Non-high-density lipoprotein cholesterol and treatment targets in vascular surgery patients

Low-density lipoprotein cholesterol (LDL) is a known contributing factor to atherosclerotic cardiovascular disease (ASCVD) and a primary therapeutic target for medical management of ASCVD. Non-high-density lipoprotein cholesterol (non-HDL) has recently been identified as a secondary therapeutic target but is not yet widely used in vascular surgery patients. We sought to assess if vascular surgery patients were undertreated per non-HDL therapeutic guidelines.

This was an observational study that used a single-center database to identify a cohort of adult patients who received care from a vascular surgery provider from 01/2001 to 07/2021. ICD-9/10-CM codes were used to identify patients with a medical history of hyperlipidemia (HLD), coronary artery disease (CAD), cerebrovascular occlusive disease (CVOD), peripheral artery disease (PAD), hypertension (HTN), or diabetes mellitus (DM). Patient smoking status and medications were also identified. Lab values were obtained from the first and last patient encounter within our system. Primary outcomes were serum concentrations of LDL and non-HDL, with therapeutic thresholds defined as 70 mg/dL and 100 mg/dL, respectively.

The cohort included 2465 patients. At first encounter, average age was 59.3 years old, 21.4% were on statins, 8.4% were on a high-intensity statin, 25.7% were diagnosed with HLD, 5.2% with CAD, 15.3% with PAD, 26.3% with DM, 18.6% with HTN, and 2.1% with CVOD. At final encounter, mean age was 64.8 years, 23.5% were on statins with 10.1% on high-intensity statin. Diagnoses frequency did not change at final encounter. At first encounter, nearly two-thirds of patients were not at an LDL <70 mg/dL (62.3%) or non-HDL <100 mg/dL (66.0%) with improvement at final encounter to 45.2 and 40.5% of patients not at these LDL or non-HDL treatment thresholds, respectively. Patients on statins exhibited similar trends with 51.1 and 50.1% of patients not at LDL or non-HDL treatment thresholds at first encounter and 39.9 and 35.4% not at LDL or non-HDL treatment thresholds at last encounter. Importantly, 6.9% of patients were at LDL but not non-HDL treatment thresholds.

Among vascular surgery patients, over half did not meet non-HDL targets. These results suggest that we may be vastly under-performing adequate medical optimization with only about one-fourth of patients on a statin at their final encounter and approximately one-tenth of patients being treated with a high-intensity statin. With recent evidence supporting non-HDL as a valuable measurement for atherosclerotic risk, there is potential to optimize medical management beyond current high-intensity statin therapy. Further investigation is needed regarding the risk of adverse events between patients treated with these varied therapeutic targets.