Nearly half of patients taking a statin to manage their cholesterol are not achieving their target levels of low-density lipoprotein or ‘bad’ cholesterol (LDL-C), according to new data from an international study sponsored by Merck & Co.

Updated results from the DYSlipidaemia International Study (DYSIS), presented at the European Society of Cardiology (ESC) congress in Barcelona, Spain, showed that 48% of statin-treated patients in the large observational trial had LDL-C levels above target, according to ESC guidelines, while 38% had elevated triglycerides and 25% were below the level of high-density lipoprotein or ‘good’ cholesterol recommended by the ESC.

When Merck & Co presented initial data from DYSIS at the American College of Cardiology (ACC) back in March, it said only 22.8% of the study population were not reaching their LDL cholesterol goal. Moreover, elevated triglycerides and low HDL-C were seen in 38.7% and 31.5% respectively, of statin-treated patients.

According to Merck, the 22.8% non-attainment rate for bad cholesterol seen at the ACC meeting was "the proportion of patients with LDL-C not at goal as the ONLY lipid abnormality. The overall rate of patients not at LDL-C (regardless of whether they had low HDL-C and/or elevated TG in addition) was 38.9%".

The difference between this rate and the 48% presented at the ESC congress was mostly down to varying LDL-C thresholds in the NCEP-ATPIII guideline used for the ACC data and the ESC guideline used for the new data featured in Barcelona, it added.

Even among those patients who attained their LDL-C target, 25% were found in the latest analysis to have abnormal levels of triglycerides and/or HDL-C, Merck noted. Nearly three-quarters or 73% of statin-treated patients overall had at least one lipid abnormality across the LDL-C, HDL-C and triglyceride measures.

The DYSlipidaemia International Study involved 22,000 statin-treated patients across 12 countries in Europe and Canada, with 28 centres taking part in the UK. Patients were aged 45 years and over, had been on statins for three months or more, and had other cardiovascular conditions such as high blood pressure, diabetes, a family history of premature cardiovascular disease or coronary heart disease.

The study assessed the prevalence of LDL-C, HDL-C and triglyceride levels according to the lipid goals in ESC guidelines.

“Although statins have represented a considerable advancement in cardiovascular disease prevention, the DYSIS results indicate that clinicians must continue to monitor their patients' lipid levels closely, including LDL-C, HDL-C and triglyceride levels,” said avid Wood, lead UK investigator and professor of cardiovascular medicine at Imperial College London.

“Many patients could benefit from additional management in order to further reduce their risk of cardiovascular disease, achieved through improved adherence, lifestyle changes, or further drug intervention,” he added.

The results of a nationwide survey released by MSD UK in conjunction with the DYSIS data suggested that much needs to be done still to raise awareness of these issues and how to address them.

Among the 2,140 adults polled, 85% knew that cardiovascular disease was the leading cause of death in the UK and many (71% and 59% respectively) were aware of LDL and HDL cholesterol. However, a majority of the poll did not know ‘how to change’ their LDL-C (57%) or HDL-C (74%), MSD pointed out.

And only 36% had heard of triglycerides, with most (77%) believing they should be raised rather than reduced and 90% not knowing how to change them.