Impact of lipid-lowering therapy on the prevalence of dyslipidaemia in patients at high-risk of cardiovascular events in UK primary care - a retrospective database study

Abstract

Aims: To estimate the prevalence of dyslipidaemias in high-risk patients new to lipid-modifying therapy (LMT), and establish the extent to which these lipid abnormalities are addressed by treatment in UK clinical practice.

Methods: The PRIMULA study was a retrospective analysis, conducted using the UK General Practice Research Database. Two periods were studied as follows: a pretreatment period, defined as the 12 months before initiation of LMT (the index date), and a follow-up period of at least 12 months. Patients included in the study (n = 25,011) had dyslipidaemia with at least one abnormal lipid measurement [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) or triglycerides (TG)] in the pretreatment period. All patients were at high risk of cardiovascular events, which was defined as having a history of cardiovascular disease, a 10-year Framingham risk score higher than 20%, diabetes or hypertension, as defined by the Joint British Societies 2 guidelines.

Results: At the index date, 98% of patients were initiated on statin monotherapy. After 12 months of treatment, 15.2% (sub-group range: 11.0-22.9%) of all high-risk patients had no lipid abnormalities. The proportions of patients with high TC or LDL-C levels decreased from 98.8% to 68.9%, and from 99.2% to 68.7%, respectively, over 12 months. The prevalence of high TG levels decreased from 45.0% to 26.9%, whereas that of low HDL-C levels increased, from 16.6% to 18.0%. Risk factors for cardiovascular events were not consistently associated with the likelihood of attaining optimal lipid levels.

Conclusions: Despite widespread use of statins, many individuals at high risk of cardiovascular events have persistently abnormal lipid levels, with over two-thirds of patients not achieving target levels of LDL-C or TC. Management of dyslipidaemia is therefore suboptimal in this important high-risk group in UK standard practice.