The Association Between Time of Lipid-Lowering Therapy Initiation and Acute Clinical Presentation Among Patients Admitted With Coronary Artery Disease, and Its Effect on Future Cardiovascular Events: An Australian Observational Study.

Background: Lipid-lowering therapy (LLT) is established as a key element in management of patients with coronary artery disease. However, the effect of time of initiation of LLT on outcomes is unclear.

Method: The study compared outcomes of 5,433 patients from Advara HeartCare's Percutaneous Coronary Intervention (PCI) Registry on the basis of timing of LLT initiation classified as pre- or post-PCI admission. The prevalence of acute coronary syndrome (ACS) as the indication for PCI was compared in groups. In patients who underwent PCI for ACS, the incidence of short- (≤30 days) and long-term (>30 days after admission) clinical events (composite of myocardial infarction, cerebrovascular disease, coronary revascularisation, all-cause readmission, and mortality) and first non-fatal cardiovascular events were compared in groups.

Results: At the time of hospitalisation for PCI, 3,982 (73.7%) were on LLT (PRE-LLT), and 1,418 (26.2%) initiated LLT after admission (POST-LLT). Patients on PRE-LLT were significantly less likely to experience ACS before admission for PCI than were those commencing LLT after discharge (PRE-LLT 32.3% vs POST-LLT 56.9%; p<0.001), even after matching for baseline risk factors. Among these patients with ACS, patients on PRE-LLT were older than those on POST-LLT (mean 69.5±9.5 vs 65.0±10.0 years; p<0.001), and had a higher prevalence of cardiovascular risk factors including diabetes (31.5% vs 9.6%; p<0.001), hypertension (79.7% vs 51.7%; p<0.001), and renal failure (7.6% vs 2.0%; p<0.001). No difference was observed between groups in the risk of short- or long-term (median 2.0 years; interquartile range 1.0-3.0) post-PCI cardiovascular (hazard ratio [HR] 1.08; 0.83-1.40; p=0.55) or overall clinical events (HR 1.11; 0.93-1.32; p=0.26).

Conclusions: In patients with coronary artery disease, the risk of ACS is reduced by early initiation of LLT before revascularisation is required. Long-term outcomes of patients at high risk prescribed LLT before admission for ACS PCI may not differ from those of patients at lower risk commencing LLT after PCI for ACS.