Evaluation of effects of unmodified niacin on fasting and postprandial plasma lipids in normolipidemic men with hypoalphalipoproteinemia

Mechanisms of Atherosclerosis Induced by Postprandial Lipemia

Postprandial lipemia plays an important role in the formation, occurrence, and development of atherosclerosis, and it is closely related to coronary heart disease and other diseases involving endothelial dysfunction, oxidative stress, inflammation, and other mechanisms. Therefore, it has become a focus area for further research. The studies on postprandial lipemia mainly include TG, TRL, VLDL, CM, and remnant cholesterol. Diurnal triglyceride patterns and postprandial hyperlipidemia are very relevant and are now insufficiently covered. The possible mechanisms between postprandial lipemia and cardiovascular disease have been reviewed in this article by referring to relevant literature in recent years. The research progress on the effects of postprandial lipemia on endothelial function, oxidative stress, and inflammation is highlighted. The intervention of postprandial lipemia is discussed. Non-medicinal intervention such as diet and exercise improves postprandial lipemia. As medicinal intervention, statin, fibrate, ezetimibe, omega-3 fatty acids, and niacin have been found to improve postprandial lipid levels. Novel medications such as pemafibrate, PCSK9, and apoCIII inhibitors have been the focus of research in recent years. Gut microbiota is closely related to lipid metabolism, and some studies have indicated that intestinal microorganisms may affect lipid metabolism as environmental factors. Whether intervention of gut microbiota can reduce postprandial lipemia, and therefore against AS, may be worthy of further study.

Abrogation of postprandial triglyceridemia with dual PPAR α/γ agonist in type 2 diabetes mellitus: a randomized, placebo-controlled study

AIMS

Lowering postprandial lipemia may mitigate cardiovascular risk in patients with diabetic dyslipidemia. This study was aimed to investigate whether saroglitazar suppresses postprandial lipemia in patients with diabetes and dyslipidemia.

METHODS

This was a 12-week, prospective, multicenter, randomized, double-blinded, placebo-controlled study of saroglitazar in patients with diabetes and dyslipidemia. Thirty patients were randomized (1:1) to receive saroglitazar 4 mg or placebo orally once daily with metformin for 12 weeks. The primary endpoint was change in plasma triglyceride (TG) area under the curve (AUC) on a standardized 8-h fat tolerance test.

RESULTS

Thirty participants were randomized for interventions and eventually data of 19 participants qualified for per protocol analyses. Mean (SD) age in saroglitazar was 53.1 (8.8) years and 54.9 (7.7) years in placebo group. After 12 weeks, saroglitazar significantly lowered postprandial TG-AUC by - 458.3 (144.0) (- 25.7%, 95% CI - 765.1 to - 151.4) versus an increase of + 10.9 (157.9) (+ 0.5%, 95% CI - 325.6 to 347.3) mg/dL h in placebo group (P < 0.05). Saroglitazar lowered postprandial TG incremental AUC versus placebo: - 329.4 (89.9) (- 59%) versus + 80.4 (99.4) (+ 10%) mg/dL h (P < 0.05). HbA1c (%) decreased by - 0.36 (0.42) in the saroglitazar group as compared to an increase of + 1.26 (0.46) (P < 0.05) with placebo.

CONCLUSIONS

The saroglitazar treatment significantly improved postprandial TGs in people with diabetic dyslipidemia.

TRIAL REGISTRATION

Clinical Trial Registry of India; trial Registration No.: CTRI/2015/06/005845 and Date of registration: June 02, 2015.

Effect of Nutrient and Micronutrient Intake on Chylomicron Production and Postprandial Lipemia

Postprandial lipemia, which is one of the main characteristics of the atherogenic dyslipidemia with fasting plasma hypertriglyceridemia, low high-density lipoprotein cholesterol and an increase of small and dense low-density lipoproteins is now considered a causal risk factor for atherosclerotic cardiovascular disease and all-cause mortality. Postprandial lipemia, which is mainly related to the increase in chylomicron production, is frequently elevated in individuals at high cardiovascular risk such as obese or overweight patients, type 2 diabetic patients and subjects with a metabolic syndrome who share an insulin resistant state. It is now well known that chylomicron production and thus postprandial lipemia is highly regulated by many factors such as endogenous factors: circulating factors such as hormones or free fatty acids, genetic variants, circadian rhythms, or exogenous factors: food components, dietary supplements and prescription drugs. In this review, we focused on the effect of nutrients, micronutrients and phytochemicals but also on food structure on chylomicron production and postprandial lipemia.

Postprandial lipemia as a cardiometabolic risk factor

High levels of fasting circulating triglycerides (TG) represent an independent risk factor for cardiovascular disease. In western countries, however, people spend most time in postprandial conditions, with continuous fluctuation of lipemia due to increased levels of TG-rich lipoproteins (TRLs), including chylomicrons (CM), very low density lipoproteins (VLDL), and their remnants. Several factors contribute to postprandial lipid metabolism, including dietary, physiological, pathological and genetic factors. The presence of coronary heart disease, type 2 diabetes, insulin resistance and obesity is associated with higher postprandial TG levels compared with healthy conditions; this association is present also in subjects with normal fasting TG levels. Increasing evidence indicates that impaired metabolism of postprandial lipoproteins contributes to the pathogenesis of coronary artery disease, suggesting that lifestyle modifications as well as pharmacological approaches aimed at reducing postprandial TG levels might help to decrease the cardiovascular risk.

Recent advances in pharmacotherapy for hypertriglyceridemia

Elevated plasma triglyceride (TG) concentrations are associated with an increased risk of atherosclerotic cardiovascular disease (CVD), hepatic steatosis and pancreatitis. Existing pharmacotherapies, such as fibrates, n-3 polyunsaturated fatty acids (PUFAs) and niacin, are partially efficacious in correcting elevated plasma TG. However, several new TG-lowering agents are in development that can regulate the transport of triglyceride-rich lipoproteins (TRLs) by modulating key enzymes, receptors or ligands involved in their metabolism. Balanced dual peroxisome proliferator-activated receptor (PPAR) α/γ agonists, inhibitors of microsomal triglyceride transfer protein (MTTP) and acyl-CoA:diacylglycerol acyltransferase-1 (DGAT-1), incretin mimetics, and apolipoprotein (apo) B-targeted antisense oligonucleotides (ASOs) can all decrease the production and secretion of TRLs; inhibitors of cholesteryl ester transfer protein (CETP) and angiopoietin-like proteins (ANGPTLs) 3 and 4, monoclonal antibodies (Mabs) against proprotein convertase subtilisin/kexin type 9 (PCSK9), apoC-III-targeted ASOs, selective peroxisome proliferator-activated receptor modulators (SPPARMs), and lipoprotein lipase (LPL) gene replacement therapy (alipogene tiparvovec) enhance the catabolism and clearance of TRLs; dual PPAR-α/δ agonists and n-3 polyunsaturated fatty acids can lower plasma TG by regulating both TRL secretion and catabolism. Varying degrees of TG reduction have been reported with the use of these therapies, and for some agents such as CETP inhibitors and PCSK9 Mabs findings have not been consistent. Whether they reduce CVD events has not been established. Trials investigating the effect of CETP inhibitors (anacetrapib and evacetrapib) and PCSK9 Mabs (AMG-145 and REGN727/SAR236553) on CVD outcomes are currently in progress, although these agents also regulate LDL metabolism and, in the case of CETP inhibitors, HDL metabolism. Further to CVD risk reduction, these new treatments might also have a potential role in the management of diabetes and non-alcoholic fatty liver disease owing to their insulin-sensitizing action (PPAR-α/γ agonists) and potential capacity to decrease hepatic TG accumulation (PPAR-α/δ agonists and DGAT-1 inhibitors), but this needs to be tested in future trials. We summarize the clinical trial findings regarding the efficacy and safety of these novel therapies for hypertriglyceridemia.

Postprandial hypertriglyceridemia and cardiovascular disease: current and future therapies

Exaggerated postprandial hypertriglyceridemia is a risk factor for cardiovascular disease. This metabolic abnormality is principally due to overproduction and/or decreased catabolism of triglyceride-rich lipoproteins (TRLs) and is a consequence of pathogenic genetic variations and other coexistent medical conditions, particularly obesity and insulin resistance. Accumulation of TRL in the postprandial state promotes the formation of small, dense low-density lipoproteins, as well as oxidative stress, inflammation, and endothelial dysfunction, all of which compound the risk of cardiovascular disease. The cardiovascular benefits of lifestyle modification (weight loss and exercise) and conventional lipid-lowering therapies (statins, fibrates, niacin, ezetimibe, and n-3 fatty acid supplementation) could involve their favorable effects on TRL metabolism. New agents, such as dual peroxisome-proliferator-activated receptor α/δ agonists, diacylglycerol, inhibitors of diacylglycerol acyltransferase 1 and microsomal triglyceride transfer protein, antisense oligonucleotides for apolipoprotein B-100 and apolipoprotein C-III, and incretin-based therapies, may enhance the treatment of postprandial lipemia, but their efficacy needs to be tested in clinical end point trials. Further work is required to develop a simple clinical protocol for investigating postprandial lipemia, as well as internationally agreed management guidelines for this type of dyslipidemia.

Extended-release niacin acutely suppresses postprandial triglyceridemia

OBJECTIVE

Postprandial triglyceridemia predicts cardiovascular events. Niacin might lower postprandial triglycerides by restricting free fatty acids. Immediate-release niacin reduced postprandial triglycerides, but extended-release niacin failed to do so when dosed the night before a fat challenge. The study aims were to determine whether extended-release niacin dosed before a fat challenge suppresses postprandial triglycerides and whether postprandial triglycerides are related to free fatty acid restriction.

METHODS

A double-blinded, placebo-controlled, random-order crossover experiment was performed, in which healthy volunteers took 2 g extended-release niacin or placebo 1 hour before heavy cream. We sampled blood over 12 hours and report triglycerides and free fatty acid as means ± standard deviation for incremental area under the curve (AUC) and nadir.

RESULTS

By combining 43 fat challenges from 22 subjects, postprandial triglycerides incremental AUC was +312 ± 200 mg/dL*h on placebo versus +199 ± 200 mg/dL*h on extended-release niacin (33% decrease, P=.02). The incremental nadir for free fatty acid was -0.07 ± 0.15 mmol/L on placebo versus -0.27 ± 0.13 mmol/L on extended-release niacin (P<.0001), and free fatty acid incremental AUC decreased from +2.9 ± 1.5 mmol/L*h to +1.5 ± 1.5 mmol/L*h on extended-release niacin (20% decrease, P=.0015). The incremental AUC for triglycerides was strongly related to the post-dose decrease in free fatty acid (r = +0.58, P=.0007).

CONCLUSIONS

Given right before a fat meal, even a single dose of extended-release niacin suppresses postprandial triglyceridemia. This establishes that postprandial triglycerides suppression is an acute pharmacodynamic effect of extended-release niacin, probably the result of marked free fatty acid restriction. Further study is warranted to determine whether mealtime dosing would augment the clinical efficacy of extended-release niacin therapy.

Potential drug interactions associated with treatments for type 2 diabetes and its comorbidities: a clinical pharmacology review

Type 2 diabetes is a disease of glucose metabolism that commonly involves multiple comorbidities, including lipid dyscrasias and hypertension. Each concurrent disorder contributes some risk of complications and requires therapeutic intervention. The simultaneous management of so many coexisting illnesses can be complex and commonly results in patients being prescribed multiple medications--referred to as polypharmacy--which may further complicate treatment. To ensure the best patient outcomes, the treating physician must be aware of all the therapeutic agents that a patient is taking to assess possible drug interactions that such a plethora of medications may confer. This article addresses the underlying comorbidites, the drugs commonly used to treat them and the interactions that may arise from concomitant administration.

Important considerations for treatment with dietary supplement versus prescription niacin products

Niacin is a water-soluble B vitamin (B3) known to have favorable effects on multiple lipid parameters, including raising high-density lipoprotein cholesterol (HDL-C) levels and lowering triglycerides (TGs), lipoprotein(a), and low-density lipoprotein cholesterol (LDL-C). Although LDL-C remains the primary target of lipid-altering therapy, current guidelines emphasize HDL-C and other modifiable lipid factors as key secondary targets. Thus, niacin is considered an important therapeutic option to help reduce the risk of cardiovascular disease in patients with mixed dyslipidemia who, in addition to high LDL-C, have elevated TGs and low HDL-C. Although available prescription niacin products, including immediate-release niacin (IR; Niacor) and an extended-release niacin formulation (Niaspan), have demonstrated safety and efficacy in randomized clinical trials, confusion remains among health care providers and their patients regarding the various commercially available nonprescription dietary supplement niacin products. These dietary supplements, which include IR, sustained-release (SR), and "no-flush" or "flush-free" niacin products, are not subject to the same stringent US Food and Drug Administration regulations as prescription drugs. In fact, both the American Heart Association and the American Pharmacists Association recommend against the use of dietary supplement niacin as a substitute for prescription niacin. Although some dietary supplement IR and SR niacin products have demonstrated a lipid response in clinical trials, products labeled as "no-flush" or "flush-free" that are intended to avoid the common niacin-associated adverse effect of flushing generally contain minimal or no free, pharmacologically active niacin and therefore lack beneficial lipid-modifying effects. To clarify important differences between available prescription and dietary supplement niacin products, this article contrasts current regulatory standards for dietary supplements and prescription drugs and provides an overview of available clinical data from key trials of niacin.

A "hot" topic in dyslipidemia management--"how to beat a flush": optimizing niacin tolerability to promote long-term treatment adherence and coronary disease prevention

Niacin is the most effective lipid-modifying agent for raising high-density lipoprotein cholesterol levels, but it also causes cutaneous vasodilation with flushing. To determine the frequency of flushing in clinical trials, as well as to delineate counseling and treatment approaches to prevent or manage flushing, a MEDLINE search was conducted of English-language literature from January 1, 1985, through April 7, 2009. This search used the title keywords niacin or nicotinic acid crossed with the Medical Subject Headings adverse effects and human. Niacin flushing is a receptor-mediated, mainly prostaglandin D(2)-driven phenomenon, the frequency, onset, and duration of which are largely determined by the distinct pharmacological and metabolic profiles of different niacin formulations. Subjective assessments include ratings of redness, warmth, itching, and tingling. In clinical trials, most (>60%) niacin users experienced mild or moderate flushing, which tended to decrease in frequency and severity with continued niacin treatment, even with advancing doses. Approximately 5% to 20% of patients discontinued treatment because of flushing. Flushing may be minimized by taking niacin with meals (or at bedtime with a low-fat snack), avoiding exacerbating factors (alcohol or hot beverages), and taking 325 mg of aspirin 30 minutes before niacin dosing. The current review advocates an initially slow niacin dose escalation from 0.5 to 1.0 g/d during 8 weeks and then from 1.0 to 2.0 g in a single titration step (if tolerated). Through effective counseling, treatment prophylaxis with aspirin, and careful dose escalation, adherence to niacin treatment can be improved significantly. Wider implementation of these measures should enable higher proportions of patients to reach sufficient niacin doses over time to prevent cardiovascular events.

Independent and combined effects of aerobic exercise and pharmacological strategies on serum triglyceride concentrations: a qualitative review

Elevated fasting and postprandial serum triglyceride concentrations are associated with cardiovascular disease morbidity and mortality. Aerobic exercise reduces serum triglyceride concentrations in the presence or absence of weight loss. Although pharmacological interventions are often used in combination with aerobic exercise to achieve target triglyceride concentrations, information on the combined effects of aerobic exercise and lipid-modifying agents on serum triglycerides is limited. This review examines the independent and combined effects of both interventions on serum fasting and postprandial triglyceride concentrations from the available literature. Reductions in serum triglycerides after aerobic exercise are associated with an increase in skeletal muscle lipoprotein lipase activity and a decrease in hepatic triglyceride and very-low-density lipoprotein (VLDL) synthesis and secretion. Lipid-modifying agents such as niacin, omega-3 fatty acids, and statins also decrease fasting and postprandial triglycerides by increasing lipoprotein lipase (LPL) activity and/or decreasing VLDL synthesis. When combined, lipid-modifying agents may reduce fasting and postprandial triglyceride secretion to an extent in which aerobic exercise cannot provide any additional benefit. These observations indicate that aerobic exercise and pharmacological strategies reduce serum triglycerides by similar mechanisms, which may attenuate the triglyceride-lowering capacity of the concordant treatment.

Novel aspects of postprandial lipemia in relation to atherosclerosis

Postprandial hyperlipidemia is considered to be a substantial risk factor for atherosclerosis. Interestingly, this concept has never been supported by randomized clinical trials. The difficulty lies in the fact that most interventions aimed to reduce postprandial lipemia, will also affect LDL-C levels. The atherogenic mechanisms of postprandial lipids and lipoproteins can be divided into direct lipoprotein-mediated and indirect effects; the latter, in part, by inducing an inflammatory state. Elevations in postprandial triglycerides (TG) have been related to the increased expression of postprandial leukocyte activation markers, up-regulation of pro-inflammatory genes in endothelial cells and involvement of the complement system. This set of events is part of the postprandial inflammatory response, which is one of the recently identified potential pro-atherogenic mechanisms of postprandial lipemia. Especially, complement component 3 levels show a close correlation with postprandial lipemia and are also important determinants of the metabolic syndrome. In clinical practice, fasting TG are frequently used as reflections of postprandial lipemia due to the close correlation between the two. The use of serial capillary measurements in an out-of-hospital situation is an alternative for oral fat loading tests. Daylong TG profiles reflect postprandial lipemia and are increased in conditions like the metabolic syndrome, type 2 diabetes and atherosclerosis. Studies are needed to elucidate the role of postprandial inflammation in atherogenesis and to find new methods in order to reduce selectively the postprandial inflammatory response. Future studies are needed to find new methods in order to reduce selectively the postprandial inflammatory response.

Postprandial triglyceride responses to aerobic exercise and extended-release niacin

BACKGROUND

Aerobic exercise and niacin are frequently used strategies for reducing serum triglycerides, and, yet, there is no information regarding the combined effects of these strategies on postprandial triglycerides.

OBJECTIVE

We compared the effects of aerobic exercise and 6 wk of extended-release niacin on postprandial triglycerides in men with the metabolic syndrome.

DESIGN

Fifteen participants underwent each of 4 conditions: control--high-fat meal only (100 g fat); exercise--aerobic exercise performed 1 h before a high-fat meal; niacin--high-fat meal consumed after 6 wk of niacin; and niacin + exercise--high-fat meal consumed after 6 wk of niacin and 1 h after aerobic exercise. Temporal responses for triglyceride and insulin concentrations were measured and total (AUC(T)) and incremental (AUC(I)) areas under the curve were calculated. Differences were determined by using a 2-factor repeated-measures analysis of variance (P < 0.05 for all).

RESULTS

Exercise lowered the triglyceride AUC(I) by 32% compared with control (724 +/- 118 and 1058 +/- 137, respectively). Niacin had no influence on the triglyceride AUC(I) and attenuated the triglyceride-lowering effect of exercise when combined. Niacin + exercise had no effect on the triglyceride AUC(I) but decreased the insulin AUC(I) after niacin administration.

CONCLUSIONS

Aerobic exercise lowers the postprandial triglyceride response to a high-fat meal. Niacin lowers fasting but not postprandial triglycerides and appears to influence the triglyceride-lowering effect of aerobic exercise when combined. However, exercise decreases postprandial insulin concentrations after niacin administration, which illustrates the potential metabolic benefits of exercise in persons taking niacin.

Strategic approach to fit-for-purpose biomarkers in drug development

The strategic, fit-for-purpose use of the combination of robust target engagement and well-qualified disease-related biomarkers enhances understanding of the mechanism of action, ties together preclinical and clinical data, enables the assessment of target engagement, facilitates early proof of concept and dose focusing, and increases the efficiency of early clinical development with improved quality of decision making. Significant progress in biomarker discovery, validation, and qualification has increased drug-development decision making and regulatory applications. Target engagement biomarkers are present early in a pathophysiologic cascade and inform on physical or biological interactions with the molecular target of the drug. Disease-related biomarkers are present late in the pathophysiologic cascade and are linked to clinical benefit; thus, they assess a drug's effect on a particular disease. Together, these concepts lay the groundwork for high-quality drug-development decision making and a framework for the acceptance and qualification of biomarkers for regulatory use.

Suppression of Niacin-induced Vasodilation with an Antagonist to Prostaglandin D2 Receptor Subtype 1

Niacin (nicotinic acid) reduces cardiovascular events in patients with dyslipidemia. However, symptoms associated with niacin-induced vasodilation (e.g., flushing) have limited its use. Laropiprant is a selective antagonist of the prostaglandin D(2) receptor subtype 1 (DP1), which may mediate niacin-induced vasodilation. The aim of this proof-of-concept study was to evaluate the effects of laropiprant (vs placebo) on niacin-induced cutaneous vasodilation. Coadministration of laropiprant 30, 100, and 300 mg with extended-release (ER) niacin significantly lowered flushing symptom scores (by approximately 50% or more) and also significantly reduced malar skin blood flow measured by laser Doppler perfusion imaging. Laropiprant was effective after multiple doses in reducing symptoms of flushing and attenuating the increased malar skin blood flow induced by ER niacin. In conclusion, the DP1 receptor antagonist laropiprant was effective in suppressing both subjective and objective manifestations of niacin-induced vasodilation.

Inhibition of cholesteryl ester transfer protein by torcetrapib modestly increases macrophage cholesterol efflux to HDL

OBJECTIVE

This study examines the effects of pharmacological inhibition of cholesteryl ester transfer protein (CETP) on the ability of high-density lipoprotein particles (HDL) to promote net cholesterol efflux from human THP-1 macrophage foam cells.

METHODS AND RESULTS

Two groups of 8 healthy, moderately hyperlipidemic subjects received the CETP inhibitor torcetrapib at 60 or 120 mg daily for 8 weeks. Torcetrapib increased HDL cholesterol levels in both groups by 50% and 60%, respectively. Compared with baseline, torcetrapib 60 mg daily increased HDL-mediated net cholesterol efflux from foam cells primarily by increasing HDL concentrations, whereas 120 mg daily torcetrapib increased cholesterol efflux both by increasing HDL concentration and by causing increased efflux at matched HDL concentrations. There was an increased content of lecithin:cholesterol acyltransferase (LCAT) and apolipoprotein E (apoE) in HDL-2 only at the 120 mg dose. ABCG1 activity was responsible for 40% to 50% of net cholesterol efflux to both control and T-HDL.

CONCLUSIONS

These data indicate that inhibition of CETP by torcetrapib causes a modest increase in the ability of HDL to promote net cholesterol efflux at the 60 mg dose, and a more dramatic increase at the 120 mg dose in association with enhanced particle functionality.

Efficacy and safety of high-density lipoprotein cholesterol-increasing compounds: a meta-analysis of randomized controlled trials

OBJECTIVES

The aim of this research was to estimate the efficacy and safety of current high-density lipoprotein cholesterol (HDL-C)-increasing drugs.

BACKGROUND

Epidemiologic evidence has shown that HDL-C is inversely related to coronary heart disease (CHD) risk. However, the evidence for reducing CHD risk by raising HDL-C is thin, predominantly due to the paucity of effective and safe HDL-increasing drugs.

METHODS

Randomized controlled trials with fibrates and niacin, published between 1966 through February 2004 (MEDLINE), were retrieved. Information on treatment, baseline characteristics, serum lipids, end points, and side-effects were independently abstracted by two authors using a standardized protocol.

RESULTS

Data from 53 trials (16,802 subjects) using fibrates and 30 trials (4,749 subjects) using niacin were included. Random-effects model showed 11% versus 10% reduction in total cholesterol, 36% versus 20% reduction in triglycerides, 8% versus 14% reduction in low-density lipoprotein cholesterol, and 10% versus 16% increase in HDL-C for fibrates and niacin, respectively. Apart from flushes in the niacin group, both fibrates and niacin were shown to be well-tolerated and safe. Fibrates reduced the risk for major coronary events by 25% (95% confidence interval 10% to 38%), whereas current available data for niacin indicate a 27% reduction.

CONCLUSIONS

Fibrates reduce major coronary events and increase HDL-C levels without significant toxicity. Niacin has a more potent effect on HDL-C levels, whereas data on cardiovascular event rate reduction are limited. Future studies need to evaluate whether additional HDL increase by fibrates or particularly newer niacin formulations on top of statin therapy translates into further event reduction in high-risk subjects, without significant toxicity.

Role of CETP inhibitors in the treatment of dyslipidemia

PURPOSE OF REVIEW

This review summarizes novel human data on cholesteryl ester-transfer protein (CETP) and atherosclerosis and the possible use of CETP inhibitors in the treatment of dyslipidemia. In addition, it will underline that therapeutic targeting of the high-density lipoprotein (HDL) metabolism entails more than simply observing changes in cholesterol levels of this lipoprotein.

RECENT FINDINGS

Two pharmacological small-molecule inhibitors of CETP, JTT-705 and torcetrapib, have recently been shown to effectively raise HDL cholesterol in humans without serious side effects when either used as a monotherapy or combined with statins that lower low-density lipoprotein cholesterol. Importantly, prospective data from the Epic-Norfolk study furthermore indicate that elevated CETP concentration in conjunction with elevated triglyceride levels are associated with increased odds for cardiovascular events. Data from the Diabetic Atherosclerosis Intervention Study furthermore show that elevated CETP concentration is associated with increased progression of coronary atherosclerosis in patients with type 2 diabetes who use fenofibrate.

SUMMARY

Long-term studies will have to show whether CETP inhibition decreases the risk of atherosclerotic disease in dyslipidemic patients. Increased CETP activity might be detrimental under hypertriglyceridemic conditions which is of importance when considering that a large proportion of patients at increased risk from coronary artery disease exhibit elevated triglyceride levels. Studies into the effects of CETP inhibition in hypertriglyceridemic patients therefore seem warranted. Awaiting the first data on the effect of CETP inhibition on surrogate endpoints for atherosclerosis, this review furthermore outlines that the complexity of HDL metabolism will necessitate a wide variety of studies on many aspects of this intriguing lipoprotein.

Phosphatidylinositol increases HDL-C levels in humans

Studies have shown that phosphatidylinositol (PI) can stimulate reverse cholesterol transport by enhancing the flux of cholesterol into HDL and by promoting the transport of high density lipoprotein-cholesterol (HDL-C) to the liver and bile. The goal of this study was to determine the safety and therapeutic value of PI after oral administration to normolipidemic human subjects. We performed a randomized 2 week study in 16 normolipidemic subjects. Subjects received either 2.8 or 5.6 g of PI, with or without food. PI was well tolerated by all subjects. PI significantly affected the levels of HDL-C and triglyceride in the plasma of subjects receiving PI with food. The lower dose showed a 13% increase in HDL-C, whereas the high dose showed an increase of 18% over the 2 week period. Both low- and high-dose groups showed significant increases in plasma apolipoprotein A-I. The high dose of PI also decreased plasma triglycerides by 36% in the fed subjects. These data suggest that after only 2 weeks, PI may have a comparable therapeutic value to niacin, with negligible side effects.

Ex vivo measures of LDL oxidative susceptibility predict carotid artery disease

AIM

The purpose of the study was to assess whether ex vivo measures of low-density lipoprotein (LDL) oxidation improved prediction of carotid artery disease (CAAD) case-control status compared to standard lipid and smoking measures.

METHODS

One hundred and forty cases with a high degree of carotid artery stenosis aged 40-83 years and an equal number of controls without stenosis or other vascular disease were matched by censored age within 2 years. Matched logistic regression evaluated the significance of copper-induced oxidative measures with and without covariates. The relationship of LDL oxidation measures with statin use and current smoking was also evaluated.

RESULTS

Logistic regression demonstrated a significant effect of the three correlated measures of oxidative susceptibility (lag time, oxidation rate and maximal rate of oxidation) separately on disease prediction (all p<0.05). These oxidative measures remained significant predictors of case-control status when other cardiovascular disease predictors (age; LDL-C, HDL-C and ApoAI levels; current smoking, ever smoking and pack-years smoked) were jointly considered. This relationship was not attributable to the effects of statin use on LDL oxidation.

CONCLUSIONS

Ex vivo measures of oxidation improved the prediction of carotid artery disease status, suggesting that this is an important determinant of atherosclerotic risk in this older population.

Management of the metabolic syndrome-nicotinic acid

Nicotinic acid effectively treats each of the common lipid abnormalities found in the metabolic syndrome, and much progress has recently been made in understanding its mechanisms of action. Early concern that nicotinic acid can precipitate or worsen diabetes has been eased with recent trials, which demonstrated its safety and effectiveness in insulin-resistant states. Furthermore, nicotinic acid prevents cardiovascular disease and death in persons with a high prevalence of risk factors for the metabolic syndrome. When used by an experienced physician and taken by a motivated patient, nicotinic acid can be safe and effective in treating the dyslipidemia of the metabolic syndrome.

Niacin in HIV-infected individuals with hyperlipidemia receiving potent antiretroviral therapy

BACKGROUND

Extended release (ER)-niacin therapy, which has been associated with reduced glucose tolerance in human immunodeficiency virus (HIV)-seronegative individuals, has not been evaluated in the HIV-infected population.

METHODS

This open, prospective trial evaluated the safety and efficacy of ER-niacin therapy for antiretroviral therapy-associated dyslipidemia. Fourteen individuals received ER-niacin at maximum doses of 2000 mg per day for 14 weeks.

RESULTS

Significant reductions in serum levels of triglycerides (P=.02), total cholesterol (P=.005), and non-HDL cholesterol (P=.04) were seen after ER-niacin therapy. Seven of 11 subjects were glucose intolerant after ER-niacin therapy; for 3 of these subjects, this was a new finding. Beta-cell sensitivity to basal glucose levels increased significantly without concomitant increase in overall glucose disposition indices. The values for the homeostasis model of insulin resistance index increased significantly (P=.005).

CONCLUSION

ER-niacin's role in the treatment of antiretroviral therapy-associated dyslipidemia requires further evaluation, but the results of this pilot study indicate that it is safe and tolerated and provides a valuable treatment option.

Effects of nonstatin lipid drug therapy on high-density lipoprotein metabolism

Low high-density lipoprotein (HDL) cholesterol is an important predictor of risk for coronary artery disease. Although current treatment guidelines for dyslipidemia do not include specific targets for HDL cholesterol, the categorical definition of low HDL cholesterol has been changed from <35 mg/dL to <40 mg/dL. 3-hydroxy-3-methylglutaryl reductase inhibitors (statins) increase HDL cholesterol to a moderate degree. Fibrates also increase HDL cholesterol to a moderate degree and have additive effects with statins. Niacin is the most potent currently available agent for increasing HDL cholesterol, and its effects are also additive to those of statins. Other agents that increase HDL cholesterol include thiazolidinediones, estrogen, and omega-3 fatty acids. The mechanisms by which nonstatin pharmacologic agents increase HDL cholesterol are not completely understood but probably involve multiple mechanisms for each class.

Hypercholesterolemia and Dyslipidemia: Issues for the Clinician

The current state of the art in the diagnosis and treatment of lipoprotein disorders has progressed beyond the standard "lipid profile," which includes total low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol, along with fasting triglycerides. Incorporating aspects of the atherogenic lipoprotein profile (ALP) (ALP and LDL subclass distribution), HDL subclass distribution, apolipoprotein E isoforms, lipoprotein (a), homocysteine, and high-sensitivity C-reactive protein provides the clinician with the tools to create a more detailed, accurate, and personalized diagnosis of disorders contributing to coronary artery disease in their patients. Sophisticated laboratory tests are available to clinicians through technology transfer programs as exemplified by the Lawrence Berkeley National Laboratory/Berkeley HeartLab, Berkeley, CA, collaboration and allow clinicians access to research quality laboratory tools. This has significant clinical relevance because the presence of these disorders guides treatment that is specific to the disorder(s). Appropriate treatment has been shown to have significantly greater clinical benefit in patient subgroups exhibiting the disorder the therapy is most likely to correct. A single drug or lifestyle therapy plan is no longer appropriate for all patients. The treatment must match the individual disorder(s).

Efficacy and safety of a novel cholesteryl ester transfer protein inhibitor, JTT-705, in humans: a randomized phase II dose-response study

BACKGROUND

Cholesteryl ester transfer protein (CETP) mediates the transfer of neutral lipids between lipoproteins. High plasma levels of CETP are correlated with low HDL cholesterol levels, a strong risk factor for coronary artery disease. In earlier studies, JTT-705, a novel CETP inhibitor, was shown to increase plasma HDL cholesterol and to inhibit the progression of atherosclerosis in cholesterol-fed rabbits. This study describes the first results using this CETP inhibitor in humans.

METHODS AND RESULTS

In a randomized, double-blind, and placebo-controlled trial, we evaluated the efficacy and safety of daily treatment with 300, 600, and 900 mg JTT-705 in 198 healthy subjects with mild hyperlipidemia. Treatment with 900 mg JTT-705 for 4 weeks led to a 37% decrease in CETP activity (P<0.0001), a 34% increase in HDL cholesterol (P<0.0001), and a 7% decrease in LDL cholesterol (P=0.017), whereas levels of triglycerides, phospholipid transfer protein, and lecithin-cholesterol acyltransferase were unaffected. In line with the increase of total HDL, a rise of HDL2, HDL3, and apolipoprotein A-I was also noted. JTT-705 showed no toxicity with regard to physical examination and routine laboratory tests.

CONCLUSIONS

We show that the use of the CETP inhibitor JTT-705 in humans is an effective means to raise HDL cholesterol levels with minor gastrointestinal side effects (P=0.06). Although these results hold promise, further studies are needed to investigate whether the observed increase in HDL cholesterol translates into a concomitant reduction in coronary artery disease risk.

Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL

One strategy for treating coronary artery disease (CAD) patients with low HDL cholesterol (HDL-C) is to maximally increase the HDL-C to LDL-C ratio by combining lifestyle changes with niacin (N) plus a statin. Because HDL can prevent LDL oxidation, the low-HDL state also may benefit clinically from supplemental antioxidants. Lipoprotein changes over 12 months were studied in 153 CAD subjects with low HDL-C randomized to take simvastatin and niacin (S-N), antioxidants (vitamins E and C, beta-carotene, and selenium), S-N plus antioxidants (S-N+A), or placebo. Mean baseline plasma cholesterol, triglyceride, LDL-C, and HDL-C levels of the 153 subjects were 196, 207, 127, and 32 mg/dL, respectively. Without S-N, lipid changes were minor. The S-N and S-N+A groups had comparably significant reductions (P</=0.001) in plasma cholesterol, triglyceride, and LDL-C. However, increases in HDL-C, especially HDL(2)-C, were consistently higher in the S-N group than in the S-N+A group (25% vs 18% and 42% vs 0%, respectively). With S-N, but not with S-N+A, there was a selective increase in apolipoprotein (apo) A-I (64%) in HDL particles containing apo A-I but not A-II [Lp(A-I)] and their particle size. Thus, in CAD patients with low HDL-C, S-N substantially increased HDL(2)-C, Lp(A-I), and HDL particle size. These favorable responses were blunted by the antioxidants used owing to a striking selective effect on Lp(A-I). This unexpected adverse interaction between antioxidants and lipid therapy may have important implications for the management of CAD.

Vaccine-induced antibodies inhibit CETP activity in vivo and reduce aortic lesions in a rabbit model of atherosclerosis

Using a vaccine approach, we immunized New Zealand White rabbits with a peptide containing a region of cholesteryl ester transfer protein (CETP) known to be required for neutral lipid transfer function. These rabbits had significantly reduced plasma CETP activity and an altered lipoprotein profile. In a cholesterol-fed rabbit model of atherosclerosis, the fraction of plasma cholesterol in HDL was 42% higher and the fraction of plasma cholesterol in LDL was 24% lower in the CETP-vaccinated group than in the control-vaccinated group. Moreover, the percentage of the aorta surface exhibiting atherosclerotic lesion was 39.6% smaller in the CETP-vaccinated rabbits than in controls. The data reported here demonstrate that CETP activity can be reduced in vivo by vaccination with a peptide derived from CETP and support the concept that inhibition of CETP activity in vivo can be antiatherogenic. In addition, these studies suggest that vaccination against a self-antigen is a viable therapeutic strategy for disease management.

Current perspectives on the management of hypertriglyceridemia

BACKGROUND

Observational studies have demonstrated that triglycerides are an independent risk factor for coronary heart disease. Atherothrombosis may be mediated by uptake and incorporation of triglyceride-rich lipoproteins by macrophages and through an association with small, dense LDL and HDL particles. There are considerable data that lowering LDL cholesterol reduces cardiovascular events. However, the importance of triglyceride lowering remains elusive.

METHODS

A summary of major arteriographic and clinical end point trials is reviewed. Studies evaluating various strategies, including dietary and hygienic measures as well as pharmacologic therapies, are discussed.

RESULTS

Dietary reduction of saturated fat, coupled with aerobic activity, reduces triglyceride levels approximately 20% to 24%. Omega-3 fatty acids may also reduce triglyceride levels appreciably. Effective pharmacologic therapies that lower triglyceride levels include nicotinic acid (20% to 40%), fibrates (20% to 55%), and statins (10% to 30%). Nevertheless, an independent benefit of triglyceride lowering on coronary event rate has not been demonstrated.

CONCLUSIONS

There are little data that triglyceride reduction improves cardiovascular event rate. In contrast, lowering LDL cholesterol and, more recently, raising HDL cholesterol are proven therapies in coronary heart disease prevention. As such, these modalities remain the top priority in the management of dyslipidemia with triglyceride reduction as an adjunctive consideration.

Hypercholesterolemia and Dyslipidemia

Disorders of cholesterol and lipoprotein metabolism are at the heart of atherosclerosis and coronary artery disease (CAD). CAD, however, is a metabolic disorder that involves a complex interaction between genetic susceptibility and environmental conditions. Despite considerable success in the treatment of hypercholesterolemia, atherosclerosis remains the leading cause of death in most Western countries. Although cholesterol-lowering trials have revealed a 25% to 30% reduction in clinical events, most patients continue to have events even when treated successfully with cholesterol-lowering medications (Fig. 1). This less-than-optimal result is partly because atherosclerosis is a multifactorial disease. Although disorders of lipoprotein metabolism are found in more than 80% of patients with CAD, these disorders are very heterogeneous, and single-drug therapy aimed at one disorder should not be expected to improve the disease status in most patients. Metabolic treatment still requires identification and treatment of patients with high cholesterol levels, but the focus has shifted to identifying high-risk patients in groups previously thought to be low risk, or to identifying disorders coexistent with high cholesterol levels that are not corrected by standard cholesterol-lowering medications (Table 1). The ability to detect high-risk CAD traits, which are often inherited, and to predict response to treatment has substantially improved in the past few years. These improvements allow identification of metabolic subgroups of patients, which can alter risk prediction and response to specific treatments. Sophisticated laboratory methods permit physicians to apply this knowledge to patient care and to enter a new era of CAD risk factor detection and treatment. These advances allow for a more scientific approach than did the previously standard epidemiologic risk factors and routine blood lipid profiles. The current state-of-the-art method of diagnosing and treating lipoprotein disorders has progressed beyond the standard "lipid profile," which includes total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol along with fasting triglyceride levels. Incorporating aspects of the atherogenic lipid profile (ALP), LDL subclass distribution, HDL subclass distribution, apo E isoforms, and lipoprotein (a) provides the interested clinician with the tools to create a more detailed and accurate diagnosis of lipoprotein disorders. Sophisticated laboratory tests are available to clinicians through technology transfer programs, as exemplified by the Lawrence Berkeley National Laboratory/Berkeley HeartLab collaboration, and allow clinicians access to research-quality laboratory tools. This has significant clinical relevance because the presence of these disorders guides treatment specific to the disorder(s). Appropriate treatment is more beneficial in subgroups exhibiting the disorder that the therapy is most likely to correct. A single drug or lifestyle therapy is no longer appropriate for all patients. The treatment must match the disorder.

Gemfibrozil, nicotinic acid and combination therapy in patients with isolated hypoalphalipoproteinemia: a randomized, open-label, crossover study

OBJECTIVES

To assess the effects of nicotinic acid (NA), gemfibrozil and combination therapy on the lipid profile of patients with clinical atherosclerotic disease and isolated hypoalphalipoproteinemia.

BACKGROUND

Isolated hypoalphalipoproteinemia (low high density lipoprotein cholesterol [HDL-C] alone) accounts for a significant percentage of patients with premature atherosclerosis. However, it remains unclear whether currently available pharmacotherapy has the ability to favorably affect the lipid profile and therefore potentially reduce clinical events.

METHODS

Twenty-three patients with clinically well-defined atherosclerosis and isolated hypoalphalipoproteinemia were prospectively randomized to receive gemfibrozil, NA or combination therapy in an open-label, crossover design trial to assess the effects on serum lipids. Lipid profiles and other relevant laboratory variables were monitored while the patients were on and off pharmacologic lipid-modulating therapy.

RESULTS

In those 14 patients able to tolerate all forms of pharmacotherapy, HDL-C of 0.89 +/- 0.17 mmol/liter (34.5 +/- 6.5 mg/dl) increased by 15%, to 1.02 +/- 0.18 mmol/liter (39.7 +/- 7.1 mg/dl), while taking gemfibrozil (1,200 mg/day); by 35%, to 1.20 +/- 0.21 mmol/liter (46.5 +/- 8.1 mg/dl), while taking NA (mean dose 2,250 mg/day); and by 45%, to 1.29 +/- 0.19 mmol/liter (50.0 +/- 7.5 mg/dl), while taking combination therapy of gemfibrozil plus NA (p < 0.001 for all interventions as compared with baseline/washout; p < 0.005 NA vs. gemfibrozil; p < 0.001 combination therapy vs. gemfibrozil alone; p = 0.088 combination therapy vs. NA alone). Statistically significant favorable alterations were also observed with low density lipoprotein cholesterol (LDL-C), LDL-C/HDL-C, non-HDL-C/HDL-C, apolipoprotein (Apo) B and Apo B/Apo A1.

CONCLUSIONS

In the majority of patients with clinical atherosclerotic disease and isolated hypoalphalipoproteinemia, pharmacologic therapy to raise HDL-C is not only feasible but is also effective with currently available agents, particularly when used in combination.

New developments in the treatment of low high-density lipoprotein cholesterol

Reduced levels of high-density lipoprotein (HDL) cholesterol represent an important risk factor for the development and progression of coronary artery disease. In recent years, clinical outcome studies have verified that statin therapy may reduce the risk of initial or recurrent cardiovascular events in subjects with elevated or "normal" cholesterol levels. Subgroup analysis has also revealed that patients with low HDL benefit from this therapy. Two recently presented outcome trials using fibrate therapy also demonstrated a potential role for these medications in subjects with low HDL. The use of various HDL raising agents, singly or in combination on arteriographic progression and their potential mechanisms of action are reviewed. The latter may be an important consideration in the treatment of high-risk patients with low HDL.

Small, dense low-density lipoprotein subclass pattern B: issues for the clinician

A large portion of coronary artery disease (CAD) can be attributed to disorders of lipoprotein metabolism. However, these disorders are a complex interaction of genetic susceptibility and environmental interaction. The most common disorder of lipoprotein metabolism contributing to CAD is the Small, Dense Low-Density Lipoprotein Pattern B disorder, also known as the Atherogenic Lipoprotein Profile (ALP), which consists of multiple metabolic disorders. This disorder is an independent risk factor for CAD and in patients with established CAD, identifies a subgroup with a twofold greater rate of arteriographic progression compared with CAD patients without this disorder. Treatment of the disorder is specific to lifestyle and some pharmacologic agents. The most effective treatments are often the least expensive.

Effectiveness of once-nightly dosing of extended-release niacin alone and in combination for hypercholesterolemia

We performed a multicenter, open-label study to determine the long-term safety and efficacy of a new extended-release once-a-night niacin preparation, Niaspan, in the treatment of hypercholesterolemia. Niaspan, 0.5 to 3.0 g once a night at bedtime, was used alone or in combination with a statin (inhibitor of hydroxymethylglutaryl coenzyme A reductase), a bile acid sequestrant, or both. Patients included 269 hypercholesterolemic male and female adults enrolled in a 96-week study, and 230 additional adults for whom short-term safety data were available. The dosages of Niaspan attained by 269 patients were 1,000 mg (95% of patients), 1,500 mg (86%), and 2,000 mg (65%). After 48 weeks of treatment, Niaspan alone (median dose 2,000 mg) reduced low-density lipaprotein (LDL) cholesterol (18%), apolipoprotein B (15%), total cholesterol (11%), triglycerides (24%), and lipoprotein(a) (36%), and increased high-density lipoprotein (HDL) cholesterol (29%). Niaspan plus a statin lowered LDL cholesterol (32%), apolipoprotein B (26%), total cholesterol (23%), triglycerides (30%), and lipoprotein(a) (19%), and increased HDL cholesterol (26%). Reversible elevations of aspartate aminotransferase or alanine aminotransferase more than twice the normal range occurred in 2.6% of patients. One patient discontinued Niaspan because of transaminase elevations. Intolerance to flushing, leading to discontinuation of Niaspan, occurred in 4.8% of patients. The overall rate of discontinuance due to flushing in this study combined with 2 previous randomized trials was 7.3%. In the long-term treatment of hypercholesterolemia, Niaspan produced favorable changes in LDL and HDL cholesterol, triglycerides, and lipoprotein(a). Adverse hepatic effects were minor and occurred at rates similar to those reported for statin therapy.

"Isolated" low high-density lipoprotein cholesterol

OBJECTIVE

To present information on the function, structure, and importance of high-density lipoprotein cholesterol (HDL-C) and to evaluate the current literature regarding the controversy of managing patients with an "isolated" low HDL-C concentration.

DATA SOURCE

A MEDLINE search was performed (1966-June 1996) to identify English-language clinical and review articles pertaining to HDL-C. Some articles were identified through the bibliography of selected articles. STUDY SECTION: All articles were considered for possible inclusion in the review. Pertinent information, as judged by the authors, was selected for discussion.

DATA EXTRACTION

Important historical lipid studies, recent review articles, and clinical trials involving therapy for HDL-C were evaluated.

DATA SYNTHESIS

The structure, function, and measurement of HDL-C and the state of an isolated low HDL-C are discussed for background. Lifestyle modification measures to increase HDL-C, medications to avoid, estrogen replacement, and lipid-altering agents used to raise an isolated low HDL-C are presented.

CONCLUSIONS

An isolated low HDL-C concentration poses a risk for coronary heart disease. The management of this state is controversial. The first step in management is in agreement with experts and includes lifestyle modification (e.g., weight reduction, diet, smoking cessation, aerobic exercise). Estrogen replacement therapy and discontinuance of drugs that secondarily lower HDL-C are additional treatment options. The use of lipid-altering agents has been used in some patients. Nicotinic acid appears to be an effective agent for an isolated low HDL-C. A large clinical trial evaluating the effect of treating an isolated low HDL-C for primary and secondary prevention of coronary events is needed.

Lipid management: current diet and drug treatment options

Diet and drug therapy are two of the principal approaches to lipid management. The aim of both is to reduce low-density-lipoprotein (LDL) cholesterol to goal levels established by the National Cholesterol Education Program Expert Panel in its second report, based on a patient's short-term risk of a coronary event. In prescribing diet therapy, it is important to determine patients' willingness to initiate and adhere to dietary modifications, their skill at reading nutritional labels, adapting recipes, and ordering "heart-healthy" foods when eating out. Diet therapy should be directed at modifying dietary factors known to adversely influence blood cholesterol-saturated fats, cholesterol, and obesity. Diet therapy (with exercise) is not always adequate. High risk individuals with no overt coronary artery disease but with >/=2 risk factors, as well as patients with coronary artery disease, are potential candidates for drug therapy, depending on their LDL cholesterol levels. The "statins" are the drug of choice for patients with coronary disease and elevated LDL cholesterol or familial LDL-cholesterol abnormalities. These drugs increase high-density-lipoprotein (HDL) cholesterol and reduce LDL cholesterol, coronary artery disease, and total mortality. Bile acid resins lower LDL cholesterol and are often used to augment the effects of the statins and niacin. Niacin is particularly useful in the management of patients with combined hyperlipidemia and low HDL cholesterol levels. Gemfibrozil is effective in familial dysbetalipoproteinemia and is the drug of choice for patients with severely elevated serum triglycerides.

A prospective, randomized trial of phenytoin in nonepileptic subjects with reduced HDL cholesterol

Observational studies have demonstrated a positive association between phenytoin use and HDL cholesterol (HDL-C). Our goal was to determine whether phenytoin raises HDL-C in nonepileptic subjects at risk for coronary artery disease. We performed a double-blind, placebo-controlled, parallel-group study in 41 subjects with reduced levels of HDL-C. Subjects were placed on an American Heart Association Step I diet and were randomized to receive either phenytoin or placebo for 3 months. Serum levels of phenytoin were monitored and adjusted to between 7.5 and 15 micrograms/mL. Fasting levels of lipids and lipoproteins were determined twice at baseline (weeks -2 and -1) and during the treatment phase of the study (weeks 11 and 12). Compared with dietary baseline, phenytoin-treated subjects experienced significant paired percent increases in total HDL-C (12.4%; P < .01), an effect confined to the HDL2 subfraction (137%; P < .01). The paired percent increases in HDL-C and HDL2 levels remained significant after adjustment for placebo (P < .05, P < .025, respectively). There were no significant differences in the paired percent changes from dietary baseline in total cholesterol, triglyceride, or LDL cholesterol levels between placebo and phenytoin-treated groups. The significant paired percent increases in total HDL-C and HDL2 from dietary baseline suggest a potential role for phenytoin in subjects with reduced levels of HDL-C.

Difficulty accepting lifestyle limitations after the abrupt onset of end-stage renal disease

Adjustment to the lifestyle changes imposed by end-stage renal disease is particularly difficult when the onset is abrupt and unheralded. A case of atheroembolism is presented in which living situation, dietary compliance, and family involvement are particularly problematic for the dialysis staff. Discussion by team members focuses on the evolution of a reasonable disposition through diligence and persistence, recognizing the need to compromise medical indications with individual lifestyle and available family support.