The incidence of major adverse cardiac events (MACE) was found to be associated with levels of lipoprotein(a) [Lp(a)] in patients with diabetes who are prescribed statin medications for coronary artery disease (CAD), following percutaneous coronary intervention (PCI), according to study results published in the Journal of Cardiology.
With known proinflammatory and atherothrombotic properties, Lp(a) is a recognized residual risk marker for MACE in individuals with CAD. Statin treatment may increase Lp(a) levels.
In this Japanese single-center, retrospective, observational cohort study, 927 patients with diabetes (mean age, 67 years; 81% men) on statin therapy for CAD were enrolled between 2000 and 2016 after their first PCI. Based on a median Lp(a) level of 19.5 mg/dL, participants were divided into high-Lp(a) levels [n=465; median Lp(a), 34.0 mg/dL] and low-Lp(a) levels [n=462; median Lp(a), 10.0 mg/dL] groups. The primary outcome was the incidence rate of a MACE composite, comprising nonfatal myocardial infarction (MI), nonfatal cerebral infarction (CI), and cardiovascular (CV) death.
Baseline age, sex, body mass index, smoking habits, as well as the prevalence of chronic kidney disease and hypertension were comparable between the high- and low-LP(a) groups. Over a median 5.0 years (interquartile range, 1.9-9.7 years) of follow-up, there were 90 total cases (17.6%) of MACE that included 18 nonfatal MIs (3.6%), 37 nonfatal CIs (7.9%), and 40 cardiac deaths (7.9%).
MACEs occurred more frequently in the high- vs low-Lp(a) group (log-rank test, P =.002). An association between higher Lp(a) levels and MACE incidence was established in an adjusted Cox regression analysis (hazard ratio [HR], 1.83; 95% CI, 1.16-2.95; P =.009). This association was still present MACE frequency in the high- vs low-LP(a) groups using a log-transformed Lp(a) variable (HR, 1.31; 95% CI, 1.03-1.67; P =.026).
Study limitations include its single-center setup, small sample size, observational design, possible unidentified confounders, and a lack of information on patient compliance.
“This study suggests that in patients on statin treatment, Lp(a) should be measured in patients [with diabetes mellitus] and further intervention should be considered,” noted the authors. They recommended that future research further explore the impact of statins on Lp(a) blood levels.
Takahashi N, Dohi T, Funamizu T, et al. Prognostic impact of lipoprotein (a) on long-term clinical outcomes in diabetic patients on statin treatment after percutaneous coronary intervention. J Cardiol. February 2020:1-5. doi:10.1016/j.jjcc.2020.01.013