At what level of coronary heart disease risk should a statin be prescribed?

Current Opinion in Lipidology

Volumn 11, Issue 4, 2000, Pages 363-367

  Allan, Gaw ^a   Packard, Chris J ^a  

^a GLASGOW ROYAL INFIRMARY   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

LIPID; MEVINOLIN; PRAVASTATIN; SIMVASTATIN; STATIN;

CARDIOVASCULAR RISK; CLINICAL TRIAL; HEALTH CARE SYSTEM; HIGH RISK PATIENT; HUMAN; ISCHEMIC HEART DISEASE; LIPID BLOOD LEVEL; META ANALYSIS; PREDICTION; PRESCRIPTION; PRIMARY PREVENTION; PRIORITY JOURNAL; REVIEW; RISK ASSESSMENT; SECONDARY PREVENTION; UNITED KINGDOM; VASCULAR DISEASE;

AGE FACTORS; ANTILIPEMIC AGENTS; CLINICAL TRIALS; CORONARY DISEASE; COST-BENEFIT ANALYSIS; FEMALE; GREAT BRITAIN; HUMANS; MALE; RISK FACTORS;

GOES;

EID: 0033868066     PISSN: 09579672     EISSN: None     Source Type: Journal    
DOI: 10.1097/00041433-200008000-00004     Document Type: Review

References (34)

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11. 11 Kessler K. Relative risk reduction in trial results [Letter]. Am J Cardiol 1999; 83:475-476. A useful reminder of the implications of baseline risk and the effect this has on the NNT.
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15. 15 Wallis EJ, Ramsay LE, Haq IU, et al. Coronary and cardiovascular risk estimation for primary prevention: validation of a new Sheffield table in the 1995 Scottish health survey population. BMJ 2000; 320:671-676. A revised version of the Sheffield risk table is presented for the assessment of cardiovascular risk in primary prevention patients. The table incorporates sex, age, smoking status, diabetic status and hypertension as a categorical variable. The total:HDL-cholesterol ratio is included in this table, which was tested in a random sample of 1000 people aged 35-64 years from the 1995 Scottish health survey. The authors conclude that their risk table identifies all high-risk people for lipid screening, reduces the screening of low-risk people by more than half, and ensures that treatments are prescribed appropriately in terms of global cardiovascular risk.
16. 16 Pickin DM, McCabe CJ, Ramsey LE, et al. Cost effectiveness of HMG-CoA reductase inhibitor (statin) treatment related to the risk of coronary heart disease and cost of drug treatment. Heart 1999; 82:325-332.
17. 17 Caro J, Klittich W, McGuire A, et al. International economic analysis of primary prevention of cardiovascular disease with pravastatin in WOSCOPS. Eur Heart J 1999; 20:263-268. The WOSCOPS Economic Group has extended its previously published cost-effectiveness analysis to encompass different countries and different healthcare systems. They show that pravastatin use is both clinically and cost effective across a range of healthcare systems, and conclude that this approach should fit within the bounds set by already accepted therapies in most countries.
18. 18 Pyörälä K, De Backer G, Graham I, et al. Prevention of coronary heart disease in clinical practice. Recommendations of the Task Force of the European Society of Cardiology, European Atherosclerosis Society and European Society of Hypertension. Eur Heart J 1994; 15:1300-1331.
19. 19 Baker S, Priest P, Jackson R. Using thresholds based on risk of cardiovascular disease to target treatment for hypertension: modelling events averted and number treated. Brit Med J 2000; 320:680-685. Although this paper focuses on antihypertensive therapy it has relevance to the closely related topic of cardiovascular risk assessment and statin treatment. The authors studied 2158 subjects and concluded that if treatment guidelines were implemented in practice using treatment thresholds based on the absolute risk of cardiovascular disease, this would significantly improve the efficiency of antihypertensive drug therapy in primary care. If a 3% per annum threshold of risk were adopted this would increase the proportion of patients treated by less than 10%, but would avert a third more events than the current criteria for therapy. If a 2% risk level were chosen this would actually reduce the number of patients currently treated by approximately 10%, yet would still avert 10% more events than achieved by current treatment criteria. This would be achieved principally by decreasing the number of women and middle-aged individuals treated. Clearly, this points to a more efficient and cost-effective strategy and presents a very strong argument for the use of a global risk threshold rather than an absolute value for any single risk factor, be it systolic blood pressure or LDL-cholesterol.
20. 20 Peeters A, Demos LL, McNeil JJ. Should smoking be an indication for lipid-lowering therapy? Med J Aust 1999; 170:240. Here the case for including smoking status in the overall risk assessment to determine the use of lipid-lowering drugs and for the reimbursement of drug costs is made.
21. 21 Colhoun HM, Dong W, Barakat MT, et al. The scope for cardiovascular disease risk factor intervention among people with diabetes mellitus in England: a population based analysis from the Health Surveys for England 1991-94. Diabet Med 1999; 16:35-40. Of those individuals with diabetes aged under 70 years, 29% required lipid-lowering therapy based on the UK standing medical advisory committee guidelines. The authors, however, argue that this figure is likely to be an underestimate as the Sheffield tables used in these guidelines do not incorporate HDL-cholesterol as a continuous variable, and conclude that this will result in women especially being assigned lower risk scores than they really have. The authors also point out that the great majority (94%) of these diabetic individuals eligible for treatment are currently on no lipid-lowering therapy and that there is therefore considerable scope for improvement in our management of the CHD risk of these high-risk patients.
22. 22 Silberberg J. Better coronary risk assessment in women. Lancet 1999; 353:137-138. The author argues for the importance of family history of premature coronary disease in global risk assessment, which is not currently included in any risk assessment tool in routine use. This is a particularly strong risk factor for women.
23. 23 Durrington PN, Prais H, Bhatnagar D, et al. Indications for cholesterol-lowering medication: comparison of risk-assessment methods. Lancet 1999; 353:278-281. In a series of 570 patients, the NCEP Guidelines, the Joint European Guidelines and the Sheffield tables were compared. The authors concluded that different risk-assessment tools associated with different guidelines varied in their assessment of CHD risk and therefore in the treatment strategy proposed. Importantly, a call is made for the rigorous evaluation of any risk-assessment tool before it is introduced into clinical practice.
24. 24 Jackson R. Updated New Zealand cardiovascular disease risk-benefit prediction guide. BMJ 2000; 320:709-710. This paper presents an update of the highly acclaimed and widely used New Zealand tables. These risk assessment tables benefit from the inclusion of diabetes and HDL-cholesterol in the form of a total cholesterol:HDL ratio. The author is, however, eager to point out that these tables are not, in themselves, a guideline for the management of cardiovascular risk, but rather a clear means of assessing it based on the Framingham Heart Study.
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29. 29 Ramachandran S, French JM, Vanderpump MPJ, et al. Using the Framingham model to predict heart disease in the United Kingdom: retrospective study. BMJ 2000; 320:676-677. The authors concluded that the Framingham model reliably predicts the absolute risk of CHD in white men and women in the UK when annual risk is above 1.5%, but underestimates the risk at lower risk levels.
30. 30 Hingorami AD, Vallance P. A simple computer program for guiding management of cardiovascular risk factors and prescribing. BMJ 1999; 318:101-105. A simple computer program for risk assessment based on the Framingham equations is described.
31. 31 Cullen P, Assmann G. High risk strategies for atherosclerosis. Clin Chim Acta 1999; 286:31-45. This review advocated the use of risk assessment algorithms derived from the data from prospective studies such as the Framingham Heart Study or PROCAM. The interactive version of the PROCAM risk algorithm is highlighted and can be found at http://www.chd-taskforce.com.
32. 32 Allison TG, Squires RW, Johnson BD, Gau GT. Achieving National Cholesterol Education Program goals for low density lipoprotein cholesterol in cardiac patients: importance of diet, exercise, weight control, and drug therapy. Mayo Clin Proc 1999; 74:466-473. In 152 patients after an acute coronary event, only 39% achieved the NCEP LDL-cholesterol goal of 100 mg/dl or less after almost 1.5 years of follow-up. Notably, specially trained nurses were found to manage lipids as well (or as badly) as preventive cardiologists. Approximately two-thirds of those achieving the goal required drug therapy.
33. 33 Van der Weijden, Grol RPTM, Knottnerus JA. Feasibility of a national cholesterol guideline in daily practice. A randomized controlled trial in 20 general practices. Int J Qual Health Care 1999; 11:131-137. This Dutch study of 3950 patient records concluded that neither simple dissemination nor an intensive programme for improvement had measurable impact on the actual performance of adherence to a cholesterol guideline. Clearly, the practicalities of implementing any new set of guidelines should be considered during their design and drafting.
34. 34 Shepherd J, Blauw GJ, Murphy MB, et al. The design of a prospective study of pravastatin in the elderly at risk (PROSPER). Am J Cardiol 1999; 84:1192-1197. Important questions that remain regarding the use of statin therapy in the elderly and in primary and secondary prevention of cerebrovascular disease will be addressed by the PROSPER study, a randomised, placebo-controlled double-blind clinical trial of pravastatin in an elderly cohort of approximately 5500 men and women.