High sdLDL-C Levels Enhance Atherosclerotic Cardiovascular Disease Risk

Ernst J Schaefer, MD

According to the results, when small dense low-density lipoprotein cholesterol (sdLDL-C) value levels reach 50 mg/dL or higher, it’s associated with a 50% increased 10-year inclusive atherosclerotic cardiovascular disease (ASCVD) risk. This applied to all participants regardless of sex or race, which makes it an important atherosclerotic cardiovascular disease risk enhancer.

The study, “Atherosclerotic Cardiovascular Disease Risk and Small Dense Low-Density Lipoprotein Cholesterol in Men, Women, African Americans and Non-African Americans”, was conducted by a team of investigators led by Ernst J Schaefer, MD, Tufts University. It was presented at American Heart Association Scientific Sessions 2021.

Investigators predicted that small dense low-density lipoprotein is an independent atherosclerotic cardiovascular disease risk factor in both men and women as well as African American people and non-African American people.

The Outcome

The standard risk factors measured in this study were significant for hard and inclusive atherosclerotic cardiovascular disease in men, women, African American people and non-African American people on univariate statistical analysis.

Investigators found that when added to the pooled cohort equation for hard and inclusive atherosclerotic cardiovascular disease, small dense low-density lipoprotein was a significant risk factor in all subjects, as well as inclusive atherosclerotic cardiovascular disease in all subgroups.

The hazard ratios (HR) and confidence intervals (CI) for incident inclusive atherosclerotic cardiovascular disease were all significant when patients with elevated small dense low-density lipoprotein levels of ≥50 mg/dL were compared to patients with optimal levels of <25 mg/dL after adjustment for all standard risk factors.

The significant hazard ratios and confidence intervals were all significant at P<0.01: all patients (HR 1.54, CI 1.30-1.83), men (HR 1.59, CI 1.27-1.99), women (HR 1.51, CI 1.05-1.27), non-African American patients (HR 1.49, CI 1.24-1.80[CLA3]), and African American patients (HR 1.88, CI 1.23-2.89).

The Evaluation

The participants were pooled from 3 studies and all free of inclusive atherosclerotic cardiovascular disease at baseline. The median age of the 15,933 participants was 62 years. 56.7% of participants were female, 19.7% of participants were African American.

Patients were analyzed for 10 years for incident hard ASCVD and inclusive ASCVD. Angioplasty (6.1%) and coronary artery bypass (9.7%) were also included.

At baseline, an automated analysis measured serum small dense low-density lipoprotein cholesterol levels and all risk factor information was gathered.

Traditional cardiovascular risk factors and small dense low-density lipoprotein cholesterol levels were examined in 10-year hard and inclusive atherosclerotic cardio vascular disease risk by using a univariate and multivariate regression analysis.

Investigators found that a 50% increased 10-year inclusive atherosclerotic cardiovascular disease risk was associated with small dense low-density lipoprotein cholesterol values that reach 50 mg/dL or higher among all participants, regardless of sex or race.