Lipoprotein Sub-Fractions by Ion-Mobility Analysis and Its Association with Subclinical Coronary Atherosclerosis in High-Risk Individuals

AIMS

There is limited knowledge about the association of lipoprotein particles and markers of coronary atherosclerosis such as coronary artery calcification (CAC) in relatively young high-risk persons. This study examines the association of lipoprotein subfractions and CAC in high cardiometabolic risk individuals.

METHODS

The study presents analysis from baseline data of a randomized trial targeted at high-risk workers. Employees of Baptist Health South Florida with metabolic syndrome or diabetes were recruited. At baseline, all 182 participants had lipoprotein subfraction analysis using the ion mobility technique and participants above 35 years (N=170) had CAC test done. Principal components (PC) were computed for the combination of lipoprotein subclasses. Multiple bootstrapped regression analyses (BSA) were conducted to assess the relationship between lipoprotein subfractions and CAC.

RESULTS

The study population (N=170) was largely female (84%) with a mean age of 58 years. Three PCs accounted for 88% variation in the sample. PC2, with main contributions from VLDL particles in the positive direction and large LDL particles in the negative direction was associated with a 22% increase in CAC odds (P value ＜0.05 in 100% of BSA). PC3, with main contributions from HDL lipoprotein particles in the positive direction and small/medium LDL and large IDL particles in the negative direction, was associated with a 9% reduction in CAC odds (P＜0.05 in 88% of BSA). PC1, which had approximately even contributions from HDL, LDL, IDL and VLDL lipoprotein subfractions in the positive direction, was not associated with CAC.

CONCLUSION

In a relatively young but high-risk population, a lipoprotein profile predominated by triglyceride-rich lipoproteins was associated with increased risk of CAC, while one predominated by HDL lipoproteins offered modest protection. Lipoprotein sub-fraction analysis may help to further discriminate patients who require more intensive cardiovascular work-up and treatment.

Introducing the 'Drucebo' effect in statin therapy: a systematic review of studies comparing reported rates of statin-associated muscle symptoms, under blinded and open-label conditions

BACKGROUND

The 'placebo effect' and 'nocebo effect' are phenomena whereby beneficial (placebo) or adverse (nocebo) effects result from the expectation that an inert substance will relieve or cause a particular symptom. These terms are often inappropriately applied to effects experienced on drug therapy. Quantifying the magnitude of placebo and nocebo effects in clinical trials is problematic because it requires a 'no treatment' arm. To overcome the difficulties associated with measuring the nocebo effect, and the fact that its definition refers to inert compounds, rather than drugs, we introduce the concept of 'drucebo' (a combination of DRUg and plaCEBO or noCEBO) to relate to beneficial or adverse effects of a drug, which result from expectation and are not pharmacologically caused by the drug. As an initial application of the concept, we have estimated the contribution of the drucebo effect to statin discontinuation and statin-induced muscle symptoms by performing a systematic review of randomized controlled trial of statin therapy.

METHODS

This preferred reporting items for systematic reviews and meta-analysis-compliant systematic review was prospectively registered in PROSPERO (CRD42017082700). We searched PubMed and Cochrane Central from inception until 3 January 2018 using a search strategy designed to detect studies including the concepts (Statins AND Placebo AND muscle pain). We included studies that allowed us to quantify the drucebo effect for adverse muscle symptoms of statins by (i) comparing reported rates of muscle symptoms in blinded and unblinded phases of randomized controlled trials and (ii) comparing rates of muscle symptoms at baseline and during blinded therapy in trials that included patients with objectively confirmed statin intolerance at baseline. Extraction was performed by two researchers with disagreements settled by a third reviewer.

RESULTS

Five studies allowed the estimation of the drucebo effect. All trials demonstrated an excess of side effects under open-label conditions. The contribution of the drucebo effect to statin-associated muscle pain ranged between 38% and 78%. The heterogeneity of study methods, outcomes, and reporting did not allow for quantitative synthesis (meta-analysis) of the results.

CONCLUSIONS

The drucebo effect may be useful in evaluating the safety and efficacy of medicines. Diagnosis of the drucebo effect in patients presenting with statin intolerance will allow restoration of life-prolonging lipid-lowering therapy. Our study was limited by heterogeneity of included studies and lack of access to individual patient data. Further studies are necessary to better understand risk factors for and clinical management of the drucebo effect.

Online Health Searches and Their Perceived Effects on Patients and Patient-Clinician Relationships: ASystematic Review

Online health searches are common and may be impacting patients and their relationships with their clinicians in ways that are not fully understood. We searched PubMed, Embase, Cochrane Reviews, Cochrane Trials, Scopus, and CINAHL from January 1, 1990 to January 29, 2016 for studies in which patients searched online for any aspect of health care and then visited their clinician. We extracted data pertaining to either patients' or clinicians' perceptions of the effects of these online searches on patients and the patient-clinician relationship. Searches seemed to induce patient anxiety but more often led to patient reassurance, clinical understanding, and empowerment. Patients tended to perceive that online health searches had a positive effect on the patient-clinician relationship, although the nature of the effect could depend on the clinician's response to patient queries about the information. Clinicians generally perceived neutral effects on patients and the patient-clinician relationship and commonly raised concerns about the accuracy of online content. Significant methodologic heterogeneity prevented quantitative synthesis. Accuracy of online health search content was not assessed, and randomized controlled trials were notably lacking.

The spectrum of type III hyperlipoproteinemia

BACKGROUND

Type III hyperlipoproteinemia is a highly atherogenic dyslipoproteinemia characterized by hypercholesterolemia and hypertriglyceridemia due to markedly increased numbers of cholesterol-enriched chylomicron and very-low-density lipoprotein (VLDL) remnant lipoprotein particles. Type III can be distinguished from mixed hyperlipidemia based on a simple diagnostic algorithm, which involves total cholesterol, triglycerides, and apolipoprotein B (apoB). However, apoB is not measured routinely.

OBJECTIVE

The objective of the present study was to determine if patients with type III could be distinguished from mixed hyperlipidemia based on lipoprotein lipids.

METHODS

Classification was based first on total cholesterol and triglyceride and then on the apoB diagnostic algorithm using apoB plus total cholesterol plus triglycerides, and validated by sequential ultracentrifugation. Four hundred and forty normals, 637 patients with hypertriglyceridemia, and 714 with hypertriglyceridemia and hypercholesterolemia were studied. Plasma lipoproteins were separated by sequential ultracentrifugation and heparin-manganese precipitation. Cholesterol, triglyceride, and apoB were measured in plasma and isolated lipoprotein fractions.

RESULTS

Of the 1351 patients with hypertriglyceridemia, 49 had type III hyperlipoproteinemia, as diagnosed by the apoB algorithm and validated by ultracentrifugation. Plasma triglycerides were higher in the type III subjects: 4.16 mmol/L (3.35-6.08, 25th-75th percentile), but there was considerable overlap with the hypertriglyceridemic subjects 2.65 mmol/L (1.91-4.20, 25th-75th percentile) and the combined hyperlipidemic subjects 3.02 mmol/L (2.07-5.32, 25th-75th percentile). Similarly, total cholesterol was 4.79 mmol/L (4.31-5.58, 25th-75th percentile) for type III vs 5.5 mmol/L (4.64-5.78, 25th-75th percentile) and 7.02 mmol/L (6.39-7.96, 25th-75th percentile), respectively. By contrast, as identified by the apoB algorithm, the VLDL-C/TG, VLDL-C/VLDL-TG, VLDL-C/VLDL apoB, and VLDL apoB/LDL apoB ratios were all higher in type III than in the other hypertriglyceridemic dyslipoproteinemias with the exception of type V as diagnosed by the apoB algorithm.

CONCLUSION

Cholesterol and triglycerides cannot reliably distinguish type III hyperlipoproteinemia from mixed hyperlipidemia. Adding apoB and applying the apoB algorithm makes reliable diagnosis possible and easy. However, unless apoB is introduced into routine clinical care, type III hyperlipoproteinemia will often not be recognized. Given the cardiovascular risk associated with type III and its responsiveness to treatment, this should not be acceptable.

User experience of instant blood pressure: exploring reasons for the popularity of an inaccurate mobile health app

Instant blood pressure (IBP) is a top-selling yet inaccurate blood pressure (BP)-measuring app that underreports elevated BP. Its iTunes app store user ratings and reviews were generally positive. Whether underreporting of elevated BP improves user experience is unknown. Participants enrolled at five clinics estimated their BP, measured their BP with IBP, then completed a user experience survey. Participants were grouped based on how their IBP BP measurements compared to their estimated BP (IBP Lower, IBP Similar, or IBP Higher). Logistic regressions compared odds of rating "agree" or "strongly agree" on survey questions by group. Most participants enjoyed using the app. In the adjusted model, IBP Higher had significantly lower proportions reporting enjoyment and motivation to check BP in the future than IBP Similar. All three groups were comparable in perceived accuracy of IBP and most participants perceived it to be accurate. However, user enjoyment and likelihood of future BP monitoring were negatively associated with higher-than-expected reported systolic BP. These data suggest reassuring app results from an inaccurate BP-measuring app may have improved user experience, which may have led to more positive user reviews and greater sales. Systematic underreporting of elevated BPs may have been a contributor to the app's success. Further studies are needed to confirm whether falsely reassuring output from other mobile health apps improve user experience and drives uptake.

Harnessing mHealth technologies to increase physical activity and prevent cardiovascular disease

Research into prevention of cardiovascular disease has increasingly focused on mobile health (mHealth) technologies and their efficacy in helping individuals adhere to heart-healthy recommendations, including daily physical activity levels. By including the use of mHealth technologies in the discussion of physical activity recommendations, clinicians empower patients to play an active daily role in modifying their cardiovascular risk-factor profile. In this review, we critically evaluate the mHealth and physical activity literature to determine how these tools may lower cardiovascular risk while providing real-time tracking, feedback, and motivation on physical activity levels. We analyze the various domains-including user knowledge, social support, behavioral change theory, and self-motivation-that potentially influence the effectiveness of smartphone applications to impact individual physical activity levels. In doing so, we hope to provide a thorough overview of the mHealth landscape, in addition to highlighting many of the administrative, reimbursement, and patient-privacy challenges of using these technologies in patient care. Finally, we propose a behavioral change model and checklist for clinicians to assist patients in utilizing mHealth technology to best achieve meaningful changes in daily physical activity levels.

Evaluation of α-tubulin, detyrosinated α-tubulin, and vimentin in CTCs: identification of the interaction between CTCs and blood cells through cytoskeletal elements

Background

Circulating tumor cells (CTCs) are the major players in the metastatic process. A potential mechanism of cell migration and invasion is the formation of microtentacles in tumor cells. These structures are supported by α-tubulin (TUB), detyrosinated α-tubulin (GLU), and vimentin (VIM). In the current study, we evaluated the expression of those cytoskeletal proteins in CTCs.

Methods

Forty patients with breast cancer (BC) (16 early and 24 metastatic) were enrolled in the study. CTCs were isolated using the ISET platform and stained with the following combinations of antibodies: pancytokeratin (CK)/VIM/TUB and CK/VIM/GLU. Samples were analyzed with the ARIOL platform and confocal laser scanning microscopy.

Results

Fluorescence quantification revealed that the ratios CK/TUB, CK/VIM, and CK/GLU were statistically increased in MCF7 compared with more aggressive cell lines (SKBR3 and MDA-MB-231). In addition, all of these ratios were statistically increased in MCF7 cells compared with metastatic BC patients’ CTCs (p = 0.0001, p = 0.0001, and p = 0.003, respectively). Interestingly, intercellular connections among CTCs and between CTCs and blood cells through cytoskeleton bridges were revealed, whereas microtentacles were increased in patients with CTC clusters. These intercellular connections were supported by TUB, VIM, and GLU. Quantification of the examined molecules revealed that the median intensity of TUB, GLU, and VIM was significantly increased in patients with metastatic BC compared with those with early disease (TUB, 62.27 vs 11.5, p = 0.0001; GLU, 6.99 vs 5.29, p = 0.029; and VIM, 8.24 vs 5.38, p = 0.0001, respectively).

Conclusions

CTCs from patients with BC aggregate to each other and to blood cells through cytoskeletal protrusions, supported by VIM, TUB, and GLU. Quantification of these molecules could potentially identify CTCs related to more aggressive disease.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-0993-z) contains supplementary material, which is available to authorized users.

Novel Therapeutic Targets for Managing Dyslipidemia

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of morbidity and mortality in developed nations. Therapeutic modulation of dyslipidemia by inhibiting 3'-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is standard practice throughout the world. However, based on findings from Mendelian studies and genetic sequencing in prospective longitudinal cohorts from around the world, novel therapeutic targets regulating lipid and lipoprotein metabolism, such as apoprotein C3, angiopoietin-like proteins 3 and 4, and lipoprotein(a), have been identified. These targets may provide additional avenues to prevent and treat atherosclerotic disease. We therefore review these novel molecular targets by addressing available Mendelian and observational data, therapeutic agents in development, and early outcomes results.

Dual-energy CT in patients with abdominal malignant lymphoma: impact of noise-optimised virtual monoenergetic imaging on objective and subjective image quality

AIM

To investigate the impact of noise-optimised virtual monoenergetic imaging (VMI+) reconstructions on quantitative and qualitative image parameters in patients with malignant lymphoma at dual-energy computed tomography (DECT) examinations of the abdomen.

MATERIALS AND METHODS

Thirty-five consecutive patients (mean age, 53.8±18.6 years; range, 21-82 years) with histologically proven malignant lymphoma of the abdomen were included retrospectively. Images were post-processed with standard linear blending (M_0.6), traditional VMI, and VMI+ technique at energy levels ranging from 40 to 100 keV in 10 keV increments. Signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were objectively measured in lymphoma lesions. Image quality, lesion delineation, and image noise were rated subjectively by three blinded observers using five-point Likert scales.

RESULTS

Quantitative image quality parameters peaked at 40-keV VMI+ (SNR, 15.77±7.74; CNR, 18.27±8.04) with significant differences compared to standard linearly blended M_0.6 (SNR, 7.96±3.26; CNR, 13.55±3.47) and all traditional VMI series (p<0.001). Qualitative image quality assessment revealed significantly superior ratings for image quality at 60-keV VMI+ (median, 5) in comparison with all other image series (p<0.001). Assessment of lesion delineation showed the highest rating scores for 40-keV VMI+ series (median, 5), while lowest subjective image noise was found for 100-keV VMI+ reconstructions (median, 5).

CONCLUSION

Low-keV VMI+ reconstructions led to improved image quality and lesion delineation of malignant lymphoma lesions compared to standard image reconstruction and traditional VMI at abdominal DECT examinations.

Hypertriglyceridemia and cardiovascular risk: a cautionary note about metabolic confounding

Triglycerides are the conventional tool to measure VLDLs, whereas LDL cholesterol (LDL-C) is the conventional tool to measure LDLs. Multiple epidemiological studies, including a series of genetically based analyses, have demonstrated that cardiovascular risk is related to triglycerides independently of LDL-C, and this has led to a series of new therapeutic agents designed specifically to reduce plasma triglycerides. The triglyceride hypothesis posits that increased levels of triglycerides increase cardiovascular risk and decreasing plasma triglycerides decreases cardiovascular risk. In this work, we will examine the validity of the triglyceride hypothesis by detailing the biological complexities associated with hypertriglyceridemia, the genetic epidemiological evidence in favor of hypertriglyceridemia, the evidence from the fibrate randomized clinical trials relating triglycerides and clinical outcomes, and the completeness of the evidence from the initial studies of novel mutations and the therapeutic agents based on these mutations that lower triglycerides. Because of the multiple metabolic links between VLDL and LDL, we will try to demonstrate that measuring triglycerides and LDL-C alone are inadequate to document the lipoprotein profile. We will try to demonstrate that apoB must be measured, as well as triglycerides and cholesterol, to have an accurate estimate of lipoprotein status.

mActive-Smoke: A Prospective Observational Study Using Mobile Health Tools to Assess the Association of Physical Activity With Smoking Urges

BACKGROUND

Evidence that physical activity can curb smoking urges is limited in scope to acute effects and largely reliant on retrospective self-reported measures. Mobile health technologies offer novel mechanisms for capturing real-time data of behaviors in the natural environment.

OBJECTIVE

This study aimed to explore this in a real-world longitudinal setting by leveraging mobile health tools to assess the association between objectively measured physical activity and concurrent smoking urges in a 12-week prospective observational study.

METHODS

We enrolled 60 active smokers (≥3 cigarettes per day) and recorded baseline demographics, physical activity, and smoking behaviors using a Web-based questionnaire. Step counts were measured continuously using the Fitbit Charge HR. Participants reported instantaneous smoking urges via text message using a Likert scale ranging from 1 to 9. On study completion, participants reported follow-up smoking behaviors in an online exit survey.

RESULTS

A total of 53 participants (aged 40 [SD 12] years, 57% [30/53] women, 49% [26/53] nonwhite) recorded at least 6 weeks of data and were thus included in the analysis. We recorded 15,365 urge messages throughout the study, with a mean of 290 (SD 62) messages per participant. Mean urge over the course of the study was positively associated with daily cigarette consumption at follow-up (Pearson r=.33; P=.02). No association existed between daily steps and mean daily urge (beta=-6.95×10^-3 per 1000 steps; P=.30). Regression models of acute effects, however, did reveal modest inverse associations between steps within 30-, 60-, and 120-min time windows of a reported urge (beta=-.0191 per 100 steps, P<.001). Moreover, 6 individuals (approximately 10% of the study population) exhibited a stronger and consistent inverse association between steps and urge at both the day level (mean individualized beta=-.153 per 1000 steps) and 30-min level (mean individualized beta=-1.66 per 1000 steps).

CONCLUSIONS

Although there was no association between objectively measured daily physical activity and concurrently self-reported smoking urges, there was a modest inverse relationship between recent step counts (30-120 min) and urge. Approximately 10% of the individuals appeared to have a stronger and consistent inverse association between physical activity and urge, a provocative finding warranting further study.

Abstract 422: Association of Remnant Lipoprotein Cholesterol and Levels of Glucose and Insulin: the Very Large Database of Lipids

Background: A defining feature of diabetic dyslipidemia is elevation of triglyceride-rich lipoproteins, particularly remnant lipoprotein cholesterol (RLP-C). Lowering these lipoproteins may reduce risk of atherosclerotic cardiovascular disease in diabetic patients, though the relationship between RLP-C and hyperglycemia as well as hyperinsulinemia remains inadequately characterized. The purpose of this study was to determine the association of RLP-C with serum glucose and insulin across a broad range of insulin resistance.

Methods: We used a sample of individuals from the Very Large Database of Lipids with measured fasting serum glucose and insulin levels, as well as lipoprotein cholesterol levels measured by the Vertical Auto Profile test (Atherotech, Birmingham, AL). RLP-C was defined as the sum of VLDL 3 -C + IDL-C. The study population was divided into deciles of HOMA-IR, calculated as [Insulin х Glucose/405]. We performed multivariable linear regression models to determine associations of RLP-C with insulin and glucose after adjusting for age, sex, real LDL-C, triglycerides, AST, BUN and creatinine. Covariates not normally distributed were log-transformed. Analysis was performed in overall population and across HOMA-IR deciles.

Results: We included a total of 146,826 individuals (43.6% male, mean age 54.9 ± 15.9 years). Median values were: insulin, 9 uU/mL; glucose, 95 mg/dL; RLP-C, 26 mg/dL. The models in our Table explained 60% of variance in RLP-C. Overall, insulin (β=-1.85, p<0.001) and glucose (β=-0.84, p<0.001) had significant negative associations with RLP-C. However, levels of RLP-C were significantly associated with insulin but not glucose across most HOMA-IR deciles (Table).

Conclusion: RLP-C is significantly associated with levels of serum insulin but not with glucose across a spectrum of insulin resistance. Further characterization of the relationship between RLP-C and serum insulin is needed to help guide future therapies for patients with diabetes.

The prevalence and correlates of subclinical atherosclerosis among adults with low-density lipoprotein cholesterol <70 mg/dL: The Multi-Ethnic Study of Atherosclerosis (MESA) and Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

BACKGROUND AND AIMS

The prevalence and correlates of subclinical atherosclerosis when low-density lipoprotein cholesterol (LDL-C) levels are low remain unclear. Therefore, we examined the association of cardiovascular risk factors and subclinical atherosclerosis among individuals with untreated LDL-C <70 mg/dL.

METHODS

We included participants from the Multi-Ethnic Study of Atherosclerosis (MESA) and the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) cohorts. To optimize accuracy, LDL-C was calculated by the validated Martin/Hopkins equation that uses an adjustable factor for the ratio of triglycerides to very low-density lipoprotein cholesterol. We defined subclinical atherosclerosis as a coronary artery calcium (CAC) score >0 in the combined cohort or common carotid intima media thickness (cIMT) in the 4^th quartile, using cohort-specific cIMT distributions at baseline. Logistic regression models examined the cross-sectional associations of cardiovascular risk factors and subclinical atherosclerosis.

RESULTS

Among 9411 participants not on lipid lowering therapy, 263 (3%) had LDL-C <70 mg/dL (MESA: 206, ELSA: 57). Mean age in this population was 58 (SD 12) years, with 43% men, and 41% Black. The prevalence of CAC >0 in those with untreated LDL-C<70 mg/dL was 30%, and 18% were in 4th quartile of cIMT. In demographically adjusted models, only ever smoking was significantly associated with both CAC and cIMT. Similar results were obtained in risk factor-adjusted models (smoking: OR, 2.29; 95% CI, 1.10-4.80 and OR, 3.44; 95% CI, 1.41-8.37 for CAC and cIMT, respectively).

CONCLUSIONS

Among middle-aged to older individuals with untreated LDL-C <70 mg/dL, subclinical atherosclerosis remains moderately common and is associated with cigarette smoking.

The role of mHealth for improving medication adherence in patients with cardiovascular disease: a systematic review

Cardiovascular disease is a leading cause of morbidity and mortality worldwide, and a key barrier to improved outcomes is medication non-adherence. The aim of this study is to review the role of mobile health (mHealth) tools for improving medication adherence in patients with cardiovascular disease. We performed a systematic search for randomized controlled trials that primarily investigated mHealth tools for improving adherence to cardiovascular disease medications in patients with hypertension, coronary artery disease, heart failure, peripheral arterial disease, and stroke. We extracted and reviewed data on the types of mHealth tools used, preferences of patients and healthcare providers, the effect of the mHealth interventions on medication adherence, and the limitations of trials. We identified 10 completed trials matching our selection criteria, mostly with <100 participants, and ranging in duration from 1 to 18 months. mHealth tools included text messages, Bluetooth-enabled electronic pill boxes, online messaging platforms, and interactive voice calls. Patients and healthcare providers generally preferred mHealth to other interventions. All 10 studies reported that mHealth interventions improved medication adherence, though the magnitude of benefit was not consistently large and in one study was not greater than a telehealth comparator. Limitations of trials included small sample sizes, short duration of follow-up, self-reported outcomes, and insufficient assessment of unintended harms and financial implications. Current evidence suggests that mHealth tools can improve medication adherence in patients with cardiovascular diseases. However, high-quality clinical trials of sufficient size and duration are needed to move the field forward and justify use in routine care.

Inflammation and Cardiovascular Disease Risk: A Case Study of HIV and Inflammatory Joint Disease

The epidemiologic data associating infection and inflammation with increased risk of cardiovascular disease is well established. Patients with chronically upregulated inflammatory pathways, such as those with HIV and inflammatory joint diseases, often have a risk of future cardiovascular risk that is similar to or higher than patients with diabetes. Thus, it is of heightened importance for clinicians to consider the cardiovascular risk of patients with these conditions. HIV and inflammatory joint diseases are archetypal examples of how inflammatory disorders contribute to vascular disease and provide illustrative lessons that can be leveraged in the prevention of cardiovascular disease. Managing chronic inflammatory diseases calls for a multifaceted approach to evaluation and treatment of suboptimal lifestyle habits, accurate estimation of cardiovascular disease risk with potential upwards recalibration due to chronic inflammation, and more intensive treatment of risk factors because current tools often underestimate the risk in this population. This approach is further supported by the recently published CANTOS trial demonstrating that reducing inflammation can serve as a therapeutic target among persons with residual inflammatory risk for cardiovascular disease.

Relationship of Lipids and Lipid-Lowering Medications With Cognitive Function: The Multi-Ethnic Study of Atherosclerosis

Studies on the relationship of cholesterol concentrations and lipid-lowering medications with dementia risk have yielded inconsistent findings. Therefore, we investigated the association of lipid concentrations and lipid-lowering medications with cognitive function in the Multi-Ethnic Study of Atherosclerosis across 3 different cognitive domains assessed by means of the Cognitive Abilities Screening Instrument (CASI; version 2), the Digit Symbol Coding (DSC) Test, and the Digit Span (DS) Test in 2010-2012. After adjustment for sociodemographic and confounding factors, including concentrations of other lipids and use of lipid-lowering medication, higher total cholesterol, low-density lipoprotein cholesterol, and non-high-density-lipoprotein cholesterol concentrations were modestly associated with higher DS Test scores. None of the lipid parameters were associated with CASI or DSC Test scores. Similarly, changes in lipid concentrations were not associated with any cognitive function test score. Using treatment effects model analysis and after adjusting for confounding factors, including lipid concentrations, the use of any lipid-lowering medication, especially statins, was associated with higher scores on the CASI and backward DS tests but not on the DSC and forward DS tests. Our study does not support a robust association between lipid concentrations and cognitive function or between the use of lipid-lowering medication, especially statins, and worse cognitive function.

Impact of Novel Low-Density Lipoprotein-Cholesterol Assessment on the Utility of Secondary Non-High-Density Lipoprotein-C and Apolipoprotein B Targets in Selected Worldwide Dyslipidemia Guidelines

BACKGROUND

Selected dyslipidemia guidelines recommend non-high-density lipoprotein-cholesterol (non-HDL-C) and apolipoprotein B (apoB) as secondary targets to the primary target of low-density lipoprotein-cholesterol (LDL-C). After considering 2 LDL-C estimates that differ in accuracy, we examined: (1) how frequently non-HDL-C guideline targets could change management; and (2) the utility of apoB targets after meeting LDL-C and non-HDL-C targets.

METHODS

We analyzed 2518 adults representative of the US population from the 2011 to 2012 National Health and Nutrition Examination Survey and 126 092 patients from the Very Large Database of Lipids study with apoB. We identified all individuals as well as those with high-risk clinical features, including coronary artery disease, diabetes mellitus, and metabolic syndrome who met very high- and high-risk guideline targets of LDL-C <70 and <100 mg/dL using Friedewald estimation (LDL-C_F) and a novel, more accurate method (LDL-C_N). Next, we examined those not meeting non-HDL-C (<100, <130 mg/dL) and apoB (<80, <100 mg/dL) guideline targets. In those meeting dual LDL-C and non-HDL-C targets (<70 and <100 mg/dL, respectively, or <100 and <130 mg/dL, respectively), we determined the proportion of individuals who did not meet guideline apoB targets (<80 or <100 mg/dL).

RESULTS

A total of 7% to 9% and 31% to 36% of individuals had LDL-C <70 and <100 mg/dL, respectively. Among those with LDL-C_F<70 mg/dL, 14% to 15% had non-HDL-C ≥100 mg/dL, and 7% to 8% had apoB ≥80 mg/dL. Among those with LDL-C_F<100 mg/dL, 8% to 10% had non-HDL-C ≥130 mg/dL and 2% to 3% had apoB ≥100 mg/dL. In comparison, among those with LDL-C_N<70 or 100 mg/dL, only ≈2% and ≈1% of individuals, respectively, had non-HDL-C and apoB values above guideline targets. Similar trends were upheld among those with high-risk clinical features: ≈0% to 3% of individuals with LDL-C_N<70 mg/dL had non-HDL-C ≥100 mg/dL or apoB ≥80 mg/dL compared with 13% to 38% and 9% to 25%, respectively, in those with LDL-C_F<70 mg/dL. With LDL-C_F or LDL-C_N<70 mg/dL and non-HDL-C <100 mg/dL, 0% to 1% had apoB ≥80 mg/dL. Among all dual LDL-C_F or LDL-C_N<100 mg/dL and non-HDL-C <130 mg/dL individuals, 0% to 0.4% had apoB ≥100 mg/dL. These findings were robust to sex, fasting status, and lipid-lowering therapy status.

CONCLUSIONS

After more accurately estimating LDL-C, guideline-suggested non-HDL-C targets could alter management in only a small fraction of individuals, including those with coronary artery disease and other high-risk clinical features. Furthermore, current guideline-suggested apoB targets provide modest utility after meeting cholesterol targets.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01698489.

Associations of Lipoprotein(a) Levels With Incident Atrial Fibrillation and Ischemic Stroke: The ARIC (Atherosclerosis Risk in Communities) Study

Background

Lipoprotein(a) (Lp[a]) is proatherosclerotic and prothrombotic, causally related to coronary disease, and associated with other cardiovascular diseases. The association of Lp(a) with incident atrial fibrillation (AF) and with ischemic stroke among individuals with AF remains to be elucidated.

Methods and Results

In the community‐based ARIC (Atherosclerosis Risk in Communities) study cohort, Lp(a) levels were measured by a Denka Seiken assay at visit 4 (1996–1998). We used multivariable‐adjusted Cox models to compare AF and ischemic stroke risk across Lp(a) levels. First, we evaluated incident AF in 9908 participants free of AF at baseline. AF was ascertained by electrocardiography at study visits, hospital International Statistical Classification of Diseases, 9th Revision (ICD‐9) codes, and death certificates. We then evaluated incident ischemic stroke in 10 127 participants free of stroke at baseline. Stroke was identified by annual phone calls, hospital ICD‐9 Revision codes, and death certificates. The baseline age was 62.7±5.6 years. Median Lp(a) levels were 13.3 mg/dL (interquartile range, 5.2–39.7 mg/dL). Median follow‐up was 13.9 and 15.8 years for AF and stroke, respectively. Lp(a) was not associated with incident AF (hazard ratio, 0.98; 95% confidence interval, 0.82–1.17), comparing those with Lp(a) ≥50 with those with Lp(a) <10 mg/dL. High Lp(a) was associated with a 42% relative increase in stroke risk among participants without AF (hazard ratio, 1.42; 95% confidence interval, 1.07–1.90) but not in those with AF (hazard ratio, 1.06; 95% confidence interval, 0.70–1.61 [P interaction for AF=0.25]). There were no interactions by race or sex. No association was found for cardioembolic stroke subtype.

Conclusions

High Lp(a) levels were not associated with incident AF. Lp(a) levels were associated with increased ischemic stroke risk, primarily among individuals without AF but not in those with AF.