Implications of 2001 cholesterol treatment guidelines based on a retrospective analysis of a high-risk patient cohort.

In May 2001, the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII) released updated guidelines for the management of serum cholesterol. In these revised recommendations, a modification of the Framingham global risk model is introduced to calculate 10-year risk in certain patient subgroups. Coronary heart disease (CHD) “risk equivalents” (diabetes, multiple risk factors that confer a 10-year risk for CHD of 20%, and other forms of atherosclerotic disease such as peripheral arterial disease, abdominal aortic aneurysm, and symptomatic carotid artery disease) are now included in the highest risk category, with low-density lipoprotein (LDL) cholesterol targets ( 100 mg/dl) the same as for those with documented CHD. There has been speculation that the new guidelines could lead to a tripling of the number of patients who will qualify for lipid-lowering therapy (LLT). Accordingly, we wished to determine the actual change in practice that would be created by the application of ATPIII to a cohort of patients whose treatment had been instituted under ATPII. For this effort, we chose to focus on the issue of initiating LLT for elevated LDL cholesterol. • • • Data were analyzed for 1,501 patients treated in a preventive cardiology practice who were not on LLT at entry, had baseline triglycerides 500 mg/dl, and had sufficient data to calculate 10-year absolute risk per ATPIII recommendations. The algorithms for initiating therapy for elevated LDL cholestserol for primary and secondary prevention of CHD as presented in ATPII and ATPIII, respectively, were applied to this cohort. McNemar’s test for agreement was used to assess differences in treatment recommendations between ATPII and ATPIII. Baseline characteristics for the study population are listed in Table 1. Overall treatment recommendations based on ATPIII versus ATPII were congruent for 87% of the cohort. Of the 13% for whom treatment recommendations were different (p 0.001), 7% moved from “do not treat” under ATPII to “consider treatment” under ATPIII, and 6% moved from “do not treat” under ATP II to “treat” under ATPIII (Table 2). Table 3 lists the qualifying reasons for the 13% with different recommendation under ATPIII. In this retrospective analysis of 1,501 high-risk patients whose treatment had been determined under ATPII guidelines, clinically modest but statistically significant modifications of therapy were mandated by the application of the ATPIII recommendations. An additional 13% of patients who would not have qualified for LLT under ATPII now had definite (6%) or “optional” (7%) indications for therapy. These results support the idea that the application of the ATP III recommendations will “shift the curve,” and augment the number of patients for whom the initiation of LLT is now recommended. On the other hand, the absolute increase in the patient groups that qualified for LLT was surprisingly small. For instance, because patients with “other atherosclerotic disease” (defined by ATPII as peripheral arterial disease or symptomatic carotid artery disease) already qualified for LDL cholesterol targets of 100 mg/dl under ATPII, we speculated that the major changes in ATPIII would be for patients with diabetes From The Cleveland Clinic Foundation, Cleveland, Ohio. Dr. Sprecher’s address is: Preventive Cardiology & Rehabilitation, 9500 Euclid Avenue, Desk C51, Cleveland, Ohio 44195. E-mail: sprechd@ccf.org. Manuscript received October 1, 2001; revised manuscript received and accepted December 3, 2001. TABLE 1 Characteristics of the Study Population (n 1501).