Association of Coronary Plaque With Low-Density Lipoprotein Cholesterol Levels and Rates of Cardiovascular Disease Events Among Symptomatic Adults

Cardiovascular risk and subclinical atherosclerosis in first-degree relatives of patients with premature cardiovascular disease

Background

Screening first-degree relatives (FDRs) of patients with premature coronary artery disease (CAD) is recommended but not routinely performed.

Objectives

To assess the diagnostic yield and impact on clinical management of a clinical and imaging-based screening program of FDRs delivered in the setting of routine clinical care.

Methods

We recruited FDRs of patients with premature CAD with no personal history of CAD and prospectively assessed for: 1) cardiovascular risk and presence of significant subclinical atherosclerosis (SA) defined as plaque on carotid ultrasound, stenosis >50% or extensive atherosclerosis on coronary computed tomography angiography, or coronary artery calcium scores >100 Agatston units or >75% percentile for age and sex; 2) utilization of preventive medications and lipid levels prior enrolment and after completion of the assessment.

Results

We assessed 132 FDRs (60.6% females), mean (SD) age 47(17) years old. Cardiovascular risk was high in 38.2%, moderate in 12.2%, and low in 49.6% of FDRs. SA was present in 34.1% of FDRs, including 12.5% in low, 51.9% in moderate, and 55.0% in high calculated risk groups. After assessment, LLT was initiated in 32.6% of FDRs and intensified in 16.0% leading to mean (SD) LDL-C decrease of 1.07(1.10) mmol/L in patients with high calculated risk or SA. LLT was recommended to all patients with high calculated risk, but those with SA were more likely to receive the medications from pharmacies (93.3% vs 60.0%, p = 0.006).

Conclusion

Screening the FDRs of patients with premature CAD is feasible, may have high diagnostic yield and impact risk factor management.

Cardiovascular Risk Estimation and Stratification Among Individuals with Hypercholesterolemia

PURPOSE OF THE REVIEW

This review aims to assess the variability in considering hypercholesterolemia for cardiovascular risk stratification in the general population. Recent literature on the integration of hypercholesterolemia into clinical risk scores and its interaction with other risk factors will be explored.

RECENT FINDINGS

The impact of hypercholesterolemia on risk estimation varies among different cardiovascular risk calculators. Elevated lipid levels during early life stages contribute to atherosclerotic plaque development, influencing disease severity despite later treatment initiation. The interplay between low-density lipoprotein cholesterol (LDLc), inflammatory markers and non-LDL lipid parameters enhances cardiovascular risk stratification. Studies have also examined the role of coronary artery calcium (CAC) score as a negative risk marker in populations with severe hypercholesterolemia. Furthermore, polygenic risk scores (PRS) may aid in diagnosing non-monogenic hypercholesterolemia, refining cardiovascular risk stratification and guiding lipid-lowering therapy strategies. Understanding the heterogeneity in risk estimation and the role of emerging biomarkers and imaging techniques is crucial for optimizing cardiovascular risk prediction and guiding personalized treatment strategies in individuals with hypercholesterolemia.

Discrepancies between Coronary Artery Calcium Score and Coronary Artery Disease Severity in Computed Tomography Angiography Studies

The aim of this paper is to demonstrate the difference in usefulness of the coronary artery calcium score (CACS) and the full assessment of the severity of coronary artery disease in coronary computed tomography angiography (CCTA) studies. The difference between the population risk of coronary artery disease (CAD) assessed by the CACS and the severity of CAD was demonstrated in images from two CCTA studies. The first image is from a patient with a CACS of 0 and significant coronary artery stenosis. In the native phase of CCTA examination, no calcified changes were detected in the topography of the coronary arteries. In the middle section of the left descending artery (LAD), at the level of the second diagonal branch (Dg2), a large non-calcified atherosclerotic plaque was visible. Mid-LAD stenosis was estimated to be approximately 70%. The second image features a patient with a high CACS but no significant coronary artery stenosis. The calcium score of individual coronary arteries calculated using the Agatston method was as follows: left main (LM) 0, LAD 403, left circumflex (LCx) 207.7, right coronary artery (RCA) 12. CACS was 622.7, representing a significant population risk of significant CAD. In the proximal and middle sections of the LAD, numerous calcified and mixed atherosclerotic plaques with positive remodeling were visible, causing stenosis of 25-50%. Similarly, in the proximal and middle sections of the LCx, numerous calcified and mixed atherosclerotic plaques with positive remodeling were visualized, causing stenoses of 25-50%. Calcified atherosclerotic plaques were found in the RCA, causing stenosis <25%. The entire CCTA image met CAD-RADS 2 (coronary artery disease reporting and data system) criteria. In summary, CACS may be applicable in population-based studies to assess the risk of significant CAD. In the evaluation of individual patients, a comprehensive assessment of CAD severity based on the angiographic phase of the CCTA examination should be used.

Environmental Heavy Metal Exposure and Associated Cardiovascular Diseases in Light of the Triglyceride Glucose Index

Cardiovascular diseases (CVD), primarily ischemic heart disease and stroke, remain leading global health burdens. Environmental risk factors have a major role in the development of CVD, particularly exposure to heavy metals. The Triglyceride Glucose Index (TyG), a measure of insulin resistance and CVD risk, is the primary focus of this study, which summarizes the most recent findings on the effects of lead (Pb), arsenic (As), and cadmium (Cd) on CVD risk. A higher risk of CVD is correlated with an elevated TyG index, which has been linked to insulin resistance. Exposure to Cd is associated with disturbance of lipid metabolism and oxidative stress, which increases the risk of CVD and TyG. Exposure reduces insulin secretion and signaling, which raises the TyG index and causes dyslipidemia. Pb exposure increases the risk of CVD and TyG index via causing oxidative stress and pancreatic β-cell destruction. These results highlight the need of reducing heavy metal exposure by lifestyle and environmental modifications in order to lower the risk of CVD. To comprehend the mechanisms and create practical management plans for health hazards associated with heavy metals, more study is required.

Lipoprotein(a) and Coronary Plaque in Asymptomatic Individuals: The Miami Heart Study at Baptist Health South Florida

BACKGROUND

Elevated levels of lipoprotein(a) (Lp(a)) are independently associated with an increased risk of atherosclerotic cardiovascular disease events. However, the mechanisms driving this association are poorly understood. We aimed to evaluate the association between Lp(a) and coronary plaque characteristics in a contemporary US cohort without clinical atherosclerotic cardiovascular disease, undergoing coronary computed tomography angiography, the noninvasive gold standard for the assessment of coronary atherosclerosis.

METHODS

We used baseline data from the Miami Heart Study-a community-based, prospective cohort study-which included asymptomatic adults aged 40 to 65 years evaluated using coronary computed tomography angiography. Those taking any lipid-lowering therapies were excluded. Elevated Lp(a) was defined as ≥125 nmol/L. Outcomes included any plaque, coronary artery calcium score >0, maximal stenosis ≥50%, presence of any high-risk plaque feature (positive remodeling, spotty calcification, low-attenuation plaque, napkin ring), and the presence of ≥2 high-risk plaque features.

RESULTS

Among 1795 participants (median age, 52 years; 54.3% women; 49.6% Hispanic), 291 (16.2%) had Lp(a) ≥125 nmol/L. In unadjusted analyses, individuals with Lp(a) ≥125 nmol/L had a higher prevalence of all outcomes compared with Lp(a) <125 nmol/L, although differences were only statistically significant for the presence of any coronary plaque and ≥2 high-risk features. In multivariable models, elevated Lp(a) was independently associated with the presence of any coronary plaque (odds ratio, 1.40, [95% CI, 1.05-1.86]) and with ≥2 high-risk features (odds ratio, 3.94, [95% CI, 1.82-8.52]), although only 35 participants had this finding. Among participants with a coronary artery calcium score of 0 (n=1200), those with Lp(a) ≥125 nmol/L had a significantly higher percentage of any plaque compared with those with Lp(a) <125 nmol/L (24.2% versus 14.2%; P<0.001).

CONCLUSIONS

In this contemporary analysis, elevated Lp(a) was independently associated with the presence of coronary plaque. Larger studies are needed to confirm the strong association observed with the presence of multiple high-risk coronary plaque features.

Age- and sex-based heterogeneity in coronary artery plaque presence and burden in familial hypercholesterolemia: A multi-national study

Objectives

Individuals with familial hypercholesterolemia (FH) are at an increased risk for coronary artery disease (CAD). While prior research has shown variability in coronary artery calcification (CAC) among those with FH, studies with small sample sizes and single-center recruitment have been limited in their ability to characterize CAC and plaque burden in subgroups based on age and sex. Understanding the spectrum of atherosclerosis may result in personalized risk assessment and tailored allocation of costly add-on, non-statin lipid-lowering therapies. We aimed to characterize the presence and burden of CAC and coronary plaque on computed tomography angiography (CTA) across age- and sex-stratified subgroups of individuals with FH who were without CAD at baseline.

Methods

We pooled 1,011 patients from six cohorts across Brazil, France, the Netherlands, Spain, and Australia. Our main measures of subclinical atherosclerosis included CAC ranges (i.e., 0, 1-100, 101-400, >400) and CTA-derived plaque burden (i.e., no plaque, non-obstructive CAD, obstructive CAD).

Results

Ninety-five percent of individuals with FH (mean age: 48 years; 54% female; treated LDL-C: 154 mg/dL) had a molecular diagnosis and 899 (89%) were on statin therapy. Overall, 423 (42%) had CAC=0, 329 (33%) had CAC 1-100, 160 (16%) had CAC 101-400, and 99 (10%) had CAC >400. Compared to males, female patients were more likely to have CAC=0 (48% [n = 262] vs 35% [n = 161]) and no plaque on CTA (39% [n = 215] vs 26% [n = 120]). Among patients with CAC=0, 85 (20%) had non-obstructive CAD. Females also had a lower prevalence of obstructive CAD in CAC 1-100 (8% [n = 15] vs 18% [n = 26]), CAC 101-400 (32% [n = 22] vs 40% [n = 36]), and CAC >400 (52% [n = 16] vs 65% [n = 44]). Female patients aged 50-59 years were less likely to have obstructive CAD in CAC >400 (55% [n = 6] vs 70% [n = 19]).

Conclusion

In this large, multi-national study, we found substantial age- and sex-based heterogeneity in CAC and plaque burden in a cohort of predominantly statin-treated individuals with FH, with evidence for a less pronounced increase in atherosclerosis among female patients. Future studies should examine the predictors of resilience to and long-term implications of the differential burden of subclinical coronary atherosclerosis in this higher risk population.

Non-calcified plaque in asymptomatic patients with zero coronary artery calcium score: A systematic review and meta-analysis

BACKGROUND

There is growing interest in understanding the coronary atherosclerotic burden in asymptomatic patients with zero coronary artery calcium score (CACS). In this population, we aimed to investigate the prevalence and severity of non-calcified coronary plaques (NCP) as detected by coronary CT angiography (CCTA), and to analyze the associated clinical predictors.

METHODS

This was a systematic review with meta-analysis of studies indexed in PubMed/Medline and Web of Science from inception of the database to March 31st, 2023. Using the random-effects model, separate Forest and Galbraith plots were generated for each effect size assessed. Heterogeneity was assessed using the I2 statistics whilst Funnel plots and Egger's test were used to assess for publication bias.

RESULTS

From a total of 14 studies comprising 37808 patients, we approximated the pooled summary estimates for the overall prevalence of NCP to be 10% (95%CI: 6%-13%). Similarly, the pooled prevalence of obstructive NCP was estimated at 1.1% (95%CI: 0.7%-1.5%) from a total of 10 studies involving 21531 patients. Hypertension [OR: 1.46 (95%CI:1.31-1.62)] and diabetes mellitus [OR: 1.69 (95%CI: 1.41-1.97)] were significantly associated with developing any NCP, with male gender being the strongest predictor [OR: 3.22 (95%CI: 2.17-4.27)].

CONCLUSION

There is a low burden of NCP among asymptomatic subjects with zero CACS. In a subset of this population who have clinical predictors of NCP, the addition of CCTA has a potential to provide a better insight about occult coronary atherosclerosis, however, a risk-benefit approach must be factored in prior to CCTA use given the low prevalence of NCP.

[Coronary CT angiography and coronary atherosclerosis : Where do we stand today?]

Cardiac computed tomography (CT) has made substantial progress in recent years. The main field of application is CT coronary angiography for visualization of the coronary arteries and for the detection and exclusion of coronary artery stenosis. This has been included in international guidelines for the management of stable coronary artery disease or chronic coronary syndrome as well as for the diagnostic work-up of patients with acute chest pain; however, it must be taken into account that the diagnostic validity is only sufficiently high when the image quality is good and therefore alternative diagnostic procedures should be included in patients where an unrestricted good image quality is not to be expected. The fact that CT angiography enables the detection not only of coronary stenosis but also of nonobstructive atherosclerotic plaque is interesting for the estimation of the risk of atherosclerotic events. It is practically certain that in the absence of detectable atherosclerotic plaque in CT angiography, statin treatment does not lower the risk of atherosclerotic events. To what extent CT is suitable to provide indications for statin treatment and the threshold for which the presence of nonobstructive plaque should prompt initiation of statin treatment are currently the subject of intensive research.

Is there an association between coronary artery inflammation and coronary atherosclerotic burden?

Background

As for the coronary artery inflammation and coronary atherosclerotic burden, which are used to assess the risk of adverse cardiac events in patients, it is unclear whether there is any certain correlation between them. Therefore, the purpose of this study was to explore the potential relationship between coronary artery inflammation and coronary atherosclerotic burden.

Methods

A total of 346 eligible patients underwent assessment of computed tomography (CT) attenuation values of pericoronary adipose tissue (PCAT) in the right coronary artery and Agatston coronary artery calcium (CAC) based on coronary CT angiography. These measurements were utilized to evaluate coronary inflammation and atherosclerotic burden, respectively. Patients with a CAC score of 0 were categorized into groups based on the presence or absence of coronary artery disease (CAD). CAC scores of 10, 100, and 400 were chosen as cutoff values to compare differences in PCAT attenuation values across different CAC scores.

Results

When comparing all CAD patients to non-CAD patients, a significantly higher PCAT attenuation was observed in CAD patients (-87.54±9.39 vs. -93.45±7.42 HU, P=0.000). The PCAT attenuation in CAD patients with a CAC score of 0 was significantly higher than that in patients with a CAC score greater than 0 and in non-CAD patients with a CAC score of 0 (-82.63±8.70 vs. -90.38±8.59 vs. -93.45±7.42 HU, P=0.000). The PCAT attenuation values did not exhibit significant differences among different CAC scores (all P>0.05); however, it was highest in CAD patients with a CAC score of 0 (P<0.05). Body mass index, hyperlipidemia, hypertension, and PCAT attenuation were identified as independent risk factors in both CAD patients with a CAC score of 0 and patients with a CAC score greater than 0 (all P<0.05).

Conclusions

The results of this study suggest that a direct relationship between coronary inflammation and coronary atherosclerotic burden is not evident. Nonetheless, it is noteworthy that coronary inflammation was most pronounced in CAD patients with a CAC score of 0, while CAC score did not demonstrate an association with inflammation.

Interplay between Risk Factors and Coronary Artery Calcium in Middle-Aged and Elderly Symptomatic Patients

Background

The prognostic value of coronary artery calcium (CAC) combined with risk factor burdens in middle-aged and elderly patients with symptoms is unclear.

Methods

A cohort study comprising 7432 middle-aged and elderly symptomatic patients (aged above 55 years) was conducted between December 2013 and September 2020. All patients had undergone coronary computed tomography angiography, and the Agatston score were used to measure CAC scores. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), which was defined as a composite outcome of nonfatal myocardial infarction, revascularization (percutaneous coronary intervention or coronary artery bypass graft), stroke, and cardiovascular death. Congestive heart failure, cardiogenic shock, malignant arrhythmia, and all-cause mortality were defined as the secondary outcomes.

Results

There are 970 (13%) patients with CAC 0-10, 2331 (31%) patients with CAC 11-100, and 4131 (56%) patients with CAC ≥ 101. The proportion of patients aged 55-65 years, 65-75 years and ≥ 75 years was 40.7%, 38.1% and 21.2%, respectively. The total number of MACCEs over the 3.4 years follow-up period was 478. The percentage of CAC ≥ 101 was higher among the 75-year-old group than the 55-65-year-old group, increasing from 46.5% to 68.2%. With the increase in the CAC score, the proportion of patients aged ≥ 75 years increased from 12.9% to 25.8%, compared to those aged 55-65 years. The number of risk factors gradually increased as the CAC scores increased in the symptomatic patients aged over 55 years and the similar tendencies were observed among the different age subgroups. The proportion of non-obstructive coronary artery disease (CAD) was comparable between the three age groups (53.5% vs 51.9% vs 49.1%), but obstruction CAD increased with age. The incidence of MACCE in the group with CAC ≥ 101 and ≥ 4 risk factors was 1.71 times higher (95% confidence interval (CI) 1.01-2.92; p = 0.044) than the rate in the group with CAC ≥ 101 and 1 risk factor. In the CAC 0-10 group, the incidence of MACCE in patients aged ≥ 75 years was 12.65 times higher (95% CI: 6.74-23.75; p < 0.0001) than that in patients aged 55-65 years. By taking into account the combination of CAC score, age, and risk factor burden, the predictive power of MACCE can be increased (area under the curve (AUC) = 0.614).

Conclusions

In symptomatic patients aged 55 or above, a rise in age, CAC scores, and risk factor burden was linked to a considerable risk of future MACCE. In addition, combining CAC scores, age and risk factors can more accurately predict outcomes for middle-aged and elderly patients with symptoms.

Historical Review of the Use of Relative Risk Statistics in the Portrayal of the Purported Hazards of High LDL Cholesterol and the Benefits of Lipid-Lowering Therapy

The manner in which clinical trial investigators present their findings to healthcare providers and the public can have a substantial influence on their impact. For example, if a heart attack occurs in 2% of those in the placebo group and in 1% of those in the drug-treated group, the benefit to the treated population is only one percentage point better than no treatment. This finding is unlikely to generate much enthusiasm from the study sponsors and in the reporting of the findings to the public. Instead, trial directors can amplify the magnitude of the appearance of the treatment benefit by using the relative risk (RR) value of a 50% reduction of the risk of a heart attack, since one is 50% of two. By using the RR type of data analysis, clinical trial directors can promote the outcome of their trial in their publication and to the media as highly successful while minimizing or disregarding entirely the absolute risk (AR) reduction of only one percentage point. The practice of expressing the RR without the AR has become routinely deployed in the reporting of findings in many different areas of clinical research. We have provided a historical perspective on how this form of data presentation has become commonplace in the reporting of findings from randomized controlled trials (RCTs) on coronary heart disease (CHD) event monitoring and prevention over the past four decades. We assert that the emphasis on RR coupled with insufficient disclosure of AR in the reporting of RCT outcomes has led healthcare providers and the public to overestimate concerns about high cholesterol and to be misled as to the magnitude of the benefits of cholesterol-lowering therapy. The goal of this review is to prompt the scientific community to address this misleading approach to data presentation.

Advanced subclinical atherosclerosis: A novel category within the cardiovascular risk continuum with distinct treatment implications

Traditionally, guidelines divide patients into primary and secondary prevention for atherosclerotic cardiovascular disease (ASCVD) risk management. However, the modern understanding of the biological progression of atherosclerosis is inconsistent with this binary approach. Therefore, a new approach demonstrating both atherosclerosis and ASCVD risk as a continuum is needed to give clinicians a framework for better matching risk and intensity of therapy. Advances in coronary imaging have most clearly brought this problem into view, as for example coronary artery calcium (CAC) scoring has shown that some individuals in the primary prevention have equal or higher ASCVD risk as certain subgroups in secondary prevention. This article introduces "advanced subclinical atherosclerosis" as a new and distinct clinical group that sits between the traditional groups of primary and secondary prevention. Importantly, this article also introduces a new graphic to visualize this intermediate population that is explicitly based on plaque burden. The aim of the graphic is both to educate and to allow for better identification of a patient's cardiovascular risk and guide more effective risk-based management.

Associations of non-HDL-C and triglyceride/HDL-C ratio with coronary plaque burden and plaque characteristics in young adults

Coronary artery disease (CAD) is uncommon in young adult patients. However, these patients have different risk factor profiles and high-risk coronary plaques are more common. The aim of this study was to examine the relations between the coronary plaque burden, plaque composition, serum non-high-density lipoprotein cholesterol (non-HDL-C) levels, and triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio in young adults. We analyzed a total of 551 patients under age 45 who had undergone coronary computed tomography angiography (CCTA). Coronary plaque characteristics were analyzed using CCTA. Multivariate linear regression analysis was used to assess the predictors of non-calcified plaque (NCB) and calcified plaque (CB) burdens. Serum non-HDL-C levels and TG/HDL-C ratio were higher in the coronary atherosclerosis patient group. Serum non-HDL-C levels and the TG/HDL-C ratio were higher in the obstructive CAD patient group. The plaque burden was positively correlated with non-HDL-C (r = 0.30; p < 0.001), and TG/HDL-C ratio (r = 0.18; p < 0.001).  NCB was positively correlated with age, gender, smoking status, fasting blood glucose, total cholesterol, low-density lipoprotein cholesterol, serum triglycerides, hbA1c, non-HDL-C, and TG/HDL-C ratio. Non-HDL-C (β coefficient = 0.13; p = 0.023) and TG/HDL-C ratio (β = 0.10;  p = 0.042) were independent predictors of NCB. Serum non-HDL-C levels and TG/HDL-C were significantly associated with the presence and burden of coronary plaques. Serum non-HDL-C and TG/HDL-C ratios were independently associated with NCB, suggesting their use as easy-to-compute markers for identifying high-risk groups in young adults.

Subclinical atherosclerosis determined by coronary artery calcium deposition in patients with clinical familial hypercholesterolemia

Background and aims

Limited knowledge exists regarding the association between coronary artery calcium (CAC) deposition in patients with clinical familial hypercholesterolemia (FH) and FH subtypes such as polygenic causes. We studied CAC score in patients with clinical FH and subtypes including polygenic causes of FH compared to healthy controls.

Methods

In a case-control study, we identified potential clinical FH cases registered with an LDL-C >6.7 mmol/l within a nationwide clinical laboratory database on the Faroe Islands and invited them for diagnostic evaluation according to clinical FH scoring systems. Controls were identified in the background population. All subjects were aged 18-75 years and without a history of cardiovascular disease. FH mutation testing and genotypes of twelve LDL-C associated single nucleotide polymorphisms were determined using conventional methods in selected individuals. CAC scores were assessed by cardiac CT. Odds ratios obtained using multivariate logistic regression were used as measures of association.

Results

A total of 120 clinical FH patients and 117 age- and sex-matched controls were recruited. We found a very low frequency of monogenic FH (3%), but a high level of polygenic FH (60%) in those genetically tested (54%). There was a statistically significant association between the CAC score and a diagnosis of clinical FH with the highest observed odds ratio of 5.59 (95% CI 1.65; 18.94, p = 0.006) in those with a CAC score ≥300 compared to those with a CAC of zero. In supplemental analyses, there was a strong association between CAC scores and clinical FH of a polygenic cause.

Conclusion

We found a statistically significant association between CAC levels and clinical FH with the highest observed risk estimates among clinical FH cases of a presumed polygenic cause.

Do statins benefit low-risk population for primary prevention of atherosclerotic cardiovascular disease: A retrospective cohort study

The reported beneficial effects of statins on cardiovascular outcome based on risk assessment are inconsistent. Therefore, we investigated statin therapy effectiveness for the primary prevention of cardiovascular disease (CVD), according to the Korean Risk Prediction Model (KRPM). Subjects aged 40–79 years with low density lipoprotein cholesterol (LDL-C) of < 190 mg/dL and without CVD history were categorized as statin users or non-users using the National Health Insurance Service-National Sample Cohort (NHIS-NSC) database, Korea, 2002–2015. The 10-year atherosclerotic CVD (ASCVD) risk was calculated using the validated KRPM and categorized as low, borderline, intermediate, or high-risk groups; the incidence of major adverse cardiovascular events (MACEs) was compared over a mean follow-up period of 5.7 years using Cox proportional hazard models. The MACE incidence risk was decreased in statin users [hazard ratio (HR) 0.90, 95% confidence interval (CI) (0.84–0.98)]. However, there was an increased risk of MACE incidence in low-risk statin users [HR 1.80, 95% CI (1.29–2.52)], and no significant relationship was identified between statin use and MACE in the borderline [HR 1.15, 95% CI (0.86–1.54)] and intermediate-risk [HR 0.94, 95% CI (0.85–1.03)] groups. The risk of MACE incidence decreased only in the high CVD risk group among statin users. Statin use is not associated with MACE reduction in low- to intermediate-risk participants. Therefore, individuals with LDL-C level of < 190 mg/dL and low ASCVD risk should consider statin therapy only when CVD risk is proved obvious using an appropriate ASCVD risk tool.

Statin therapy is not warranted for a person with high LDL-cholesterol on a low-carbohydrate diet

PURPOSE OF REVIEW

Although there is an extensive literature on the efficacy of the low carbohydrate diet (LCD) for weight loss and in the management of type 2 diabetes, concerns have been raised that the LCD may increase cardiovascular disease (CVD) risk by increasing the level of low-density lipoprotein cholesterol (LDL-C). We have assessed the value of LDL-C as a CVD risk factor, as well as effects of the LCD on other CVD risk factors. We have also reviewed findings that provide guidance as to whether statin therapy would be beneficial for individuals with high LDL-C on an LCD.

RECENT FINDINGS

Multiple longitudinal trials have demonstrated the safety and effectiveness of the LCD, while also providing evidence of improvements in the most reliable CVD risk factors. Recent findings have also confirmed how ineffective LDL-C is in predicting CVD risk.

SUMMARY

Extensive research has demonstrated the efficacy of the LCD to improve the most robust CVD risk factors, such as hyperglycemia, hypertension, and atherogenic dyslipidemia. Our review of the literature indicates that statin therapy for both primary and secondary prevention of CVD is not warranted for individuals on an LCD with elevated LDL-C who have achieved a low triglyceride/HDL ratio.

Can low-carbohydrate diets be recommended for reducing cardiovascular risk?

PURPOSE OF REVIEW

This review provides a rationale for implementing carbohydrate restriction as a dietary therapy to improve biomarkers of cardiovascular health and suggests that this will require a paradigm shift away from what is currently promulgated as a 'heart-healthy' diet.

RECENT FINDINGS

Type 2 diabetes mellitus (T2DM), metabolic syndrome, and related co-morbidities are major risk factors for cardiovascular disease (CVD). Ideally, then, a diet intended to support cardiovascular health should be one that improves or reverses these underlying risk factors. Carbohydrate restriction is effective for this purpose as well as for favorably impacting atherogenic dyslipidemia. Recent consensus reports from select national organizations have endorsed low-carbohydrate diets for improving glycemia and cardiovascular risk. Reluctance among public health organizations and some clinicians to more widely promote this therapeutic nutritional approach is driven primarily by the increase in serum low-density lipoprotein cholesterol (LDL-C) observed in a proportion of individuals who adopt a low-carbohydrate diet. Here we explore the rationale for using carbohydrate restriction to improve cardiovascular health by way of favorably impacting T2DM and insulin resistance, and why this salutary effect outweighs the potential adverse effects of an increase in serum LDL-C.

SUMMARY

Carbohydrate restriction is a logical foundation for a dietary intervention intended to reduce CVD risk, particularly among individuals with T2DM or metabolic syndrome.

Importance of Coagulation Factors as Critical Components of Premature Cardiovascular Disease in Familial Hypercholesterolemia

For almost a century, familial hypercholesterolemia (FH) has been considered a serious disease, causing atherosclerosis, cardiovascular disease, and ischemic stroke. Closely related to this is the widespread acceptance that its cause is greatly increased low-density-lipoprotein cholesterol (LDL-C). However, numerous observations and experiments in this field are in conflict with Bradford Hill’s criteria for causality. For instance, those with FH demonstrate no association between LDL-C and the degree of atherosclerosis; coronary artery calcium (CAC) shows no or an inverse association with LDL-C, and on average, the life span of those with FH is about the same as the surrounding population. Furthermore, no controlled, randomized cholesterol-lowering trial restricted to those with FH has demonstrated a positive outcome. On the other hand, a number of studies suggest that increased thrombogenic factors—either procoagulant or those that lead to high platelet reactivity—may be the primary risk factors in FH. Those individuals who die prematurely have either higher lipoprotein (a) (Lp(a)), higher factor VIII and/or higher fibrinogen compared with those with a normal lifespan, whereas their LDL-C does not differ. Conclusions: Many observational and experimental studies have demonstrated that high LDL-C cannot be the cause of premature cardiovascular mortality among people with FH. The number who die early is also much smaller than expected. Apparently, some individuals with FH may have inherited other, more important risk factors than a high LDL-C. In accordance with this, our review has shown that increased coagulation factors are the commonest cause, but there may be other ones as well.

Visual Coronary and Aortic Calcium Scoring on Chest Computed Tomography Predict Mortality in Patients With Low-Density Lipoprotein-Cholesterol ≥190 mg/dL

BACKGROUND

Current guidelines recommend coronary artery calcium (CAC) scoring for stratification of atherosclerotic cardiovascular disease risk only in patients with borderline to intermediate risk score by the pooled cohort equation with low-density lipoprotein-cholesterol (LDL-C) of 70 to 190 mg/dL. It remains unknown if CAC or thoracic aorta calcification (TAC), detected on routine chest computed tomography, can provide further risk stratification in patients with LDL-C≥190 mg/dL.

METHODS

From a multisite medical center, we retrospectively identified all patients from March 2005 to June 2021 age ≥40 years, without established atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL who had non-gated non-contrast chest computed tomography within 3 years of LDL-C measurement. Ordinal CAC and TAC scores were measured by visual inspection. Kaplan-Meier curves and multivariable Cox-regression models were built to ascertain the association of CAC and TAC scores with all-cause mortality.

RESULTS

We included 811 patients with median age 59 (53-68) years, 262 (32.3%) were male, and LDL-C median level was 203 (194-217) mg/dL. Patients were followed for 6.2 (3.29-9.81) years, and 109 (13.4%) died. Overall, 376 (46.4%) of patients had CAC=0 and 226 (27.9%) had TAC=0. All-cause mortality increased with any CAC and moderate to severe TAC. In a multivariate model, patients with CAC had a significantly higher mortality compared with those without CAC: mild hazard ratio (HR), 1.71 (1.03-2.83), moderate HR, 2.12 (1.14-3.94), and severe HR, 3.49 (1.94-6.27). Patients with moderate TAC (HR, 2.34 [1.19-4.59]) and those with severe TAC (HR, 3.02 [1.36-6.74]) had higher mortality than those without TAC.

CONCLUSIONS

In patients without history of atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL, the presence and severity of CAC and TAC are independently associated with all-cause mortality.