(52) Statins and LDL-Cholesterol Control in The Long-Term: A Retrospective Cohort Study Using Electronic Health Records

Publication Number: 726

Background: Statins are associated with cardiovascular disease risk reduction due to their direct effect on low-density lipoprotein cholesterol (LDL-C) levels. However, most evidence comes from clinical trials performed during relatively short time periods (≤5 years); thus, the long-term impact of statin treatment on LDL-C change has barely been studied. Likewise, long-term differences in the statins-induced LDL-C reduction between genders and dosages are practically unknown.

Objectives: To evaluate the immediate change in LDL-C (first 3 months of treatment) and the LDL-C long-term control (up to 10 years) after statins treatment initiation in people prescribed statins regularly.

Methods: Retrospective cohort study. Using UK primary care data (The Health Improvement Network) from >500 general practices, we evaluated individuals aged 35 to 99 between 2008 and 2018 who were prescribed statins regularly. We performed an interrupted time series (ITS) analysis. We modelled LDL-Cholesterol change over time using continuous linear splines with random intercept and slopes models, from which three slopes of LDL-Cholesterol change were estimated for 1) –10 years to baseline (first statin prescription) (pre-treatment: β1); 2) baseline to +3 months (immediate impact: β2); 3) +3 months to +10 years (long-term control: β3); overall and stratified by gender (women/men) and dose (low/high).

Results: We observed 389,254 patients, 210,470 were men (54.1%) and 178,784 were women (45.9%). People had a median of 7 episodes of continuous statin treatment (interquartile range (IQR) = 13) and the median duration of these episodes was 117.1 days (95%CI: 115.6-118.6). We found that statins initiation reduced, on average, -1.3 mmol/L in the first 3 months of treatment (adjusted for confounders). It represented an immediate control from 3.8 mmol/L to 2.5 mmol/L, on average. In the long term, the LDL-Cholesterol remained controlled, showing an average increment from 2.5 mmol/L to 2.7 mmol/L in 10 years. Women reduced 10% more than men their LDL-Cholesterol in the short term (3 months), and 62% in the long term (up to 10 years). High doses of statins were 21% more effective to reduce LDL-Cholesterol in the short term, and 58% in the long term.

Conclusions: People prescribed statins regularly control their LDL-Cholesterol in the long term. The notable LDL-Cholesterol reduction experienced in the first 3 months of treatment, which usually leads to optimal levels, is typically maintained during the following years. Being women and being prescribed high dose are both factors that benefit LDL-Cholesterol control in the short and long term.