Material and methods
Patients and study design
We retrospectively reviewed 102 consecutive Japanese patients diagnosed with ACS who underwent emergent percutaneous coronary intervention in the Department of Cardiovascular Medicine at Tokushima University Hospital between January 2009 and June 2014. The patients were stratified into 3 groups according to age (≤50, 51–74, and ≥75 years) and analyzed.
Because all patients aged ≤50 were male, we moreover performed subgroup analyses after excluding all female patients, resulting in a total of 73 male patients out of the total 102 ACS patients being included in the analyses.
ACS included AMI and unstable angina. AMI was defined as a transient increase of the MB fraction of creatine kinase to a threshold of 3 times the 99th percentile of the upper reference limit (150 U/ L) after percutaneous coronary intervention in patients with ischemic symptoms and/or typical electrocardiographic findings (ST elevation) [7]. Unstable angina was defined as angina at rest, accelerated exertional angina combined with typical electrocardiographic changes (ST depression), or an increase in the intensity of anti-ischemic therapy with a transient increase of the MB fraction of creatine kinase to a threshold of less than 3 times the 99th percentile of the upper reference limit, as described previously [5]. The exclusion criteria were as follows: use of fish oil supplements or n-3 fatty acid-containing drugs. In addition, patients with symptomatic, active malignant diseases or liver dysfunction (aspartate aminotransferase levels >100 IU/L, alanine aminotransferase levels >100 IU/L) were also excluded.