Low-density lipoprotein cholesterol and adverse cardiovascular events after percutaneous coronary intervention

Background — After percutaneous coronary interventions (PCIs), patients remain at high risk of developing late cardiovascular events. Although controlling low-density lipoprotein cholesterol (LDL-C) may improve outcomes after PCI, practice guidelines do not have specific recommendations on LDL-C management for this subgroup.

Objectives — The purpose of this study was to evaluate LDL-C testing and levels after PCIs, and to assess the association between LDL-C and longer-term cardiovascular events after PCIs.

Methods — All patients who received their first PCI from October 1, 2011, to September 30, 2014, in Ontario, Canada, were considered for inclusion. Patients who had LDL-C measurement within 6 months after PCI were categorized as: <70 mg/dl, 70 to <100 mg/dl, and ≥100 mg/dl. The primary composite outcome was cardiovascular death, myocardial infarction, coronary revascularization, and stroke through December 31, 2016.

Results — Among 47,884 included patients, 52% had LDL-C measured within 6 months of PCI and 57% had LDL-C <70 mg/dl. After a median 3.2 years, the rates of cardiovascular events were 55.2/1,000 person-years for the LDL-C <70 mg/dl group, 60.3/1,000 person-years for 70 to <100 mg/dl, and 94.0/1,000 person-years for ≥100 mg/dl. The adjusted subdistribution hazard ratios for cardiovascular events were 1.17 (95% confidence interval: 1.09 to 1.26) for LDL-C of 70 to <100 mg/dl, and 1.78 (95% confidence interval: 1.64 to 1.94) for LDL-C ≥100 mg/dl when compared with LDL-C <70 mg/dl.

Conclusions — One in 2 patients had LDL-C measured within 6 months after PCI, and only 57% had LDL-C <70 mg/dl. Higher levels of LDL-C were associated with an increased incidence of late cardiovascular events. Improved cholesterol management after PCI should be considered to improve the outcomes of these patients.