A Mathematical Representation of the Expert Panel's Guidelines for Nigh Blood Cholesterol Case-finding and Treatment

Abstract

The National Cholesterol Education Program (NCEP) for high blood cholesterol case-finding and treatment recommended discrete treatments according to the results of sequential mea surements of continuous variables (total and low-density lipoprotein cholesterol [LDL-C]). These measurements are subject to intra- and interindividual variability. The authors describe a computer simulation of the NCEP that acknowledges these complexities. The simulation reduces the NCEP into steps, which are represented in a decision tree. The calculation of probabilities at chance nodes takes into account the conditional nature of sequential mea surements of blood cholesterol. The simulation tracks medical resource use and estimates LDL-C reductions within 20 strata, each defining 5% of population distribution for LDL-C. This approach enables a detailed representation of the case-finding process—the sequence of blood cholesterol tests and associated cut-off values that identify individuals needing more intensive evaluation and treatment. Key words: mathematical modeling; screening programs; hypercholesterolemia. (Med Decis Making 1990;10:135-146)

Get full access to this article

View all access options for this article.

References

The Expert Panel. Report of the National Cholesterol Education Program Expert Panel on detection, evaluation, and treatment of high blood cholesterol in adults. Arch Intern Med. 1988;148:36-69.

National Center for Health Statistics. Total serum cholesterol levels of adults 20 to 74 years of age: United States, 1976-1980. Vital and Health Statistics, Series II, No 236 (DHHS Pub No (PHS) 86-1686), May 1986.

Davis CE The effect of regression to the mean in epidemiologic and clinical studies . Am J Epidemiol. 1976;104:493-8.

Knoke JD , Hawkins LD Estimating baseline values of the variable of intervention in a clinical trial . Control Clin Trials. 1985;6:136-45.

Jacobs DR , Barrett-Connor E. Retest reliability of plasma cholesterol and triglyceride: The Lipid Research Clinics Prevalence Study. Am J Epidemiol. 1982;116:878-85.

Neaton JD , Broste S. , Cohen L. , et al. The Multiple Risk Factor Intervention Trial (MRFIT): VII. A comparison of risk factor changes between two study groups. Prev Med. 1981;10:519-43.

Lipid Research Clinics Program : Pre-entry characteristics of participants in the Lipid Research Clinics' Coronary Primary Prevention Trial. J. Chronic Dis. 1983;36:467-79.

Lipid Research Clinics Program : The Lipid Research Clinics Coronary Primary Prevention Trial Results: I. Reduction in incidence of coronary heart disease. JAMA. 1984;251:351-64.

Lipid Research Clinics Program : The Lipid Research Clinics Coronary Primary Prevention Trial Results: II. The relationship of reduction in incidence of coronary heart disease to cholesterol lowering. JAMA. 1984;251:351-64.

10.

Blankenhorn DH , Nessim SA , Johnson RL , et al. Beneficial effects of combined colestipol-niacin therapy on coronary atherosclerosis and coronary venous bypass grafts. JAMA. 1987;257:3233-40.

11.

Kane JP , Malloy MJ , Tun P. , et al. Normalization of low-density-lipoprotein levels in heterozygous familial hypercholesterolemia with a combined drug regimen. N Engl J Med. 1981;304:251-8.

12.

Illingworth DR Mevinolin plus colestipol in therapy for severe heterozygous familial hypercholesterolemia. Ann Intern Med. 1984;101:598-604.

13.

Bollen KA Structural equations with latent variables. New York: John Wiley & Sons, 1989 .

14.

Schervish MJ Multivariate normal probabilities with error bound. Appl Stat. 1984;33:81-94.

15.

Gardner MJ , Heady JA Some effects of within-person variability in epidemiological studies . J Chronic Dis. 1973;26:781-95.

16.

James KE Regression toward the mean in uncontrolled clinical studies. Biometrics. 1973;29:121-60.

17.

Bishop Y. , Fienberg S. , Holland P. Discrete multivariate analysis: theory and practice (chapter 14). Cambridge, MA: MIT Press, 1975.

18.

Garber AM , Littenberg B. , Sox HC , et al. Costs and effectiveness of cholesterol screening in the elderly . Washington, DC: Office of Technology Assessment, Congress of the United States, 1989.

19.

Choice of cholesterol-lowering drugs. Med Lett. 1988;30:84-7.

20.

National Center for Health Statistics and National Heart, Lung, Blood Institute Collaborative Group : Trends in serum cholesterol levels among U.S. adults aged 20 to 74 years—Data from National Health and Nutrition Surveys, 1960 to 1980. JAMA. 1987;257:937-42.

21.

Kottke TE , Gatewood LC , Wu S. , Park H. Preventing heart disease: is treating the high risk sufficient? J Clin Epidemiol. 1988,41:1083-93.

22.

Davis CE , Gordon D. , LaRosa J. , et al. Correlation of plasma high-density lipoprotein cholesterol levels with other plasma lipid and lipoprotein concentrations: The Lipid Research Clinics Program Prevalence Study. Circulation. 1980;62 (suppl IV):IV24-IV30.

23.

Castelli WP , Cooper GR , Doyle JT , et al. Distribution of triglyceride and total, LDL and HDL cholesterol in several populations: a cooperative lipoprotein phenotyping study. J Chronic Dis. 1977;30:147-69.