Inflammatory biomarkers in ischemic heart disease

Ischemic heart disease (IHD) is a major cause of death in the western world. Although the age-standardized mortality rates are decreasing, the burden of the disease remains high and novel therapeutic strategies are still needed to improve clinical outcome. In the past decades, inflammation has been recognized as an important factor throughout all stages of IHD. The increase in understanding the inflammatory mechanisms has uncovered an intriguing diversity of potentially targetable pathways. However, the exact role of inflammation still remains to be further elucidated. This thesis supports the hypothesis that inflammation plays an important role across all stages of IHD, varying from atherosclerosis to myocardial infarction, and eventually ischemic heart failure. Increased inflammation is associated with a decrease in cardiac function after myocardial infarction, but adequate anti-inflammatory therapies that may aid in reducing this decline remain to be developed or to be proven to be effective. It is therefore essential to further unravel the complex pathophysiological inflammatory mechanisms underlying IHD. New techniques such as single cell RNA sequencing, can help us to further study these complex mechanisms. Furthermore, accumulating evidence has suggested that the human gut microbiome may play an important role in the pathophysiology of IHD through the modulation of inflammation related to the event. Although the interplay of inflammation and the human gut microbiome in IHD is a relatively young field of research, a better understanding of these two may aid in the improvement of risk stratification, therapeutic treatment efficacy, and prognosis of IHD

Comparison of domains of self-reported physical activity between Kenyan adult urban-slum dwellers and national estimates

Background: Non-communicable diseases (NCDs) - largely the result of modifiable behavioral risks such as physical inactivity that gradually develop into physiological risks - are a main cause of morbidity and mortality worldwide. In Kenya, a nationally representative STEPwise survey of risk factors for NCDs established that 10.8% of Kenyans accumulated low levels of total physical activity. Objectives: The goal of our analyses was to compare domains of self-reported physical activity in two Nairobi slums to national estimates. Methods: Levels and time of self-reported activity in three domains (work, transport, and recreation), collected as part of a SCALE-UP study conducted in Korogocho and Viwandani slums in Nairobi, were compared to STEPwise findings. Results: The samples included a total of 10,128 participants (5,628 slum, 4,500 national). Only 7.1% and 4.0% of slum dwellers reported low levels of work and transport physical activity, respectively, but 95.9% reported low levels of recreation-related activity. Slum residents reported higher mean daily minutes of total activity than the national estimate (499 minutes versus 291 minutes), however, both samples spent similar proportions of total activity on work (79.0% slum, 78.3% national), transport (20.4% slum, 18.1% national), and recreation (0.6% slum, 3.6% national) activities. Conclusions: While the total amount of time spent in different domains of self-reported activity differs between urban slum residents and the national Kenyan population, proportions of time in each of the three domains are similar. It is important that such differences or similarities be considered when addressing NCD risk factors in these populations

Sex differences in leukocyte profile in ST-elevation myocardial infarction patients

BACKGROUND: Whether sex differences exist in the inflammatory response after ST-elevation myocardial infarction (STEMI) remains to be elucidated. We studied leukocyte profiles and their prognostic value in men and women presenting with STEMI. METHODS: From a total of 552 consecutive STEMI patients, blood samples were collected at hospital admission. Linear regression was used to assess the relationship between leukocyte profiles and enzymatic infarct size. Cox regression was used to assess the association between leukocyte profiles and one-year mortality. RESULTS: Women presented with higher lymphocyte counts (2.3·109 cells/L (IQR 1.6-3.1) vs. 1.8·109 cells/L (IQR 1.4-2.5), p = 3.00 ∙ 10-4) and percentages (21.1% (IQR 14.4-28.1) vs. 17.1% (IQR 12.3-24.3), p = 0.004). Lymphocyte to monocyte ratio (LMR) was also higher in women (3.25 (IQR 2.56-4.5) vs. 2.68 (IQR 2.08-3.59), p = 7.28 ∙ 10-7). Higher LMR was associated with lower peak CK-MB (β = -0.27 (95% CI: -0.50, -0.03), p = 0.026), lower peak troponin T (β = -0.45 (95% CI: -0.77, -0.13), p = 0.006) and lower one-year mortality risk (HR 0.35 (95% CI: 0.13, 0.96), p = 0.042). CONCLUSION: At admission for STEMI, women present with higher lymphocyte count and LMR. Higher LMR is associated with smaller infarct size and decreased one-year mortality risk and could be used as a biomarker to predict outcome

Genetically Determined ABO Blood Group and its Associations With Health and Disease

Objective: To determine the spectrum of phenotypes linked to the ABO blood group system, using genetic determinants of the ABO blood group system. Approach and Results: We assessed the risk of 41 health and disease outcomes, and 36 linear traits associated with the ABO blood group system in the UK Biobank cohort. A total of 406 755 unrelated individuals were included in this study. Blood groups A, B, and O were determined based on allele combinations of previously established single-nucleotide polymorphisms rs8176746, rs8176719 in the ABO gene. Group AB was excluded because of its relative small sample size. Overall, 187 387 (46%) were male with a mean (SD) age of 57±8.1 years and a median total exposure of 64 person-years (interquartile range, 57-70). Of 406 755 individuals, 182 621 (44.9%) participants had blood group O, 182 786 (44.9%) had blood group A, and 41 348 (10.2%) had blood group B. ABO blood groups were associated with 11 health and disease outcomes (P<2.19×10-4). ABO blood groups were primarily associated with cardiovascular outcomes. Compared with individuals with blood group O, blood groups A and B were associated with increased odds of up to 1.56 (95% CI, 1.43-1.69) for thromboembolic events and decreased odds for hypertension (0.94 [95% CI, 0.92-0.97]). Conclusions: The ABO blood group system is associated with several parameters of healthy aging and disease development. Knowledge of ABO blood groups might be of interest for more personalized approaches towards health maintenance and the prevention of diseases

Human genetic determinants of the gut microbiome and their associations with health and disease:a phenome-wide association study

Small-scale studies have suggested a link between the human gut microbiome and highly prevalent diseases. However, the extent to which the human gut microbiome can be considered a determinant of disease and healthy aging remains unknown. We aimed to determine the spectrum of diseases that are linked to the human gut microbiome through the utilization of its genetic determinants as a proxy for its composition. 180 single nucleotide polymorphisms (SNPs) known to influence the human gut microbiome were used to assess the association with health and disease outcomes in 422,417 UK Biobank participants. Potential causal estimates were obtained using a Mendelian randomization (MR) approach. From the total sample analysed (mean age was 57 ± 8 years), 194,567 (46%) subjects were male. Median exposure was 66-person years (interquartile range 59–72). Eleven SNPs were significantly associated with 28 outcomes (Bonferroni corrected P value < 4.63·10−6) including food intake, hypertension, atopy, COPD, BMI, and lipids. Multiple SNP MR pointed to a possible causal link between Ruminococcus flavefaciens and hypertension, and Clostridium and platelet count. Microbiota and their metabolites might be of importance in the interplay between overlapping pathophysiological processes, although challenges remain in establishing causal relationships

Translational insights from single-cell technologies across the cardiovascular disease continuum

Cardiovascular disease is the leading cause of death worldwide. The societal health burden it represents can be reduced by taking preventive measures and developing more effective therapies. Reaching these goals, however, requires a better understanding of the pathophysiological processes leading to and occurring in the diseased heart. In the last 5 years, several biological advances applying single-cell technologies have enabled researchers to study cardiovascular diseases with unprecedented resolution. This has produced many new insights into how specific cell types change their gene expression level, activation status and potential cellular interactions with the development of cardiovascular disease, but a comprehensive overview of the clinical implications of these findings is lacking. In this review, we summarize and discuss these recent advances and the promise of single-cell technologies from a translational perspective across the cardiovascular disease continuum, covering both animal and human studies, and explore the future directions of the field

Temporal course of plasma trimethylamine n-oxide (Tmao) levels in st-elevation myocardial infarction

The gut metabolite trimethylamine N-oxide (TMAO) at admission has a prognostic value in ST-elevation myocardial infarction (STEMI) patients. However, its sequential changes and relationship with long-term infarct-related outcomes after primary percutaneous coronary intervention (PCI) remain elusive. We delineated the temporal course of TMAO and its relationship with infarct size and left ventricular ejection fraction (LVEF) post-PCI, adjusting for the estimated glomerular filtration rate (eGFR). We measured TMAO levels at admission, 24 h and 4 months post-PCI in 379 STEMI patients. Infarct size and LVEF were determined by cardiac magnetic resonance 4 months after PCI. TMAO levels decreased from admission (4.13 ± 4.37 μM) to 24 h (3.41 ± 5.84 μM, p = 0.001) and increased from 24 h to 4 months (3.70 ± 3.86 μM, p = 0.026). Higher TMAO values at 24 h were correlated to smaller infarct sizes (rho = −0.16, p = 0.024). Larger declines between admission and 4 months suggestively correlated with smaller infarct size, and larger TMAO increases between 24 h and 4 months were associated with larger infarct size (rho = −0.19, p = 0.008 and rho = −0.18, p = 0.019, respectively). Upon eGFR stratification using 90 mL/min/1.73 m(2) as a cut-off, significant associations between TMAO and infarct size were only noted in subjects with impaired renal function. In conclusion, TMAO levels in post-PCI STEMI patients are prone to fluctuations, and these fluctuations could be prognostic for infarct size, particularly in patients with impaired renal function

Search for a Functional Genetic Variant Mimicking the Effect of SGLT2 Inhibitor Treatment

SGLT2 inhibitors (SGLT2i) block renal glucose reabsorption. Due to the unexpected beneficial observations in type 2 diabetic patients potentially related to increased natriuresis, SGLT2i are also studied for heart failure treatment. This study aimed to identify genetic variants mimicking SGLT2i to further our understanding of the potential underlying biological mechanisms. Using the UK Biobank resource, we identified 264 SNPs located in the SLC5A2 gene or within 25kb of the 5′ and 3′ flanking regions, of which 91 had minor allele frequencies >1%. Twenty-seven SNPs were associated with glycated hemoglobin (HbA1c) after Bonferroni correction in participants without diabetes, while none of the SNPs were associated with sodium excretion. We investigated whether these variants had a directionally consistent effect on sodium excretion, HbA1c levels, and SLC5A2 expression. None of the variants met these criteria. Likewise, we identified no common missense variants, and although four SNPs could be defined as 5′ or 3′ prime untranslated region variants of which rs45612043 was predicted to be deleterious, these SNPs were not annotated to SLC5A2. In conclusion, no genetic variant was found mimicking SGLT2i based on their location near SLC5A2 and their association with sodium excretion or HbA1c and SLC5A2 expression or function