Lipids and vascular disease: a framingham perspective

Lipid Disorders Management Strategies (2024) in Prediabetic and Diabetic Patients

Dyslipidaemia is a modifiable risk factor commonly associated with diabetes mellitus and prediabetes, with a major impact on the early development of atherosclerotic cardiovascular disease. Various studies have tried to identify the key treatment targets, their optimal values according to patients' CV risk, and the most efficient yet safe therapeutic agents which, alongside lifestyle changes, would improve lipid levels and reduce cardiovascular mortality and morbidity. Currently, there are multiple pharmacologic options that can be used in the management of dyslipidaemia, such as statins, ezetimibe, bempedoic acid, PCSK9 inhibitors, n-3 polyunsaturated fatty acids or fibrates, to name only a few, while many other are under development. In the current setting of a continuously increasing population of patients with metabolic disorders, this review aims to summarise current knowledge regarding lipid disorders and the recommendations of recent guidelines in treating dyslipidaemia in patients with diabetes mellitus or prediabetes.

Systematic elucidation of genetic mechanisms underlying cholesterol uptake

Genetic variation contributes greatly to LDL cholesterol (LDL-C) levels and coronary artery disease risk. By combining analysis of rare coding variants from the UK Biobank and genome-scale CRISPR-Cas9 knockout and activation screening, we substantially improve the identification of genes whose disruption alters serum LDL-C levels. We identify 21 genes in which rare coding variants significantly alter LDL-C levels at least partially through altered LDL-C uptake. We use co-essentiality-based gene module analysis to show that dysfunction of the RAB10 vesicle transport pathway leads to hypercholesterolemia in humans and mice by impairing surface LDL receptor levels. Further, we demonstrate that loss of function of OTX2 leads to robust reduction in serum LDL-C levels in mice and humans by increasing cellular LDL-C uptake. Altogether, we present an integrated approach that improves our understanding of the genetic regulators of LDL-C levels and provides a roadmap for further efforts to dissect complex human disease genetics.

Systematic elucidation of genetic mechanisms underlying cholesterol uptake

Genetic variation contributes greatly to LDL cholesterol (LDL-C) levels and coronary artery disease risk. By combining analysis of rare coding variants from the UK Biobank and genome-scale CRISPR-Cas9 knockout and activation screening, we have substantially improved the identification of genes whose disruption alters serum LDL-C levels. We identify 21 genes in which rare coding variants significantly alter LDL-C levels at least partially through altered LDL-C uptake. We use co-essentiality-based gene module analysis to show that dysfunction of the RAB10 vesicle transport pathway leads to hypercholesterolemia in humans and mice by impairing surface LDL receptor levels. Further, we demonstrate that loss of function of OTX2 leads to robust reduction in serum LDL-C levels in mice and humans by increasing cellular LDL-C uptake. Altogether, we present an integrated approach that improves our understanding of genetic regulators of LDL-C levels and provides a roadmap for further efforts to dissect complex human disease genetics.

Risk Factors for Premature Myocardial Infarction: A Systematic Review and Meta-analysis of 77 Studies

Objective

To evaluate the magnitude of the association between risk factors and premature myocardial infarction (MI) (men aged 18-55 years; women aged 18-65 years).

Patients and Methods

We searched MEDLINE and other databases from inception through April 30, 2020, as well as bibliography of articles selected for data extraction. We selected observational studies reporting the magnitude of the association of at least 1 risk factor (demographic characteristics, lifestyle factors, clinical risk factors, or biomarkers) with premature MI and a control group. Pooled risk estimates (random effects) from all studies unadjusted and adjusted for risk factors were reported as summary odds ratios (ORs) with 95% CIs.

Results

From 35,320 articles of 12.7 million participants, we extracted data on 19 risk factors from 77 studies across 58 countries. Men had a higher risk of premature MI (OR, 2.39; 95% CI, 1.71 to 3.35) than did women. Family history of cardiac disease was associated with a higher risk of premature MI (OR, 2.67; 95% CI, 2.29 to 3.27). Major modifiable risk factors associated with higher risk were current smoking (OR, 4.34; 95% CI, 3.68 to 5.12 vs no/former), diabetes mellitus (OR, 3.54; 95% CI, 2.69 to 4.65), dyslipidemia (OR, 2.94; 95% CI, 1.76 to 4.91), and hypertension (OR, 2.85; 95% CI, 2.48 to 3.27). Higher body mass index carried higher risk (OR, 1.46; 95% CI, 1.24 to 1.71 for ≥25 kg/m² vs <25 kg/m²). Biomarkers associated with 2- to 3-fold higher risk were total cholesterol levels greater than 200 mg/dL, triglyceride levels higher than 150 mg/dL, and high-density lipoprotein cholesterol levels less than 60 mg/dL (to convert to mmol/L, multiply by 0.0259).

Conclusion

Major risk factors for premature MI are mostly amenable to patient, population, and policy level interventions. Mild elevations in body mass index and triglyceride levels were associated with higher risk, which has implications for the growing worldwide epidemic of cardiometabolic diseases.

Most important advances in preventive cardiology during this past decade: Viewpoint from the American Society for Preventive Cardiology

The rapidly expanding field of preventive cardiology has brought with it several major advances in the past decade. Changes in guidelines for cholesterol mangement focusing on the identification of "statin eligible groups" and removal of actual low-density lipoprotein cholesterol (LDL-C) targets, in particular, as well as lower targets for blood pressure in updated hypertension guidelines, have made a major impact on healthcare. The availability of the sodium glucose transport protein-2 (SGLT2) inhibitors and glucagon-like peptide -1 receptor antagonists (GLP1-RA) for managing diabetes have shifted our focus in diabetes care beyond glucose lowering to addressing cardiovascular risk reduction. While many prior trials of fish oil therapy have failed to show benefit, the recent Reduction of Cardiovascular Events With EPA - Intervention Trial (REDUCE-IT) testing the efficacy of icosapent ethyl has shown dramatic benefit in further addressing residual atherosclerotic cardiovascular disease (ASCVD) risk beyond statin therapy not only in those with known ASCVD, but also in diabetic patients with multiple risk factors. The past decade also ushered in confirmation of the inflammation hypothesis of atherosclerosis with the Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS) using canakinumab, despite the fact the therapy was not approved by the Food and Drug Administration (FDA) for cardiovascular risk reduction. Also, to improve our understanding of heart disease in women, the emergence of novel concepts of ischemia or myocardial infarction in those with normal or nonobstructive atherosclerotic disease has been a major advance. Moreover, the past decade brought the emergence of proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibody therapy and the cardiovascular risk reduction benefits seen in the Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk (FOURIER) and Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab (ODYSSEY OUTCOMES) trials, providing further evidence-based therapy for additional reduction of ASCVD risk beyond statin therapy. The PCSK9 monoclonal antibodies have facilitated the attainment of LDL-C levels never previously thought possible. Finally with the mRNA interference therapy inclisiran in development, we may soon have a "vaccine-like" approach for addressing dyslipidemia and atherosclerosis.

Estimating the Impact of Novel Digital Therapeutics in Type 2 Diabetes and Hypertension: Health Economic Analysis

BACKGROUND

Behavioral interventions can meaningfully improve cardiometabolic conditions. Digital therapeutics (DTxs) delivering these interventions may provide benefits comparable to pharmacologic therapies, displacing medications for some patients.

OBJECTIVE

Our objective was to estimate the economic impact of a digital behavioral intervention in type 2 diabetes mellitus (T2DM) and hypertension (HTN) and estimate the impact of clinical inertia on deprescribing medications.

METHODS

Decision analytic models estimated health resource savings and cost effectiveness from a US commercial payer perspective. A 3-year time horizon was most relevant to the intervention and payer. Effectiveness of the DTx in improving clinical outcomes was based on cohort studies and published literature. Health resource utilization (HRU), health state utilities, and costs were drawn from the literature with costs adjusted to 2018 dollars. Future costs and quality-adjusted life years (QALYs) were discounted at 3%. Sensitivity analyses assessed uncertainty.

RESULTS

Average HRU savings ranged from $97 to $145 per patient per month, with higher potential benefits in T2DM. Cost-effectiveness acceptability analyses using a willingness-to-pay of $50,000/QALY indicated that the intervention would be cost effective at total 3-year program costs of $6468 and $6620 for T2DM and HTN, respectively. Sensitivity analyses showed that reduced medication costs are a primary driver of potential HRU savings, and the results were robust within values tested. A resistance to deprescribe medications when a patient's clinical outcomes improve can substantially reduce the estimated economic benefits. Our models rely on estimates of clinical effectiveness drawn from limited cohort studies with DTxs and cannot account for other disease management programs that may be implemented. Performance of DTxs in real-world settings is required to further validate their economic benefits.

CONCLUSIONS

The DTxs studied may provide substantial cost savings, in part by reducing the use of conventional medications. Clinical inertia may limit the full cost savings of DTxs.

Association of complete blood count parameters, d-dimer, and soluble P-selectin with risk of arterial thromboembolism in patients with cancer

BACKGROUND

Patients with cancer are at risk of developing arterial thromboembolism (ATE). With the prevalence of cancer and cardiovascular diseases on the rise, the identification of risk factors for ATE in patients with cancer is of emerging importance.

OBJECTIVES

As data on the association of potential biomarkers with risk of ATE in patients with cancer are scarce, we conducted a cohort study with the aim to identify blood-based biomarkers for ATE risk prediction in patients with cancer.

PATIENTS/METHODS

Overall, 1883 patients with newly diagnosed cancer or progressive disease after complete or partial remission were included and followed for 2 years. Venous blood was drawn at study inclusion for measurement of complete blood count parameters, total cholesterol, d-dimer, and soluble P-selectin (sP-selectin) levels.

RESULTS

The 2-year cumulative incidence of ATE was 2.5%. In univariable analysis, red cell distribution width (subdistribution hazard ratio (SHR) per doubling: 4.4, 95% CI: 1.4-14.1), leukocyte count (1.2, 1.1-1.5), neutrophil count (1.6, 1.1-2.3), and sP-selectin levels (1.9, 1.3-2.7) were associated with risk of ATE in patients with cancer; d-dimer was not associated with the risk of ATE (1.1, 0.9-1.4). After adjustment for age, sex, and smoking status the association prevailed for the neutrophil count (adjusted [adj.] SHR per doubling: 1.6, 1.1-2.4), and sP-selectin levels (1.8, 1.2-2.8).

CONCLUSIONS

An elevated absolute neutrophil count and higher sP-selectin levels were associated with an increased risk of ATE in patients with cancer. Their role for predicting cancer-related ATE needs to be validated in further studies.

Trajectories of Blood Lipid Concentrations Over the Adult Life Course and Risk of Cardiovascular Disease and All-Cause Mortality: Observations From the Framingham Study Over 35 Years

Background

Elevated total cholesterol (TC), low‐density lipoprotein cholesterol (LDL‐C), triglycerides, and non‐high‐density lipoprotein cholesterol (non‐HDL‐C) and low high‐density lipoprotein cholesterol (HDL‐C) concentrations correlate with atherosclerotic cardiovascular disease (ASCVD) and mortality. Therefore, understanding how lipid trajectories throughout adulthood impact ASCVD and mortality risk is essential.

Methods and Results

We investigated 3875 Framingham Offspring participants (54% women, mean age 48 years) attending ≥1 examination between 1979 and 2014. We evaluated longitudinal correlates of each lipid subtype using mixed‐effects models. Next, we clustered individuals into trajectories through group‐based modeling. Thereafter, we assessed the prospective association of lipid trajectories with ASCVD and mortality. Male sex, greater body mass index, and smoking correlated with higher TC, LDL‐C, triglycerides, non‐HDL‐C, and lower HDL‐C concentrations. We identified 5 TC, HDL‐C, and LDL‐C trajectories, and 4 triglycerides and non‐HDL‐C trajectories. Upon follow‐up (median 8.2 years; 199 ASCVD events; 256 deaths), elevated TC (>240 mg/dL), LDL‐C (>155 mg/dL), or non‐HDL‐C (>180 mg/dL) concentrations conferred >2.25‐fold ASCVD and mortality risk compared with concentrations <165 mg/dL, <90 mg/dL, and <115 mg/dL, respectively ([TC hazard ratio (HR)_ASCVD=4.17, 95% CI 1.94–8.99; TC HR_death=2.47, 95% CI 1.28–4.76] [LDL‐C HR_ASCVD=5.09, 95% CI 1.54–16.85; LDL‐C HR_death=4.04, 95% CI 1.84–8.89] [non‐HDL‐C HR_ASCVD=4.60, 95% CI 1.98–10.70; LDL‐C HR_death=3.74, 95% CI 2.03–6.88]). Consistent HDL‐C concentrations <40 mg/dL were associated with greater ASCVD and mortality risk than concentrations >70 mg/dL (HR_ASCVD=3.81, 95% CI 2.04–7.15; HR_death=2.88, 95% CI 1.70–4.89). Triglycerides trajectories were unassociated with outcomes.

Conclusions

Using a longitudinal modeling technique, we demonstrated that unfavorable lipid trajectories over 35 years confer higher ASCVD and mortality risk later in life.

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Harmonizing lipidomics: NIST interlaboratory comparison exercise for lipidomics using SRM 1950-Metabolites in Frozen Human Plasma

As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks for intra- and interlaboratory quality control and method validation. These analyses were performed using nonstandardized laboratory-independent workflows. The consensus locations were also compared with a previous examination of SRM 1950 by the LIPID MAPS consortium. While the central theme of the interlaboratory study was to provide values to help harmonize lipids, lipid mediators, and precursor measurements across the community, it was also initiated to stimulate a discussion regarding areas in need of improvement.