Effectiveness of adherence to lipid lowering therapy on LDL-cholesterol in patients with very high cardiovascular risk: A real-world evidence study in primary care

Atherosclerosis. 2017 Aug:263:36-41. doi: 10.1016/j.atherosclerosis.2017.05.018. Epub 2017 May 20.


Background and aims: Despite management guidelines advocating statin/ezetimibe use in very high cardiovascular risk (CV) conditions, adherence to this therapy is still suboptimal and LDL-C target attainment unsatisfactory. We aimed to investigate the level of adherence to statin/ezetimibe and LDL-C target achievement rates in an unselected very high CV risk population in primary care setting in Italy.

Methods: We performed a retrospective population-based study using the Health Search IMS Health Longitudinal Patient Database (HSD), including adult patients at very high CV risk, newly treated with statin, ezetimibe or their combination, with 3 and 6 months of follow-up.

Results: Although the large majority of patients had previous major CV events (99.9%), only 61% and 55.14% resulted adherent (Proportion of Days Covered, PDC≥80%) after 3 and 6 months, respectively. High adherence entailed almost a three times higher probability to reach the therapeutic LDL-C target (3 months: OR = 2.26 [95% [CI]: 1.88 to 2.72]; 6-months: OR = 2.74 [95% CI: 2.27 to 3.31]). The odds to treat to LDL-C target was greater for simvastatin-ezetimibe fixed combination, simvastatin, atorvastatin and rosuvastatin, in decreasing order. Finally, poor adherence was slightly more prevalent among patients treated with less effective statins, and at both low and maximal dosage regimens.

Conclusions: This population-based study showed that adherence to statin therapy is poor even among patients who have already experienced a CV event. Failure to achieve recommended LDL-C levels appears imputable to the use of moderate doses and low to standard efficacy statins.

Keywords: Adherence to statins; Cholesterol; High cardiovascular risk; Lipid lowering drugs; Low density lipoproteins; Primary care.

MeSH terms

  • Aged
  • Cardiovascular Diseases / blood*
  • Cardiovascular Diseases / drug therapy*
  • Cardiovascular Diseases / prevention & control
  • Cholesterol, LDL / blood*
  • Drug Administration Schedule
  • Ezetimibe / administration & dosage
  • Female
  • Follow-Up Studies
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / administration & dosage*
  • Italy
  • Longitudinal Studies
  • Male
  • Medication Adherence*
  • Middle Aged
  • Primary Health Care
  • Probability
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome


  • Cholesterol, LDL
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Ezetimibe