Background: The prevalence of high-density lipoprotein cholesterol (HDL-C) in patients who have achieved low-density lipoprotein cholesterol (LDL-C) targets in the current era of universal statin therapy remains unknown. We conducted a study to determine the prevalence of low HDL-C in patients with documented coronary artery disease, and to determine the lipid-lowering treatment patterns in secondary prevention of coronary artery disease.
Methods: In this retrospective cohort analysis, data were obtained from the electronic database of a cardiology clinic. The Joint British Society 2 criteria were used defining low HDL-C as less than 1 mmol/l in males and less than 1.2 mmol/l in females. We compared the prevalence of low HDL-C across the following categories of LDL-C: less than 2, 2-2.5, and greater than 2.5 mmol/l.
Results: Two thousand and eighty-seven patients with a mean age of 64.34±11.94 years constituted the study sample. About 36.6% of patients in this study were found to have low HDL-C. Irrespective of sex, low HDL-C was prevalent across all levels of LDL-C, but interestingly this was most prevalent in patients with a LDL-C less than 2 mmol/l (43.06%). HDL-C level of 1.16±0.97 mmol/l in patients with LDL-C less than 2 mmol/l was significantly lower than 1.22±0.33 mmol/l in patients with LDL-C greater than 2 mmol/l, P value less than 0.01. There was a poor correlation between levels of HDL-C and LDL-C in the study population irrespective of sex or statin therapy.
Conclusion: This study shows widely prevalent low HDL-C levels in high-risk patients across the spectrum of LDL-C levels despite statin therapy. There was no correlation between the LDL-C and HDL-C levels implying their independent relationship and, thus, the need to treat them independently.