Prevention of coronary heart disease with pravastatin in men with hypercholesterolemia. West of Scotland Coronary Prevention Study Group

The war on cancer

25 years ago, then President Nixon "declared" War on Cancer. In this personal commentary, the war is reviewed. There have been obvious triumphs, for instance in cure of acute lymphocytic leukaemia and other childhood cancers, Hodgkin's disease, and testicular cancer. However, substantial advances in molecular oncology have yet to impinge on mortality statistics. Too many adults still die from common epithelial cancers. Failure to appreciate that local invasion and distant metastasis rather then cell proliferation itself are lethal, obsession with cure of advanced disease rather than prevention of early disease, and neglect of the need to arrest preneoplastic lesions may all have served to make victory elusive.

Effectiveness and safety of low-dose pravastatin and squalene, alone and in combination, in elderly patients with hypercholesterolemia

A double-blind, placebo-controlled study was conducted to compare the efficacy and safety of low-dose (10 mg) prevastatin and squalene (860 mg), either alone or in combination therapy, with placebo in the treatment of elderly patients with hypercholesterolemia. Ambulatory elderly patients (N = 102) were assigned in randomized fashion to receive active treatment or placebo for 20 weeks after a single-blind placebo lead-in period of 8 weeks. Total cholesterol and triglyceride levels in plasma were at least 250 mg/dL and less than 300 mg/dL, respectively. Concentrations of lipids and lipoproteins were measured, and clinical laboratory tests included liver function and creatine kinase determinations. Pravastatin 10 mg daily was more effective than squalene in reducing total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides and in increasing levels of high-density lipoprotein (HDL) cholesterol. Combination therapy significantly reduced total cholesterol and LDL cholesterol and increased HDL cholesterol to a greater extent than either drug alone. Adverse events and clinical laboratory abnormalities were generally mild and transient in all groups, and all but two patients finished the study. The incidence of side effects was low; myopathy did not occur. Coadministration of pravastatin and squalene combined the specific effects of the two drugs on lipoprotein concentrations. This combination may be useful and more cost-effective in elderly patients with hypercholesterolemia, who might have a higher incidence of side effects when using larger doses of pravastatin alone.

Clinical pharmacologic concepts for the rational selection and use of drugs for the management of dyslipidemia

The long-term clinical benefits of lowering serum lipid levels have been demonstrated in multiple clinical trials in recent years. These include coronary artery disease regression and decreases in the incidence of adverse clinical events, such as myocardial infarction or refractory ischemia. Reductions in overall mortality have also been demonstrated. The health risk of dyslipidemia led the National Cholesterol Education Program expert panel to recommend intervention to bring low-density lipoprotein cholesterol values to within certain goal levels through a variety of interventions. This article reviews the available pharmacologic agents and compares their efficacy, safety, and cost-effectiveness.

Cholesterol-lowering therapy: is there really a controversy?

Geurian concludes that recommendations for the management of hypercholesterolemia are difficult to make because a previously black and white issue is becoming "increasingly gray." Actually, it appears that the opposite is occurring. Our knowledge of atherogenesis, as well as the mechanisms by which thromboembolic events occur, continues to expand. We are gaining new insights into the mechanisms by which cholesterol-lowering therapy can prevent the development of coronary events. Newer cholesterol-lowering agents are more potent than those previously available and make substantial reductions more readily achievable. Finally, we are gaining a better understanding of the relative benefits of cholesterol-lowering therapy in various patient populations, although more work is needed, particularly in women and older patients. Cholesterol-lowering therapy has had an important positive impact on CHD, particularly in preventing recurrent events and reducing mortality when used as secondary prevention. Clearly, there are substantial numbers of patients who will benefit greatly from cholesterol-lowering drugs, and clinicans should not be dissuaded from providing this valuable form of drug therapy.

Heparin-induced extracorporeal low-density lipoprotein precipitation and low-density lipoprotein chemoadsorption onto dextran sulfate: a comparison

Both heparin-induced extracorporeal low-density lipoprotein precipitation (HELP) and dextran sulfate (DS) apheresis are potent tools for acute and long-term risk factor reduction in the secondary prevention treatment of coronary patients suffering from recalcitrant hypercholesterolemia. They combine high efficacy and selectivity of risk factor removal. Whereas LDL cholesterol and lipoprotein (a) adsorption onto DS offers the advantage of an unlimited treatable plasma volume and somewhat easier handling, HELP reduces fibrinogen more effectively and does not interfere with angiotension-converting enzyme (ACE) inhibitors. Both systems can improve blood rheology and induce regression or stabilize coronary lesions. In an uncontrolled trial, HELP reduced the incidence of myocardial infarction. To date, no controlled prospective trials have been performed comparing the two systems with respect to their long-term risk factor reduction and their effect on coronary lesions, morbidity, and mortality.

The 4S study. Implications for prescribing

This article discusses various aspects of cholesterol-lowering therapy using the HMG-CoA reductase inhibitor simvastatin in the light of the large Scandinavian Simvastatin Survival Study (4S). In 4S, patients with proven coronary heart disease (CHD) and plasma total cholesterol > 5.5 mmol/L (212 mg/dl) despite dietary measures received statin therapy or placebo for > or = 5 years. A significant mortality reduction was accomplished in those receiving the statin. Moreover, a significant decrease of nonfatal myocardial infarction and requirement for coronary bypass surgery or angioplasty was demonstrated, which will contribute to the cost-effectiveness of this well tolerated therapy. Plaque stabilisation and improvement of endothelial function are thought to be mediators of this therapeutic success. Responsible drug prescription in the post-4S era may result in the recognition and treatment of more patients with CHD. This is likely to be more beneficial than exhaustive efforts to completely achieve the goals of the most strict guidelines in the individual patient. In patients who carry the highest absolute risk for a recurrent event, aggressive drug therapy may be most justified. Reluctance to initiate lipid lowering drug therapy in patients with proven CHD should now be disputed.

Coronary heart disease risk factors in older persons

In most Western nations, coronary heart disease (CHD) is the leading cause of death and one of the most important causes of physical disability in persons over 65 years of age. The importance of traditional CHD risk factors has been well documented in middle-aged populations, whereas their role in older populations is still under debate. This paper reviews the epidemiologic evidence from observational studies and randomized clinical trials that established risk factors for CHD predict level of risk of CHD, and identify high risk individuals among older men and women. Hypertension and cigarette smoking have been clearly associated with an increased risk of CHD events, and their modification has been proven to be highly effective in the primary and secondary prevention of CHD in older persons. For other highly prevalent risk factors, such as lipid abnormalities, obesity and physical inactivity, evidence of an independent association with CHD risk has been demonstrated by the majority of observational studies. However, definitive proof from controlled clinical trials of the beneficial effects of their modification is still lacking in the older population. The role of estrogen replacement therapy in the primary and secondary prevention of CHD in old women is still an open question. In evaluating the impact of these risk factors in older persons, elements such as comorbidity, frailty, and age-related changes in risk profile should also be taken into consideration. Given the complexity of the relationship between risk factors and multiple disease statuses, other important outcomes, such as osteoporosis, cancer, falls and physical disability, should be considered when evaluating the risks and benefits of risk factor modifications in older persons.

Lipid screening in an elderly population: difficulty in interpretation and in detection of occult metabolic disease

AIMS

To determine lipid profiles and associations with other metabolic disease in a representative British elderly population.

METHODS

Part of a prevalence survey of dementia in all 75+ year olds conducted from the large general practice serving the town and surrounding area of Melton Mowbray, Leicestershire (the M-old study). Patients (n = 224) aged from 75 to 98 years, and representative of the overall population, also provided pre-prandial blood samples on which various age and nutrition related analytes were determined. These included documented medical history, thyroid stimulating hormone (TSH), glucose, immunoglobulins, and lipid profile in plasma.

RESULTS

Cholesterol and lipid variables showed wide scatter, with some negative trends but no significant associations with age for total cholesterol, high density lipoprotein (HDL) cholesterol, the ratio of total to HDL cholesterol or triglycerides. Women had significantly higher concentrations of total and HDL cholesterol at all ages. Serum TSH was above 6.0 mU/1 in 10/205 patients, random glucose was above 11.2 mmol/l in nine of 207 patients, borderline dysglobulinaemia was present in four of 210 patients, all without correlation with cholesterol concentrations.

CONCLUSION

This British data is consistent with an inverse correlation between survival and cholesterol, but wide scatter restricts reliance on single result lipid data in individual patient management. Random lipid screening is also unhelpful, inefficient and without added value in revealing other age related and unrecognised occult metabolic disease.

Anticholesterol antibodies and plaque formation

Immunization of rabbits with a protein-free formulation consisting of liposomes containing 71% cholesterol and lipid A induced cholesterol antibodies in rabbits fed a diet containing 0.5% and 1.0% cholesterol. Elevation in plasma cholesterol levels was significantly less in immunized than in nonimmunized rabbits. Immunization also resulted in a marked decrease in the risk of developing atherosclerosis as determined by analysis of aortic atherosclerosis by quantitative histological examination and fatty streaks by automated morphometric probability-of-occurrence mapping.

A systematic review of the effectiveness of health service interventions aimed at reducing inequalities in health

OBJECTIVE

To review the available evidence in order to identify effective interventions which health services alone or in collaboration with other agencies could use to reduce inequalities in health.

METHODS

A search of the literature was undertaken using a number of databases including Medline (from 1990), Applied Social Science Index and Abstracts (1987-1994), and the System for Information on Grey Literature in Europe (1984-1994), on a large range of key words. Studies were included if they assessed interventions designed to reduce inequalities in health or improve the health of a population group relevant to the review, and could be carried out by a health service alone or in collaboration with other agencies. Only studies evaluating interventions using an experimental design were included. Papers in any language were considered. In addition, systematic reviews of the research on the effectiveness of health promotion and the treatment of conditions where there are significant health inequalities were identified in order to illustrate the potential for reducing inequalities in health.

RESULTS

94 studies were identified which satisfied all the inclusion criteria and 21 reviews were included. A number of interventions have been shown to improve the health of groups who are disadvantaged by socio-economic class, ethnicity or age and, if properly targeted, could be expected to reduce health inequalities. If a health intervention is being used, there should be evidence that it has an impact on health status. Attention should then be given to the way in which the intervention is delivered and the characteristics of a programme to promote implementation. Characteristics of successful interventions specifically aimed at reducing health differentials include: systematic and intensive approaches to delivering effective health care; improvement in access and prompts to encourage the use of services; strategies employing a combination of interventions and those involving a multi-disciplinary approach; ensuring interventions address the expressed or identified needs of the target population; and the involvement of peers in the delivery of interventions. However, these characteristics alone are not sufficient for success, nor are they universally necessary.

CONCLUSIONS

Although it is likely that the most significant contributions to reducing health inequalities will be in improving economic and social conditions and the physical environment, there are interventions which health services, either alone or in collaboration with other agencies, can use to reduce inequalities in health.

Fluvastatin: a review of its pharmacology and use in the management of hypercholesterolaemia

Fluvastatin, a member of the group of drugs known as HMG-CoA reductase inhibitors, is used in the treatment of patients with hypercholesterolaemia. In clinical trials in patients with primary hypercholesterolaemia, fluvastatin 20 or 40 mg/day achieved marked reductions from baseline in serum levels of low density lipoprotein (LDL)-cholesterol (19 to 31%) and total cholesterol (15 to 21%), along with modest declines in serum triglyceride levels (1 to 12%) and small increases in high density lipoprotein (HDL)-cholesterol levels (2 to 10%). These beneficial effects on the serum lipid profile were similar to those demonstrated with other HMG-CoA reductase inhibitors, although direct comparative trials are limited. Concomitant administration of fluvastatin plus another lipid-lowering agent, such as a bile acid sequestrant, a fibrate or nicotinic acid, usually reduced serum levels of total cholesterol and LDL-cholesterol by at least a further 5 to 10% from baseline compared with fluvastatin monotherapy. Fluvastatin has a similar tolerability profile to that of other HMG-CoA reductase inhibitors. Gastrointestinal disturbances, which are usually mild and transient, were the most frequently reported adverse events with fluvastatin in clinical trials. Persistent elevation of serum transaminase levels occurred in approximately 1% of fluvastatin recipients, which is similar to the rate for other HMG-CoA reductase inhibitors. Unlike other HMG-CoA reductase inhibitors, which have been infrequently associated with myopathy and rarely with rhabdomyolysis, these events have not been associated with fluvastatin to date, although fluvastatin has not been used as extensively as agents such as lovastatin. HMG-CoA reductase inhibitors other than fluvastatin, when given in combination with drugs such as fibrates, nicotinic acid, cyclosporin or erythromycin, can increase the risk of these potentially serious adverse events. Thus far, myopathy or rhabdomyolysis have not been reported among patients receiving fluvastatin concomitantly with any of these drugs. Therefore, fluvastatin can be given with caution in combination with fibrates, nicotinic acid, cyclosporin or erythromycin. In conclusion, fluvastatin has similar efficacy and tolerability profiles to other HMG-CoA reductase inhibitors, which are among the most effective agents available for treating patients with hypercholesterolaemia. Pharmacoeconomic studies performed to date suggest an advantage for fluvastatin over other HMG-CoA reductase inhibitors, predominantly because of its relatively low acquisition costs (at least in those countries in which the evaluations were conducted). Thus, fluvastatin is effective and well tolerated in patients with hypercholesterolaemia and appears to have an economic advantage over other HMG-CoA reductase inhibitors, primarily as a result of its relatively low acquisition costs.

Treating elevated cholesterol levels: the great Satan in perspective

The purpose of this review is to provide perspective on the developments leading to the recognition of high cholesterol levels as a risk factor for coronary heart disease (CHD). Another objective is to consider the unfolding controversies regarding the relative value of cholesterol-lowering drug therapy in primary and secondary prevention. Should physicians use lipid-lowering drugs to treat patients with elevated cholesterol levels but no clinical evidence of coronary disease, or limit intervention to patients with a previous history of angina, coronary angioplasty, coronary artery bypass surgery, or myocardial infarction? This review finds inadequate data to support a recommendation for screening large populations for the presence of elevated cholesterol levels or for primary prevention in those known to have high cholesterol. On the other hand, there is mounting evidence to support vigorous intervention in those with known coronary disease. Further study is needed to determine whether a subset of patients with one or more well-defined risk factors would benefit from primary prevention.

A coronary primary intervention study of Japanese men: study design, implementation and baseline data. The Kyushu Lipid Intervention Study Group

This report describes the design and baseline results of the Kyushu Lipid Intervention Study (KLIS). The study aims to test the hypothesis that the long term reduction of serum total cholesterol by pravastatin will lead to a decrease in coronary heart disease (CHD) events. The trial was designed to include a random 6,000 male patients aged 45-74 years with serum total cholesterol of 220 mg/dl (5.69 mmol/l) or greater and without a history of myocardial infarction, coronary surgery or angioplasty, to undertake either pravastatin or conventional treatment (including hypolipidemic drugs other than HMG CoA reductase inhibitors, probucol and bezafibrate), and to follow up each patient for 5 years. Primary endpoints are fatal and nonfatal myocardial infarction, coronary bypass surgery and angioplasty, cardiac death, and sudden and unexpected death. During the period from May 1990 to September 1993, a total of 5,640 male patients aged 45-74 were recruited by 902 participating physicians throughout Kyushu. Randomization was, however, neglected by study physicians; the numbers of patients enrolled were 3,061 in the pravastatin group and 2,579 in the conventional treatment group. Patients allocated to the pravastatin treatment were generally unfavorable regarding coronary risk factors. Baseline mean levels of serum total cholesterol were 259 mg/dl (6.70 mmol/l) in the pravastatin group and 246 mg/dl (6.36 mmol/l) in the conventional treatment group (p <0.001). Although the trial was regarded as a prospective observational study, the KLIS provides valuable quantitative data regarding cholesterol lowering and reduction in CHD events as well as safety data of the long-term use of a statin in Japanese men with hypercholesterolemia.

Benefits and risks of HMG-CoA reductase inhibitors in the prevention of coronary heart disease: a reappraisal

Although several cholesterol-lowering interventions have reduced coronary heart disease (CHD) events in clinical trials, drug therapy for hypercholesterolaemia has not been as widely used as the US and European guidelines recommend, mainly because until recently there was insufficient clinical trial evidence for improved survival. The Scandinavian Simvastatin Survival Study (4S) is the first trial of lipid-lowering therapy to demonstrate an unequivocal reduction in total mortality. Largely as a result of this study, there is now little disagreement on the necessity to reduce low density lipoprotein (LDL) cholesterol effectively in hypercholesterolaemic patients with CHD. Many physicians believe it is also important to reduce elevated levels of LDL cholesterol in patients without overt coronary disease, but more clinical trial evidence will be required before this is universally accepted. Inhibitors of HMG-CoA reductase are the most effective class of agents for this purpose, and have become widely used. It is likely that the magnitude of risk reduction produced by lipid-lowering therapy is proportional to the degree of cholesterol lowering achieved, which is an important consideration when selecting an agent and deciding the dosage to use. The results of several multicentre comparative trials have clearly established that the 4 members of the class are not all equipotent on a mg basis in terms of their effects on lowering LDL cholesterol. They have shown that the hypolipidaemic effect of simvastatin 5 mg approximately equals that of pravastatin 15 mg and lovastatin 15 mg and that of fluvastatin 40 mg, all given once daily. The tolerability profiles of HMG-CoA reductase inhibitors are excellent. Five-year data are available for simvastatin and lovastatin, and to date there is no good evidence for important differences in safety or tolerability among the class.

Automated serial ECG comparison based on the Minnesota code

The Minnesota code was introduced in 1960, and since then, a number of computer programs have been written for classifying electrocardiograms according to the rules of the code. However, in 1982, extended rules for serial comparison based on the Minnesota code were published. This article presents the details of implementation of automated serial electrocardiographic comparison using the code. Its application in the West of Scotland Coronary Prevention Study, which was a double-blind trial of lipid lowering in 6.595 men, is also discussed.