Compliance with and efficacy of treatment with pravastatin and cholestyramine: a randomized study on lipid-lowering in primary care

Disparities in patterns and outcomes of dyslipidemic patients with acute coronary syndrome: A tertiary cardiac center registry

Graphical Abstract: Dyslipidemia Patterns in Patients with Acute Coronary Syndrome.Image 1.

Prevalence of statin intolerance: a meta-analysis

AIMS

Statin intolerance (SI) represents a significant public health problem for which precise estimates of prevalence are needed. Statin intolerance remains an important clinical challenge, and it is associated with an increased risk of cardiovascular events. This meta-analysis estimates the overall prevalence of SI, the prevalence according to different diagnostic criteria and in different disease settings, and identifies possible risk factors/conditions that might increase the risk of SI.

METHODS AND RESULTS

We searched several databases up to 31 May 2021, for studies that reported the prevalence of SI. The primary endpoint was overall prevalence and prevalence according to a range of diagnostic criteria [National Lipid Association (NLA), International Lipid Expert Panel (ILEP), and European Atherosclerosis Society (EAS)] and in different disease settings. The secondary endpoint was to identify possible risk factors for SI. A random-effects model was applied to estimate the overall pooled prevalence. A total of 176 studies [112 randomized controlled trials (RCTs); 64 cohort studies] with 4 143 517 patients were ultimately included in the analysis. The overall prevalence of SI was 9.1% (95% confidence interval 8.0-10%). The prevalence was similar when defined using NLA, ILEP, and EAS criteria [7.0% (6.0-8.0%), 6.7% (5.0-8.0%), 5.9% (4.0-7.0%), respectively]. The prevalence of SI in RCTs was significantly lower compared with cohort studies [4.9% (4.0-6.0%) vs. 17% (14-19%)]. The prevalence of SI in studies including both primary and secondary prevention patients was much higher than when primary or secondary prevention patients were analysed separately [18% (14-21%), 8.2% (6.0-10%), 9.1% (6.0-11%), respectively]. Statin lipid solubility did not affect the prevalence of SI [4.0% (2.0-5.0%) vs. 5.0% (4.0-6.0%)]. Age [odds ratio (OR) 1.33, P = 0.04], female gender (OR 1.47, P = 0.007), Asian and Black race (P < 0.05 for both), obesity (OR 1.30, P = 0.02), diabetes mellitus (OR 1.26, P = 0.02), hypothyroidism (OR 1.37, P = 0.01), chronic liver, and renal failure (P < 0.05 for both) were significantly associated with SI in the meta-regression model. Antiarrhythmic agents, calcium channel blockers, alcohol use, and increased statin dose were also associated with a higher risk of SI.

CONCLUSION

Based on the present analysis of >4 million patients, the prevalence of SI is low when diagnosed according to international definitions. These results support the concept that the prevalence of complete SI might often be overestimated and highlight the need for the careful assessment of patients with potential symptoms related to SI.

A Meta-Analysis Assessing Additional LDL-C Reduction from Addition of a Bile Acid Sequestrant to Statin Therapy

BACKGROUND

Statins are the first-line therapy for reducing low-density lipoprotein cholesterol (LDL-C). However, there are secondary prevention patients who are either intolerant to maximal statin therapy or do not get adequate effects from a high-intensity statin. While data exist for the additional LDL-C-lowering effects of ezetimibe, there are no data on additional LDL-C lowering of bile acid sequestrants when combined with statin therapy. The purpose of this study was to quantify the LDL-C-lowering effects of bile acid sequestrants when added to statin therapy.

METHODS

Databases (Medline via PubMed, Embase, and the Cochrane Library) were searched for randomized controlled trials comparing statin therapy to statin therapy with the addition of bile acid sequestrants. Nine studies were included in the meta-analysis. A meta-regression was performed to estimate the mean difference in LDL-C between the 2 groups.

RESULTS

Without controlling for other variables, data suggest that combining statin with bile acid sequestrant increases the percentage change in LDL-C by 16.2 points, on average, compared with statin use alone.

CONCLUSION

In patients unable to tolerate an adequate statin dosage, bile acid sequestrants offer a viable alternative with additional LDL-C-lowering benefit.

Canadian Association of Gastroenterology Clinical Practice Guideline on the Management of Bile Acid Diarrhea

BACKGROUND & AIMS

Chronic diarrhea affects about 5% of the population overall. Altered bile acid metabolism is a common but frequently undiagnosed cause.

METHODS

We performed a systematic search of publication databases for studies of assessment and management of bile acid diarrhea (BAD). The certainty (quality) of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development and Evaluation approach. Patient population, intervention, comparator, and outcome questions were developed through an iterative process and were voted on by a group of specialists.

RESULTS

The certainty of evidence was generally rated as very low. Therefore, 16 of 17 recommendations are conditional. In patients with chronic diarrhea, consideration of risk factors (terminal ileal resection, cholecystectomy, or abdominal radiotherapy), but not additional symptoms, was recommended for identification of patients with possible BAD. The group suggested testing using ⁷⁵selenium homocholic acid taurine (where available) or 7α-hydroxy-4-cholesten-3-one, including patients with irritable bowel syndrome with diarrhea, functional diarrhea, and Crohn's disease without inflammation. Testing was suggested over empiric bile acid sequestrant therapy (BAST). Once remediable causes are managed, the group suggested cholestyramine as initial therapy, with alternate BAST when tolerability is an issue. The group suggested against BAST for patients with extensive ileal Crohn's disease or resection and suggested alternative antidiarrheal agents if BAST is not tolerated. Maintenance BAST should be given at the lowest effective dose, with a trial of intermittent, on-demand administration, concurrent medication review, and reinvestigation for patients whose symptoms persist despite BAST.

CONCLUSIONS

Based on a systematic review, BAD should be considered for patients with chronic diarrhea. For patients with positive results from tests for BAD, a trial of BAST, initially with cholestyramine, is suggested.

Canadian Association of Gastroenterology Clinical Practice Guideline on the Management of Bile Acid Diarrhea

Background and Aims

Chronic diarrhea affects about 5% of the population overall. Altered bile acid metabolism is a common but frequently undiagnosed cause.

Methods

We performed a systematic search of publication databases for studies of assessment and management of bile acid diarrhea (BAD). The certainty (quality) of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development and Evaluation approach. Patient population, intervention, comparator and outcome questions were developed through an iterative process and were voted on by a group of specialists.

Results

The certainty of evidence was generally rated as very low. Therefore, 16 of 17 recommendations are conditional. In patients with chronic diarrhea, consideration of risk factors (terminal ileal resection, cholecystectomy or abdominal radiotherapy), but not additional symptoms, was recommended for identification of patients with possible BAD. The group suggested testing using ⁷⁵selenium homocholic acid taurine (where available) or 7α-hydroxy-4-cholesten-3-one, including patients with irritable bowel syndrome with diarrhea, functional diarrhea and Crohn's disease without inflammation. Testing was suggested over empiric bile acid sequestrant therapy (BAST). Once remediable causes are managed, the group suggested cholestyramine as initial therapy, with alternate BAST when tolerability is an issue. The group suggested against BAST for patients with extensive ileal Crohn's disease or resection and suggested alternative antidiarrheal agents if BAST is not tolerated. Maintenance BAST should be given at the lowest effective dose, with a trial of intermittent, on-demand administration, concurrent medication review and reinvestigation for patients whose symptoms persist despite BAST.

Conclusions

Based on a systematic review, BAD should be considered for patients with chronic diarrhea. For patients with positive results from tests for BAD, a trial of BAST, initially with cholestyramine, is suggested.

Interventions to improve adherence to lipid-lowering medication

BACKGROUND

Lipid-lowering drugs are widely underused, despite strong evidence indicating they improve cardiovascular end points. Poor patient adherence to a medication regimen can affect the success of lipid-lowering treatment.

OBJECTIVES

To assess the effects of interventions aimed at improving adherence to lipid-lowering drugs, focusing on measures of adherence and clinical outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO and CINAHL up to 3 February 2016, and clinical trials registers (ANZCTR and ClinicalTrials.gov) up to 27 July 2016. We applied no language restrictions.

SELECTION CRITERIA

We evaluated randomised controlled trials of adherence-enhancing interventions for lipid-lowering medication in adults in an ambulatory setting with a variety of measurable outcomes, such as adherence to treatment and changes to serum lipid levels. Two teams of review authors independently selected the studies.

DATA COLLECTION AND ANALYSIS

Three review authors extracted and assessed data, following criteria outlined by the Cochrane Handbook for Systematic Reviews of Interventions. We assessed the quality of the evidence using GRADEPro.

MAIN RESULTS

For this updated review, we added 24 new studies meeting the eligibility criteria to the 11 studies from prior updates. We have therefore included 35 studies, randomising 925,171 participants. Seven studies including 11,204 individuals compared adherence rates of those in an intensification of a patient care intervention (e.g. electronic reminders, pharmacist-led interventions, healthcare professional education of patients) versus usual care over the short term (six months or less), and were pooled in a meta-analysis. Participants in the intervention group had better adherence than those receiving usual care (odds ratio (OR) 1.93, 95% confidence interval (CI) 1.29 to 2.88; 7 studies; 11,204 participants; moderate-quality evidence). A separate analysis also showed improvements in long-term adherence rates (more than six months) using intensification of care (OR 2.87, 95% CI 1.91 to 4.29; 3 studies; 663 participants; high-quality evidence). Analyses of the effect on total cholesterol and LDL-cholesterol levels also showed a positive effect of intensified interventions over both short- and long-term follow-up. Over the short term, total cholesterol decreased by a mean of 17.15 mg/dL (95% CI 1.17 to 33.14; 4 studies; 430 participants; low-quality evidence) and LDL-cholesterol decreased by a mean of 19.51 mg/dL (95% CI 8.51 to 30.51; 3 studies; 333 participants; moderate-quality evidence). Over the long term (more than six months) total cholesterol decreased by a mean of 17.57 mg/dL (95% CI 14.95 to 20.19; 2 studies; 127 participants; high-quality evidence). Included studies did not report usable data for health outcome indications, adverse effects or costs/resource use, so we could not pool these outcomes. We assessed each included study for bias using methods described in the Cochrane Handbook for Systematic Reviews of Interventions. In general, the risk of bias assessment revealed a low risk of selection bias, attrition bias, and reporting bias. There was unclear risk of bias relating to blinding for most studies.

AUTHORS' CONCLUSIONS

The evidence in our review demonstrates that intensification of patient care interventions improves short- and long-term medication adherence, as well as total cholesterol and LDL-cholesterol levels. Healthcare systems which can implement team-based intensification of patient care interventions may be successful in improving patient adherence rates to lipid-lowering medicines.

Dietary Administration of Colesevelam Hydrochloride Does Not Affect Fertility or Reproductive Performance in Rats

Colesevelam hydrochloride (HCl) (WelChol; Sankyo Pharma) is a novel, highly potent, bile acid-binding polymer used for the treatment of hypercholesterolemia. The primary aim of this study was to determine the effects of dietarily administered colesevelam HCl on fertility and reproductive performance parameters. To assess these effects, sexually mature Sprague-Dawley rats were randomized to one of five treatment groups: feed alone, feed plus control article (SigmaCell), or feed plus colesevelam HCl 200, 1000, or 2000 mg/kg/day. Male and female rats were administered the appropriate group agent for 28 and 15 days, respectively, and were subsequently paired together for cohabitation and mating. Females continued to receive the test agent in their dietary formulation through presumed gestation day (GD) 7. Presumed pregnant females underwent cesarean section on GD 20. Food consumption rate, body weight, gross necropsy, and standard preclinical tests for reproduction and fertility were performed for each test animal. No statistically significant differences were found between control and drug-treated groups for any tested endpoints of reproduction. All animals placed in cohabitation successfully mated. Uterine and litter end points were unaffected by dosages of colesevelam HCl as high as 2000 mg/kg/day. There were no significant differences between treatment group litter averages in the number of corpora lutea, implantation sites, litter size, live fetuses, body weights, early/late resorptions, and the number of dams with viable fetuses. In addition, no external alterations of fetal morphology were attributable to treatment with colesevelam HCl when administered up to the embryo implantation stage. In male animals, no significant differences were found between the colesevelam HCl and control study groups in the average caudal epididymal sperm count or sperm concentration, total number of motile and nonmotile sperm, and the total percentage of motile sperm. Based on these data, colesevelam HCl does not have any significant adverse reproductive or fertility effects in rats, even when administered at doses approximately 30 times greater than the approved clinical dose.

Over-the-counter fish oil use in a county hospital: Medication use evaluation and efficacy analysis

BACKGROUND

Little is known about the use and effectiveness of over-the-counter (OTC) fish oil supplements for triglyceride (TG) lowering.

OBJECTIVES

To (1) perform a medication-use evaluation (MUE) and (2) assess the efficacy of OTC fish oil.

METHODS

Retrospective, observational cohort study using electronic medical records and the pharmacy database from Parkland Health and Hospital System in Dallas, Texas. Parkland is a tax-supported county institution that provides patients with single-brand OTC fish oil. Two separate analyses were conducted. Six hundred seventeen patients (prescribed fish oil between July 1, 2012, and August 31, 2012) were included in the MUE analysis and 235 patients (109 fish oil, 72 fenofibrate, and 54 gemfibrozil, prescribed between January 1, 2012, and July 31, 2013) were included in the efficacy analysis. The main outcome measure for the MUE was fish oil prescribing habits including dosages and patient adherence, as defined by medication possession ratio. The main outcome measure for the efficacy analysis was change in lipids measured using the last value before fish oil treatment and the first value after fish oil treatment.

RESULTS

MUE: 617 patients received prescriptions for OTC fish oil. Sixty-four percent were prescribed a total daily dose of 2000 mg. Only 25% of patients were adherent. Efficacy analysis: despite being prescribed suboptimal doses, fish oil reduced TGs by 29% (95% confidence interval, 34.3-22.7). Compared with fish oil therapy, fibrate therapy resulted in a greater TG reduction: 48.5% (55.1-41.0) with fenofibrate and 49.8% (57.6-40.5) with gemfibrozil (P < .0001, both medications compared with fish oil).

CONCLUSIONS

Health care providers prescribe suboptimal doses of fish oil, and adherence is poor. Even at low doses (2 g/d), though, fish oil lowers TGs by 29%.

Effect of colesevelam on faecal bile acids and bowel functions in diarrhoea-predominant irritable bowel syndrome

BACKGROUND

About one-third of patients with IBS-diarrhoea (irritable bowel syndrome-D) have evidence of increased bile acid synthesis or excretion.

AIMS

To assess effects of the bile acid sequestrant, colesevelam, on faecal excretion of BAs, hepatic BA synthesis and diarrhoea in IBS-D; to appraise whether individual or random stool samples accurately reflect 48-h total faecal bile acid excretion and proportions of the main bile acids excreted and to study the faecal fat excretion in response to colesevelam.

METHODS

A single-centre, unblinded, single-dose trial of effects of colesevelam, 1875 mg [3 tablets (625 mg tablets)] orally, twice daily, for 10 days on total 48-h faecal bile acid excretion and fasting serum C4 (7α-hydroxy-4-cholesten-3-one; surrogate of hepatic bile acid synthesis). Stool diaries documented bowel functions for 8 days prior and 8 days during colesevelam treatment. Stool 48-h samples and fasting serum were collected for faecal fat, faecal bile acid and serum C4.

RESULTS

Colesevelam was associated with significantly increased faecal total bile acid excretion and deoxycholic acid excretion, increased serum C4 and more solid stool consistency. There was a significant inverse correlation between number of bowel movements per week and the total bile acid sequestered into stool during the last 48 h of treatment. Random stool samples did not accurately reflect 48-h total or individual faecal bile acid excretion. Sequestration of bile acids by colesevelam did not increase faecal fat.

CONCLUSIONS

Colesevelam increases delivery of bile acids to stool while improving stool consistency, and increases hepatic bile acid synthesis, avoiding steatorrhoea in patients with IBS-D. Overall effects are consistent with luminal bile acid sequestration by colesevelam.

Statins for the primary prevention of cardiovascular disease

BACKGROUND

Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of CVD is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with CVD. The case for primary prevention was uncertain when the last version of this review was published (2011) and in light of new data an update of this review is required.

OBJECTIVES

To assess the effects, both harms and benefits, of statins in people with no history of CVD.

SEARCH METHODS

To avoid duplication of effort, we checked reference lists of previous systematic reviews. The searches conducted in 2007 were updated in January 2012. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2022, Issue 4), MEDLINE OVID (1950 to December Week 4 2011) and EMBASE OVID (1980 to 2012 Week 1).There were no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials of statins versus placebo or usual care control with minimum treatment duration of one year and follow-up of six months, in adults with no restrictions on total, low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion and extracted data. Outcomes included all-cause mortality, fatal and non-fatal CHD, CVD and stroke events, combined endpoints (fatal and non-fatal CHD, CVD and stroke events), revascularisation, change in total and LDL cholesterol concentrations, adverse events, quality of life and costs. Odds ratios (OR) and risk ratios (RR) were calculated for dichotomous data, and for continuous data, pooled mean differences (MD) (with 95% confidence intervals (CI)) were calculated. We contacted trial authors to obtain missing data.

MAIN RESULTS

The latest search found four new trials and updated follow-up data on three trials included in the original review. Eighteen randomised control trials (19 trial arms; 56,934 participants) were included. Fourteen trials recruited patients with specific conditions (raised lipids, diabetes, hypertension, microalbuminuria). All-cause mortality was reduced by statins (OR 0.86, 95% CI 0.79 to 0.94); as was combined fatal and non-fatal CVD RR 0.75 (95% CI 0.70 to 0.81), combined fatal and non-fatal CHD events RR 0.73 (95% CI 0.67 to 0.80) and combined fatal and non-fatal stroke (RR 0.78, 95% CI 0.68 to 0.89). Reduction of revascularisation rates (RR 0.62, 95% CI 0.54 to 0.72) was also seen. Total cholesterol and LDL cholesterol were reduced in all trials but there was evidence of heterogeneity of effects. There was no evidence of any serious harm caused by statin prescription. Evidence available to date showed that primary prevention with statins is likely to be cost-effective and may improve patient quality of life. Recent findings from the Cholesterol Treatment Trialists study using individual patient data meta-analysis indicate that these benefits are similar in people at lower (< 1% per year) risk of a major cardiovascular event.

AUTHORS' CONCLUSIONS

Reductions in all-cause mortality, major vascular events and revascularisations were found with no excess of adverse events among people without evidence of CVD treated with statins.

Comparing Medication Adherence Methods in Lipid-Modifying Therapy

Background:

Investigators have employed a number of different methods to calculate adherence estimates for patients taking lipid-modifying therapy (LMT), including measures with different numerator and denominator options. Although at least one method is known to correlate well with cardiovascular outcomes, most have not been evaluated in outcomes studies.

Objectives:

To evaluate different methods for measuring adherence, using LMT as a case example, and to determine whether estimates for adherence differ statistically and/or whether different methods can lead to different conclusions about patient adherence.

Methods:

Adherence ratios were calculated using 8 different methods for 12,448 patients who were in a managed-care system and were considered new starts with statin therapy. The calculated measures were compared and tested for differences. Patients were categorized as adherent by each method, using a threshold of 0.8, and the proportions of patients categorized as adherent were compared for differences between adherence calculation methods.

Results:

Adherence ratios calculated with like observation intervals did not vary substantially, regardless of which method for measuring medication availability was used. Those calculated with different observation intervals had substantial variability. Mean adherence ratios ranged between 0.777 and 0.798 for difference in days' observation intervals; they ranged between 0.618 and 0.630 for the predefined interval. Differences between ratios calculated using these different denominators were statistically significant (p < 0.008). Correlations between ratios were statistically significant for all comparisons (p < 0.001). Correlation coefficients ( r) were 0.64 for comparisons between ratios with different denominators versus 1.0 for comparisons with like denominators. Categorization as adherent or nonadherent differed between the methods for about 20% of patients.

Conclusions:

Significant differences were found to be based on observation period but not on medication availability. Studies of adherence should be interpreted with caution depending on which method is used, and particular interest should be paid to whether the choice of methods is consistent with study objectives and to the observation interval, as different methods may lead to different conclusions about patient adherence. Further research in LMT and other therapeutic areas is needed to determine which methods correlate best with positive patient outcomes, such as reductions in low-density lipoprotein cholesterol and cardiovascular events.

Statins for the primary prevention of cardiovascular disease

BACKGROUND

Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of coronary heart disease (CHD) is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with coronary artery disease. The case for primary prevention, however, is less clear.

OBJECTIVES

To assess the effects, both harms and benefits, of statins in people with no history of CVD.

SEARCH STRATEGY

To avoid duplication of effort, we checked reference lists of previous systematic reviews. We searched the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (2001 to March 2007) and EMBASE (2003 to March 2007). There were no language restrictions.

SELECTION CRITERIA

Randomised controlled trials of statins with minimum duration of one year and follow-up of six months, in adults with no restrictions on their total low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD, were included.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion and extracted data. Outcomes included all cause mortality, fatal and non-fatal CHD, CVD and stroke events, combined endpoints (fatal and non-fatal CHD, CVD and stroke events), change in blood total cholesterol concentration, revascularisation, adverse events, quality of life and costs. Relative risk (RR) was calculated for dichotomous data, and for continuous data pooled weighted mean differences (with 95% confidence intervals) were calculated.

MAIN RESULTS

Fourteen randomised control trials (16 trial arms; 34,272 participants) were included. Eleven trials recruited patients with specific conditions (raised lipids, diabetes, hypertension, microalbuminuria). All-cause mortality was reduced by statins (RR 0.83, 95% CI 0.73 to 0.95) as was combined fatal and non-fatal CVD endpoints (RR 0.70, 95% CI 0.61 to 0.79). Benefits were also seen in the reduction of revascularisation rates (RR 0.66, 95% CI 0.53 to 0.83). Total cholesterol and LDL cholesterol were reduced in all trials but there was evidence of heterogeneity of effects. There was no clear evidence of any significant harm caused by statin prescription or of effects on patient quality of life.

AUTHORS' CONCLUSIONS

Although reductions in all-cause mortality, composite endpoints and revascularisations were found with no excess of adverse events, there was evidence of selective reporting of outcomes, failure to report adverse events and inclusion of people with cardiovascular disease. Only limited evidence showed that primary prevention with statins may be cost effective and improve patient quality of life. Caution should be taken in prescribing statins for primary prevention among people at low cardiovascular risk.

Patient, physician, and payment predictors of statin adherence

BACKGROUND

Although many patient, physician, and payment predictors of adherence have been described, knowledge of their relative strength and overall ability to explain adherence is limited.

OBJECTIVES

To measure the contributions of patient, physician, and payment predictors in explaining adherence to statins.

RESEARCH DESIGN

Retrospective cohort study using administrative data.

SUBJECTS

A total of 14,257 patients insured by Horizon Blue Cross Blue Shield of New Jersey who were newly prescribed a statin cholesterol-lowering medication.

MEASURES

Adherence to statin medication was measured during the year after the initial prescription, based on proportion of days covered. The impact of patient, physician, and payment predictors of adherence were evaluated using multivariate logistic regression. The explanatory power of these models was evaluated with C statistics, a measure of the goodness of fit.

RESULTS

Overall, 36.4% of patients were fully adherent. Older patient age, male gender, lower neighborhood percent black composition, higher median income, and fewer number of emergency department visits were significant patient predictors of adherence. Having a statin prescribed by a cardiologist, a patient's primary care physician, or a US medical graduate were significant physician predictors of adherence. Lower copayments also predicted adherence. All of our models had low explanatory power. Multivariate models including patient covariates only had greater explanatory power (C = 0.613) than models with physician variables only (C = 0.566) or copayments only (C = 0.543). A fully specified model had only slightly more explanatory power (C = 0.633) than the model with patient characteristics alone.

CONCLUSIONS

Despite relatively comprehensive claims data on patients, physicians, and out-of-pocket costs, our overall ability to explain adherence remains poor. Administrative data likely do not capture many complex mechanisms underlying adherence.

Interventions to improve adherence to lipid lowering medication

BACKGROUND

Lipid lowering drugs are still widely underused, despite compelling evidence about their effectiveness in the treatment and prevention of cardiovascular disease. Poor patient adherence to a medication regimen is a major factor in the lack of success in treating hyperlipidaemia. In this updated review we focus on interventions which encourage patients at risk of heart disease or stroke to take lipid lowering medication regularly.

OBJECTIVES

To assess the effects of interventions aimed at improved adherence to lipid lowering drugs, focusing on measures of adherence and clinical outcomes.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1), MEDLINE, EMBASE, PsycINFO and CINAHL (March 2008). No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials of adherence-enhancing interventions for lipid lowering medication in adults for both primary and secondary prevention of cardiovascular disease in an ambulatory setting looking at adherence, serum lipid levels, adverse effects and health outcomes. Studies were selected independently by two review authors.

DATA COLLECTION AND ANALYSIS

Data were extracted and assessed by two review authors following criteria outlined by the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Three additional studies were found in the update and, in total, 11 studies were included in this review. The studies included interventions that caused a change in adherence ranging from -3% to 25% (decrease in adherence by 3% to increase in adherence by 25%). Patient re-enforcement and reminding was the most promising category of interventions, investigated in six trials of which four showed improved adherent behaviour of statistical significance (absolute increase: 24%, 9%, 8% and 6%). Other interventions associated with increased adherence were simplification of the drug regimen (absolute increase 11%) and patient information and education (absolute increase 13%). The methodological and analytical quality of some studies was low and results have to be considered with caution.

AUTHORS' CONCLUSIONS

At this stage, reminding patients seems the most promising intervention to increase adherence to lipid lowering drugs. The lack of a gold standard method of measuring adherence is one major barrier in adherence research. More reliable data might be achieved by newer methods of measurement, more consistency in adherence assessment and longer duration of follow up. More recent studies have started using more reliable methods for data collection but follow-up periods remain too short. Increased patient-centredness with emphasis on the patient's perspective and shared decision-making might lead to more conclusive answers when searching for tools to encourage patients to take lipid lowering medication.

The contribution of ApoB and ApoA1 measurements to cardiovascular risk assessment

LDL has been widely recognized as the major atherogenic lipoprotein and designated as the primary target for prevention of coronary heart disease (CHD); however, there is growing evidence that other triglyceride-rich lipoproteins, such as very low-density lipoprotein (VLDL) and intermediate density lipoprotein (IDL) carry atherogenic potential as well. This led to the designation of non-HDL cholesterol (HDL-C) (LDL + IDL + VLDL) as a secondary target of treatment for hyperlipidaemia. As each one of LDL, IDL and VLDL particles carries only one apolipoprotein B-100 (ApoB-100) molecule, the total ApoB value represents the total number of potentially atherogenic lipoproteins, whereas non-HDL-C provides the cholesterol content of these same lipoproteins. Recent data from epidemiological, observational and interventional studies suggest that non-HDL-C, apolipoproteins ApoA1 and ApoB may improve CHD risk assessment by identifying more high-risk individuals than the usual lipid profile alone. However, the targets for the optimal treatment of dyslipidaemia remain a subject of considerable debate. Further studies are needed to determine whether ApoB and ApoA1 are superior to conventional lipid parameters as predictors of cardiovascular disease or therapeutic targets of hyperlipidaemias. In this review, we summarize the current opinions on the use of ApoA1 and ApoB values as estimates of cardiovascular risk or as treatment goals in patients undergoing treatment for hyperlipidaemia.

Evaluation of the prescription and utilization patterns of statins in an Italian local health unit during the period 1994-2003

OBJECTIVES

The prescription pattern of statins in the Local Health Unit (LHU) of Treviso (northern Italy) over a 10-year period was evaluated, with the aim of evaluating the persistence with and adherence to therapy.

METHODS

Data on 21,393 subjects who received at least one prescription for statins during the period between January 1, 1994 and December 31, 2003 were retrieved from the LHU database in order to track the pharmacological history of individual patients. The data included age, sex, drug formulation, strength, number of drug packages prescribed, and prescription date. The adopted indicators for drug utilization included the Defined Daily Dose (DDD), the Received Daily Dose (RDD), and a surrogated Prescribed Daily Dose (sPDD), extrapolated from available prescription data. An Adherence to Therapy Index (ATI) was calculated from the ratio between the amount of drug actually prescribed and the amount of sPDD. Based on the ATI, patients were grouped into non-adherent, poor-adherent, and good-adherent groups. The distribution of adherence level among patient-age classes and statin-prescribed patients in primary or secondary prevention was evaluated.

RESULTS

All drug-utilization indicators showed an increase in statin use over the study period in terms of both the number of prescribed patients and the sPDD. Persistence with and adherence to therapy remained low, with a 50% discontinuation rate in the first year, and persistent patients did not follow the therapy regularly. Patients in secondary prevention were the most adherent to their drug regimen, although only 41% of these had a good compliance.

CONCLUSIONS

Our findings suggest an increase in statin use which is, however, accompanied by poor patient persistence with and adherence to statin therapy.

The exclusion of patients with chronic kidney disease from clinical trials in coronary artery disease

Chronic kidney disease (CKD) is associated with a high risk of death from coronary artery disease and may modify the response to standard cardiovascular therapies. Treatment of subjects with CKD should ideally be based on evidence from randomized, clinical trials, but how often subjects with CKD have been excluded from these trials is uncertain. We undertook this study in order to quantify how often subjects with moderate to advanced CKD were excluded from large cardiovascular trials. MEDLINE and the reference list of selected articles were searched in order to identify large, randomized, controlled trials of five different coronary artery disease therapies published between 1998 and 2005. Exclusion criteria and reported clinical characteristics of subjects were abstracted. Rates of exclusion and reporting of baseline characteristics of study participants were compared for CKD, diabetes, history of smoking, and hypertension. Eighty-six trials randomizing 411 653 patients were identified. More than 80% of trials excluded subjects with end-stage renal disease and 75.0% excluded patients with CKD. Subjects with diabetes, hypertension, or a history of smoking were excluded less than 4% of the time. Baseline renal function of study participant was reported in only 7% of trials. Patients with CKD are frequently excluded from coronary artery disease trials and renal function of randomized subjects is rarely reported. These findings reinforce the notion that available data on the treatment of coronary artery disease in subjects with CKD have significant limitations and should be generalized to the treatment of subjects with CKD cautiously.

Colesevelam: Potential Uses for the Newest Bile Resin

Colesevelam is the newest bile resin with a unique chemical structure. It binds to bile acids with higher affinity than traditional bile acid sequestrants and has fewer gastrointestinal side effects and drug interactions. Colesevelam is safe and efficacious alone or in combination with HMG-CoA reductase inhibitors (statins) in reducing low-density lipoprotein cholesterol (LDL-C) levels. Despite this, the role of colesevelam in the treatment of hyperlipidemia remains limited, particularly in the face of new lipid lowering agents. As guidelines for cholesterol control become more stringent, the need to maximize therapeutic benefit through combination therapy will become increasingly more important. Colesevelam has a dose-sparing effect on statin therapy, potentially decreasing the risk of unwanted side effects or drug-drug interactions associated with statin use. This makes colesevelam a viable option for addition to a statin regimen when goal LDL-C levels cannot be achieved with a statin alone. Additionally, anecdotal reports indicate that colesevelam may have potential benefits in certain patient populations that cannot tolerate other lipid lowering therapies, including organ transplant recipients, cholestatic liver disesase, and end-stage renal disease. By recognizing the potential utility of colesevelam, clinicians can better manage those patients who are not able to tolerate first-line therapies.

Managing abnormal blood lipids: a collaborative approach

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

Persistence and determinants of statin therapy among middle-aged patients free of cardiovascular disease

AIM

Statins have been shown to significantly reduce morbidity and mortality both in patients with coronary artery disease and in those with dyslipidemia when they are taken regularly. Middle-aged patients have the highest level of forecasting benefit, and little is known about the persistence rate of these therapies in a real-life setting.Objective. To evaluate the persistence rate of middle-aged patients initiating statin therapy as well as its relation to patients' demographic and clinical characteristics.

METHODS

A cohort of 25,733 patients was reconstructed from prescription data recorded in the Régie de l'assurance maladie du Québec administrative database. All patients aged 50-64 years old who received at least one statin prescription between January 1, 1998 and December 31, 2000 for a new intention of treatment for dyslipidemia were included in the cohort and followed up until June 30, 2001. The date of the first prescription of statin was defined as the index date. The cumulative persistence rate was estimated using a Kaplan-Meier analysis. Cox regression models were used to estimate the rate ratio of ceasing statins after adjustment.

RESULTS

Mean age of patients initiating statin agents was 58 years; 39%were male, 24% received social assistance, 19% had diabetes, 30% had hypertension and 11% had a respiratory disease at cohort entry. Persistence with statin therapy fell to 67% in the first 6 months after treatment and continued to decline over the next 3 years to 39%. At 3 years, persistence varied significantly with statin agents. After controlling for individual patients' demographic and clinical characteristics, we found that patients who were prescribed fluvastatin, lovastatin and atorvastatin had a higher rate of cessation than those on simvastatin and pravastatin. The adjusted rate ratio of ceasing statin agents in patients with other risk factors of cardiovascular disease, such as diabetes (HR: 0.78; 0.75-0.82) or hypertension (HR: 0.72; 0.69-0.74), demonstrated a lower cessation rate. We observed lower persistence in patients who used the greatest number of pharmacies and prescribing physicians.

CONCLUSION

This analysis indicates that barriers to persistence occur early in the therapeutic course. Overall persistence with statins is low, particularly among patients with few other cardiovascular risk factors.

Persistence and determinants of statin therapy among middle-aged patients for primary and secondary prevention

AIMS

Statins have been shown to significantly reduce morbidity and mortality in patients with coronary artery disease (CAD), and also in patients with dyslipidaemia when statins are taken regularly. Middle-aged patients have the highest level of forecasting benefit and little is known about persistence rate of these therapies in a real-life setting. The objective was to evaluate the persistence rate of middle-aged patients initiating a statin therapy and its relation with several determinants for primary and secondary prevention.

METHODS

A cohort was reconstructed using the RAMQ databases. All patients aged 50-64 years-old who received at least one statin prescription between 1 January, 1998 and 31 December, 2000 for a new intention of treatment for dyslipidaemia were included in the cohort and followed up until 30 June, 2001. The date of the first prescription of statin was defined as the index date. There were 4316 patients in the secondary prevention (CAD diagnosis) and 13,642 patients in primary prevention cohort. The cumulative persistence rate was estimated using Kaplan-Meier, and Cox regression models were used to estimate the hazard ratio of ceasing statins.

RESULTS

We found that persistence with statins had fallen to 71% after 6 months of treatment, and had declined to 45% after 3 years in the secondary prevention cohort; the corresponding figures were 65% and 35% in the primary prevention cohort. Our results suggest that patients with dyslipidaemia in primary prevention compared with those in secondary prevention (HR: 1.18; 1.11-1.25) are less likely to be persistent. Patients with other cardiovascular risk factors such as age (HR: 0.99; 0.98-0.99), diabetes (HR: 0.84; 0.79-0.90), hypertension (HR: 0.76; 0.72-0.80) were most likely to be persistent with statins. We observed lower persistence in patients who have used the greatest number of pharmacies and prescribing physicians.

CONCLUSION

This analysis indicates that barriers to persistence occur early in the therapeutic course. Overall persistence with statins is low, and particularly among patients with few other cardiovascular risk factors.

Efficacy of Colestimide Coadministered With Atorvastatin in Japanese Patients With Heterozygous Familial Hypercholesterolemia (FH)

BACKGROUND

Colestimide, a 2-methylimidazole-epichlorohydrin polymer, is a new bile-acid-sequestering resin, that is 4-fold as powerful at lowering low-density lipoprotein cholesterol (LDL-C) as the conventional resin (cholestyramine). Moreover, colestimide has excellent patient compliance because it is available in tablet form.

METHODS AND RESULTS

The clinical efficacy of colestimide coadministered with atorvastatin on lipid and apolipoprotein concentrations was examined in 15 patients (M/F=10/5, mean+/-SE age=54+/-9 years) with heterozygous familial hypercholesterolemia (FH). After a period of wash-out of any lipid-lowering drugs, atorvastatin (20-40 mg) was administered to patients for at least 8 weeks, and then 3 g of colestimide was administered for a further 8 weeks. Total and LDL-C significantly (<0.0001) decreased by 35% from 361 to 233 mg/dl and 41% from 274 to 161 mg/dl, respectively. Addition of colestimide caused a further significant 12% and 20% reduction, respectively, from the initial values to 205 and 129 mg/dl, respectively. Colestimide was also effective in reducing serum LDL-C concentrations in heterozygous FH patients with hypertriglyceridemia (triglycerides>or=150 mg/dl).

CONCLUSIONS

When monotherapy with atorvastatin is insufficient to treat severely hypercholesterolemic patients, such as those with heterozygous FH, colestimide acts to reinforce the action of statins.

Economic evaluation of a compliance-enhancing intervention in patients with hypercholesterolemia: design and baseline results of the Open Label Primary Care Study: Rosuvastatin Based Compliance Initiatives To Achievements of LDL Goals (ORBITAL) study

BACKGROUND

Previous studies investigating the effectiveness of compliance programs in patients with cardiovascular risk factors have been inconclusive and have not included economic analyses. The primary aim of this Open Label Primary Care Study: Rosuvastatin Based Compliance Initiatives To Achievements of LDL Goals (ORBITAL) study is to determine the long-term cost-effectiveness of a compliance-enhancing intervention in patients with hypercholesterolemia (HC). Secondary objectives include the assessment of compliance, cardiovascular events, and health-related quality of life.

STUDY DESIGN

A total of 7598 patients (56% men, age 60 +/- 10 years, and 44% women, 64 +/- 10 years) with HC requiring statin therapy according to the Second Joint European Guidelines were recruited at presentation to 1961 primary care physicians in Germany. Patients were randomized to rosuvastatin therapy with or without a compliance-enhancing program (including standardized contacts between the study center and patients, 9 mailings, 6 telephone calls, and access to a Web page and hotline) for 12 months. Following the intervention phase, there will be a 24-month observational period with patients receiving usual care. Baseline and 6-monthly follow-up assessments are to be obtained from patients and their physicians using standardized questionnaires to evaluate medical and economic parameters. Cumulative direct and indirect disease-related costs (including resource utilization for ambulatory, hospital, rehabilitative, and nursing care, medication, physiotherapy, and transportation, and loss of productivity) will be compared applying a societal perspective.

CONCLUSIONS

The results of this ORBITAL study will provide a basis to develop cost-effective compliance strategies and eventually improve medical care for patients with HC.

Association between adherence to statin therapy and lipid control in Hong Kong Chinese patients at high risk of coronary heart disease

AIMS

To examine the pattern of adherence to statin therapy and to determine the association of adherence to statin therapy and the control of serum low-density lipoprotein (LDL)-cholesterol in a cohort of Hong Kong Chinese patients at high risk of coronary heart disease (CHD).

METHODS

This was a prospective observational cohort study conducted at the outpatient clinics of a public teaching hospital in Hong Kong. Patients at high risk of CHD who had been initiated on statin monotherapy for < 12 months were recruited. The statin prescription was dispensed in a bottle with the Medication Event Monitoring System (MEMS). Adherence was assessed in two dimensions: dose-count was defined as the percentage of doses taken, and dose-time was defined as the percentage of doses taken within the suggested time interval. Lipid profiles were obtained at baseline and during two follow-up visits at month 3 and month 6.

RESULTS

Eighty-three patients completed the study. The median adherence to dose-count and to dose-time were 95% (25-75th percentile = 87-99%) and 78% (25-75th percentile = 17-92%), respectively. Both dose-count and dose-time adherence declined slightly over the first 6 months of therapy. Living with family [relative risk (RR) = 0.79, 95% confidence interval (CI) 0.63, 0.91] and duration of therapy (RR = 0.99, 95% CI 0.98, 1.00) were negative predictors while number of family members (among those living with family) (RR = 1.05, 95% CI 1.00, 1.08) was a positive predictor for adherence to dose-count. Monthly household income (RR = 1.01, 95% CI 1.00, 1.02) and angina (RR = 1.29, 95% CI 1.05, 1.58) were positive predictors while living with family (RR = 0.74, 95% CI 0.55, 0.90) was a negative predictor for dose-time adherence. Percent reduction in serum LDL-cholesterol was correlated to dose-count (P < 0.001) and dose-time (P = 0.047) adherence. Statistically significant correlations were observed between adherence to dose-count and LDL reduction (R(2) = 0.130; P = 0.001), and between dose-time adherence and LDL reduction (R(2) = 0.048; P = 0.047).

CONCLUSION

High adherence to statin therapy was found in a cohort of Chinese patients at high risk of CHD and the adherence declined slightly over time. A weak association between adherence to statin dose-count and LDL reduction and a marginal association between dose-time adherence and LDL reduction were observed.

Efficacy and safety of rosuvastatin alone and in combination with cholestyramine in patients with severe hypercholesterolemia: A randomized, open-label, multicenter trial

BACKGROUND

Patients with severe hypercholesterolemia may need greater cholesterol reductions than can be achieved with statin therapy alone.

OBJECTIVE

The primary objective of this trial was to compare the efficacy of a combination of rosuvastatin plus cholestyramine with that of rosuvastatin alone for reducing low-density lipoprotein cholesterol (LDL-C) levels after 6 weeks of treatment.

METHODS

In this open-label, multicenter, randomized, parallel-group, comparator trial, adult patients with severe hypercholesterolemia (LDL-C level, 190-400 mg/dL) received rosuvastatin 40 mg/d for 6 weeks after a 6-week dietary lead-in period and were then randomized to 6 weeks of treatment with rosuvastatin 80 mg/d alone or rosuvastatin 80 mg/d plus cholestyramine 16 g/d (8 g BID with meals).

RESULTS

Of 153 eligible patients, 147 (83 men, 64 women; mean [SD] age, 54.5 [13.7] years; mean [SD] bodyweight, 81.3 [14.4] kg) received randomized treatment, and 144 had post baseline measurements and were included in the analysis. The mean (SD) reduction in LDL-C was 522% (13.0%) after treatment with rosuvastatin 40 mg, and the least squares mean (SE) reductions in LDL-C were 56.4% (1.8%) and 60.5% (1.8%) after treatment with rosuvastatin 80 mg alone (n = 69) and rosuvastatin 80 mg plus cholestyramine (n = 75), respectively. No significant differences between treatments were found for these or other lipid measurements. Incremental LDL-C reductions >30% were obtained in 29% (22/75) of patients receiving combination therapy and 4% (3/69) of patients receiving rosuvastatin alone. The combination therapy was less well tolerated, primarily due to gastrointestinal symptoms; otherwise, the treatments were generally well tolerated.

CONCLUSION

In this group of patients with severe hypercholesterolemia, the combination of rosuvastatin 80 mg with cholestyramine 16 g/d did not provide a significantly greater efficacy benefit than rosuvastatin alone.

Self-Reported Adherence to Cholesterol-Lowering Medication in Patients with Familial Hypercholesterolaemia: The Role of Illness Perceptions

BACKGROUND

The objectives of this study are to describe levels of adherence to cholesterol-lowering medication and to identify predictors of adherence in patients with familial hypercholesterolaemia (FH).

DESIGN

Descriptive questionnaire study.

METHODS

336 adults patients with FH attending one of five outpatient lipid clinics in South East England underwent a clinical assessment by a nurse and completed a questionnaire. The questionnaire assessed self-reported adherence to cholesterol-lowering medication, anxiety, depression, and patient perceptions of heart disease.

RESULTS

Overall, participants reported high levels of medication adherence, although 63% reported some level of non-adherence. Total medication adherence (never deviating from the regimen) was more likely to be reported by older participants, those with no formal educational qualifications, those with a personal history of cardiovascular disease, those with a lower total cholesterol level, and those with a greater difference between untreated cholesterol levels and current cholesterol levels. The illness perceptions associated with reported total adherence were lower perceived risk of raised cholesterol, perceiving greater control over FH, and perceiving genes and cholesterol to be important determinants of a heart attack. Emotional state was not associated with medication adherence. In logistic regression analysis, predictors of total medication adherence were having personal history of cardiovascular disease, having no formal qualifications, and perceiving genes to be important determinants of a heart attack.

CONCLUSIONS

Both clinical factors and patients' illness perceptions were associated with self-reported cholesterol-lowering medication adherence. The association with illness perceptions was small and many of these associations may be a consequence, rather than a cause, of greater adherence. Given this, intervention strategies aimed at helping patients' to establish routines for medication taking may be more effective in increasing adherence than interventions designed to alter perceptions related to taking statins.

Interventions to improve adherence to lipid lowering medication

BACKGROUND

Lipid lowering drugs are still widely underused, despite compelling evidence about their effectiveness in the treatment and prevention of cardiovascular disease. Poor patient adherence to medication regimen is a major factor in the lack of success in treating hyperlipidaemia. In this review we focus on interventions, which encourage patients at risk of heart disease or stroke to take lipid lowering medication regularly.

OBJECTIVES

To assess the effect of interventions aiming at improved adherence to lipid lowering drugs, focusing on measures of adherence and clinical outcomes.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycInfo and CINAHL. Date of most recent search was in February 2003. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials of adherence-enhancing interventions to lipid lowering medication in adults for both primary and secondary prevention of cardiovascular disease in an ambulatory setting.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data independently and assessed studies according to criteria outlined by the Cochrane Reviewers' Handbook.

MAIN RESULTS

The eight studies found contained data on 5943 patients. Interventions could be stratified into four categories : 1. simplification of drug regimen, 2. patient information/education, 3. intensified patient care such as reminding and 4. complex behavioural interventions such as group sessions. Change in adherence ranged from -3% to 25% (decrease in adherence by 3% to increase in adherence by 25%). Three studies reported significantly improved adherence through simplification of drug regimen (category 1), improved patient information/education (category 2) and reminding (category 3). The fact that the successful interventions were evenly spread across the categories, does not suggest any advantage of one particular type of intervention. The methodological and analytical quality was generally low and results have to be considered with caution. Combining data was not appropriate due to the substantial heterogeneity between included randomised controlled trials (RCTs).

REVIEWERS' CONCLUSIONS

At this stage, no specific intervention aimed at improving adherence to lipid lowering drugs can be recommended. The lack of a gold standard method of measuring adherence is one major barrier in adherence research. More reliable data might be achieved by newer methods of measurement, more consistency in adherence assessment and longer duration of follow-up. Increased patient-centredness with emphasis on the patient's perspective and shared-decision-making might lead to more conclusive answers when searching for tools to encourage patients to take lipid lowering medication.

Apolipoprotein B and apolipoprotein A-I: risk indicators of coronary heart disease and targets for lipid-modifying therapy

Although LDL cholesterol (LDL-C) is associated with an increased risk of coronary heart disease, other lipoproteins and their constituents, apolipoproteins, may play an important role in atherosclerosis. Elevated levels of apolipoprotein (apo) B, a constituent of atherogenic lipoproteins, and reduced levels of apo A-I, a component of anti-atherogenic HDL, are associated with increased cardiac events. Apo B, apo A-I and the apo B/apo A-I ratio have been reported as better predictors of cardiovascular events than LDL-C and they even retain their predictive power in patients receiving lipid-modifying therapy. Measurement of these apolipoproteins could improve cardiovascular risk prediction.

Pharmacology and therapeutics of ezetimibe (SCH 58235), a cholesterol-absorption inhibitor

BACKGROUND

Ezetimibe is the first of a new class of antihyperlipidemic agents, the cholesterol-absorption inhibitors. It is indicated for monotherapy or in combination with 3-hydroxy-3-methylglutaryl coenzyme A-reductase inhibitors (statins) in patients with primary hypercholesterolemia, in combination with simvastatin or atorvastatin in patients with homozygous familial hypercholesterolemia, and as monotherapy in patients with homozygous familial sitosterolemia.

OBJECTIVE

This article reviews available data on the clinical pharmacology, clinical efficacy, and tolerability of ezetimibe.

METHODS

A literature review was conducted using the search terms ezetimibe and SCH 58235 to identify articles and abstracts indexed in MEDLINE and the Iowa Drug Information Service from 1966 to February 2003. The reference lists of the identified articles were reviewed for additional publications.

RESULTS

In adults, ezetimibe 10 mg PO given once daily has been reported to reduce intestinal cholesterol absorption by 54% from baseline in association with a compensatory increase in endogenous cholesterol synthesis. Within 2 weeks of its initiation, ezetimibe monotherapy produced a 17% to 20% reduction from baseline in low-density lipoprotein cholesterol (LDL-C); in combination with statins, ezetimibe produced a reduction in LDL-C of up to 40% over the same period. Based on studies performed to date, ezetimibe appears to be well tolerated, with a safety profile similar to that of placebo. Because ezetimibe is eliminated primarily by glucuronidation and not by cytochrome P450 (CYP) oxidation, it is subject to minimal drug interactions involving the CYP enzyme system.

CONCLUSIONS

Ezetimibe is an option for monotherapy in patients with mild hypercholesterolemia or in those requiring adjunctive drug therapy for reduction of LDL-C levels. It may be useful in patients at risk for adverse events (eg, liver toxicity, myopathy) from other hypocholesterolemic agents. Additive LDL-C-lowering effects of ezetimibe may allow use of lower doses of conventional agents (eg, statins, fibric acid derivatives, niacin) to achieve an equivalent effect, thereby reducing the potential for adverse events and drug interactions. However, because trials have lasted no longer than 12 weeks, the long-term effect of ezetimibe on cardiovascular morbidity and mortality remains to be determined.

Meta-analysis of interventions to improve drug adherence in patients with hyperlipidemia

OBJECTIVE

To examine the results of meta-analyses addressing the net effect of tools and methods to enhance drug adherence in patients with hyperlipidemia.

METHODS

We searched MEDLINE, International Pharmaceutical Abstracts (IPA), PsychLit, Educational Resource Information Clearinghouse (ERIC), and Excerpta Medica Database (EMBASE) databases (1996-2000) for randomized controlled trials of interventions to improve patients' adherence to drug regimens for hyperlipidemia. All trials selected had at least 10 subjects/group. Effect sizes, represented as the correlation coefficient, were calculated from Cohen's d and d'. Analysis of variance and the Q test were performed to evaluate statistical significance and heterogeneity.

RESULTS

Of the 484 articles evaluated, only four met the criteria for inclusion. Multiple interventions or study samples were identified in two articles. Each intervention was counted as a separate study, yielding seven cohorts with a total of 3077 subjects. Behavioral interventions accounted for five cohorts (2915 subjects). No cohorts received solely educational interventions. Two cohorts, with a total of 162 subjects, received a combination of behavioral and educational interventions. Homogeneity of groupings and effect sizes were calculated for the overall grouping as well as for each type of intervention. Overall, the effect size for the data was 0.14 (95% confidence interval [CI] 0.10-0.17) and the data were homogenous (Q = 7.36, df = 4, p = 0.29). The effect size for the behavioral interventions was 0.14 (95% CI 0.11-0.18, Q = 5.25, df = 4, p = 0.26). For interventions that combined behavioral and educational components, the effect size was 0.03 (CI -0.13-0.18, Q = 0.204, df = 1, p = 0.65).

CONCLUSIONS

The interventions evaluated had little impact on drug adherence. More studies are needed to assess how to improve drug adherence in patients with hyperlipidemia.

Management of dyslipidemia in the high-risk patient

Lipid-lowering agents have been shown to reduce morbidity and mortality associated with coronary heart disease (CHD), particularly in high-risk patients. The identification and treatment of these patients should therefore be a high priority for clinicians. Guidelines from medical organizations, such as the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP) and the American Diabetes Association (ADA), suggest that patients with low-density lipoprotein cholesterol (LDL-C) levels > or =130 mg/dL, and perhaps even those with levels > or =100 mg/dL, should receive drug therapy. Optimal LDL-C levels have been set at <100 mg/dL and <115 mg/dL for high-risk patients by US and European guidelines, respectively. However, a recent survey shows that only about 20% of high-risk patients currently meet these goals. In order to achieve therapeutic targets for LDL-C, the statins are the foundation of treatment, as they are the most effective and best-tolerated form of lipid-lowering therapy. Other therapeutic options include bile acid sequestrants, niacin, and plant stanols, although seldom as monotherapy. Combination therapy with a statin and one of these other lipid-lowering agents can be useful in patients who are unable to achieve target lipid levels through monotherapy. There remains, however, a need for additional agents. Some of the new options for reducing LDL-C levels that may be available in the near future include 2 new statins, pitavastatin and rosuvastatin. In patients with heterozygous familial hypercholesterolemia, rosuvastatin, which is currently under review by the Food and Drug Administration (FDA), has been shown to produce significantly greater reductions in LDL-C than atorvastatin over its full dose range. In comparative clinical trials, it has also enabled more patients with primary hypercholesterolemia to meet lipid goals than atorvastatin, simvastatin, and pravastatin. Inhibitors of bile acid transport or cholesterol absorption may also have therapeutic value. The first cholesterol absorption inhibitor, ezetimibe, which has just been approved by the FDA, appears to be most effective when combined with a statin. It is anticipated that such new options will allow clinicians to optimize the management of dyslipidemia in high-risk patients, thereby reducing the morbidity and mortality of CHD.

Risk factors for coronary heart disease in 55- and 35-year-old men and women in Sweden and Estonia

OBJECTIVE

To illustrate the geographical West-to-East division of coronary heart disease (CHD) by comparing a population from Sweden, that represents a Western country to a population from Estonia, that represents an Eastern country. Estonia has an approximately 2-4-fold higher CHD prevalence for 55-year-old women and men, respectively, than Sweden.

DESIGN

Randomized screening of 35- and 55-year-old men and women in Sollentuna county, Sweden and Tartu county, Estonia. Eight hundred subjects, 100 from each cohort, were invited to participate in the study, 272 Swedes and 277 Estonians participated.

SETTING

Preventive cardiology, administered by a primary health care centre at the Karolinska Hospital, Sweden and a cardiology centre at Tartu University Hospital, Estonia.

MAIN OUTCOME MEASURES

The CHD risk factors (smoking, blood pressure, concentrations of lipoproteins, fibrinogen, and glucose) and certain environmental factors and attitudes related to CHD risk by questionnaires (fat-type and alcohol ingestion, self-assessed rating of CHD susceptibility).

RESULTS

Of the 55-year-old men, 57% smoked in Estonia and 20% smoked in Sweden. Similar, although less pronounced differences showing higher smoking prevalence, were seen for 35-year-old Estonian men and women, whilst for 55-year-old women, less than 20% smoked in either country. Estonian 55-year-old women had lower HDL cholesterol and higher LDL cholesterol serum concentrations than Swedish 55-year-old women. Estonians reportedly ate food containing more saturated fats than Swedes, as indicated by the scale-score questionnaire. Estonians, relative to Swedes, rated their chance of developing CHD higher, and paradoxically, Estonians did to a much lesser degree believe that life style influences the risk of developing CHD.

CONCLUSIONS

Elevated smoking prevalence is a striking difference between the Estonian and Swedish populations likely to explain the much higher CHD prevalence in Estonian men. The lower HDL cholesterol and higher LDL cholesterol in Estonian 55-year-old women may explain the higher CHD prevalence in Estonian women. Furthermore, the SWESTONIA CHD study (i.e. comparison between Sweden and Estonia) shows several environmental differences between the countries populations related to fat content in food, alcohol drinking patterns, and views on CHD risk and the importance of lifestyle intervention, that could contribute to the higher CHD prevalence in Estonia.

Determinants of non-compliance with lipid-lowering therapy in hyperlipidemic patients

PURPOSE

In order to assess the determinants of non-compliance with a lipid-lowering therapy, a prospective study of the hyperlipidemic Korean subjects was carried out.

METHODS

A total of 1019 patients was observed by 46 family physicians for the period of 1 year from January 1999 to January 2000. To ascertain the compliance associated with a lipid lowering drug (Simvastatin), we regularly followed up the hyperlipidemic patients at intervals of 4, 12 and 24 weeks. The criterion for evaluating compliance is to measure clinic attendance. Using a structured questionnaire, patients and physicians were asked about risk factors for the compliance.

RESULTS

During the first 24 weeks of treatment, the lipid-lowering medication was continued by 52.3% and discontinued by 19.7%. The remaining 28% dropped out. Patient-related factors for non-compliance were young age, current smoker, lack of low fat diet and exercise, new user, no concomitant medication, and occurrence of adverse reactions. Physician-related factors for non-compliance were low patients' satisfaction with the physician, small number of hyperlipidemic patients per month and working in a relatively small hospital.

CONCLUSIONS

Compliance with the lipid-lowering therapy was relatively low and several factors for non-compliance were detected.

High persistence of statin use in a Danish population: compliance study 1993-1998

AIMS

Several studies have found that compliance with lipid-lowering drug (LLD) treatment is low. However, the results of these studies were based on crude measures of compliance. The aim of this study was to describe compliance with statin treatment by analysing prescription patterns on an individual level in a population-based prescription database over a 6 year period.

METHODS

For incident statin users, all prescriptions for statins and drugs indicating cardiovascular disease or diabetes were retrieved from the OPED prescription database covering a population of about 470,000 inhabitants. Treatment was considered discontinued if the interval between two prescriptions exceeded number of tablets prescribed, plus 30 days. Compliance was assessed in terms of persistence and continuity. Persistence was defined as the period from the first prescription date to the date of discontinuation. Continuity was defined as the number of days with treatment (=number of tablets) divided by the total number of days in the period of persistence.

RESULTS

11% of the study cohort only received a single statin prescription. Survival analyses revealed a median persistence of 41 months. Less than 15% of the patients had more than 20% days without therapy within the period of persistence. Patients under 45 years without drug indicators of cardiovascular disease or diabetes presented the lowest compliance.

CONCLUSIONS

The study showed good compliance with statin treatment in terms of persistence and continuity. A high percentage of the youngest patients, however, seemed to discontinue treatment before obtaining the full benefit in terms of decreased risk of coronary heart morbidity and mortality.

Managing dyslipidemia in the high-risk patient

Lipid-lowering agents have been shown to reduce morbidity and mortality associated with coronary artery disease (CAD) in all patients. However, these agents are more cost-effective in high-risk patients whose absolute risk of CAD is greater than that of low-risk patients. Furthermore, from preliminary data, it appears that there is greater risk reduction in those subjects achieving lower low-density lipoprotein cholesterol (LDL-C) levels (ie, lower is better). The identification and aggressive treatment of these patients should therefore be a high priority for clinicians. Guidelines from medical organizations, such as the Adult Treatment Panel (ATP) III of the US National Cholesterol Education Program (NCEP), emphasize that patients with CAD, diabetes, or global risk of CAD >20% over 10 years and LDL-C levels >130 mg/dL should receive drug therapy with a goal of reducing LDL-C levels to <100 mg/dL. The recent results of the United Kingdom's Heart Protection Study (HPS) strongly suggest that even those with CAD or who are at high risk and LDL-C levels >100 mg/dL would benefit from drug therapy. Although optimal LDL-C levels have been set at <100 mg/dL for high-risk patients, recent studies show only about 20% of such patients meet these goals. Thus, a large treatment gap remains that needs to be overcome if we are to continue to make significant inroads into preventing further morbidity and mortality in these high-risk subjects. Of therapeutic options available currently and for the near future, statins remain the most effective and well-tolerated form of lipid-lowering therapy. Other therapies include bile acid sequestrants, niacin, and plant stanols. However, none of these is, in general, sufficiently effective as an initial agent to achieve these more aggressive LDL-C goals in the high-risk patient. However, combination therapy with a statin and 1 of these other lipid-lowering agents is useful in patients who are unable to achieve lipid goals on monotherapy. A number of agents for reducing LDL-C levels currently in development may be available in the near future, including 2 new statins: pitavastatin and rosuvastatin. Rosuvastatin, which is in the later stages of the US Food and Drug Administration (FDA) approval process, has been shown to produce significantly greater reductions in LDL-C levels compared with atorvastatin, simvastatin, and pravastatin, and allows more patients to meet lipid goals. Ezetimibe, the first of an entirely new class of LDL-C-lowering agents that inhibit intestinal cholesterol absorption, also appears to offer significant therapeutic value. It is anticipated that these new options will allow clinicians to optimize the management of dyslipidemia in high-risk patients, thereby further reducing the morbidity and mortality of CAD.

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.

Clinical context: current concepts of coronary heart disease management

Coronary heart disease (CHD) is the single greatest cause of death among adults in the United States. It is also a major cause of disability and is associated with direct and indirect costs that exceed $118 billion annually. Elevation of serum lipid levels, particularly low-density lipoprotein cholesterol (LDL-C) levels, is closely linked to the development of CHD. Lipid levels that increase the risk of CHD are present in nearly one third of the US population. Large-scale intervention studies have shown that decreasing LDL-C can significantly reduce the risk of cardiovascular mortality, adverse cardiovascular events, and the requirement for revascularization procedures. Statins are now thought the most effective agents for lowering LDL-C, and they also have positive effects on other components of the serum lipid profile. These drugs are also better tolerated than other lipid-lowering agents. Statin therapy significantly decreases the risk of cardiovascular disease and is a cost-effective cardiovascular treatment according to current standards. Because statins vary substantially in acquisition cost, using statins in the most cost-effective manner is important for controlling health-care costs. Optimizing the cost-effectiveness of statin therapy is a particular concern to managed care organizations in light of the large number of patients who are now considered candidates for this treatment.

Predictors of long-term persistence on statins in a subsidized clinical population

OBJECTIVES

The use of statins in primary prevention of cardiovascular disease is currently under debate. This study characterizes and identifies predictors of the persistence of use of statins in a clinical cohort of subsidized new users of similar age to the WOSCOPS trial subjects.

METHODS

Medical, pharmaceutical, and demographic records for the period January 1, 1987 through December 31, 1994 were extracted from the databases of Québec's provincial health plan for a 10% random sample of social assistance recipients. Patients remained eligible for inclusion if they had received a first dispensation of a statin between January 1, 1987 and July 31, 1994. Persistence was defined as the number of days on treatment with a statin while continuing to renew dispensations within a defined time limit.

RESULTS

New users of statins included 983 social assistance recipients who were observed for a total of 2,439,153 person-days. Median persistence on statin treatment was 173 (95% CI = 155, 204) days. Only 13% of patients persisted for 5 years of treatment. A higher index of chronic morbidity, pre-existing cardiovascular disease, and previous use of nicotinic acid were predictive of longer persistence on statin medication. Those patients whose first statin dispensation was for lovastatin discontinued treatment earlier than those whose first dispensation was for pravastatin or simvastatin.

CONCLUSIONS

New users showed low persistence on statins in a cohort of socially assisted persons aged 45-64, in spite of the minimal financial cost of the drug for such beneficiaries of Québec's provincial health plan.

Use of lipid lowering drugs for primary prevention of coronary heart disease: meta-analysis of randomised trials

OBJECTIVE

To summarise the effect of primary prevention with lipid lowering drugs on coronary heart disease events, coronary heart disease mortality, and all cause mortality.

DESIGN

Meta-analysis.

IDENTIFICATION

Systematic search of the Medline database from January 1994 to June 1999 for English language studies examining drug treatment for lipid disorders (use of the MeSH terms "hyperlipidemia" and "anticholesteremic agents," keyword searches for individual drug names, and a search strategy for identifying randomised trials to capture relevant articles); identification of older studies through systematic reviews and hand search of bibliographies.

INCLUSION CRITERIA

All randomised trials of at least one year's duration that examined drug treatment for patients with no known coronary heart disease, cerebrovascular disease, or peripheral vascular disease and that measured clinical end points, including all cause mortality, coronary heart disease mortality, and non-fatal myocardial infarctions.

DATA EXTRACTION

Review of the articles and extracted relevant data by two authors separately, with disagreements resolved by consensus.

RESULTS

Four studies met eligibility criteria. Drug treatment reduced the odds of a coronary heart disease event by 30% (summary odds ratio 0.70, 95% confidence interval 0.62 to 0.79) but not the odds of all cause mortality (0.94, 0.81 to 1.09). When statin drugs were considered alone, no substantial differences in results were found.

CONCLUSIONS

Treatment with lipid lowering drugs lasting five to seven years reduces coronary heart disease events but not all cause mortality in people with no known cardiovascular disease.

Pharmaceutical care services and results in project ImPACT: hyperlipidemia

OBJECTIVE

To demonstrate that pharmacists, working collaboratively with patients and physicians and having immediate access to objective point-of-care patient data, promote patient persistence and compliance with prescribed dyslipidemic therapy that enables patients to achieve their National Cholesterol Education Program (NCEP) goals.

DESIGN

Observational study.

PARTICIPANTS

26 community-based ambulatory care pharmacies: independent, chain-professional, chain-grocery store, home health/home infusion, clinic, health maintenance organization/managed care.

MAIN OUTCOME MEASURES

Rates of patient persistence and compliance with medication therapy and achievement of target therapeutic goals.

RESULTS

In a population of 397 patients over an average period of 24.6 months, observed rates for persistence and compliance with medication therapy were 93.6% and 90.1%, respectively, and 62.5% of patients had reached and were maintained at their NCEP lipid goal at the end of the project.

CONCLUSION

Working collaboratively with patients, physicians, and other health care providers, pharmacists who have ready access to objective clinical data, and who have the necessary knowledge, skills, and resources, can provide an advanced level of care that results in successful management of dyslipidemia.