Evaluation of the effectiveness of lipid-lowering therapy (bile acid sequestrants, niacin, psyllium and lovastatin) for treating hypercholesterolemia in veterans

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.

Cholesterol reduction using psyllium husks - do gastrointestinal adverse effects limit compliance? Results of a specific observational study

PURPOSE

Despite known cholesterol lowering effects the use of psyllium husk (Plantaginis ovatae testa) in Germany for hypercholesterolemia is limited compared to their use as a laxative. To investigate whether use in hypercholesterolemia is limited due to adverse effects on the gastrointestinal system, a prospective observational study was conducted.

METHODS

Sixty-two outpatients with documented hypercholesterolemia and complaints of constipation were identified from an academic clinical center. Treatment with 3.5g psyllium husk preparation administered three times daily was initiated and patients were monitored at weekly intervals. Gastrointestinal symptoms were quantified using a validated Nepean Dyspepsia Index modified to identify both upper and lower abdominal symptoms. Diaries and study medication records were used to evaluate compliance.

RESULTS

Fifty-four of 62 patients enrolled in the study completed the study protocol with 4 subjects discontinuing due to adverse reactions associated with psyllium husks. Total cholesterol was significantly decreased from 252+/-39mg/dl before treatment to 239+/-37mg/dl after 3 weeks of treatment. Similarly, low density lipoprotein (LDL)-cholesterol decreased from 174+/-34 to 162+/-31mg/dl during the study. Triglycerides and high density lipoprotein (HDL) were unchanged. Gastrointestinal symptoms were rated lower at the end than at the beginning of the study. In week 1 most of the patients reported gastrointestinal symptoms and also gastrointestinal adverse reactions, which however, showed a decrease from week 1 to weeks 2 and 3 in the diaries. Patient response to study medication was positive for patients completing the study.

CONCLUSIONS

Psyllium husk preparations may be a therapeutic option for patients with mild to moderately elevated cholesterol levels. Adverse gastrointestinal symptoms associated with the preparation appear to be transient in some of the patients. Compliance may be optimized with adequate patient counseling.

Clinical evidence for use of acetyl salicylic acid in control of flushing related to nicotinic acid treatment

Nicotinic acid (NA) is highly effective and widely used in the management of dyslipidaemia. For many patients, the side effect of flushing of the face and upper body leads to discontinuation. Flushing with NA is mediated by prostaglandins, and as acetyl salicylic acid (ASA, 'aspirin') is a highly effective inhibitor of prostaglandin synthesis, there is a rationale for its use to prevent or reduce the severity of NA-related flushing. This literature survey identified four studies specifically exploring the utility of ASA in preventing NA-related flushing in healthy volunteers. Twenty-three NA studies, where ASA was mandatory or optional within the protocol, and four studies, where background ASA therapy was reported in most participants, were also identified. Although the incidence of flushing in studies using ASA was often high, discontinuation rates due to flushing were low (mean 7.7%). This figure compares favourably with discontinuation rates with NA commonly reported in the literature (up to approximately 40%). There is good supportive evidence for the use of ASA in reducing the severity of NA-related flushing.

Optimal management of hyperlipidemia in primary prevention of cardiovascular disease

Cardiovascular disease (CVD) in the developed countries continues to grow at an epidemic proportion. There are a significant number of young adults with no clinical evidence of CVD, but who have two or more risk factors that predispose them to CV events and death. Many of these risk factors are modifiable, and by controlling these factors, the CVD burden can be decreased significantly. Recent statistics have shown that, if all major forms of CVD were eliminated, the life expectancy would rise by almost 7 years. Hence it is imperative that primary prevention efforts should be initiated at a young age to avert decades of unattended risk factors. Hyperlipidemia has been linked to CVD almost a century ago. Since then various clinical trials have not only supported this link, but have also shown the CV benefits in aggressively treating patients with hyperlipidemia. In this generation, we have various therapeutic agents that are capable of reducing the elevated lipid levels. With drugs like statins, we are able to reduce the risk of CVD by about 30% and avoid major adverse events. Newer drugs are being researched and introduced in the treatment of hyperlipidemia in humans. These can be used in combination therapy resulting in optimal levels of lipids. The new National Cholesterol Education Program (NCEP)/Adult Treatment Panel III (ATP III) guidelines have come as a wake-up call to clinicians about primary prevention of CVD through strict lipid management and multifaceted risk management approach in the prevention of CVD.

Effect of time of administration on cholesterol-lowering by psyllium: a randomized cross-over study in normocholesterolemic or slightly hypercholesterolemic subjects

Background

Reports of the use of psyllium, largely in hypercholesterolemic men, have suggested that it lowers serum cholesterol as a result of the binding of bile acids in the intestinal lumen. Widespread advertisements have claimed an association between the use of soluble fibre from psyllium seed husk and a reduced risk of coronary heart disease. Given the purported mechanism of cholesterol-lowering by psyllium, we hypothesized that there would be a greater effect when psyllium is taken with breakfast than when taken at bedtime. Secondarily, we expected to confirm a cholesterol-lowering effect of psyllium in subjects with "average" cholesterol levels.

Methods

Sixteen men and 47 women ranging in age from 18 to 77 years [mean 53 +/- 13] with LDL cholesterol levels that were normal or slightly elevated but acceptable for subjects at low risk of coronary artery disease were recruited from general gastroenterology and low risk lipid clinics. Following a one month dietary stabilization period, they received an average daily dose of 12.7 g of psyllium hydrophilic mucilloid, in randomized order, for 8 weeks in the morning and 8 weeks in the evening. Change from baseline was determined for serum total cholesterol, LDL, HDL and triglycerides.

Results

Total cholesterol for the "AM first" group at baseline, 8 and 16 weeks was 5.76, 5.77 and 5.80 mmol/L and for the "PM first" group the corresponding values were 5.47, 5.61 and 5.57 mmol/L. No effect on any lipid parameter was demonstrated for the group as a whole or in any sub-group analysis.

Conclusion

The timing of psyllium administration had no effect on cholesterol-lowering and, in fact, no cholesterol-lowering was observed. Conclusions regarding the effectiveness of psyllium for the prevention of heart disease in the population at large may be premature.

Patient adherence and medical treatment outcomes: a meta-analysis

BACKGROUND

Adherence is a factor in the outcome of medical treatment, but the strength and moderators of the adherence-outcome association have not been systematically assessed.

OBJECTIVES

A quantitative review using meta-analysis of three decades of empirical research correlating adherence with objective measures of treatment outcomes.

METHOD

Sixty-three studies assessing patient adherence and outcomes of medical treatment were found involving medical regimens recommended by a nonpsychiatrist physician, and measuring patient adherence and health outcomes. Studies were analyzed according to disease (acute/chronic, severity), population (adult/child), type of regimen (preventive/treatment, use of medication), and type and sensitivity of adherence and outcomes measurements.

RESULTS

Overall, the outcome difference between high and low adherence is 26%. According to a stringent random effects model, adherence is most strongly related to outcomes in studies of nonmedication regimens, where measures of adherence are continuous, and where the disease is chronic (particularly hypertension, hypercholesterolemia, intestinal disease, and sleep apnea). A less stringent fixed effects model shows a trend for higher adherence-outcome correlations in studies of less serious conditions, of pediatric patients, and in those studies using self-reports of adherence, multiple measures of adherence, and less specific measures of outcomes. Intercorrelations among moderator variables in multiple regression show that the best predictor of the adherence-outcome relationship is methodological-the sensitivity/quality of the adherence assessment.

Effect of very-low-dose niacin on high-density lipoprotein in patients undergoing long-term statin therapy

BACKGROUND

A low level of high-density lipoprotein (HDLC) is a proven risk factor for coronary artery disease. Niacin raises HDLC levels, but it is infrequently used because of its side effect profile. Niacin's side effects are dose related. This study tests the hypothesis that very low-dose niacin, in conjunction with long-term statin therapy, will improve the lipid profile by significantly raising the level of HDLC, with fewer side effects than traditional doses of niacin.

METHODS

Fifty patients undergoing stable statin therapy for 3 months were blindly randomized to receive either placebo or niacin 50 mg administered by mouth 2 times daily for 3 months. Patients with diabetes and active smokers were excluded. Each patient completed a questionnaire regarding current medical problems, medications, and lifestyle before and after the therapy. Patients were questioned about any possible side effects that occurred during the medication trial. The primary end points were change in HDLC level and patient-reported side effects.

RESULTS

Thirty-nine patients completed the study. Very low-dose niacin added to statin therapy increased the mean HDLC, 2.1 mg/dL in niacin group (standard error of the mean, 0.767) versus -0.56 mg/dL for placebo group (standard error of the mean-.816, P =.0246 by analysis of variance). Five patients receiving niacin, versus 2 patients receiving placebo, had episodes of flushing. No major side effects were noted. No patients stopped the study medication as a result of side effects.

CONCLUSIONS

The addition of very low-dose niacin to statin therapy increased HDLC cholesterol significantly, while avoiding the side effects that are associated with traditional doses of niacin therapy.

Absorption of colesevelam hydrochloride in healthy volunteers

OBJECTIVE

To assess whether colesevelam hydrochloride is absorbed in healthy volunteers.

METHODS

A single-center, open-label, radiolabeled study was performed with 16 healthy volunteers. Subjects were administered non-radiolabeled colesevelam hydrochloride 1.9 g twice daily for 4 weeks, followed by a single dose of [14C]-colesevelam 2.4 g (480 pCi). These subjects continued to receive non-radioactive colesevelam 1.9 g twice daily for 4 days after administration of the radiolabeled dose. Blood, urine, and feces were collected immediately prior to administration of [14C]-colesevelam and at specified intervals after administration. The whole-blood equivalent concentration of colesevelam was calculated using data collected throughout the 96 hours following radiolabeled drug administration. The proportion of [14C]-colesevelam excreted through urine or feces was calculated based on the amount of radioactivity recovered up to 216 hours after the radiolabeled dose.

RESULTS

The mean cumulative total recovery of [14C]-colesevelam in urine and feces was 0.05% and 74%, respectively. Excluding 2 subjects for whom cumulative recovery was <25%, the mean cumulative fecal recovery was 82%. The mean maximum whole-blood equivalent concentration of colesevelam was 0.165+/-0.10 microg equiv/g 72 hours after administration of [14C]-colesevelam, which was estimated to be 0.04% of the administered dose. All blood samples contained <4 times the number of background counts (dpm).

CONCLUSIONS

The cumulative recovery data in urine and feces are consistent with the conclusion that colesevelam is not absorbed and is excreted entirely through the gastrointestinal system.

Poor adherence with hypolipidemic drugs: a lost opportunity

All articles assessing adherence to hypolipidemic drugs were reviewed and categorized by patient population (clinical trial, unselected) and reported as rates of nonadherence and discontinuation. Overall, levels of discontinuation reported in clinical trials (6-31%) and lipid clinics (2-38%) are similar, with unselected populations consistently reporting higher rates (15-78%). Rates of nonadherence in clinical trials and lipid clinics also are comparable, with unselected populations having the highest rates. Across all settings, rates of discontinuation and nonadherence are consistently reported to be poorer with resins and niacin than with hydroxy-6-methylglutamate coenzyme A reductase inhibitors. Adherence to hypolipidemic agents appears to decrease in parallel with level of follow-up. Data evaluating mechanisms of poor adherence are limited. While the search for new, efficacious therapies must continue, efforts focused on improving adherence to proven therapy may have a greater overall impact on health than any single new agent.

Effectiveness of colesevelam hydrochloride in decreasing LDL cholesterol in patients with primary hypercholesterolemia: a 24-week randomized controlled trial

OBJECTIVE

To evaluate the efficacy, tolerability, and safety of colesevelam hydrochloride, a new nonsystemic lipid-lowering agent.

PATIENTS AND METHODS

In this double-blind, placebo-controlled trial performed in 1998, 494 patients with primary hypercholesterolemia (low-density lipoprotein [LDL] cholesterol level > or = 130 mg/dL and < or = 220 mg/dL) were randomized to receive placebo or colesevelam (2.3 g/d, 3.0 g/d, 3.8 g/d, or 4.5 g/d) for 24 weeks. Fasting serum lipid profiles were measured to assess efficacy. Adverse events were monitored, and discontinuation rates and compliance rates were analyzed. The primary outcome measure was the mean absolute change of LDL cholesterol from baseline to the end of the 24-week treatment period.

RESULTS

Colesevelam lowered mean LDL cholesterol levels 9% to 18% in a dose-dependent manner (P<.001), with a median LDL cholesterol reduction of 20% at 4.5 g/d. The reduction in LDL cholesterol levels was maximal after 2 weeks and sustained throughout the study. Mean total cholesterol levels decreased 4% to 10% (P<.001), while median high-density lipoprotein cholesterol levels increased 3% to 4% (P<.001). Median triglyceride levels increased by 5% to 10% in placebo and colesevelam treatment groups relative to baseline (P<.05), but none of these differences were significantly different from placebo. Mean apolipoprotein B levels decreased 6% to 12% in an apparent dose-dependent manner (P<.001). No significant differences occurred in adverse events or discontinuation rates between groups, and compliance rates were between 88% and 92% for all groups.

CONCLUSIONS

Colesevelam was efficacious, decreasing mean LDL cholesterol levels by up to 18%, and well tolerated without serious adverse events.

Colesevelam hydrochloride: a novel bile acid-binding resin

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and adverse effects of colesevelam hydrochloride, a bile acid-binding resin.

METHODS

MEDLINE searches (1966-June 2000) and manufacturer prescribing literature were employed to find articles on colesevelam. Additional studies and abstracts were identified from the bibliographies of reviewed literature.

STUDY SELECTION AND DATA EXTRACTION

All articles identified from data sources were evaluated, and all information deemed relevant was included in this review. Priority was given to randomized, double-blind, placebo-controlled studies.

FINDINGS

Colesevelam HCl is a nonabsorbed hydrogel with bile acid sequestrant properties. Monotherapy using colesevelam in once-daily or two divided daily doses of 1.5-4.5 g has produced significant reductions in total cholesterol and low-density lipoprotein (LDL) cholesterol. Mean LDL cholesterol decreases to 20% have been noted when the patient is on 3.75-4.5 g/d. Increases in high-density lipoprotein (HDL) cholesterol have been observed (up to 9%), whereas triglycerides (TG) have increased significantly to 25% in some studies. In unpublished studies, combined use of colesevelam plus hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor have produced greater reductions in LDL cholesterol than either the statin or colesevelam administered alone. The efficacy of colesevelam monotherapy is slightly less than or similar to cholestyramine or colestipol in decreasing LDL cholesterol, although colesevelam is more potent on a gram-to-gram basis. Adverse effects have been minimal with colesevelam in published studies; this suggests an advantage over cholestyramine or colestipol therapy. Colesevelam appears to be more cost-effective than the packet dosage form of the brand formulation of the older bile acid resins. Care in selection of an appropriate agent should be exercised when considering the issues of adverse effects and palatability.

CONCLUSIONS

Colesevelam alone or combined with an HMG-CoA reductase inhibitor is effective in the reduction of total and LDL cholesterol. Since colesevelam is formulated as a tablet, problems with palatability such as with the powder formulation of the bile acid-binding resins are likely to be eliminated.

Combination drug therapy for dyslipidemia

Effective treatment of dyslipidemia improves prognosis. Statin therapy has been documented to decrease the cardiovascular event rate in the setting of elevated low-density lipoprotein (LDL) cholesterol levels and coronary heart disease, but most patients are not treated to the target (LDL <or=100 mg/dL) set by the National Cholesterol Education Program. The triglyceride level is also being increasingly recognized as an important mediator in the process of progressive atherosclerosis and cardiovascular events. Studies suggest the target level for triglycerides should be the same as for LDL cholesterol levels-- no more than 100 mg/dL. In order to achieve these LDL and triglyceride levels, combination therapy is required frequently. Probably the most effective combination for mixed dyslipidemia is a statin with niacin. The use of adjunctive omega-3 supplementation also should be considered especially for patients with elevated triglyceride levels. Other adjunctive agents including sitostanol ester (in the form of a margarine) and a well-tolerated second generation bile acid sequestrant that will lower LDL cholesterol an additional 10% to 18% and will be available soon.

What is happening in the real world in lipid therapy and is it appropriate? The need for a paradigm shift

Cardiovascular disease is now the leading cause of death and disability in our society. Current strategies in the United States have been very effective in treating the symptomatic manifestations of severe obstructions but have done little to alter the long-term outcome of cardiovascular disease. Although lipid-lowering therapies have proven beneficial in secondary prevention for patients with cardiovascular disease, they are not as widely employed in contemporary practice as they should be. Better implementation of lipid-lowering therapies, including such major issues as clear treatment guidelines, physician and patient compliance, and delivery of healthcare and quality of care, must be addressed to shift thinking about the treatment of cardiovascular disease as we advance into the next century.

Compliance in the real world

Until 1994, rates of noncompliance for lipid-lowering therapies were largely drawn from clinical trials and showed favorable risks for drug discontinuation, ranging from 4-15% for 1-year risk to 11-30% for 5-year risk. Although cross-study comparisons are difficult to make because of variations in study design and measures collected, when evaluating compliance to antihyperlipidemic drugs in primary care settings, results in general show substantially higher rates of discontinuation than those reported from randomized clinical trials. Recent studies from the United States, Australia, and Canada support the conclusion that adherence to lipid-lowering drugs is very poor in primary care settings.

Interaction between Potassium-Depleting Diuretics and Lovastatin in Hypercholesterolemic Ambulatory Care Patients

Objective:

To evaluate the potential impact of potassium-depleting diuretics on the efficacy of lovastatin.

Design:

A retrospective study of ambulatory patients taking lovastatin and thiazide or loop diuretics was conducted.

Setting:

Ambulatory care patients with coexisting hypercholesterolemia and hypertension from a Veterans Affairs Medical Center.

Participants:

A total of 32 patients were studied, 13 of whom had been taking lovastatin before diuretics were added. Another 19 patients had been receiving diuretics before lovastatin was initiated. The changes in their total cholesterol from baseline were recorded and analyzed.

Main Outcome Measures:

In all the patients taking lovastatin and diuretics concurrently, total cholesterol concentrations dropped initially, followed by a rise despite continuation of therapy with lovastatin. The reason for this initial drop in total cholesterol following 1 month of concurrent therapy is the subject of further investigation in a prospective study.

Results:

Regardless of the order of administration of the lipid-lowering and antihypertensive drugs, serum cholesterol rose 20% from its nadir.

Conclusions:

Patients taking potassium-depleting diuretics and a hepatic hydroxymethylglutaryl-coenzyme A reductase enzyme inhibitor (lovastatin) concurrently do not seem to benefit substantially from the lipid-lowering effect of lovastatin, probably because of a functional antagonism of the lipid-lowering effect of lovastatin by potassium-depleting diuretics.

Physician extenders for cost-effective management of hypercholesterolemia

OBJECTIVE

Treatment of elevated cholesterol levels reduces morbidity and mortality from coronary heart disease in high-risk patients, but can be costly. The purpose of this study was to determine whether physician extenders emphasizing diet modification and, when necessary, effective and inexpensive drug algorithms can provide more cost-effective therapy than conventional care.

DESIGN

Randomized controlled trial.

SETTING

A Department of Veterans Affairs Medical Center.

PATIENTS

Two hundred forty-seven veterans with type IIa hypercholesterolemia.

INTERVENTIONS

Patients assigned to either a cholesterol treatment program (CTP) or usual health care provided by general internists (UHC). CTP included intensive dietary therapy administered by a registered dietitian utilizing individual and group counseling and drug therapy initiated by physician extenders for those failing to achieve goal low-density lipoprotein (LDL) levels with diet alone. A drug selection algorithm for CTP subjects utilized niacin as initial therapy followed by bile acid sequestrants and lovastatin. Subjects were followed prospectively for 2 years.

MEASUREMENTS

Primary outcome measurements were effectiveness of therapy defined as reductions in LDL cholesterol (LDL-C), and whether goal LDL-C levels were achieved; costs of therapy; and cost-effectiveness defined as the cost per unit reduction in the LDL-C.

MAIN RESULTS

Total program costs were higher for CTP patients than for UHC patients ($659 +/- $43 vs $477 +/- $42 per patient, p < .001). However, at 24 months the patients in CTP were more likely to achieve LDL goal levels (65% vs 44%, p < .005), and also achieved greater reductions in LDL-C 27% +/- 2% vs 14% +/- 2% at 24 months, p < .001). Program costs per unit (mmol/L) reduction in the LDL-C, a measure of cost-effectiveness, was significantly lower for CTP ($758 +/- $58 vs $1,058 +/- $70, p = .002).

CONCLUSIONS

Although more expensive than usual care, the greater effectiveness of physician extenders implementing cholesterol treatment algorithms resulted in more cost-effective therapy.

Effective lovastatin therapy in elderly hypercholesterolemic patients — an antioxidative impact?

The effect of 3 months lovastatin therapy on serum lipids, apolipoproteins, alpha-tocopherol and red cell membrane fatty acid pattern was assessed in twelve elderly ambulatory patients (mean age 70.9+/-8.0 years) with hypercholesterolemia type IIa according to Fredrickson. After a run-in period of 4 weeks without drug therapy, the patients were given a daily dose of 20 mg lovastatin. The treatment resulted in statistically significant decreases in mean serum low density lipoprotein cholesterol (LDL-CH, -34%), in the atherogenic index LDL-CH/HDL-CH (-35%) and in the concentration of apolipoprotein B (-26%). No change in the vitamin E status, as related to plasma total lipids, was observed during the 3 months of therapy. The fatty acid pattern of phospholipids from red cell membranes showed an increase in linoleic acid metabolites and a decrease in the precursor linoleic acid, indicating an induction of fatty acid desaturases by lovastatin. In addition, an increase in the plasmalogen portion of erythrocyte membrane phospholipids was exhibited by increases in the proportion of fatty aldehyde dimethyl acetals (DMA) in the fatty acid pattern. The plasmalogens increase may counteract the slow but consistent decrease in their concentration in red cell membranes and human aortas with increasing donor age and in arteriosclerosis. Since plasmalogens may function as physiological antioxidants, the observed increase in DMA concentration might reflect a previously unrecognized antioxidative principle of a lovastatin therapy.

Drug therapy for hypercholesterolemia in patients with cardiovascular disease: factors limiting achievement of lipid goals

PURPOSE

To determine the extent that goal lipid levels derived from the National Cholesterol Education Program (NCEP) are achievable in clinical practice, and to identify factors associated with the achievement of these goals.

PATIENTS AND METHODS

We conducted a retrospective cohort study consisting of a consecutive sample of 244 patients with either coronary artery disease or peripheral vascular disease treated for hypercholesterolemia at a large Veterans Affairs medical center. Primary outcomes, recorded prospectively, were lipid levels and lipoprotein cholesterol response, and tolerance and compliance to drug therapy. Goal lipid levels were defined as low-density lipoprotein cholesterol (LDL-C) < or = 130 mg/dL and triglyceride (TG) < or = 200 mg/dL.

RESULTS

Lipid-lowering drug therapy reduced LDL-C from 25% to 42% below baseline in patients with hypercholesterolemia varying from mild (130 to 160 mg/dL) to severe ( > 220 mg/dL), respectively. Approximately 75% of patients with LDL-C < or = 160 mg/dL ultimately achieved their lipid goal with drug therapy; however, less than half of patients with baseline LDL-C > 160 mg/dL achieved target lipid values. Multivariate analysis indicated that lower baseline LDL-C and triglycerides, use of combinations of drug therapy rather than monotherapy, and patient adherence to treatment predicted the achievement of goal lipid levels.

CONCLUSIONS

Successful implementation of NCEP guidelines, frequently requires combination drug therapies, and is limited by poor patient tolerance and acceptance of niacin and the sequestrants.

Therapy with HMG CoA reductase inhibitors: characteristics of the long-term permanence of hypocholesterolemic activity

Treatment with hydroxymethylglutaryl coenzyme A (HMG CoA) reductase inhibitors has gained considerable success in the management of hypercholesterolemia. A large number of studies have shown the efficacy of these drugs in lowering plasma total and low density lipoprotein (LDL) cholesterol levels, but there have been less studies evaluating their effectiveness in standard clinical practice, particularly relating to the maintenance of hypocholesterolemic activity. In the present study, the long-term effectiveness of HMG CoA reductase inhibitors has been tested in 177 patients with familial hypercholesterolemia (FH) who had been on statin therapy (simvastatin or pravastatin) for at least 12 months and up to 5 years or longer. The mean 'dose normalized' LDL cholesterol reduction in the whole group was around 20%. However, in spite of a generally good efficacy of both statins in lowering total and LDL cholesterol, a wide variety of responses, either after short- or long-term treatment, was noted. Individual responses were calculated and patients classified into three different groups: (a) responders, (b) non-responders, and (c) response losers. Of the 177 patients, 4% did not respond to treatment and a further 10% showed an initial unsatisfactory response (LDL cholesterol reduction < or = 10%). Another 10% experienced a progressive loss of response over time. There appeared to be little difference between the two treatments in the long-term efficacy and no predictive index could be established. Treatment with HMG CoA reductase inhibitors is generally effective and well tolerated, but a non-negligible number of patients may show a primary non-response or a progressive loss of response.

Cholesterol in patients with coronary heart disease: how low should we go?

CLINICAL PROBLEM

To examine the evidence supporting the recent National Cholesterol Education Program (NCEP) recommendation that low to moderate levels of cholesterol should be aggressively managed in patients with coronary heart disease (CHD).

METHODS

Cohort studies and clinical trials with angiographic or clinical endpoints, that included CHD patients with low to moderate levels of cholesterol, were systematically identified through a MEDLINE search and critically reviewed.

SYNOPSIS

None of the cohort studies show that a moderate level of cholesterol confers significantly increased risk of CHD death, although a pooled relative risk of 1.14 (95% CI 1.08 to 1.4) suggests that there may be a slight excess risk. Of five angiographic trials of CHD patients with moderate levels of cholesterol, two demonstrated no improvement in angiographic endpoints with intensive lipid-lowering therapy and the other three are difficult to interpret since they included other interventions in addition to the cholesterol-lowering regimen. No large clinical trial with clinical endpoints has been reported for CHD patients with low to moderate levels of cholesterol.

RECOMMENDATIONS

The recommendation to treat CHD patients who have low to moderate levels of cholesterol with diet or drugs is not based on convincing evidence of efficacy. This is in clear contrast to the recommendation for CHD patients with high levels of cholesterol, for whom there is definitive clinical trial evidence of benefit from cholesterol-lowering therapy. While we await clinical trial results for CHD patients with low to moderate levels of cholesterol, clinicians and patients must consider the possible disadvantages of therapy in relation to the uncertain benefit.

Discontinuation of antihyperlipidemic drugs--do rates reported in clinical trials reflect rates in primary care settings?

BACKGROUND

Discontinuation rates for drugs used to treat chronic conditions may affect the success of therapy. However, the discontinuation rates reported in clinical trials may not reflect those in primary care settings.

METHODS

We conducted a cohort study using computerized research files and medical records on 2369 new users of antihyperlipidemic therapy at two health maintenance organizations (HMOs) from 1988 through 1990. The rates of drug discontinuation in these primary care settings were compared with the rates reported in clinical trials published from 1975 through 1993, located with the Medline data base.

RESULTS

In the HMOs, the one-year probability of drug discontinuation was 41 percent for bile acid sequestrants (95 percent confidence interval, 38 to 44 percent), 46 percent for niacin (95 percent confidence interval, 42 to 51 percent), 15 percent for lovastatin (95 percent confidence interval, 11 to 19 percent), and 37 percent for gemfibrozil (95 percent confidence interval, 31 to 43 percent). For the bile acid sequestrants, niacin, and gemfibrozil, the risks of discontinuation were substantially higher in the HMOs than in randomized clinical trials, in which the summary estimates of this risk were 31 percent, 4 percent, and 15 percent, respectively, for trials of one year or longer. The rates of discontinuation in open-label studies were similar to those in the HMOs.

CONCLUSIONS

The discontinuation rates reported in randomized clinical trials may not reflect the rates actually observed in primary care settings. The effectiveness and tolerability of antihyperlipidemic medications should be studied further in populations that typically use the agents.

Fluvastatin with and without niacin for hypercholesterolemia

Seventy-four patients with plasma low-density lipoprotein cholesterol levels > or = 160 mg/dl after an American Heart Association phase 1 diet were randomized to double-blind treatment with fluvastatin, 20 mg/day, or placebo for 6 weeks. Immediate-release niacin was then added to both treatment regimens and titrated to a maximum of 3 g/day for a further 9 weeks. After 6 weeks of fluvastatin monotherapy, low-density lipoprotein cholesterol levels decreased by 21% (p < 0.001 vs placebo), and after the addition of niacin, response was potentiated to 40% compared with 25% for the niacin control group at study end point (p < 0.001). Fluvastatin, alone and in combination with niacin, also significantly improved high-density lipoprotein cholesterol (increases of about 30%) and triglyceride profiles (decreases of approximately 28%) from baseline. Lipoprotein(a) decreased by 37% in those receiving fluvastatin-niacin but was unaltered in those receiving fluvastatin alone. No serious adverse events were ascribed to fluvastatin, and no cases of myositis were observed. Small, transient, asymptomatic increases in aspartate aminotransferase were noted with fluvastatin-niacin treatment but were not considered clinically relevant. Although the fluvastatin-niacin combination in this study was without evidence of significant transaminitis, myopathy, or rhabdomyolysis, it would seem prudent to continue to monitor its safety with longer term use. In conclusion, fluvastatin, both as monotherapy and in combination with niacin, proved to be an effective, safe, and well-tolerated therapeutic alternative for hypercholesterolemia.

Management of older adults with hypercholesterolaemia

Although the strength of total cholesterol levels as a relative risk factor for coronary heart disease (CHD) declines with age, the prevalence of CHD increases dramatically with age. Data from cholesterol treatment trials, although sparse in older adults, suggest that dyslipidaemia treatment has the potential to prevent CHD. In particular, dyslipidaemia treatment appears to be most beneficial in older adults with a history of CHD or who have several other CHD risk factors. Dyslipidaemia screening should be selective in the elderly, reserved for those whose health status would be amenable to nutritional or pharmacological therapy, and in whom several CHD risk factors or a history of CHD are present. Since high density lipoprotein cholesterol (HDL) levels retain their inverse association CHD in old age, cholesterol subfractions should be measured in persons being screened in order to adequately assess the severity of dyslipidaemia. Treatment decisions should be guided by the patient's dyslipidaemic class, which is determined by the cholesterol subfractions and serum triglycerides (TG). As in younger persons, nutritional therapy remains the first step in dyslipidaemia management in high risk, nondebilitated older adults. An array of cholesterol modifying medications are available which vary widely in treatment effects, adverse effects and cost. Extra care needs to be taken in prescribing these agents in older adults because of greater potential for adverse effects and interactions with other medications. The cost-effectiveness of pharmacological treatment decreases with age and increases with the severity of dyslipidaemia, a history of CHD, or the presence of multiple CHD risk factors. When comparing elderly to middle-aged adults, the relative cost-effectiveness of different cholesterol-lowering medications may be altered due to age-related changes in therapeutic efficacy and adverse effects.

Telephone contacts do not improve adherence to niacin or bile acid sequestrant therapy

OBJECTIVE

Noxious adverse effects frequently limit patient acceptance of niacin and bile acid sequestrants (BAS), first-line agents in the management of hypercholesterolemia. The purpose of this study was to determine whether telephone contacts from a healthcare professional could improve drug adherence and tolerance in patients prescribed these medications.

PATIENTS AND METHODS

This was a randomized, single-blind trial of telephone contacts vs. no intervention in patients with hyperlipidemia who were prescribed either niacin or BAS in a large, Veterans Affairs, lipid clinic. Patients randomized to telephone contact (n = 81) received weekly calls from a trained healthcare professional during the first month of drug therapy. Counseling regarding adverse effects, and prescriptions to overcome minor adverse effects, were provided as needed to patients during the telephone contact.

RESULTS

Significant differences were not observed between groups in the drug discontinuance rate, adherence assessed by two independent methods, or in the final dosage of medication ingested.

CONCLUSIONS

Telephone contacts do not improve either adherence or tolerance to niacin or BAS. Alternative approaches to enhance acceptance of these medications requires further evaluation.