Low-density lipoprotein cholesterol goal attainment in high-risk family medicine patients

Background

The Adult Treatment Panel III guideline recommends a low-density lipoprotein-cholesterol (LDL-C) goal of <100mg/dl for patients with coronary heart disease or risk equivalence (ie, other forms of atherosclerotic vascular disease [peripheral vascular disease, abdominal aortic aneurysm, cerebrovascular disease], diabetes). An optional LDL-C goal of <70mg/dl is recommended for patients considered “very high risk.” This category is not well defined, and clinical interpretation of this category varies.

Methods

To define this category and to determine eligibility for an LDL-C goal of <70mg/dl, 5 definitions of “very high risk” were developed. Patients with coronary heart disease or risk equivalence within the University of Colorado Family Medicine system over the course of 2 years were identified using International Classification of Diseases, 9th Revision codes (n=445). Their medical records were evaluated retrospectively. Patients characterized as “very high risk” according to the 5 definitions were assessed for LDL-C <70mg/dl goal attainment.

Results

Twenty-seven patients did not have LDL-C measurements and were excluded. Using the 5 definitions, we discovered that prevalence as “very high risk” was 10.8% (atherosclerotic vascular disease [AVD] plus smoking), 19.1% (AVD plus diabetes), 21.5% (AVD plus metabolic syndrome plus uncontrolled hypertension or smoking), 47.1% (AVD plus metabolic syndrome), and 67.2% (All AVD), P < .0001. LDL-C <70mg/dl was attained in 26.7%, 46.3%, 31.1%, 39.1%, and 35.2%, respectively (P=.13).

Conclusion

Classifying patients as “very high risk” is highly variable depending on individual definitions, but this does not appear to alter the rates of attaining an LDL-C goal of <70mg/dl. When the Adult Treatment Panel IV guidelines are developed and issued, simplicity and clarity will be important in assisting clinicians in defining patient risk and developing LDL-C goals.

Keywords: Ambulatory care, Atherosclerotic vascular disease, Coronary artery disease, Hydroxymethylglutaryl-CoA reductase inhibitors, Low-density lipoprotein