Study: More ‘good’ cholesterol doesn’t reduce CVD risk if ‘bad’ cholesterol stays same
New research suggests greater amounts of high-density lipoprotein (HDL) cholesterol don’t cut the risk of cardiovascular disease (CVD) when low-density lipoprotein (LDL) cholesterol levels stay the same.
The study implies pharmacological approaches to inhibit cholesteryl ester transfer protein (CETP)—which increase levels of “good” cholesterol—may not be worthwhile unless LDL cholesterol levels drop.
Lead researcher Iona Y. Millwood, DPhil, with the University of Oxford in England, and colleagues studied a cohort of 151,217 Chinese adults and assessed the relationship of five CETP genetic variations linked to higher HDL levels and the corresponding risk of CVD. The mean LDL level for the study population was 91 and the mean HDL level was 48. About 58 percent of the study cohort was women and the mean age of the population was 52.3.
Individuals with CETP variants showed significantly higher HDL readings but similar LDL levels when compared to the rest of the cohort. They also had similar risk of CVD over the median 9.2 years of follow-up.
“These results suggest that in the absence of reduced LDL cholesterol levels, increasing HDL cholesterol levels by inhibition of CETP may not confer significant benefits for CVD,” Millwood and co-authors wrote in JAMA Cardiology.
The researchers noted previous studies of European individuals have shown CETP variants to be associated with both lower LDL levels and a reduced risk of CVD.
“The association of common CETP variants with LDL cholesterol levels in the present study were consistent with other studies in East Asians but directionally different from previous studies in Europeans,” they wrote. “Differences in LDL cholesterol level measurement methods may have contributed to such discrepancies because most previous studies contributing to the large European consortia estimated LDL cholesterol level using the Friedewald formula in contrast to the present study, which measured LDL cholesterol level directly.”
Millwood et al. also pointed out pharmacological CETP inhibitors may work more powerfully than genetic variations, so it’s possible HDL cholesterol levels raised to an extent unmatched by genetic variations may lead to different outcomes. In addition, drugs may be able to lower LDL levels more than CETP variants.
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.