Low-density Lipoprotein Cholesterol Testing Research Articles

LOGAN-CV: A Prospective Study of a Multifaceted Intervention Targeting United States Clinicians to Improve Guideline-Based Management of Lipid-Lowering Therapy.

The 2018 American Heart Association (AHA)/American College of Cardiology (ACC)/Multisociety blood cholesterol guidelines recommend clinicians consider adding non-statin therapy for patients with very high-risk (VHR) atherosclerotic cardiovascular disease (ASCVD) and low-density lipoprotein cholesterol (LDL-C) ≥ 70mg/dl while receiving maximally tolerated statins. However, according to a recent study, only 17.1% of patients with established ASCVD received appropriate lipid-lowering therapy (LLT) intensification. Here, we describe the design of a prospective, 12-month study (LOGAN-CV) evaluating a multifaceted site-level intervention to enhance clinicians' adherence to guidelines to improve LDL-C levels for patients with VHR ASCVD. Clinicians from up to ten research sites are eligible if they care for adult patients with ASCVD. Interventions include educational modules, a cloud-based performance platform providing clinicians a tailored summary of their LDL-C management performance, newsletters, periodic peer-to-peer calls, and pre- and post-intervention surveys evaluating knowledge, attitudes, and beliefs around LDL-C management, with additional interventions for clinicians demonstrating a lower readiness to make treatment decisions based on guideline recommendations. Patients with VHR ASCVD, defined as having recent myocardial infarction and LDL-C ≥ 70mg/dl despite statin treatment, will be included in the study. Patient data will be collected from electronic medical records from baseline (clinician enrollment) through the 12-month intervention. The study started in October 2022, with anticipated completion in March 2024. The change in proportion of patients with LDL-C < 70mg/dl achieved at any time during the 12-month intervention (primary); LLT intensification, changes in guideline-aligned LDL-C testing and LLT titration over 12months, and change in overall clinicians' knowledge, attitudes, and beliefsare key outcomes of interest. The LOGAN-CV study addresses a critical unmet need in LDL-C control in patients with VHR ASCVD and evaluates the effect of a multifaceted intervention targeting clinicians to improve their adherence to guidelines and consequently improve clinical outcomes for patients.

Abstract 14678: Racial/Ethnic Disparities in Low-Density Lipoprotein Cholesterol Testing Following Myocardial Infarction Hospitalization Among Medicare Beneficiaries in the United States, by State

Introduction: Low-density lipoprotein cholesterol (LDL-C) is used to guide lipid-lowering treatment following hospitalization for myocardial infarction (MI). Recent analyses illustrate a lack of short-term LDL-C testing across the United States, but it is unclear whether race/ethnicity differences exist in all states. Lack of LDL-C testing following an MI may represent a missed opportunity to identify groups of patients with low response to lipid-lowering therapy. Research Question: Does use of LDL-C testing at 90 days post-MI differ by race in each state and across states? Methods: We conducted a retrospective cohort study of Medicare beneficiaries with fee-for-service coverage, pharmacy benefits, and ≥66 years of age with an MI hospitalization between 2016 and 2020 and estimated the cumulative incidence of LDL-C testing at 90 days post-MI overall, by state, and by race. Results: Of the 532,767 MI hospitalizations, 84.4% and 8.4% were among non-Hispanic White and non-Hispanic Black beneficiaries, respectively, with Asian and Hispanic beneficiaries each representing 2.0% of the hospitalizations. The cumulative incidence of LDL-C testing in the US was 29.9%. Hawaii had the highest overall cumulative incidence of LDL-C testing (43%) while Arkansas had the lowest (17%). Cumulative incidence of LDL-C testing was lowest among non-Hispanic Blacks (26.0%) compared to all other racial groups with testing rates between 30-33%. In most states, cumulative incidence of LDL-C testing among Non-Hispanic Blacks was lower than the state average, whereas among Whites it was higher than the state average (see Table 1). Conclusions: LDL-C testing was low in the 90 days after hospital discharge for MI among Medicare beneficiaries, with substantial geographic and race disparities. In many states, our data suggests testing for Black Americans was lower than the state average. Funding: Amgen Inc.

Achievement Rates for Low-Density Lipoprotein Cholesterol Goals in Patients at High Risk of Atherosclerotic Cardiovascular Disease in a Real-World Setting in Japan.

The study aimed to investigate low-density lipoprotein cholesterol (LDL-C) goal achievement rates in patients receiving LDL-C-lowering therapy using recent real-world data, following the 2017 revision of the Japan Atherosclerosis Society Guidelines for Prevention of Atherosclerotic Cardiovascular Diseases (JAS GL2017). Patients with documented LDL-C test results were extracted from the Medical Data Vision claims database between July 2018 and June 2021 and divided into three groups according to JAS GL2017: primary prevention high risk (Group I, LDL-C goal ＜120 mg/dL), secondary prevention (Group II, LDL-C goal ＜100 mg/dL), and secondary prevention high risk (Group III, LDL-C goal ＜70 mg/dL). The mean LDL-C value was 108.7 mg/dL (n=125,235), 94.4 mg/dL (n=57,910), and 90.6 mg/dL (n=33,850) in Groups I, II, and III, respectively. Intensive statin monotherapy (pitavastatin, rosuvastatin, or atorvastatin) was the most frequently prescribed lipid-lowering treatment (21.6%, 30.8%, and 42.7% in Groups I, II, and III, respectively), followed by ezetimibe (2.5%, 7.1%, and 8.5% in Groups I, II, and III, respectively). LDL-C goals were achieved by 65.5%, 60.6%, and 25.4% of patients overall in Groups I, II, and III, respectively. Achievement rates were 83.9%, 75.3%, and 29.5% in patients prescribed intensive statin monotherapy and 82.3%, 86.4%, and 46.4% in those prescribed statin and ezetimibe combinations in Groups I, II, and III, respectively. In Group III, the proportion of patients with familial hypercholesterolemia prescribed statin and ezetimibe combinations achieving LDL-C goals was low (32.5%). The proportion of patients achieving LDL-C goals for secondary prevention in the high-risk group remains low even with statin and ezetimibe combination therapy.

Concordance between low density lipoprotein cholesterol concentration measurement by enzymatic method and calculation by Friedewald formula in cardiovascular risk classification

Accurate estimation of low-density lipoprotein cholesterol (LDL-C) is important for cardiovascular risk assessment and guiding cholesterol-lowering therapy. Due to the high cost of β-quantification (Gold standard) and time-consuming, direct measurement of LDL-C is an alternative method. However, unlike the calculation of LDL-C by Friedewald formula, there is an additional cost in terms of reagents for performing a direct LDL-C test. The current study aimed to compare direct LDL-C concentration determination to data calculated by Friedewald formula. 752 lipid profiles of 710 people with LDL-C estimated by direct LDL assay, in the Biochemistry laboratory of university hospital center of Angré, were included in the study. In the same group, LDL-C was calculated using Friedewald formula. Lin’s concordance correlation coefficient (ccc) and Passing-Bablok regression analysis using, MedCal software, were performed to assess the strength of concordance between the 2 methods, and identify any possible bias. The concordance between the two methods was moderate (ρc = 0.9466). Passing-Bablok regression analysis revealed a systematic bias between the two methods. The total error observed (TEobs) between the two methods was higher than allowable total error recommended by the NCEP-ATPIII when LDL-C values was less than 159 mg/dL (4.112 mmol/L). The Friedewald formula resulted in lower LDL-C concentration values. Despite its cost-effectiveness in the estimation of LDL-C, an underestimation of LDL-C levels could result in inaccurate cardiovascular diseases (CVD) risk assessments and potentially significant future societal costs due to inadequate prevention and treatment of CVD.

Contemporary patterns of lipoprotein(a) testing and associated clinical care and outcomes

ObjectiveElevated lipoprotein(a) [Lp(a)] is associated with atherosclerotic cardiovascular disease, yet little is known about Lp(a) testing patterns in real-world practice. The objective of this analysis was to determine how Lp(a) testing is used in clinical practice in comparison with low density lipoprotein cholesterol (LDL-C) testing alone, and to determine whether elevated Lp(a) level is associated with subsequent initiation of lipid-lowering therapy (LLT) and incident cardiovascular (CV) events. MethodsThis is an observational cohort study, based on lab tests administered between Jan 1, 2015 and Dec 31, 2019. We used electronic health record (EHR) data from 11 United States health systems participating in the National Patient-Centered Clinical Research Network (PCORnet). We created two cohorts for comparison: 1) the Lp(a) cohort, of adults with an Lp(a) test and 2) the LDL-C cohort, of 4:1 date- and site-matched adults with an LDL-C test, but no Lp(a) test. The primary exposure was the presence of an Lp(a) or LDL-C test result. In the Lp(a) cohort, we used logistic regression to assess the relationship between Lp(a) results in mass units (< 50, 50-100, and > 100mg/dL) and molar units (<125, 125-250, > 250nmol/L) and initiation of LLT within 3 months. We used multivariable adjusted Cox proportional hazards regression to evaluate these Lp(a) levels and time to composite CV hospitalization, including hospitalization for myocardial infarction, revascularization and ischemic stroke. ResultsOverall, 20,551 patients had Lp(a) test results and 2,584,773 patients had LDL-C test results (82,204 included in the matched LDL-C cohort). Compared with the LDL-C cohort, the Lp(a) cohort more frequently had prevalent ASCVD (24.3% vs. 8.5%) and multiple prior CV events (8.6% vs. 2.6%). Elevated Lp(a) was associated with greater odds of subsequent LLT initiation. Elevated Lp(a) reported in mass units was also associated with subsequent composite CV hospitalization [aHR (95% CI): Lp(a) 50-100mg/dL 1.25 (1.02-1.53), p<0.03, Lp(a) > 100mg/dL 1.23 (1.08-1.40), p<0.01]. ConclusionLp(a) testing is relatively infrequent in health systems across the U.S. As new therapies for Lp(a) emerge, improved patient and provider education is needed to increase awareness of the utility of this risk marker.

Low-density lipoprotein cholesterol, statin therapy, and cerebral microbleeds: The CIRCLE study

BackgroundCurrent evidence suggests a potential association between cerebral microbleeds (CMBs), low-density lipoprotein cholesterol (LDL-C) levels, and statin use, but the exact relationship remains unclear. This study aims to prospectively examine these relationships in a stroke-free population. MethodsFrom January 2010 to January 2020, we enrolled stroke-free individuals with at least one cerebral small vessel disease imaging marker from the CIRCLE study (ClinicalTrials.gov ID: NCT03542734). Participants underwent baseline and 1-year follow-up susceptibility-weighted imaging (SWI), and baseline LDL-C testing. New CMBs were categorized as strictly lobar and deep CMBs based on location. ResultsA total of 209 individuals were included. Baseline serum LDL-C levels were divided into quartiles: Q1 (≤1.76 mmol/L), Q2 (1.77–2.36 mmol/L), Q3 (2.37–2.93 mmol/L), and Q4 (>2.93 mmol/L). The incidence of new deep CMBs was 30.0%, 11.1%, 10.9%, 8.2% in Q1, Q2, Q3, Q4, respectively. Multivariate logistic model revealed that only LDL-C in Q1 was associated with increased incidence of new deep CMBs (OR = 4.256; 95% CI: 1.156–15.666; p = 0.029). In a subset of 169 participants without prior statin use, the use of atorvastatin was associated with reduced occurrence of new deep CMBs (OR = 0.181; 95% CI: 0.035–0.928; p = 0.040), while it was not found with rosuvastatin (OR = 0.808; 95% CI: 0.174–3.741; p = 0.785). ConclusionsWhile lower LDL-C levels were associated with higher CMB development, statin therapy did not increase the risk of new CMBs. Atorvastatin even demonstrated a protective effect.

Lipid Testing Trends Before and After Hospitalization for Myocardial Infarction Among Adults in the United States, 2008-2019.

BackgroundRoutine monitoring of low-density lipoprotein cholesterol (LDL-C) identifies patients who may benefit from modifying lipid-lowering therapies (LLT). However, the extent to which LDL-C testing is occurring in clinical practice is unclear, specifically among patients hospitalized for a myocardial infarction (MI).MethodsUsing US commercial claims data, we identified patients with an incident MI hospitalization between 01/01/2008-03/31/2019. LDL-C testing was assessed in the year before admission (pre-MI) and the year after discharge (post-MI). Changes in LDL-C testing were evaluated using a Poisson model fit to pre-MI rates and extrapolated to the post-MI period. We predicted LDL-C testing rates if no MI had occurred (ie, based on pre-MI trends) and estimated rate differences and ratios (contrasting observed vs predicted rates).ResultsOverall, 389,367 patients were hospitalized for their first MI during the study period. In the month following discharge, 9% received LDL-C testing, increasing to 27% at 3 months and 52% at 12 months. Mean rates (tests per 1000 patients per month) in the pre- and post-MI periods were 51.9 (95% CI: 51.7, 52.1) and 84.4 (95% CI: 84.1, 84.6), respectively. Over 12 months post-MI, observed rates were higher than predicted rates; the maximum rate difference was 66 tests per 1000 patients in month 2 (rate ratio 2.2), stabilizing at a difference of 15–20 (ratio 1.2–1.3) for months 6–12.ConclusionAlthough LDL-C testing increased following MI hospitalization, rates remained lower than recommended by clinical guidelines. This highlights a potential gap in care, where increased LDL-C testing after MI may provide opportunities for LLT modification and decrease risk of subsequent cardiovascular events.

Care gaps in achieving cholesterol targets in people with diabetes: A population-based study in a universal health care setting

AimsStatins are first line therapy in people with diabetes. Little is known about real-world statin intensity use and low-density lipoprotein cholesterol (LDL-C) levels achieved. We aimed to describe statin intensity used, achievement of LDL-C targets, and factors associated with achieving targets among adults with diabetes. MethodsThis population based (∼4.3 million), retrospective observational study, used clinical and administrative databases. Statin use by intensity, adherence, and achievement of LDL-C targets in adults with diabetes were described. Multiple logistic regression assessed the factors associated with achieving targets. ResultsOut of 331,312 individuals with diabetes, 88% had an index LDL-C test. At follow up, 31% overall did not achieve LDL-C targets and overall adherence was 66%. Failure to achieve targets was 49%, 30%, and 25% in low-, moderate-, and high-intensity statin groups, respectively. Those who were older, males, had a history of myocardial infarction, stroke, congestive heart failure, renal disease, better adherence, and higher intensity statin users were more likely to achieve targets. ConclusionsOne-third of people on statins did not achieve targets. Strategies to fill the gap between ideal and current levels of LDL-C achieved are needed if the benefits of statins demonstrated in trials are to be translated into practice.

Association of Low-Density Lipoprotein Testing After an Atherosclerotic Cardiovascular Event with Subsequent Statin Adherence and Intensification

PurposeThis study aimed to evaluate associations between outpatient low-density lipoprotein cholesterol (LDL-C) testing and subsequent statin adherence and intensification in patients after an atherosclerotic cardiovascular (ASCVD) event. MethodsThis was a longitudinal study of adult members of Kaiser Permanente Northern California hospitalized with an ASCVD event (myocardial infarction or stroke) during January 01, 2016, to December 31, 2017, with follow-up through December 31, 2019. Outcomes were statin adherence (estimated using continuous medication gap [CMG]) and intensification (defined by an increased dose or switch to a higher-intensity statin) based on pharmacy dispensing. The exposure of interest was first outpatient LDL-C test after an ASCVD event. Baseline for follow-up was LDL-C test date or a date assigned using incidence density sampling. Multivariate logistic regression models were specified to estimate the odds ratios for statin adherence or intensification among those with vs without an LDL-C test, with adjustment for age, sex, race/ethnicity, smoking, hypertension, diabetes, body mass index, and estimated glomerular filtration rate. ResultsThere were 19,604 adults hospitalized with ASCVD, including 7054 adults not on high-intensity statins. The mean age was 69.5 years and 33.0% were female. Prevalence of good adherence (continuous medication gap ≤20%) was significantly higher (80.2% vs 75.9%; odds ratio 1.38; 95% confidence interval, 1.28-1.49; P <.001) among participants who had an LDL-C test compared with participants who did not. LDL-C testing was associated with significantly higher rates of treatment intensification (16.1% vs 10.7%; odds ratio 1.51; 95% confidence interval,1.29-1.76; P <0.001). ConclusionsLow-density lipoprotein cholesterol testing is recommended for patients with a history of ASCVD and may be a high-value and low-cost intervention to improve adherence and statin management.

Lipid testing trends before and after hospitalization for myocardial infarction among adults in the U.S., 2008–2019

Abstract Background Routine monitoring of low-density lipoprotein cholesterol (LDL-C) identifies patients who are candidates for initiation of lipid-lowering therapies (LLT), assesses adherence and response, and measures clinical indications for modifications to treatment. This study investigated LDL-C testing trends among patients hospitalized for incident myocardial infarction (MI), a population at high risk of future atherosclerotic cardiovascular disease (ASCVD) events who may benefit from additional LLT. Purpose Our objective was to estimate rates of LDL-C testing before and after MI hospitalization, hypothesizing that testing rates would increase following MI. Methods Using claims data from a large population with Medicare supplemental or commercial insurance, we identified U.S. adults aged ≥20 years discharged from a MI hospitalization. Patients qualified for the study cohort if their first MI hospitalization occurred during 1/1/2008–3/31/2019, with one year of continuous enrolment in insurance leading up to the hospitalization. Patients were required to be discharged alive to the community (excluded if died or transferred to another facility). LDL-C testing was assessed in the year before admission (pre-MI) and for up to one year after discharge (post-MI), with censoring due to insurance plan disenrollment. To evaluate changes in LDL-C testing, we fit an overdispersed Poisson model to the time-series of pre-MI rates and extrapolated the model to the post-MI period, accounting for person-time and seasonality. We predicted the LDL-C testing rates if no MI occurred (i.e., based only on pre-MI testing trends) and estimated rate differences with 95% confidence intervals (contrasting observed vs. model-predicted rates). Results A total of 389,367 patients were hospitalized for their first MI during the study period with 60% aged &amp;lt;65 years, 64% were male, and 51% filled a statin prescription after discharge (half being high-intensity statins). In the year pre-MI, 25% had a history of diabetes mellitus, 35% used statins, and 4% used ezetimibe. In the year post-MI, only 52% had an LDL-C test. Mean observed rates (tests per 1,000 patients per month) in the pre- and post-MI periods were 51.9 (95% CI: 51.7, 52.1) and 84.4 (95% CI: 84.1, 84.6), respectively. Across the 12 months post-MI, observed rates were higher than model-predicted rates, with the magnitude of rate differences changing over time (Figure). The observed testing rate peaked two months post-MI (rate difference: 65.7, 95% CI: 64.6, 66.7). Conclusions Our findings indicate that LDL-C testing rates increased following a MI hospitalization and stayed elevated throughout the following year. Despite this increase, overall rates remained low, with only one in two patients receiving an LDL-C test in the year after MI. These results highlight a potential gap in care, particularly given the importance of LDL-C monitoring for this population to reduce risk of future ASCVD events. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): This study was funded by Amgen, Inc. Several authors are employees and own stock in Amgen.

COVID-19 PANDEMIC INDUCED DISRUPTIONS IN TROPONIN AND LOW-DENSITY LIPOPROTEIN CHOLESTEROL LABORATORY TEST VOLUMES ACROSS ALBERTA

BACKGROUNDAtherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality in Canada and worldwide. Laboratory tests, including troponin and low-density lipoprotein cholesterol (LDL-C), are important biomarkers of ASCVD risk. The objective of this study was to investigate patterns of testing for troponin and LDL-C test volumes among Alberta residents during the coronavirus disease 2019 (COVID-19) pandemic.METHODS AND RESULTSA repeated cross-sectional study design captured population-level laboratory test volumes between March 15, 2019 and December 14, 2020. Three-month cross-sections were derived to report laboratory test volumes by different COVID-19 restriction periods during 2020-2021 and using 2019-2020 as a preceding control period. Percent change for troponin and LDL-C test volumes were calculated for both control and COVID-19 periods among adult (≥18 years of age) Alberta residents, and stratified by age (18-49, 50-65, 66-79, and ≥80 years), sex, and geographic zones (urban, rural). This preliminary data is part of an ongoing study for which further troponin and LDL-C test volumes will be available up until March 14, 2021 (representing one year of data throughout the COVID-19 pandemic). Among the Alberta population, 292,836 troponin and 794,789 LDL-C tests were captured between March 15, 2020 and December 14, 2020 (Figure 1). Testing patterns during the COVID-19 restriction period showed marked reduction in test volumes from the previous year. The initial cross-section of the COVID-19 period (March-June 2020) was characterized by the largest overall reduction with troponin test volumes decreasing 18% and LDL-C test volumes decreasing 63%, compared to the year prior. As restrictions eased in the summer months of 2020, testing volumes rebounded to near pre-pandemic volumes for both tests. However, in the fall of 2020, troponin tests decreased again (-15%). Within these drops in utilization, slightly larger relative declines were observed for troponin test volumes in women (-20%) and patients ≥80 years-old (-25%) and for LDL-C test volumes among urban residents (-64%), women (-67%) and patients aged 18-49 (-66%) and 50-65 (-65%) years (Table 1).CONCLUSIONThis study describes declines in troponin and LDL-C test volumes in the initial and second COVID-19 lockdown periods. Women had overall smaller total troponin and LDL-C test volumes and larger relative declines during the pandemic compared to men. The decrease in these ASCVD-related laboratory test volumes during the pandemic may have been accompanied by other important changes in indicators of healthcare utilization and associated clinical outcomes. Ongoing analyses will further explore the impact of the pandemic.

Geographic variations in lipid-lowering therapy utilization, LDL-C levels, and proportion retrospectively meeting the ACC/AHA very high-risk criteria in a real-world population of patients with major atherosclerotic cardiovascular disease events in the United States

ObjectiveWe assessed national- and state-level geographic variations among patients with a history of ≥1 major atherosclerotic cardiovascular disease (ASCVD) event in: (1) the proportion of patients with retrospectively identified 2018 American College of Cardiology/American Heart Association guideline very high-risk (VHR) ASCVD criteria; (2) utilization of guideline-directed lipid-lowering therapy (LLT); and (3) the proportion of patients with persistent low-density lipoprotein cholesterol (LDL-C) elevations despite statin and/or ezetimibe use. MethodsA retrospective cohort study using the Prognos LDL-C database linked to IQVIA longitudinal medical and prescription claims databases. The study period was from January 01, 2011, to November 30, 2019 and the index period was from January 01, 2016, to November 30, 2019; the index date was defined as the most recent LDL-C test during the index period. The study included patients aged ≥18 years at index who had a measured LDL-C level during the index period and had ≥1 inpatient/outpatient claim for ASCVD during the 5-year pre-index period. ResultsOf patients with any ASCVD (N=4652,468), 1537,514 (33.1%) patients had ≥1 major ASCVD event. Among patients with ≥1 major ASCVD event, the VHR ASCVD criteria were retrospectively identified in 1139,018 (74.1%) patients; Hawaii had the highest (81.7%) and Colorado the lowest (65.0%) proportion of these patients. Nationally, 48.8% and 50.2% of patients with ≥1 major ASCVD event and retrospectively identified VHR ASCVD criteria, respectively, had current LLT use; Massachusetts and Colorado had the highest and lowest proportions, respectively. After standardizing for age and sex, 57.3% and 58.8% of patients with ≥1 major ASCVD event and retrospectively identified VHR ASCVD criteria, respectively, had LDL-C ≥70 mg/dL (≥1.8 mmol/L) despite statin and/or ezetimibe use, with substantial state-level variations observed. ConclusionsThe study highlights high rates of elevated LDL-C and pervasive underuse of LLT in health-insured patients with a history of major ASCVD events treated in the United States, with state-level geographic variations observed.

Low-Density Lipoprotein Cholesterol and Adverse Cardiovascular Events After Percutaneous Coronary Intervention

BackgroundAfter percutaneous coronary interventions (PCIs), patients remain at high risk of developing late cardiovascular events. Although controlling low-density lipoprotein cholesterol (LDL-C) may improve outcomes after PCI, practice guidelines do not have specific recommendations on LDL-C management for this subgroup. ObjectivesThe purpose of this study was to evaluate LDL-C testing and levels after PCIs, and to assess the association between LDL-C and longer-term cardiovascular events after PCIs. MethodsAll patients who received their first PCI from October 1, 2011, to September 30, 2014, in Ontario, Canada, were considered for inclusion. Patients who had LDL-C measurement within 6 months after PCI were categorized as: <70 mg/dl, 70 to <100 mg/dl, and ≥100 mg/dl. The primary composite outcome was cardiovascular death, myocardial infarction, coronary revascularization, and stroke through December 31, 2016. ResultsAmong 47,884 included patients, 52% had LDL-C measured within 6 months of PCI and 57% had LDL-C <70 mg/dl. After a median 3.2 years, the rates of cardiovascular events were 55.2/1,000 person-years for the LDL-C <70 mg/dl group, 60.3/1,000 person-years for 70 to <100 mg/dl, and 94.0/1,000 person-years for ≥100 mg/dl. The adjusted subdistribution hazard ratios for cardiovascular events were 1.17 (95% confidence interval: 1.09 to 1.26) for LDL-C of 70 to <100 mg/dl, and 1.78 (95% confidence interval: 1.64 to 1.94) for LDL-C ≥100 mg/dl when compared with LDL-C <70 mg/dl. ConclusionsOne in 2 patients had LDL-C measured within 6 months after PCI, and only 57% had LDL-C <70 mg/dl. Higher levels of LDL-C were associated with an increased incidence of late cardiovascular events. Improved cholesterol management after PCI should be considered to improve the outcomes of these patients.

Lipid Testing Trends in the US Before and After the Release of the 2013 Cholesterol Treatment Guidelines.

BackgroundThe 2013 ACC/AHA cholesterol treatment guidelines removed the recommendation to treat adults at risk of cardiovascular disease to goal levels of low-density lipoprotein cholesterol (LDL-C). We anticipated that the frequency of LDL-C testing in clinical practice would decline as a result. To test this hypothesis, we evaluated the frequency of LDL-C testing before and after the guideline release.MethodsWe used the MarketScan® Commercial and Medicare Supplemental claims data (1/1/2007–12/31/2016) to identify four cohorts: 1) statin initiators (any intensity), 2) high-intensity statin initiators, 3) ezetimibe initiators, and 4) patients at very high cardiovascular risk (≥2 hospitalizations for myocardial infarction or ischemic stroke, with prevalent statin use). Rates of LDL-C testing by calendar year quarter were estimated for each cohort. To estimate rates in the absence of a guideline change, we fit a time-series model to the pre-guideline rates and extrapolated to the post-guideline period, adjusting for covariates, seasonality, and time trend.ResultsPre- and post-guideline rates (LDL-C tests per 1,000 persons per quarter) were 248 and 235, respectively, for 3.9 million statin initiators; 263 and 246 for 1.3 million high-intensity statin initiators; 277 and 261 for 323,544 ezetimibe initiators; and 180 and 158 for 42,108 very high-risk patients. For all cohorts, observed post-guideline rates were similar to model-predicted rates. On average, the difference between observed and predicted rates was 8.5 for patients initiating any statin; 2.6 for patients initiating a high-intensity statin; 11.4 for patients initiating ezetimibe, and −0.5 for high-risk patients.ConclusionWe observed no discernible impact of the release of the 2013 ACC/AHA guidelines on LDL-C testing rates. Rather, there was a gradual decline in testing rates starting prior to the guideline change and continuing throughout the study period. Our findings suggest that the guidelines had little to no impact on use of LDL-C testing.

Sociodemographic disparities in the management of type 2 diabetes in the United States

Objective To examine the potential sociodemographic disparities in type 2 diabetes (T2D) management and care among US adult individuals, after controlling for clinical and behavioral factors. Methods This was a retrospective cohort study of individuals with T2D (N = 4552) from a linked database of the National Health and Wellness Survey and a large US ambulatory electronic health record (EHR) database. This study period was between 1 January 2015 and 31 December 2018 and individuals were followed up for at least 6 months through EHR after the completion of the survey. The sociodemographic characteristics included gender, race, ethnicity, marital status, education, employment status, household income, insurance status, and geographic region. The independent variables included testing and control of HbA1c, blood pressure (BP), and low-density lipoprotein-cholesterol (LDL-C); hypoglycemia, emergency room (ER) visits, and all-cause hospitalization. Multivariable analyses were conducted using generalized linear models. Results The percentage of uncontrolled HbA1c was 38.6%. With clinical and behavioral characteristics adjusted, individuals living in the Northeast region had 30% higher odds of having HbA1c testing than those who lived in the South. Blacks and Asians were less likely to have HbA1c control than Whites. Uninsured individuals had a lower likelihood of receiving HbA1c, BP, or LDL-C testing compared with commercial insurers. Individuals with low income were more likely to have higher ER visits and hospitalizations. Conclusion Potential sociodemographic disparities exist in T2D management and care in the US, indicating the needs for improvement in healthcare access, educational and behavioral programs, as well as disease and treatment management in these subgroups.

Abstract MP72: Using Non-HDL-C/Triglyceride Ratio To Screen For Direct LDL-C Testing: Improving LDL-C Estimates At A Cost

Introduction: Despite more accurate low-density lipoprotein cholesterol (LDL-C) estimates by the Martin (mLDL-C) method, most laboratories still use the Friedewald (fLDL-C) equation. Low non-high density lipoprotein (non-HDL-C) and high triglycerides (TG) drive inaccuracy in LDL-C estimation. We compared a strategy of identifying errors in fLDL-C using non-HDL-C/TG ratios with subsequent reflex direct LDL-C testing to a strategy of using mLDL-C. Methods: We included 4,939,542 individuals (2/3 derivation, 1/3 validation dataset) with TG &lt;400 mg/dL with lipid profiles directly measured via Vertical Auto Profile from the Very Large Database of Lipids. We compared directly measured LDL-C with estimated fLDL-C and mLDL-C. The direct LDL-C assay has an allowable error of 12% which was used as the threshold for accuracy assessment. LDL-C estimates above and below non-HDL-C/TG cutpoints (range 0-2.0) were evaluated for accuracy from the derivation dataset and the 4 best performing ratios were tested in the validation set. Individuals with non-HDL-C/TG ratios below the cutpoints were assumed to require direct LDL-C measurement. Medicare costs ($17 lipid panel; $12 direct LDL-C) were used to estimate added costs of direct LDL-C measurement. Results: Nearly 8% of fLDL-C results deviated &gt;12% from direct LDL-C compared with only 2.5% of mLDL-C results in the entire population. Non-HDL-C/TG ratios of 0.6-0.9 performed best in the derivation dataset. In the validation dataset, a non-HDL-C/TG ratio of 0.7 had the highest area under the curve for identifying &gt;12% error in fLDL-C estimates (Table). At this ratio, 14.5% of fLDL-C samples would need direct LDL-C measurement at an increase in costs of lipid testing by 10%. Conclusions: Use of non-HDL-C/TG ratio &lt;0.7 as screening for direct LDL-C measurement can improve the accuracy of LDL-C estimates in labs using the Friedewald equation. However, such an approach is significantly costlier than using mLDL-C.

A New Equation for Calculation of Low-Density Lipoprotein Cholesterol in Patients With Normolipidemia and/or Hypertriglyceridemia

Low-density lipoprotein cholesterol (LDL-C), a key cardiovascular disease marker, is often estimated by the Friedewald or Martin equation, but calculating LDL-C is less accurate in patients with a low LDL-C level or hypertriglyceridemia (triglyceride [TG] levels ≥400 mg/dL). To design a more accurate LDL-C equation for patients with a low LDL-C level and/or hypertriglyceridemia. Data on LDL-C levels and other lipid measures from 8656 patients seen at the National Institutes of Health Clinical Center between January 1, 1976, and June 2, 1999, were analyzed by the β-quantification reference method (18 715 LDL-C test results) and were randomly divided into equally sized training and validation data sets. Using TG and non-high-density lipoprotein cholesterol as independent variables, multiple least squares regression was used to develop an equation for very low-density lipoprotein cholesterol, which was then used in a second equation for LDL-C. Equations were tested against the internal validation data set and multiple external data sets of either β-quantification LDL-C results (n = 28 891) or direct LDL-C test results (n = 252 888). Statistical analysis was performed from August 7, 2018, to July 18, 2019. Concordance between calculated and measured LDL-C levels by β-quantification, as assessed by various measures of test accuracy (correlation coefficient [R2], root mean square error [RMSE], mean absolute difference [MAD]), and percentage of patients misclassified at LDL-C treatment thresholds of 70, 100, and 190 mg/dL. Compared with β-quantification, the new equation was more accurate than other LDL-C equations (slope, 0.964; RMSE = 15.2 mg/dL; R2 = 0.9648; vs Friedewald equation: slope, 1.056; RMSE = 32 mg/dL; R2 = 0.8808; vs Martin equation: slope, 0.945; RMSE = 25.7 mg/dL; R2 = 0.9022), particularly for patients with hypertriglyceridemia (MAD = 24.9 mg/dL; vs Friedewald equation: MAD = 56.4 mg/dL; vs Martin equation: MAD = 44.8 mg/dL). The new equation calculates the LDL-C level in patients with TG levels up to 800 mg/dL as accurately as the Friedewald equation does for TG levels less than 400 mg/dL and was associated with 35% fewer misclassifications when patients with hypertriglyceridemia (TG levels, 400-800 mg/dL) were categorized into different LDL-C treatment groups. The new equation can be readily implemented by clinical laboratories with no additional costs compared with the standard lipid panel. It will allow for more accurate calculation of LDL-C level in patients with low LDL-C levels and/or hypertriglyceridemia (TG levels, ≤800 mg/dL) and thus should improve the use of LDL-C level in cardiovascular disease risk management.

Metabolic Monitoring Rates of Youth Treated with Second-Generation Antipsychotics in Usual Care: Results of a Large US National Commercial Health Plan.

Objectives: To examine metabolic monitoring rates in commercially insured children and adolescents treated with a second-generation antipsychotic (SGA) during calendar years (CYs) 2016 and 2017. Methods: In this retrospective study, data were collected from a large national commercial health plan for the period covering January 1, 2016 to December 31, 2017. Commercially insured children and adolescents, aged 8-19 years with ≥2 SGA prescription claims during the CY, were identified for the CY2016 and CY2017 cohorts. The primary outcome of interest was the percentage of subjects with any glucose or lipid metabolism parameter monitoring. Other calculated metabolic testing rates included glucose, hemoglobin A1c (HbA1c), low-density lipoprotein cholesterol (LDL-C), other cholesterol (including triglycerides), and combined glucose and lipid metabolism testing (≥1 test for blood glucose or HbA1c and ≥1 test for LDL-C or other cholesterol). Results: In CY2016 and CY2017, 1502 and 1239 subjects, respectively, were identified for this study. The most common psychiatric diagnoses in CY2016 and CY2017 were major depressive disorder (57.1%, 56.5%, respectively), anxiety disorders (42.9%, 47.5%), attention-deficit/hyperactivity disorder (41.6%, 45.8%), and bipolar disorder (24.1%, 25.9%). The rate of any metabolic testing was 53.5% in CY2016 and 51.3% in CY2017. Glucose testing (50.3%, 46.9%, respectively) was most common in both CYs, followed by LDL-C testing (31.2%, 28.5%). Rates of combined glucose and lipid metabolism testing were 30.7% in CY2016 and 26.9% in CY2017. Conclusions: Given the known potential for adverse cardiometabolic effects, rates of metabolic monitoring associated with SGA use in children and adolescents urgently need to be improved. There is a critical need for understanding barriers to routine monitoring, particularly of lipids, and developing interventions to enhance metabolic monitoring.

Demographic And Clinical Characteristics Of Patients Prescribed Proprotein Convertase Subtilisin/kexin Type 9 Inhibitor Therapy And Patients Whose Current Lipid-Lowering Therapy Was Modified.

PurposeOur objective was to describe the demographic and clinical characteristics of real-world patients in the US with elevated low-density lipoprotein cholesterol (LDL-C) whose lipid-lowering therapy (LLT) ─ both proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor and non-PCSK9 inhibitor ─ was actively modified.MethodsThis retrospective cohort study used linked laboratory (Prognos), pharmacy (IMS Formulary Impact Analyzer), and medical claims (IQVIA Dx/LRx or PharMetrics Plus) data. PCSK9 inhibitor–prescribed patients with LDL-C ≥70 mg/dL (multiply by 0.02586 for mmol/L) at the time of prescription were matched by LDL-C test date to patients whose non-PCSK9 inhibitor therapy was modified by intensifying statin therapy, switching statins without intensification, or augmenting with ezetimibe (N=12,345 in each cohort). Baseline demographics, use of LLT, LDL-C values, atherosclerotic cardiovascular disease (ASCVD) diagnoses and cardiovascular comorbidities, and occurrence of major adverse cardiovascular events (MACE) were assessed during the 2-year pre-index period.ResultsMean age was 66.2 years in the PCSK9 inhibitor cohort and 64.1 years in the cohort whose LLT regimen was otherwise modified. Respectively, mean baseline LDL-C values were 150 and 121 mg/dL; 60.3% and 39.0% of patients had ASCVD diagnoses, and 9.6% and 5.1% had experienced a recent MACE. Prevalence of ASCVD diagnoses in the PCSK9 inhibitor and modified non-PCSK9 inhibitor cohorts, respectively, was 15.5% vs 9.1% for acute coronary syndrome, 20.7% vs 8.7% for coronary revascularization, and 22.2% vs 5.1% for possible familial hypercholesterolemia. In addition, 19.8% of patients in the PCSK9 inhibitor cohort were receiving both statins and ezetimibe vs 5.0% in the modified LLT cohort.ConclusionPhysicians are prescribing PCSK9 inhibitor therapy to patients with markedly elevated LDL-C levels who also have comorbid risk factors for adverse cardiovascular events. These results may be of interest to payers and policymakers involved in devising access strategies for PCSK9 inhibitors.

1482-P: Low-Density Lipoprotein Cholesterol (LDL-C) Management in Patients with Atherosclerotic Cardiovascular Diseases (ASCVD) and Preexisting Diabetes in Alberta, Canada

Background: Lipid-lowering therapy (LLT) reduces the risk of CV events, however, limited real-world data exist on the management of LDL-C in patients with ASCVD and pre-existing diabetes in Canada. Our study describes the clinical characteristics and LDL-C management of patients with ASCVD and diabetes using health system data in Alberta. Methods: A retrospective study was conducted linking multiple health system datasets to examine clinical characteristics and LDL-C levels in those receiving LLT (e.g., statins) after the first LDL-C test. Patients with ASCVD were identified using ICD diagnostic codes between 2011-2015. Similarly, diabetes status was assessed in the year prior to ASCVD diagnosis. LDL-C was assessed at the first (index) and second (follow-up) tests during the study period. LDL-C levels were evaluated based on a threshold of 2.0 mmol/L, as per the 2016 Canadian blood cholesterol management guidelines. Results: Among 144,607 patients with ASCVD and a prescription for LLT (mean age=66.3; 66% male), 27,540 (19.0%) patients were identified with diabetes. Patients with diabetes were more likely to have stroke, myocardial infarction, or peripheral arterial disease. Congestive heart failure and hypertension were found in 26.8% and 87.8% of patients with diabetes compared to 12.5% and 71.5% in those without, respectively. Of the patients with diabetes who had an index and follow-up LDL-C test (n=18,214), 35.0% (n=6,380) did not achieve the guideline specified LDL-C threshold at index. At follow-up (mean=238.9 days after index), 49.0% (n=3,129) of those who did not achieve threshold at index failed to meet the threshold. Conclusions: Nearly half of patients above the LDL-C threshold at the index test did not achieve threshold at the follow-up test, despite receiving LLT. Multifaceted interventions may be required to improve cholesterol management of patients with ASCVD and diabetes in Alberta. Disclosure G. Chen: Consultant; Self; Medlior Health Outcomes Research Ltd. M.S. Farris: Employee; Self; Medlior Health Outcomes Research Ltd. T. Cowling: Stock/Shareholder; Self; Medlior Health Outcomes Research Ltd. M. Tai: Employee; Self; Amgen Inc. L. Pinto: Employee; Self; Amgen Inc. S. Colgan: Employee; Self; Amgen Inc. R. Rogoza: Employee; Self; Amgen Inc. Stock/Shareholder; Self; Amgen Inc. T.J. Anderson: None.