Impact of evidence-based "clinical judgment" on the number of American adults requiring lipid-lowering therapy based on updated NHANES III data. National Health and Nutrition Examination Survey

Primary Prevention Using Cholesterol-Lowering Medications in Patients Meeting New Treatment Guidelines: A Retrospective Cohort Analysis

BACKGROUND

The American College of Cardiology and American Heart Association (ACC/AHA) issued new cholesterol treatment guidelines in 2013. Two of the groups designated for primary prevention were analyzed: patients with a low-density lipoprotein cholesterol (LDL-C) level ≥ 190 mg per dL and diabetic patients aged 40-75 years.

OBJECTIVE

To estimate the effects of primary prevention as specified in the 2013 guidelines on cardiovascular event risk and cost.

METHODS

Primary prevention patients were identified using laboratory and diagnostic data for Humana members from 2007 to 2013. Potential study patients were classified into 3 risk groups: elevated LDL-C, diabetes, and elevated LDL-C and diabetes. Patients receiving cholesterol-lowering medications before their index date were excluded. Eligible patients were divided into 2 treatment groups: (1) primary prevention patients who initiated treatment before experiencing any cardiovascular disease (CVD)-related event, and (2) patients who either did not initiate treatment until after experiencing a CVD event or never initiated treatment. The associations between initiating cholesterol-lowering medications for primary prevention and the risk for acute myocardial infarction, stroke, coronary angioplasty, or coronary artery bypass graft surgery were estimated using Cox proportional hazards models. The effect of primary prevention on health care costs was estimated using generalized linear models.

RESULTS

91,066 patients met study selection criteria. Primary prevention rates were the lowest in diabetic patients (35%), who were newly designated for treatment in the 2013 guidelines. Primary prevention rates were higher for patients designated for treatment under earlier guidelines: 65% for patients with elevated LDL-C and 78% for the combined LDL-C and diabetes group. Primary prevention treatment was associated with significant reductions in cardiovascular event risk (up to 37%) and lower total all-cause costs (by $673) in the first post-index year.

CONCLUSIONS

Initiating cholesterol-lowering medications for primary prevention, as specified in the ACC/AHA 2013 guidelines, for patients with high LDL-C and diabetes is associated with reduced CVD event risks and lower health care costs.

DISCLOSURES

No outside funding supported this study. Han received fellowship support from the Pharmaceutical Research and Manufacturers Association Foundation (PhRMA) during the conduct of this study. Dougherty is employed by PhRMA. The authors have nothing to disclose.

The "New Deadly Quartet" for cardiovascular disease in the 21st century: obesity, metabolic syndrome, inflammation and climate change: how does statin therapy fit into this equation?

Despite population-based improvements in cardiovascular risk factors, such as blood pressure, cholesterol and smoking, cardiovascular disease still remains the number-one cause of mortality in the United States. In 1989, Kaplan coined the term "Deadly Quartet" to represent a combination of risk factors that included upper body obesity, glucose intolerance, hypertriglyceridemia and hypertension [Kaplan in Arch Int Med 7:1514-1520, 1989]. In 2002, the third report of the National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP III) essentially added low HDL-C criteria and renamed this the "metabolic syndrome." [The National Cholesterol Education Program (NCEP) in JAMA 285:2486-2497, 2001] However, often forgotten was that a pro-inflammatory state and pro-thrombotic state were also considered components of the syndrome, albeit the panel did not find enough evidence at the time to recommend routine screening for these risk factors [The National Cholesterol Education Program (NCEP) in JAMA 285:2486-2497, 2001]. Now over a decade later, it may be time to reconsider this deadly quartet by reevaluating the roles of obesity and subclinical inflammation as they relate to the metabolic syndrome. To complete this new quartet, the addition of increased exposure to elevated levels of particulate matter in the atmosphere may help elucidate why this cardiovascular pandemic continues, despite our concerted efforts. In this article, we will summarize the evidence, focusing on how statin therapy may further impact this new version of the "deadly quartet".

Trends in low-density lipoprotein cholesterol goal achievement in high risk United States adults: longitudinal findings from the 1999-2008 National Health and Nutrition Examination Surveys

BACKGROUND

Previous studies have demonstrated gaps in achievement of low-density lipoprotein-cholesterol (LDL-C) goals among U.S. individuals at high cardiovascular disease risk; however, recent studies in selected populations indicate improvements.

OBJECTIVE

We sought to define the longitudinal trends in achieving LDL-C goals among high-risk United States adults from 1999-2008.

METHODS

We analyzed five sequential population-based cross-sectional National Health and Nutrition Examination Surveys 1999-2008, which included 18,656 participants aged 20-79 years. We calculated rates of LDL-C goal achievement and treatment in the high-risk population.

RESULTS

The prevalence of high-risk individuals increased from 13% to 15.5% (p = 0.046). Achievement of LDL-C <100 mg/dL increased from 24% to 50.4% (p<0.0001) in the high-risk population with similar findings in subgroups with (27% to 64.8% p<0.0001) and without (21.8% to 43.7%, p<0.0001) coronary heart disease (CHD). Achievement of LDL-C <70 mg/dL improved from 2.4% to 17% (p<0.0001) in high-risk individuals and subgroups with (3.4% to 21.4%, p<0.0001) and without (1.7% to 14.9%, p<0.0001) CHD. The proportion with LDL-C ≥130 mg/dL and not on lipid medications decreased from 29.4% to 18% (p = 0.0002), with similar findings among CHD (25% to 11.9% p = 0.0013) and non-CHD (35.8% to 20.8% p<0.0001) subgroups.

CONCLUSION

The proportions of the U.S. high-risk population achieving LDL-C <100 mg/dL and <70 mg/dL increased over the last decade. With 65% of the CHD subpopulation achieving an LDL-C <100 mg/dL in the most recent survey, U.S. LDL-C goal achievement exceeds previous reports and approximates rates achieved in highly selected patient cohorts.

Extent of control of cardiovascular risk factors and adherence to recommended therapies in US multiethnic adults with coronary heart disease: from a 2005-2006 national survey

BACKGROUND

Guidelines for cardiovascular risk factor control in people with coronary heart disease (CHD) focus on compliance with beta-adrenoceptor antagonists (beta-blockers), angiotensin receptor blockade (ACE inhibitors/angiotensin II receptor antagonists [angiotensin receptor blockers; ARBs]) [ACE/ARBs], and lipid-lowering agents, with goals for BP of <140/90 mmHg and low-density lipoprotein cholesterol (LDL-C) levels of <2.6 mmol/L (100 mg/dL). Most data derive from registries of hospitalized patients or are from clinical trials. Little data exist on goal attainment and adherence with therapy among CHD survivors of major US ethnic groups in the real-world setting.

OBJECTIVE

We assessed levels of cardiovascular risk factor control and adherence with recommended therapies among US CHD survivors.

METHODS

We identified 364 US adults (representing 12.8 million in the US with CHD) aged 18 years and over in the National Health and Nutrition Examination Survey 2005-6 with known CHD. We calculated proportions of patients who were receiving recommended treatments, and who achieved goal targets for BP, LDL-C levels, glycosylated hemoglobin (HbA(1c)), and nonsmoking status, and differences between actual and goal levels ('distance to goal'), stratified by sex and ethnicity.

RESULTS

Overall, 58%, 38%, and 60% of CHD survivors were receiving beta-adrenoceptor antagonists, ACE/ARBs, and lipid-lowering medications, respectively (22% received all three). However, treatment rates for beta-adrenoceptor antagonists and lipid-lowering agents were lower (p < 0.05 to p < 0.01) in Hispanics (36% and 27%, respectively) and non-Hispanic Blacks (47% and 42%, respectively) than in non-Hispanic Whites. Moreover, lipid-lowering treatment rates were lower in females (50%) than in males (67%) [p < 0.01]. Overall, 78% were nonsmokers while 68% achieved goal levels for BP, 57% for LDL-C levels, and, if diabetic, 67% for HbA(1c). Only 12% met all four goals. Non-Hispanic Whites had the lowest SBP and DBP as well as HbA(1c) (p < 0.05 to p < 0.01 across ethnicity). In those who did not achieve goal levels, distance to goal averaged 1.0 mmol/L (37.0 mg/dL) for LDL-C levels, 15.6 mmHg for SBP, and 1.3% for HbA(1c).

CONCLUSION

Despite clear treatment guidelines, we show that many US adults with CHD, especially Hispanics and non-Hispanic Blacks, are neither receiving recommended treatments nor adequately treated in terms of BP, LDL-C levels, and HbA(1c). Greater efforts by healthcare systems to disseminate and implement guidelines are needed.

Screening for subclinical coronary artery disease measuring carotid intima media thickness

Traditional coronary risk assessment is based on major cardiovascular risk factors using the Framingham risk score. Carotid intima-media thickness (CIMT) measured by ultrasonography is a noninvasive test used to assess for the presence of coronary atherosclerosis. CIMT has been shown to be an independent predictor of future cardiovascular events and is used in research trials as a surrogate for the presence as well as regression of coronary artery disease. The objectives of this report are to review the published reports on CIMT and to help establish the role of CIMT as a screening tool for coronary artery disease in selected patients. CIMT measurement can modify cardiovascular risk prediction in patients initially classified with the Framingham risk score, with reclassification into higher or lower risk categories. It is most useful for refining risk assessment in patients at intermediate risk. The Screening for Heart Attack Prevention and Education (SHAPE) Task Force recommends screening all asymptomatic middle-aged and older men and women using noninvasive imaging. The American Society of Echocardiography established a consensus on the methodologic aspects of CIMT measurement. Sequential scanning of CIMT to assess atherosclerosis is currently not recommended, because of interscan variability and small expected changes over time. In conclusion, in the primary prevention of coronary artery disease, CIMT measurement reclassifies patients into higher or lower risk categories, allowing early appropriate management.

Treating mixed dyslipidemias: why and how

Patients with only mildly elevated low-density lipoprotein cholesterol values but low high-density lipoprotein cholesterol (HDL-C) and/or high triglyceride levels are at high risk for cardiovascular disease. 3-Hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (also known as statins) have been shown to slow coronary heart disease (CHD) progression, reduce CHD events in patients with low HDL-C levels, and raise HDL-C concentrations in patients with mixed dyslipidemias. Some, but not all trials of fibrates have shown benefit in patients with low HDL-C levels. Combination therapy with a statin plus either a fibrate or niacin is effective in improving the entire lipid profile, but may increase cost and side effects.

Newer HMG-CoA reductase inhibitor (statin) therapies

Although most patients can achieve their National Cholesterol Education Program goal with a reduction of < or =30% in low-density lipoprotein cholesterol (LDL-C) levels available with all statins, some patients need greater LDL-C lowering. Furthermore, new study data suggest that greater clinical event reduction may be obtained with more aggressive LDL-C lowering and/or with treatment of factors beyond LDL-C. New formulations of statins. including extended-release preparations, are achieving greater reductions in LDL-C levels as well as favorable modification of high-density lipoprotein cholesterol and triglyceride concentrations while maintaining an excellent safety profile.

National improvements in low-density lipoprotein cholesterol management of individuals at high coronary risk: National Health and Nutrition Examination Survey, 1999 to 2002

BACKGROUND

This study sought to evaluate national levels of elevated low-density lipoprotein cholesterol (LDL-C) before and after publication of the Adult Treatment Panel III (ATP III). The ATP III guidelines intensified LDL-C targets and defined additional high-risk conditions. These recommendations are expected to have a noticeable impact on US cholesterol levels.

METHODS

Coronary heart disease (CHD) risk was determined per ATP III guidelines for US residents aged 20 to 79 years in the 1999 to 2000 and 2001 to 2002 surveys. For those at high risk, the LDL-C mean percentage <100 mg/dL and percentage > or =130 mg/dL, although not taking lipid-lowering therapy, were compared between the 2 surveys. In addition, subsets with and without CHD were evaluated.

RESULTS

Of all high-risk US residents, the mean LDL-C dropped from 129 mg/dL in 1999 to 2000 to 120 mg/dL in 2001 to 2002 (P = .003). Those <100 mg/dL increased from 23% to 32% (P = .003). Those > or =130 mg/dL and not on medication dropped from 36% to 27% (P = .001). Goal achievement and improvements were more favorable in the subset with CHD compared with those at high risk due to high-risk equivalent conditions.

CONCLUSIONS

The sharp increase in high-risk US residents at the goal and the drop in the untreated percentage of those above treatment threshold illustrate national improvements in the management of LDL-C for those at high coronary risk. High-risk subjects without CHD displayed less significant improvements, suggesting an opportunity for better recognition and management of these individuals.

Lipids, lipoproteins and the risk of benign prostatic hyperplasia in community-dwelling men

OBJECTIVE

To examine the associations of serum lipids and lipoproteins with benign prostatic hyperplasia (BPH) in community-dwelling men.

SUBJECTS AND METHODS

This analysis was conducted within the Rancho Bernardo Study, a prospective, community-based cohort study. BPH was defined as a history of prostate surgery for other than cancer, or a medical diagnosis of BPH. Logistic regression modelling, with adjustments for age and stratification by diabetes diagnosis, was used to estimate the odds ratio (OR) of BPH associated with fasting serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, and the triglyceride to HDL ratio.

RESULTS

Among 531 eligible participants, 259 (48%) reported BPH and 272 (52%) reported no BPH. Men with BPH, with a mean (range) age of 75.8 (76.1-80.1) years, were older than men without BPH , at 72.7 (72.4-74.0) years. There were no significant associations of total cholesterol (P trend, 0.52), HDL cholesterol (0.56), triglycerides (0.30), or triglyceride to HDL ratio (0.13) with the risk of BPH. In a subset analysis in men with diabetes, those in the highest tertile (>133 mg/dL) of LDL cholesterol, compared with those in the lowest tertile (<110 mg/dL), were four times more likely to have BPH (odds ratio 4.00, 95% confidence interval 1.27-12.63, P trend 0.02). These results were not explained by the use of statins.

CONCLUSIONS

In these community-dwelling men, higher serum LDL was associated with a greater risk of BPH among diabetics. These data suggest that diabetic men with increased LDL cholesterol are at greater risk of BPH. This observation is consistent with the concept that cardiac risk factors are involved with the pathogenesis of BPH.

Coronary CT Angiography

Owing to ongoing technical refinements and intense scientific and clinical evaluations, computed tomography (CT) of the heart has left the research realm and matured into a clinical application that is about to fulfill its promise to replace invasive cardiac catheterization in selected patient populations. CT coronary angiography is technically more challenging than other CT applications owing to the nature of its target, the continuously moving heart. Rapid technical developments in this field require constant adaptation of acquisition protocols. These challenges, however, are in no way insurmountable for users with knowledge of the general CT technique. The intent of this communication is to provide those interested in and involved with coronary CT angiography with a step-by-step "manual" describing the authors' approach to performing coronary CT angiography. Included are considerations regarding appropriate patient selection, patient medication, radiation protection, contrast enhancement, acquisition and reconstruction parameters, image display and analysis techniques, and the radiology report. The recommendations are based on the authors' experience, which spans the evolution of multi-detector row CT for cardiac applications, from its beginning to the advent of the most current generations of 64-section and dual-source CT technologies, which they believe herald the entrance of this examination into routine clinical practice.

Molecular imaging of inflammation in atherosclerosis with targeted ultrasound detection of vascular cell adhesion molecule-1

BACKGROUND

The ability to image vascular inflammatory responses may allow early diagnosis and treatment of atherosclerosis. We hypothesized that molecular imaging of vascular cell adhesion molecule-1 (VCAM-1) expression with contrast-enhanced ultrasound (CEU) could be used for this purpose.

METHODS AND RESULTS

Attachment of VCAM-1-targeted and control microbubbles to cultured endothelial cells was assessed in a flow chamber at variable shear stress (0.5 to 12.0 dynes/cm2). Microbubble attachment to aortic plaque was determined by en face microscopy of the thoracic aorta 10 minutes after intravenous injection in wild-type or apolipoprotein E-deficient mice on either chow or hypercholesterolemic diet. CEU molecular imaging of the thoracic aorta 10 minutes after intravenous microbubble injection was performed for the same animal groups. VCAM-1-targeted but not control microbubbles attached to cultured endothelial cells, although firm attachment at the highest shear rates (8 to 12 dynes/cm2) occurred only in pulsatile flow conditions. Aortic attachment of microbubbles and targeted CEU signal was very low in control wild-type mice on chow diet. Aortic attachment of microbubbles and CEU signal for VCAM-1-targeted microbubbles differed between treatment groups according to extent of VCAM-1-positive plaque formation (median CEU videointensity, 1.8 [95% CI, 1.2 to 1.7], 3.7 [95% CI, 2.9 to 7.3], 6.8 [95% CI, 3.9 to 7.6], and 11.2 [95% CI, 8.5 to 16.0] for wild-type mice on chow and hypercholesterolemic diet and for apolipoprotein E-deficient mice on chow and hypercholesterolemic diet, respectively; P<0.001).

CONCLUSIONS

CEU molecular imaging of VCAM-1 is capable of rapidly quantifying vascular inflammatory changes that occur in different stages of atherosclerosis. This method may be potentially useful for early risk stratification according to inflammatory phenotype.

Arterial Ultrasonography and Tonometry as Adjuncts to Cardiovascular Risk Stratification

Myocardial infarction and stroke often occur without prior warning in asymptomatic individuals. Identifying individuals at risk is important for cost-effective use of preventive therapies. Algorithms based on risk factors statistically associated with cardiovascular events classify individuals into high-risk, intermediate-risk, or low-risk categories. However, more than one-third of adults in the U.S. are in the intermediate-risk category, and decisions regarding therapy are challenging in this subset. Testing for alterations in arterial function and structure that predate cardiovascular events may help refine cardiovascular risk assessment in the intermediate-risk group and identify candidates for aggressive therapy. Vascular ultrasonography and tonometry are promising test modalities for assessment of arterial function and structure in asymptomatic subjects. Several prospective studies have shown that measures of arterial function and structure provide prognostic information incremental to conventional risk factors. Standardization of methodology and establishment of quality control standards in the performance of these tests could facilitate their integration into clinical practice as adjuncts to existing cardiovascular risk stratification algorithms.

Implications of Cardiac Risk and Low-Density Lipoprotein Cholesterol Distributions in the United States for the Diagnosis and Treatment of Dyslipidemia

Background— Updated guidelines from the National Cholesterol Education Program Adult Treatment Panel III stratify patients into 5 groups of coronary heart disease (CHD) risk that determine intensity of lipid-lowering therapy. The present study assesses the distribution of low-density lipoprotein cholesterol (LDL-C) in the United States across the 5 groups of CHD risk as defined in the updated guidelines.

Methods and Results— Subjects included 7399 individuals 20 to 79 years of age in the 1999 to 2002 National Health and Nutrition Examination Survey representing 171 million individuals in the United States. CHD risk, LDL-C levels, and goal achievement were determined per Adult Treatment Panel III guidelines. CHD risk assessment incorporated a medical condition review, risk factor summation, and Framingham Risk Score calculation. Percentages were weighted to represent population estimates, and SEs were adjusted for the survey design. The distribution of individuals by CHD risk included 61.1% at lower risk, 10.6% at high risk, and 5.7% at very high risk. From Adult Treatment Panel III criteria, only 5.4% of the population was at “intermediate” risk. Two thirds (66.3%) met their Adult Treatment Panel III–defined LDL-C goal. Of those at high and very high risk, 23% and 26%, respectively, met the goal of LDL-C <100 mg/dL, whereas only 3.1% and 4.6% had an LDL-C <70 mg/dL (or non–high-density lipoprotein C <100 mg/dL).

Conclusions— Most adult US residents are at lower 10-year CHD risk and meet risk-adjusted LDL-C goals. However, large portions of the high-risk population are undertreated. The commonly described population at intermediate risk is small. A novel method of identifying patients who might benefit from additional testing to determine their treatment strategy is provided.

Therapy to reduce risk of coronary heart disease

Recent primary and secondary intervention studies have shown that reduction of low-density lipoprotein cholesterol (LDL-C) with statins significantly reduced coronary heart disease (CHD) morbidity and mortality. However, many patients with dyslipidemia who have or are at risk for CHD do not reach target LDL-C goals. The recently updated National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III guidelines identify a group of patients at very high risk for CHD for more aggressive LDL-C reduction and reaffirm the importance of high-density lipoprotein cholesterol (HDL-C) by raising the categorical threshold to 40 mg/dl. Lipid-lowering therapy needs to be more aggressive in both primary and secondary prevention settings, and therapy should be considered to increase HDL-C as well as lower LDL-C in order to improve patient outcomes. Both combination therapy and the next generation of statins may provide improved efficacy across the dyslipidemia spectrum.

Partners in lowering cholesterol: comparison of a multidisciplinary educational program, monetary incentives, or usual care in the treatment of dyslipidemia identified among employees

OBJECTIVE

We sought to assess whether either a low-cost educational intervention or small monetary incentive is more effective than usual care in lowering low-density lipoprotein (LDL) cholesterol among employees.

METHODS

Employees with an LDL-C >130 mg/dL were eligible. After receiving on-line educational materials, subjects were assigned to three groups: group 1 received dollar 100 if they reduced their LDL-C by 15% within 6 months, group 2 participated in a multi-disciplinary educational program, and group 3 received no further intervention.

RESULTS

In total, 171 employees participated. Baseline mean LDL-C was 156 mg/dL. Approximately 6 months after randomization, mean LDL-C was reduced 17.9 mg/dL (11.3%) in group 1, 17.9 mg/dL (11.5%) in group 2, and 5.5 mg/dL (3.5%) in group 3. Reductions in groups 1 and 2 were statistically superior to group 3 (P = 0.02).

CONCLUSIONS

Both an employer directed low-cost educational program and small monetary incentives similarly lowered LDL-C compared with usual care.

Measurement of carotid artery intima-media thickness in dyslipidemic patients increases the power of traditional risk factors to predict cardiovascular events

A longitudinal observational study investigated whether the measurement, in clinical practice, of carotid maximum intima-media thickness (Max-IMT) could be combined with the Framingham risk score (FRS) to improve the predictability of cardiovascular events in dyslipidemic patients who are at low or intermediate risk. Max-IMT was measured by ultrasound in 1969 patients attending a lipid clinic. The "best threshold values" (BTVs) above which we considered the Max-IMT to be abnormally high were calculated for our dyslipdemic population for each 10-year age interval in men and women. Two hundred and forty-two patients (age 54+/-10 years; 43.8% women) with an FRS <20%, i.e. at low or intermediate risk, were monitored for more than 5 years. Twenty-four of these patients suffered a cardiovascular event within 5.1+/-2.3 years. Both FRS and Max-IMT proved to be independent outcome predictors (p<0.04, both), with a hazard ratio (HR) of 6.7 (95% CI 1.43, 31.04; p=0.015) in patients in whom FRS was 10-20% and Max-IMT was above the BTV (60th percentile of Max-IMT distribution for men or 80th for women). In Kaplan-Meier analysis, the Max-IMT significantly improved the predictive value of the FRS (chi(2)=8.13, p=0.04). Patients with FRS 10-20% (currently considered intermediate-risk) and also elevated Max-IMT values came into the same high-risk category as patients with FRS 20-30%. The combination of FRS with Max-IMT measurement can be used in routine clinical practice to greatly enhance the predictability of cardiovascular events in the large number of patients who fall into the intermediate-risk category, which currently does not call for aggressive preventive measures.

Managing abnormal blood lipids: a collaborative approach

Current data and guidelines recommend treating abnormal blood lipids (ABL) to goal. This is a complex process and requires involvement from various healthcare professionals with a wide range of expertise. The model of a multidisciplinary case management approach for patients with ABL is well documented and described. This collaborative approach encompasses primary and secondary prevention across the lifespan, incorporates nutritional and exercise management as a significant component, defines the importance and indications for pharmacological therapy, and emphasizes the importance of adherence. Use of this collaborative approach for the treatment of ABL ultimately will improve cardiovascular and cerebrovascular morbidity and mortality.

Prevalence of glucose metabolism abnormalities and cardiovascular co-morbidity in the US elderly adult population

PURPOSE

To estimate the prevalence of glucose metabolism abnormalities, including diabetes, and its associated cardiovascular risk factors and co-morbidity in the US elderly population.

METHODS

Cross-sectional analysis of data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) in adults aged 65 years and more. The 1997 American Diabetes Association (ADA) and the 1998 World Health Organization (WHO) criteria were used to classify the subject's glucose metabolism status. The 2-hour oral glucose tolerance test (OGTT) was performed only among those participants aged 40 to 74 years.

RESULTS

The age-adjusted prevalence of diagnosed diabetes was 12.5% (95% CI: 11.4%-13.6%) among US adults aged 65 years or more. According to the ADA definition 40% of men and 28% of women were affected by some degree of glucose metabolism impairment. According to the WHO definition, 55% of men and 50% of women aged 65 to 74 years were affected by glucose metabolism abnormalities. Mexican-Americans were the most affected under both definitions (51% and 77%, respectively). Overall, 72% of elderly diagnosed diabetics had hypertension, 28% had coronary heart disease (CHD), 47% suffered from cardiovascular disease and 80% of them presented known CHD or multiple coronary risk factors, other than age, level of LDL-cholesterol and diabetes. Under both definitions, a trend towards a worsening coronary risk profile with increased glucose metabolism impairment was observed.

CONCLUSION

A notable proportion of elderly people is affected by some degree of glucose metabolism impairment which in turn is associated with cardiovascular co-morbidity.

The break-even point: when medical advances are less important than improving the fidelity with which they are delivered

Society invests billions of dollars in the development of new drugs and technologies but comparatively little in the fidelity of health care, that is, improving systems to ensure the delivery of care to all patients in need. Using mathematical arguments and a nomogram, we demonstrate that technological advances must yield dramatic, often unrealistic increases in efficacy to do more good than could be accomplished by improving fidelity. In 2 examples (the development of anti-platelet agents and statins), we show that enhanced efficacy failed to achieve the health gains that would have occurred by delivering older agents to all eligible patients. Society's huge investment in technological innovations that only modestly improve efficacy, by consuming resources needed for improved delivery of care, may cost more lives than it saves. The misalignment of priorities is driven partly by the commercial interests of industry and by the public's appetite for technological breakthroughs, but health outcomes ultimately suffer. Health, economic, and moral arguments make the case for spending less on technological advances and more on improving systems for delivering care.

Gauging the treatment gap in dyslipidemia: findings from the 1999-2000 National Health and Nutrition Examination Survey

BACKGROUND

Despite published guidelines and availability of many effective lipid-altering therapies, dyslipidemia in the United States remains largely underdiagnosed and undertreated.

METHODS

This study used data from the 1999-2000 National Health and Nutrition Examination Survey to assess the current state of dyslipidemia management in the US adult population compared with guidelines issued by the Third Adult Treatment Panel of the National Cholesterol Education Program. Percentages were weighted to reflect population estimates, computed using SUDAAN (Research Triangle Institution, Cary, NC).

RESULTS

Among 1,425 respondents aged > or = 20 years with complete data, 29.5% were eligible for therapeutic lifestyle changes (TLCs, 16.0%) or lipid-lowering drug therapy (LDT, 13.4%). Among high-risk adults, 79.3% were eligible for either TLC (35.7%) or LDT (43.6%). Only 43.7% of treatment-eligible adults reported ever being diagnosed with dyslipidemia. Of those diagnosed, 77.4% reported being told to undertake TLC, and 34.2% reported being told to take LDT. Of adults eligible for drug therapy, the average percentage reduction in low-density lipoprotein cholesterol (LDL-C) required to reach goal was 28.0% (standard error [SE] 1.1), and 41.9% required a reduction of > 30% in LDL-C to reach goal. Of high-risk adults eligible for drug therapy, the average required reduction was 36.9% (SE 1.4), and 76.3% required a reduction of > 30% in LDL-C.

CONCLUSIONS

Despite advances in dyslipidemia therapy and changes in guidelines over the last decade, LDL-C continues to be inadequately managed among US adults. Of particular concern is the undertreatment of high-risk patients and failure of many treated patients to achieve LDL-C goal.

National trends in statin use by coronary heart disease risk category

BACKGROUND

Only limited research tracks United States trends in the use of statins recorded during outpatient visits, particularly use by patients at moderate to high cardiovascular risk.

METHODS AND FINDINGS

Data collected between 1992 and 2002 in two federally administered surveys provided national estimates of statin use among ambulatory patients, stratified by coronary heart disease risk based on risk factor counting and clinical diagnoses. Statin use grew from 47% of all lipid-lowering medications in 1992 to 87% in 2002, with atorvastatin being the leading medication in 2002. Statin use by patients with hyperlipidemia, as recorded by the number of patient visits, increased significantly from 9% of patient visits in 1992 to 49% in 2000 but then declined to 36% in 2002. Absolute increases in the rate of statin use were greatest for high-risk patients, from 4% of patient visits in 1992 to 19% in 2002. Use among moderate-risk patients increased from 2% of patient visits in 1992 to 14% in 1999 but showed no continued growth subsequently. In 2002, 1 y after the release of the Adult Treatment Panel III recommendations, treatment gaps in statin use were detected for more than 50% of outpatient visits by moderate- and high-risk patients with reported hyperlipidemia. Lower statin use was independently associated with younger patient age, female gender, African American race (versus non-Hispanic white), and non-cardiologist care.

CONCLUSION

Despite notable improvements in the past decade, clinical practice fails to institute recommended statin therapy during many ambulatory visits of patients at moderate-to-high cardiovascular risk. Innovative approaches are needed to promote appropriate, more aggressive statin use for eligible patients.

Characteristics of US adults with the metabolic syndrome and therapeutic implications

BACKGROUND

The third Adult Treatment Panel (ATP III) of the National Cholesterol Education Program defines clinical criteria for diagnosis of the metabolic syndrome, which increases cardiovascular risk and is a target for therapy.

AIM

We analysed the third National Health and Nutrition Examination Survey (NHANES III; 1988-94) to determine how many US adults meet these criteria and are recommended for lipid-modifying drug therapy by ATP III.

METHODS

NHANES III data were used to estimate the number of individuals with the metabolic syndrome and the number recommended for treatment by ATP III, based on 1990 census data.

RESULTS

An estimated 36.3 million (23%) US adults have the metabolic syndrome. Of these, 84% met the criterion for obesity, 76% for blood pressure, 75% for HDL-C, 74% for triglycerides and 41% for glucose. Most (54%) are in the higher risk categories of ATP III, yet only 39% overall are recommended for drug therapy by ATP III cutpoints; of these, most will achieve LDL-C targets with reductions of 35-40%. Of the 15.3 million individuals with the metabolic syndrome and triglycerides > or = 2.26 mmol/l (200 mg/dl), non-HDL-C is above ATP III recommendations in 11.6 million.

CONCLUSIONS

Of the large number of Americans with the metabolic syndrome, ATP III recommends drug therapy for only a minority, because LDL-C typically is not substantially elevated. Instead, high triglycerides and low HDL-C are more common; clinical trial data are needed to determine whether optimal therapy should focus on reductions in LDL-C or on comprehensive improvements to the lipid profile.

Achieving lipoprotein goals in patients at high risk with severe hypercholesterolemia: efficacy and safety of ezetimibe co-administered with atorvastatin

BACKGROUND

Despite the efficacy of statins in lowering low-density lipoprotein cholesterol (LDL-C) levels, many patients who are at high risk for heart disease with hypercholesterolemia require additional LDL-C level reduction. The cholesterol absorption inhibitor, ezetimibe, has been shown to provide significant incremental reductions in LDL-C levels when co-administered with statins. This study was performed to compare the efficacy and safety of ezetimibe (10 mg) plus response-based atorvastatin titration versus response-based atorvastatin titration alone in the attainment of LDL-C goals in subjects who are at high risk for coronary heart disease (CHD) and are not at their LDL-C goal on the starting dose of atorvastatin.

METHODS

This was a 14-week, multicenter, randomized, double-blind, active-controlled study conducted in 113 clinical research centers in 21 countries. Participants were adults with heterozygous familial hypercholesterolemia (HeFH), CHD, or multiple (> or =2) cardiovascular risk factors, and a LDL-C level > or =130 mg/dL after a 6- to 10-week dietary stabilization and atorvastatin (10 mg/day) open-label run-in period. Eligible subjects continued to receive atorvastatin (10 mg) and were randomized to receive blinded treatment with ezetimibe (10 mg/day; n = 305) or an additional 10 mg/day of atorvastatin (n = 316). The atorvastatin dose in both groups was doubled after 4 weeks, 9 weeks, or both when the LDL-C level was not at its goal (< or =100 mg/dL), so that patients receiving combined therapy could reach 40 mg/day and patients receiving atorvastatin alone could reach 80 mg/day. The primary end point was the proportion of subjects achieving their LDL-C level goal at week 14. A secondary end point was the change in LDL-C level and other lipid parameters at 4 weeks after ezetimibe co-administration with 10 mg/day of atorvastatin versus 20 mg/day of atorvastatin monotherapy.

RESULTS

The proportion of subjects reaching their target LDL-C level goal of < or =100 mg/dL was significantly higher in the co-administration group than in the atorvastatin monotherapy group (22% vs 7%; P <.01). At 4 weeks, levels of LDL-C, triglycerides, and non-high-density lipoprotein cholesterol were reduced significantly more by combination therapy than by doubling the dose of atorvastatin (LDL-C -22.8% versus -8.6%; P <.01). The combination regimen had a safety and tolerability profile similar to that of atorvastatin alone.

CONCLUSIONS

The addition of ezetimibe to the starting dose of 10 mg/day of atorvastatin followed by response-based atorvastatin dose titration to a maximum of 40 mg/day provides a more effective means for reducing LDL-C levels in patients at high risk for CHD than continued doubling of atorvastatin as high as 80 mg/day alone.

Achieving greater reductions in cardiovascular risk: lessons from statin therapy on risk measures and risk reduction

Reductions in low-density lipoprotein (LDL) cholesterol with statins have been shown to significantly reduce risk of coronary heart disease (CHD) in the primary- and secondary-prevention settings. Benefit has been observed even in high-risk patients whose baseline LDL cholesterol levels were below the drug initiation levels recommended by current treatment guidelines. Levels of non-high-density lipoprotein cholesterol or total apolipoprotein B more accurately reflect circulating levels of atherogenic particles than does LDL cholesterol concentration, and may provide a surrogate marker that correlates better to CHD event reduction after statin therapy than LDL cholesterol level. More effective lipid-lowering therapy than that currently practiced may be needed in many patients to achieve optimal CHD risk reduction.

Development of a parametric simulation model for forecasting goal-oriented treatment outcomes

BACKGROUND

Treatment-to-goal (TTG) analyses are frequently used to predict guideline-directed population control rates for drug therapies based on mean efficacy data. Nevertheless, estimates are commonly inaccurate because variability in efficacy is not considered. A new methodology was developed to improve TTG forecasting.

METHODS

Patient-level blood pressure (BP) lowering data sets, designed to simulate clinical trial results, were generated for testing from three underlying distributions: normal, lognormal, and beta. To emulate real-world conditions where patient-level data are unavailable, two approaches were considered: parametric--simulated BP lowering data were generated using the mean and standard deviation of the test data sets; and point-estimate--BP lowering was uniformly assigned as the mean lowering. BP control (systolic BP < 140 and diastolic BP < 90 mmHg) was forecasted by subtracting values generated by these two methods from baseline BP values in untreated hypertensive patients (n = 2483) from the Third National Health and Nutrition Examination Survey. Estimated control rates were compared to analyses where the patient-level data sets were bootstrapped.

RESULTS

We assumed mean (+/- SD) BP lowering of 20 (12) mmHg systolic and 14 (7) mmHg diastolic. Parametric method predicted a BP control rate of 66.9% [95% confidence interval (CI) 65.7-67.9], similar to the bootstrapping approach (67.3%, 95% CI 65.9-68.8). The control rate projected based on the point-estimate method was 75.5%. The point-estimate method frequently led to substantially different results under a wide range of model assumptions.

CONCLUSIONS

A new parametric-based forecasting method, which addresses underlying variability, improves on estimates based on mean efficacy only. In the absence of patient-level data, this method is generalizable to different therapeutic areas.

Screening Coronary Arteriography in the Primary Prevention of Coronary Artery Disease

Recent studies indicate an expansion of the population eligible for primary prevention of coronary artery disease with lipid-lowering therapy. This change has led to the unnecessary treatment of many individuals and an overall decreased effectiveness of medication with potentially significant side effects. If instead, the asymptomatic population is screened for the presence of early coronary artery disease (CAD), lipid lowering can be targeted to those who can truly benefit. The prevalence of asymptomatic CAD in men older than 50 years of age approaches 20% and arteriography is currently the best available test to identify these men. The approximate complication rate of arteriography in such a population (1 or 2 per 10,000) approaches that of other screening tests. Although insufficient data exists for formal cost analysis, approximations indicate significant savings for arteriographically targeted treatment of at-risk asymptomatic individuals. The authors show that coronary arteriography is a potentially safe and cost-effective method of screening an asymptomatic adult population for presence of early CAD, allowing for the targeting of lipid lowering to those who can benefit most from this therapy.

Managing the spectrum of dyslipidemia in primary care

Dyslipidemia, especially elevated low-density lipoprotein cholesterol (LDL-C), increases the risk of coronary heart disease and subsequent morbidity or mortality. For more than a decade, the National Cholesterol Education Program (NCEP) has endeavored to raise awareness of the dangers of dyslipidemia and to encourage the implementation of recommended treatment strategies. However, despite this initiative, previously published NCEP targets were not met. The recently released NCEP-Adult Treatment Panel III guidelines recommend more aggressive LDL-C reduction, elevation of categorical low high-density lipoprotein binding protein, and increased monitoring of moderate triglyceride elevations. Although the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are the most powerful medications available to reduce LDL-C, studies have shown that more than half of patients treated with these drugs do not achieve therapeutic targets and the resultant decrease in coronary heart disease events. There are a number of possible reasons for this, including potency of the statins and a lack of compliance on the part of patients and providers. Another concern with the available statins is the issue of drug-drug interactions. Some of these concerns may be addressed by newer agents in this drug class that are in development. They appear to have the potential to induce even greater reductions in LDL-C and to positively affect other lipoproteins. They also have the potential for less risk of drug-drug interactions. Nurse practitioners can play a pivotal role in improving the management of dyslipidemia by ensuring the proper implementation of current guidelines, helping patients adhere to treatment protocols, and remaining abreast of developments that may pave the way toward even more effective intervention in the future.

Effective strategies for long-term statin use

Long-term statin use achieves a significant reduction in mortality (24% to 42%) for patients with coronary artery disease (CAD) that is equal to or greater than that seen with other secondary prevention medications, including aspirin, beta-blockers, and angiotensin-converting enzyme (ACE) inhibitors. In patients with diabetes, the reduction in mortality exceeds that seen with tight glycemic control or any other treatment for diabetes. Several studies have found that almost all patients with atherosclerosis are considered candidates for statin treatment. The scientific evidence needed to revise the national guidelines has been provided by showing that initiation of statins before hospital discharge results in (1). a marked increase in long-term treatment rates, (2). improved long-term patient compliance, (3). more patients reaching levels of low-density lipoprotein (LDL) cholesterol <100 mg/dL, and (4). improved clinical outcome. Nonetheless, many studies in a variety of clinical settings have demonstrated that, regardless of the health care delivery system, an unacceptable number of patients with atherosclerosis are left untreated or undertreated with statin therapy. Applying hospital-based systems has been demonstrated to address the problems of underuse. The national guidelines now recommend that, in addition to diet and exercise counseling, lipid-lowering medications be initiated before hospital discharge for patients diagnosed with cardiovascular disease. Optimal use of statins and other cardioprotective medications in high-risk patients could save >83000 lives per year in the United States.

Statin therapy after acute myocardial infarction: are we adequately treating high-risk patients?

After acute myocardial infarction, patients remain at high risk for recurrent cardiovascular events and mortality. Despite the compelling scientific and clinical trial evidence that lipid-lowering medications reduce mortality in patients after acute myocardial infarction, this life-saving therapy continues to be underutilized. A number of studies in a variety of clinical settings have documented that a significant proportion of patients after myocardial infarction are not receiving treatment with lipid-lowering medications when guided by conventional care. It has recently been demonstrated that implementation of a hospital-based system for initiation of statins prior to hospital discharge results in a marked increase in treatment rates, improved long-term patient compliance, more patients reaching low-density lipoprotein levels of less than 100 mg/dL, and improved clinical outcomes. Adopting in-hospital initiation of lipid-lowering medications as the standard of care for patients hospitalized with acute myocardial infarction could dramatically improve treatment rates and thus substantially reduce the risk of future coronary events and prolong life in the large number of patients hospitalized each year.