standard lipid-lowering therapy significantly reduced fasting and absolute post fat load concentrations of non-HDL-C, apoB and other atherogenic lipids and lipoproteins in FD patients. The clinically significant decrease in lipids and lipoproteins can be expected to translate into a reduction in CVD risk in these high-risk patients.

Systematic analysis of relationships between plasma branched-chain amino acid concentrations and cardiometabolic parameters: an association and Mendelian randomization study

BACKGROUND

Branched-chain amino acids (BCAAs; valine, leucine, and isoleucine) are essential amino acids that are associated with an increased risk of cardiometabolic diseases (CMD). However, there are still only limited insights into potential direct associations between BCAAs and a wide range of CMD parameters, especially those remaining after correcting for covariates and underlying causal relationships.

METHODS

To shed light on these relationships, we systematically characterized the associations between plasma BCAA concentrations and a large panel of 537 CMD parameters (including atherosclerosis-related parameters, fat distribution, plasma cytokine concentrations and cell counts, circulating concentrations of cardiovascular-related proteins and plasma metabolites) in 1400 individuals from the Dutch population cohort LifeLines DEEP and 294 overweight individuals from the 300OB cohort. After correcting for age, sex, and BMI, we assessed associations between individual BCAAs and CMD parameters. We further assessed the underlying causality using Mendelian randomization.

RESULTS

A total of 838 significant associations were detected for 409 CMD parameters. BCAAs showed both common and specific associations, with the most specific associations being detected for isoleucine. Further, we found that obesity status substantially affected the strength and direction of associations for valine, which cannot be corrected for using BMI as a covariate. Subsequent univariable Mendelian randomization (UVMR), after removing BMI-associated SNPs, identified seven significant causal relationships from four CMD traits to BCAA levels, mostly for diabetes-related parameters. However, no causal effects of BCAAs on CMD parameters were supported.

CONCLUSIONS

Our cross-sectional association study reports a large number of associations between BCAAs and CMD parameters. Our results highlight some specific associations for isoleucine, as well as obesity-specific effects for valine. MR-based causality analysis suggests that altered BCAA levels can be a consequence of diabetes and alteration in lipid metabolism. We found no MR evidence to support a causal role for BCAAs in CMD. These findings provide evidence to (re)evaluate the clinical importance of individual BCAAs in CMD diagnosis, prevention, and treatment.

Effect of ticagrelor and prasugrel on remote myocardial inflammation in patients with acute myocardial infarction with ST-elevation: a CMR T1 and T2 mapping study

PURPOSE

Acute myocardial ischaemia triggers a non-specific inflammatory response of remote myocardium through the increase of plasma concentrations of acute-phase proteins, which causes myocardial oedema. As ticagrelor has been shown to significantly decrease circulating levels of several pro-inflammatory cytokines in patients after acute myocardial infarction with ST-elevation (STEMI), we sought to investigate a potential suppressive effect of ticagrelor over prasugrel on cardiac magnetic resonance (CMR) T1 and T2 values in remote myocardium.

METHODS

Ninety STEMI patients were prospectively included and randomised to receive either ticagrelor or prasugrel maintenance treatment after successful primary percutaneous coronary intervention. Patients underwent CMR after 2-7 days. The protocol included long and short axis cine imaging, T1 mapping, T2 mapping and late gadolinium enhancement imaging.

RESULTS

After excluding 30 patients due to either missing images or insufficient quality of the T1 or T2 maps, 60 patients were included in our analysis. Of those, 29 patients were randomised to the ticagrelor group and 31 patients to the prasugrel group. In the remote myocardium, T1 values did not differ between groups (931.3 [919.4-950.4] ms for ticagrelor vs. 932.6 [915.5-949.2] ms for prasugrel (p = 0.94)), nor did the T2 values (53.8 ± 4.6 ms for ticagrelor vs. 53.7 ± 4.7 ms for prasugrel (p = 0.86)). Also, in the infarcted myocardium, T1 and T2 values did not differ between groups.

CONCLUSION

In revascularised STEMI patients, ticagrelor maintenance therapy did not show superiority over prasugrel in preventing early remote myocardial inflammation as assessed by CMR T1 and T2 mapping.

Effect of evolocumab versus placebo added to standard lipid-lowering therapy on fasting and post fat load lipids and lipoproteins in familial dysbetalipoproteinemia

Background

Familial Dysbetalipoproteinemia (FD) is the second most common genetic lipid disorder (prevalence ranging from 1 in 1000–2500), characterized by impaired postprandial lipoprotein clearance and associated with increased cardiovascular (CVD) risk. The majority of FD patients do not achieve non-HDL-cholesterol treatment goals, indicating the medical need for additional lipid-lowering treatment options.

Purpose

To evaluate the effect of the PCSK9 monoclonal antibody evolocumab added to standard lipid-lowering therapy on fasting and post fat load lipids and lipoproteins in FD patients.

Methods

A randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12 week treatment periods. At the start and end of each treatment period FD patients received an oral fat load. The primary endpoint was the 8 hour post fat load non-HDL-cholesterol level expressed as area under the curve (AUC). Levels of other fasting and post fat load lipids and (apo)lipoproteins were assessed with ultracentrifugation, polyacrylamide gels, retinyl palmitate and SDS-PAGE.

Results

In total, 28 patients completed the study. Mean age was 62±9 years and 93% had an ɛ2ɛ2 genotype. Compared with placebo, evolocumab reduced fasting non-HDL-cholesterol with 51% (95% CI 43–57) and the 8 hours post fat load non-HDL-cholesterol AUC with 49% (95% CI 42–55). Fasting triglyceride levels were reduced with 24% (95% CI 14–37) and the 8 hours post fat load triglyceride AUC was reduced with 22% (95% CI 11–29). Except for HDL-cholesterol, all fasting and 8 hour post fat load lipids and (apo)lipoproteins were significantly reduced by evolocumab, including apolipoprotein B (8 hour post fat load AUC reduction 47% (95% CI 41–53) and remnant cholesterol (8 hour post fat load AUC reduction 49% (95% CI −38 to 59)), compared with placebo. After treatment with evolocumab, 89% of patients achieved their non-HDL-cholesterol treatment goal compared with 36% after placebo.

Conclusion

Evolocumab added to standard lipid-lowering therapy significantly reduced fasting and post fat load non-HDL-cholesterol and other atherogenic lipids and lipoproteins in FD patients. This is the largest clinical trial in FD to date and the first to investigate evolocumab in this very high-risk group. The large decrease in fasting and post fat load lipids and lipoproteins will likely lower CVD risk in these patients.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): AmgenThis project was funded by Amgen for an investigator-initiated research project. The University Medical Center Utrecht was the sponsor of the study. The financial funder had no role in the design, collection of the data, conduct of the analyses or reporting of the study results.

A role for artificial intelligence in molecular imaging of infection and inflammation

The detection of occult infections and low-grade inflammation in clinical practice remains challenging and much depending on readers’ expertise. Although molecular imaging, like [¹⁸F]FDG PET or radiolabeled leukocyte scintigraphy, offers quantitative and reproducible whole body data on inflammatory responses its interpretation is limited to visual analysis. This often leads to delayed diagnosis and treatment, as well as untapped areas of potential application. Artificial intelligence (AI) offers innovative approaches to mine the wealth of imaging data and has led to disruptive breakthroughs in other medical domains already. Here, we discuss how AI-based tools can improve the detection sensitivity of molecular imaging in infection and inflammation but also how AI might push the data analysis beyond current application toward predicting outcome and long-term risk assessment.

Antithrombotic Therapy for Symptomatic Peripheral Arterial Disease: A Systematic Review and Network Meta-Analysis

Background

High-quality evidence from trials directly comparing single antiplatelet therapies in symptomatic peripheral arterial disease (PAD) to dual antiplatelet therapies or acetylsalicylic acid (ASA) plus low-dose rivaroxaban is lacking. Therefore, we conducted a network meta-analysis on the effectiveness of all antithrombotic regimens studied in PAD.

Methods

A systematic search was conducted to identify randomized controlled trials. The primary endpoints were major adverse cardiovascular events (MACE) and major bleedings. Secondary endpoints were major adverse limb events (MALE) and acute limb ischaemia (ALI). For each outcome, a frequentist network meta-analysis was used to compare relative risks (RRs) between medication and ASA. ASA was the universal comparator since a majority of studies used ASA as in the reference group.

Results

Twenty-four randomized controlled trials were identified including 48,759 patients. With regard to reducing MACE, clopidogrel [RR 0.78, 95% confidence interval (CI) 0.66–0.93], ticagrelor (RR 0.79, 95% CI 0.65–0.97), ASA plus ticagrelor (RR 0.79, 95% CI 0.64–0.97), and ASA plus low-dose rivaroxaban (RR 0.84, 95% CI 0.76–0.93) were more effective than ASA, and equally effective to one another. As compared to ASA, major bleedings occurred more frequently with vitamin K antagonists, rivaroxaban, ASA plus vitamin K antagonists, and ASA plus low-dose rivaroxaban. All regimens were similar to ASA concerning MALE, while ASA plus low-dose rivaroxaban was more effective in preventing ALI (RR 0.67, 95% CI 0.55–0.80). Subgroup analysis in patients undergoing peripheral revascularization revealed that ≥ 3 months after intervention, evidence of benefit regarding clopidogrel, ticagrelor, and ASA plus ticagrelor was lacking, while ASA plus low-dose rivaroxaban was more effective in preventing MACE (RR 0.87, 95% CI 0.78–0.97) and MALE (RR 0.89, 95% CI 0.81–0.97) compared to ASA. ASA plus clopidogrel was not superior to ASA in preventing MACE ≥ 3 months after revascularization. Evidence regarding antithrombotic treatment strategies within 3 months after a peripheral intervention was lacking.

Conclusion

Clopidogrel, ticagrelor, ASA plus ticagrelor, and ASA plus low-dose rivaroxaban are superior to ASA monotherapy and equally effective to one another in preventing MACE in PAD. Of these four therapies, only ASA plus low-dose rivaroxaban provides a higher risk of major bleedings. More than 3 months after peripheral vascular intervention, ASA plus low-dose rivaroxaban is superior in preventing MACE and MALE compared to ASA but again at the cost of a higher risk of bleeding, while other treatment regimens show non-superiority. Based on the current evidence, clopidogrel may be considered the antithrombotic therapy of choice for most PAD patients, while in patients who underwent a peripheral vascular intervention, ASA plus low-dose rivaroxaban could be considered for the long-term (> 3 months) prevention of MACE and MALE.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40265-022-01756-6.

Trained immunity: adaptation within innate immune mechanisms

The mechanisms underlying innate immune memory have been extensively explored in the last decades but are in fact largely unknown. While the specificity of adaptive immune memory in vertebrates is ensured through the recombination of immunoglobulin family genes and clonal expansion, the basic mechanisms of innate immune cells' non-specific increased responsiveness rely on epigenetic, transcriptional, and metabolic programs after transient stimulation. Changes in these programs result in enhanced responsiveness to secondary challenges with a wide variety of stimuli. This phenomenon is termed 'trained immunity' or 'innate immune memory'. On the one hand, trained immunity improves the response to infections and vaccination, facilitating stronger innate immune responses and enhanced protection against a variety of microbial stimuli. Conversely, trained immunity may contribute to the pathophysiology of cardiovascular, autoinflammatory and neurodegenerative diseases. In this review, we will gather the current body of knowledge in this field and summarize the foundations and mechanisms of trained immunity, the different cell types involved, its consequences for health and disease and the potential of its modulation as a therapeutic tool.

The decylTPP mitochondria-targeting moiety lowers electron transport chain supercomplex levels in primary human skin fibroblasts

Attachment of cargo molecules to lipophilic triphenylphosphonium (TPP⁺) cations is a widely applied strategy for mitochondrial targeting. We previously demonstrated that the vitamin E-derived antioxidant Trolox increases the levels of active mitochondrial complex I (CI), the first complex of the electron transport chain (ETC), in primary human skin fibroblasts (PHSFs) of Leigh Syndrome (LS) patients with isolated CI deficiency. Primed by this finding, we here studied the cellular effects of mitochondria-targeted Trolox (MitoE10), mitochondria-targeted ubiquinone (MitoQ10) and their mitochondria-targeting moiety decylTPP (C₁₀-TPP⁺). Chronic treatment (96 h) with these molecules of PHSFs from a healthy subject and an LS patient with isolated CI deficiency (NDUFS7-V122M mutation) did not greatly affect cell number. Unexpectedly, this treatment reduced CI levels/activity, lowered the amount of ETC supercomplexes, inhibited mitochondrial oxygen consumption, increased extracellular acidification, altered mitochondrial morphology and stimulated hydroethidine oxidation. We conclude that the mitochondria-targeting decylTPP moiety is responsible for the observed effects and advocate that every study employing alkylTPP-mediated mitochondrial targeting should routinely include control experiments with the corresponding alkylTPP moiety.

Establishing the relationship between Familial Dysbetalipoproteinemia and genetic variants in the APOE gene

Familial Dysbetalipoproteinemia (FD) is the second most common monogenic dyslipidemia and is associated with a very high cardiovascular risk due to cholesterol‐enriched remnant lipoproteins. FD is usually caused by a recessively inherited variant in the APOE gene (ε2ε2), but variants with dominant inheritance have also been described. The typical dysbetalipoproteinemia phenotype has a delayed onset and requires a metabolic hit. Therefore, the diagnosis of FD should be made by demonstrating both the genotype and dysbetalipoproteinemia phenotype. Next Generation Sequencing is becoming more widely available and can reveal variants in the APOE gene for which the relation with FD is unknown or uncertain. In this article, two approaches are presented to ascertain the relationship of a new variant in the APOE gene with FD. The comprehensive approach consists of determining the pathogenicity of the variant and its causal relationship with FD by confirming a dysbetalipoproteinemia phenotype, and performing in vitro functional tests and, optionally, in vivo postprandial clearance studies. When this is not feasible, a second, pragmatic approach within reach of clinical practice can be followed for individual patients to make decisions on treatment, follow‐up, and family counseling.

The Hyperintense study: Assessing the effects of induced blood pressure increase and decrease on MRI markers of cerebral small vessel disease: Study rationale and protocol

Background:

Neuroimaging markers of cerebral small vessel disease (SVD) are common in older individuals, but the pathophysiological mechanisms causing these lesions remain poorly understood. Although hypertension is a major risk factor for SVD, the direct causal effects of increased blood pressure are unknown. The Hyperintense study is designed to examine cerebrovascular and structural abnormalities, possibly preceding SVD, in young adults with hypertension. These patients undergo a diagnostic work-up that requires patients to temporarily discontinue their antihypertensive agents, often leading to an increase in blood pressure followed by a decrease once effective medication is restarted. This allows examination of the effects of blood pressure increase and decrease on the cerebral small vessels.

Methods:

Hyperintense is a prospective observational cohort study in 50 hypertensive adults (18–55 years) who will temporarily discontinue antihypertensive medication for diagnostic purposes. MRI and clinical data is collected at four timepoints: before medication withdrawal (baseline), once antihypertensives are largely or completely withdrawn (T = 1), when patients have restarted medication (T = 2) and reached target blood pressure and 1 year later (T = 3). The 3T MRI protocol includes conventional structural sequences and advanced techniques to assess various aspects of microvascular integrity, including blood-brain barrier function using Dynamic Contrast Enhanced MRI, white matter integrity, and microperfusion. Clinical assessments include motor and cognitive examinations and blood sampling.

Discussion:

The Hyperintense study will improve the understanding of the pathophysiological mechanisms following hypertension that may cause SVD. This knowledge can ultimately help to identify new targets for treatment of SVD, aimed at prevention or limiting disease progression.

[Dizziness upon standing: consider autonomic dysfunction]

Many people, particularly elderly, experience dizziness upon standing. It is important to always measure the blood pressure and heart rate in the supine and standing position in these patients. In case of orthostatic hypotension with an insufficient increase in heart rate, one has to consider autonomic dysfunction. Alpha-synucleopathies are frequent causes of autonomic dysfunction, including Parkinson's disease, Pure Autonomic Failure and Multiple System Atrophy. The quality of life can significantly be improved in patients with autonomic dysfunction due to life-style measures (increased salt and water intake, compressive stockings, head-up sleeping) and medication to increase blood pressure (fludrocortisone, midodrine). There is often a considerable delay in the diagnosis of autonomic dysfunction, which prevents adequate treatment. The main message of this paper is that we should all search for orthostatic hypotension in patients with dizziness and, in case of insufficient heart rate increase, refer these patients for autonomic function testing.

Relation Between Plasma Proteomics Analysis and Major Adverse Cardiovascular Events in Patients With Stable Coronary Artery Disease

Objective

Despite the advances in the control of traditional risk factors, coronary artery disease (CAD) remains the greatest cause of morbidity and mortality. Our aim was to establish the relation between plasma proteomics analysis and the risk of cardiovascular events in patients with stable CAD.

Materials and Methods

Patients with stable CAD and documented coronary atherosclerosis were screened for inclusion. Using proximity extension assays, 177 plasma proteins were simultaneously measured. The endpoint consisted of the first major adverse cardiovascular event (MACE) and was the composite of cardiovascular death, acute coronary syndrome, stroke, transient ischemic attack, or acute limb ischemia at 18 months follow-up. Cox proportional-hazards regression with adjustment for multiple comparisons was used to identify biomarkers for the outcomes of interest.

Results

The cohort consisted of 229 patients. Six mediators were associated with MACE (p < 0.001). For these markers, the risk of MACE was calculated: tumor necrosis factor receptor superfamily member 13B (HR = 1.65; 95% CI: 1.30–2.10), C-C motif chemokine-3 (HR = 1.57; 95% CI: 1.23–1.98), decorin (HR = 1.65; 95% CI: 1.26–2.16), fibroblast growth factor-23 (HR = 1.56; 95% CI: 1.23–1.99), tumor necrosis factor-related apoptosis-inducing ligand-receptor 2 (TRAIL-R2) (HR = 1.61; 95% CI: 1.23–2.11), and tumor necrosis factor receptor superfamily member 10A (HR = 1.69; 95% CI: 1.25–2.29). Except for TRAIL-R2, the other proteins were associated with MACE independent of age, sex, diabetes mellitus, or estimated glomerular filtration rate.

Conclusions

In patients with stable CAD, five novel biomarkers were identified as independent risk factors for adverse outcomes. Novel biomarkers could represent pharmacological targets for the prevention of adverse cardiovascular events.

Immune modulatory effects of progesterone on oxLDL-induced trained immunity in monocytes

Atherosclerotic cardiovascular diseases (CVD) are among the leading causes of death in the world. Monocyte‐derived macrophages are key players in the pathophysiology of atherosclerosis. Innate immune memory following exposure of monocytes to atherogenic compounds, such as oxidized low‐density lipoproteins (oxLDL), termed trained immunity, can contribute to atherogenesis. The current study aimed to elucidate intracellular mechanisms of oxLDL‐induced trained immunity. Using untargeted intracellular metabolomics in isolated human primary monocytes, we show that oxLDL‐induced trained immunity results in alterations in the balance of intracellular steroid hormones in monocytes. This was reflected by a decrease in extracellular progesterone concentrations following LPS stimulation. To understand the potential effects of steroid hormones on trained immunity, monocytes were costimulated with oxLDL and the steroid hormones progesterone, hydrocortisone, dexamethasone, β‐estradiol, and dihydrotestosterone. Progesterone showed a unique ability to attenuate the enhanced TNFα and IL‐6 production following oxLDL‐induced trained immunity. Single nucleotide polymorphisms in the nuclear glucocorticoid, progesterone, and mineralocorticoid receptor were shown to correlate with ex vivo oxLDL‐induced trained immunity in 243 healthy volunteers. Pharmacologic inhibition experiments revealed that progesterone exerts the suppression of TNFα in trained immunity via the nuclear glucocorticoid and mineralocorticoid receptors. Our data show that progesterone has a unique ability to suppress oxLDL‐induced trained immunity. We hypothesize that this effect might contribute to the lower incidence of CVD in premenopausal women.

Discovery, diversity, and functional associations of crAss-like phages in human gut metagenomes from four Dutch cohorts

The crAss-like phages are a diverse group of related viruses that includes some of the most abundant viruses of the human gut. To explore their diversity and functional role in human population and clinical cohorts, we analyze gut metagenomic data collected from 1,950 individuals from the Netherlands. We identify 1,556 crAss-like phage genomes, including 125 species-level and 32 genus-level clusters absent from the reference databases used. Analysis of their genomic features shows that closely related crAss-like phages can possess strikingly divergent regions responsible for transcription, presumably acquired through recombination. Prediction of crAss-like phage hosts points primarily to bacteria of the phylum Bacteroidetes, consistent with previous reports. Finally, we explore the temporal stability of crAss-like phages over a 4-year period and identify associations between the abundance of crAss-like phages and several human phenotypes, including depletion of crAss-like phages in inflammatory bowel disease patients.

The role of the mineralocorticoid receptor in immune cells in in cardiovascular disease

Chronic low-grade inflammation and immune cell activation are important mechanisms in the pathophysiology of cardiovascular disease (CVD). Therefore, targeted immunosuppression is a promising novel therapy to lower cardiovascular risk. In this review, we identify the mineralocorticoid receptor (MR) on immune cells as a potential target to modulate inflammation. The MR is present in almost all cells of the cardiovascular system, including immune cells. Activation of the MR in innate and adaptive immune cells induces inflammation which can contribute to CVD, by inducing endothelial dysfunction and hypertension. Moreover, it accelerates atherosclerotic plaque formation and destabilization and impairs tissue regeneration after ischemic events. Identifying the molecular targets for these non-renal actions of the MR provide promising novel cardiovascular drug targets for mineralocorticoid receptor antagonists (MRAs), which are currently mainly applied in hypertension and heart failure.

Characterization of gut microbial structural variations as determinants of human bile acid metabolism

Bile acids (BAs) facilitate intestinal fat absorption and act as important signaling molecules in host-gut microbiota crosstalk. BA-metabolizing pathways in the microbial community have been identified, but it remains largely unknown how the highly variable genomes of gut bacteria interact with host BA metabolism. We characterized 8,282 structural variants (SVs) of 55 bacterial species in the gut microbiomes of 1,437 individuals from two cohorts and performed a systematic association study with 39 plasma BA parameters. Both variations in SV-based continuous genetic makeup and discrete clusters showed correlations with BA metabolism. Metagenome-wide association analysis identified 809 replicable associations between bacterial SVs and BAs and SV regulators that mediate the effects of lifestyle factors on BA metabolism. This is the largest microbial genetic association analysis to demonstrate the impact of bacterial SVs on human BA composition, and it highlights the potential of targeting gut microbiota to regulate BA metabolism through lifestyle intervention.

An integrative genomics approach identifies KDM4 as a modulator of trained immunity

Innate immune cells are able to build memory characteristics via a process termed “trained immunity.” Host factors that influence the magnitude of the individual trained immunity response remain largely unknown. Using an integrative genomics approach, our study aimed to prioritize and understand the role of specific genes in trained immunity responses. In vitro‐induced trained immunity responses were assessed in two independent population‐based cohorts of healthy individuals, the 300 Bacillus Calmette‐Guérin (300BCG; n = 267) and 200 Functional Genomics (200FG; n = 110) cohorts from the Human Functional Genomics Project. Genetic loci that influence cytokine responses upon trained immunity were identified by conducting a meta‐analysis of QTLs identified in the 300BCG and 200FG cohorts. From the identified QTL loci, we functionally validated the role of PI3K‐Akt signaling pathway and two genes that belong to the family of Siglec receptors (Siglec‐5 and Siglec‐14). Furthermore, we identified the H3K9 histone demethylases of the KDM4 family as major regulators of trained immunity responses. These data pinpoint an important role of metabolic and epigenetic processes in the regulation of trained immunity responses, and these findings may open new avenues for vaccine design and therapeutic interventions.

Cerebrotendinous xanthomatosis without neurological involvement

BACKGROUND

Cerebrotendinous xanthomatosis (CTX) is an autosomal recessively inherited inborn error of metabolism. Neurological symptoms are considered to be a clinical hallmark of untreated adult patients. We describe a 'milder CTX phenotype', without neurological involvement.

METHODS

We performed a retrospective patient file study in 79 genetically confirmed Dutch patients with CTX (55 patients aged ≥ 21 years) to study the clinical heterogeneity of CTX. We studied the frequency of adult patients with CTX without neurological involvement at diagnosis, in our Dutch cohort, and included a family from South Africa and patients from Italy, USA, Chile and Asia from the literature.

RESULTS

In total, we describe 19 adult patients with CTX from 16 independent families, without neurological symptoms at diagnosis. A relatively small percentage (21%, n = 4) had a history of cataract. The majority, 84% (n = 16), presented with tendon xanthomas as the sole or predominant feature. The majority of patients showed increased plasma cholesterol levels. No correlation was found between this 'milder phenotype', the cholestanol levels and the CYP27A1 genotype. In addition, we describe three novel mutations in the CYP27A1 gene.

CONCLUSIONS

This study shows the clinical heterogeneity of CTX, highlighting the existence of a 'milder phenotype', that is without neurological involvement at diagnosis. Adult patients with CTX may present with tendon xanthomas as the sole or predominant feature, mimicking familial hypercholesterolemia. It is important to realize that the absence of neurological symptoms does not rule out the development of future neurological symptoms. As CTX is a treatable disorder, early diagnosis and initiation of treatment when additional clinical signs occur is therefore essential.

[Immune cell activation in cardiovascular disease: new pathophysiological mechanisms explained]

Optimal treatment of classical risk factors, such as dyslipidemia, cannot completely prevent atherosclerotic cardiovascular disease, which is called residual cardiovascular risk. The anti-inflammatory drugs colchicine and canakinumab can lower this residual risk, illustrating the importance of inflammation in the pathophysiology of cardiovascular disease. Circulating granulocytes and activated monocytes are associated with atherosclerotic cardiovascular disease in observational studies. In the past few years, two mechanisms have been discovered that contribute to monocyte and neutrophil activation in the context of atherosclerosis, namely trained immunity and clonal hematopoiesis. In this Perspective, we discuss these mechanisms, since we foresee that in the near future knowledge of these mechanisms could improve cardiovascular risk prediction and provide targets for novel drugs to prevent or treat cardiovascular diseases.

Functional and transcriptional differences in monocytes from children with obesity compared to children of healthy weight

Background and aim

Cardiometabolic risk accrues across the entire life course and childhood is a key epoch for effective prevention. Obesity in childhood is the most prevalent modifiable risk factor for later cardiovascular disease (CVD). Inflammatory biomarkers and innate immune capacity are increased in adults with obesity, but childhood data are scarce. We aimed to investigate (i) innate immune cell activation in children with and without obesity; and (ii) whether weight loss impacts the innate immune inflammatory phenotype.

Methods

The innate immune phenotype of Peripheral Blood Mononuclear Cells (PBMCs) from 31 children with obesity (BMI z-score&gt;2.5) and 22 children of healthy weight (−1.5≤BMIz≤1.5, sex, age and pubertal stage matched) was characterized by high dimensional flow cytometry, ex vivo stimulation assays with subsequent 27-plex cytokine measurements, and transcriptome analysis using RNA sequencing (Figure 1). Children with obesity participated to the Royal Children's Hospital Weight Management Service (median 5 years) and at follow-up, PBMCs were obtained again as well as anthropometric data and subclinical cardiovascular phenotypes.

Results

Flow cytometric analysis showed marked differences in cell composition between children with obesity and children of healthy weight. Specifically, children with obesity have significant changes in monocyte subsets and an increased expression of monocyte activation markers. Upon stimulation, monocytes of children with obesity show an increased cytokine production capacity. Finally, transcriptomic analysis shows significant differences between monocytes from obese children and healthy controls. Effects of weight loss on these immune parameters and correlations with preclinical CVD phenotypes are currently being analysed.

Conclusions

Monocytes from children with obesity have a pro-inflammatory phenotype compared to children of normal weight. Heightened inflammation may contribute to increased CVD risk later in life and may offer opportunities for early intervention.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Dutch Scientific Organisation (NWO) - Rubicon grant to S.B. Dutch Heart Foundation - CVON IN CONTROL II to N.P.R. and D.B. Figure 1. Schematical overview of study

Adipose tissue induces trained innate immunity in patients with obesity

Introduction

Obesity is the most prevalent modifiable risk factor for atherosclerotic cardiovascular disease and is characterized as a chronic inflammatory disease. Cells of the innate immune system, especially monocytes and macrophages, play a pivotal role in the various stages of atherosclerosis, although it still remains elusive why the strong inflammatory response persists in time. We recently showed that cells of the innate immune system, such as monocytes, can adopt a long-term immunological memory. Upon brief stimulation with atherogenic stimuli, monocytes demonstrate an enhanced long-term pro-inflammatory and pro-atherogenic phenotype. This is termed trained immunity and is mediated via epigenetic and metabolic reprogramming. The clinical relevance of these findings was verified in patients with symptomatic atherosclerosis, in which circulating monocytes showed a trained immune phenotype.

Purpose

As various adipose tissue-related particles, including pro-inflammatory cytokines and fatty acids, are capable of inducing trained immunity in vitro, we hypothesized that adipose tissue from obese subjects might induce training in peripheral monocytes, thereby contributing to the increased risk of atherosclerotic CVD in these patients. In line with this hypothesis, it is unclear whether chronic inflammation sustains after a previous period of obesity despite significant weight loss.

Methods

We obtained blood from 25 patients with obesity before and 6 months after bariatric surgery. Monocyte subsets and activation phenotype were studied using flow cytometry. Cytokine production capacity of isolated PBMCs was studied after ex vivo stimulation with several infectious and metabolic stimuli and we characterized isolated monocytes using transcriptomics. Next, we obtained visceral (VAT) and subcutaneous adipose tissue (SAT) biopsies from 10 patients. Using our established in vitro model for trained immunity, we co-incubated healthy human monocytes with the adipose tissue biopsies for 24 hours in a trans-well set-up. After 24 hours, the adipose tissue was removed and monocytes were rested. On day 6, the cells were re-stimulated for 24 hours with a second stimulus and cytokine production and the transcriptome of the macrophages was analyzed.

Results

Both SAT and VAT obtained from patients with obesity can induce a long-term memory in healthy human monocytes, as demonstrated by an increased cytokine production capacity 6 days after co-incubation. Interestingly, VAT induced a higher cytokine response compared to SAT. Analysis of the inflammatory phenotype of peripheral cells before and after bariatric surgery is currently ongoing.

Conclusions

Adipose tissue-secreted metabolites, particularly secreted by VAT, have the potential to induce persistent innate immune cell activation. Our further analyses will show whether the secretion of these molecules and the activation of the innate immune system persists upon weight loss.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation

Hyperglycemia Induces Trained Immunity in Macrophages and Their Precursors and Promotes Atherosclerosis

BACKGROUND

Cardiovascular risk in diabetes remains elevated despite glucose-lowering therapies. We hypothesized that hyperglycemia induces trained immunity in macrophages, promoting persistent proatherogenic characteristics.

METHODS

Bone marrow-derived macrophages from control mice and mice with diabetes were grown in physiological glucose (5 mmol/L) and subjected to RNA sequencing (n=6), assay for transposase accessible chromatin sequencing (n=6), and chromatin immunoprecipitation sequencing (n=6) for determination of hyperglycemia-induced trained immunity. Bone marrow transplantation from mice with (n=9) or without (n=6) diabetes into (normoglycemic) Ldlr-/- mice was used to assess its functional significance in vivo. Evidence of hyperglycemia-induced trained immunity was sought in human peripheral blood mononuclear cells from patients with diabetes (n=8) compared with control subjects (n=16) and in human atherosclerotic plaque macrophages excised by laser capture microdissection.

RESULTS

In macrophages, high extracellular glucose promoted proinflammatory gene expression and proatherogenic functional characteristics through glycolysis-dependent mechanisms. Bone marrow-derived macrophages from diabetic mice retained these characteristics, even when cultured in physiological glucose, indicating hyperglycemia-induced trained immunity. Bone marrow transplantation from diabetic mice into (normoglycemic) Ldlr-/- mice increased aortic root atherosclerosis, confirming a disease-relevant and persistent form of trained innate immunity. Integrated assay for transposase accessible chromatin, chromatin immunoprecipitation, and RNA sequencing analyses of hematopoietic stem cells and bone marrow-derived macrophages revealed a proinflammatory priming effect in diabetes. The pattern of open chromatin implicated transcription factor Runt-related transcription factor 1 (Runx1). Similarly, transcriptomes of atherosclerotic plaque macrophages and peripheral leukocytes in patients with type 2 diabetes were enriched for Runx1 targets, consistent with a potential role in human disease. Pharmacological inhibition of Runx1 in vitro inhibited the trained phenotype.

CONCLUSIONS

Hyperglycemia-induced trained immunity may explain why targeting elevated glucose is ineffective in reducing macrovascular risk in diabetes and suggests new targets for disease prevention and therapy.

An Explorative Study on Monocyte Reprogramming in the Context of Periodontitis In Vitro and In Vivo

Aims

Periodontitis is an independent risk factor for cardiovascular disease, but the mechanistic link is not fully understood. In atherosclerotic cardiovascular disease, monocytes can adopt a persistent hyperresponsive phenotype, termed trained immunity. We hypothesized that periodontitis-associated bacteria can induce trained immunity in monocytes, which subsequently accelerate atherosclerosis development.

Materials and Methods

We combined in vitro experiments on human primary monocytes and in vivo techniques in patients with periodontitis to test this hypothesis. Adherent peripheral blood mononuclear cells (PBMCs) were transiently exposed in vitro to Porphyromonas gingivalis for 24 hours, and restimulated with lipopolysaccharide (LPS) or Pam3CysK4 (P3C) six days later, to measure interleukin-6 (IL-6) and tumor necrosis factor α (TNFα) production. In an exploratory observational study, patients with severe periodontitis (63 ± 6 years, n=14) and control subjects with no-to-mild periodontitis (54 ± 10 years, n=14) underwent venipuncture and 2’-deoxy-2’-[¹⁸F]fluoro-D-glucose positron-emission-tomography ([¹⁸F]FDG PET/CT) scanning.

Results

When adherent peripheral blood mononuclear cells (PBMCs) were transiently exposed in vitro to Porphyromonas gingivalis for 24 hours, and restimulated with LPS or P3C six days later, IL-6 and TNFα production was significantly increased (TNFα/P3C, p<0.01). Circulating leukocytes, IL-6 and interleukin-1 receptor antagonist (IL-1Ra) concentrations were generally higher in patients compared to controls (leukocytes: p<0.01; IL-6: p=0.08; IL-1Ra: p=0.10). Cytokine production capacity in PBMCs after 24h stimulation revealed no differences between groups. [¹⁸F]FDG PET/CT imaging showed a trend for increased [¹⁸F]FDG-uptake in the periodontium [mean standard uptake value (SUV_mean), p=0.11] and in femur bone marrow (SUV_mean, p=0.06), but no differences were observed for vascular inflammation. Positive correlations between severity of periodontitis, measured by The Dutch Periodontal Screening Index and pocket depth, with circulating inflammatory markers and tissue inflammation were found.

Conclusions

P. gingivalis induces long-term activation of human monocytes in vitro (trained immunity). Patients with severe periodontitis did have signs of increased systemic inflammation and hematopoietic tissue activation. However, their circulating monocytes did not show a hyperresponsive phenotype. Together we suggest that trained immunity might contribute to local periodontal inflammation which warrants further investigation.

Clonal hematopoiesis is associated with low CD4 nadir and increased residual HIV transcriptional activity in virally suppressed individuals with HIV

Clonal hematopoiesis, a common age-related phenomenon marked by expansion of cells with clonal hematopoiesis driver mutations, has been associated with all-cause mortality, cancer, and cardiovascular disease. People with HIV (PWH) are at risk for non-AIDS–related comorbidities such as atherosclerotic cardiovascular disease and cancer. In a cross-sectional cohort study, we compared clonal hematopoiesis prevalence in PWH on stable antiretroviral therapy with prevalence in a cohort of overweight individuals and a cohort of age- and sex-matched population controls. The prevalence of clonal hematopoiesis adjusted for age was increased and clone size was larger in PWH compared to population controls. Clonal hematopoiesis is associated with low CD4 nadir, increased residual HIV-1 transcriptional activity, and coagulation factors in PWH. Future studies on the effect of clonal hematopoiesis on the HIV reservoir and non-AIDS–related comorbidities are warranted.