Model-based simulation to explore the cost-effectiveness of following practice guidelines for triglyceride and low-density lipoprotein cholesterol control among patients with diabetes mellitus and mixed dyslipidemia

Background: The National Cholesterol Education Program Adult Treatment Panel III guidelines recommend maintaining lipid levels within particular targets to reduce the risk of coronary heart disease (CHD) events. Objective: The objective of this simulation study was to evaluate the cost-effectiveness of following guideline-recommended care compared with current practice or usual care for patients with diabetes mellitus (DM) and mixed dyslipidemia (ie, high low-density lipoprotein cholesterol [LDL-C] and triglyceride [TG] levels). Methods: A simulation model using a US health care payer perspective was designed to predict changes in lipid levels (LDL-C, TG, high-density lipoprotein cholesterol, and total cholesterol) and long-term CHD risk. Data about patients with DM and uncontrolled TG and/or LDL-C were taken from an electronic medical records database to develop the description of current care (eg, statin, fibrate, or no medication) and cholesterol levels. Patients with uncontrolled lipid levels who were not following guideline recommendations were assumed to be receiving combination treatment (ie, coadministration of statin and fibrate) or monotherapy for the uncontrolled lipids under guideline care. Results from a previous study were used to project incremental benefits of combination treatment compared with monotherapy. CHD events were predicted based on risk equations. A 20-year model of direct costs and quality-adjusted life-years (QALYs) was created. Results: Among patients switched to guideline therapy, the model predicted 72% achieved 2 lipid targets and 44% achieved 3 lipid targets in 1 year. Over 20 years, in a modeled sample of 1000 patients, 176 myocardial infarction and angina events would be avoided by following guideline care. Total present value of costs for drug treatment and medical care for CHD events would be $33,626 per patient for guideline treatment versus $25,264 per patient for current care. The discounted QALY gain would be 0.18 per patient for an incremental cost per QALY of $50,315. Conclusions: The results of this model simulation suggest that for patients with DM and mixed dyslipi-demia, following treatment guidelines rather than current practice (including combination therapy rather than monotherapy) would result in more patients achieving lipid targets, fewer CHD events, and more QALYs gained at a reasonable cost (less than $109,000) per QALY.