Leptin as predictor of cardiovascular events and high platelet reactivity in patients undergoing percutaneous coronary intervention

Abstract

Background and aims: Leptin is a hormone involved in the regulation of food intake. Previous studies suggested an interplay between leptin, platelet aggregation, and cardiovascular outcome but this issue was not investigated in vivo in patients treated with percutaneous coronary intervention (PCI). We designed a study to evaluate the possible relation between leptin, cardiovascular outcome, and platelet reactivity (PR) in patients undergoing PCI.

Methods: 155 PCI patients had preprocedural measurements of PR and leptin plasma levels. The latter were assessed by ELISA. Hyperleptinemia was defined as leptin levels ≥14 ng/ml. PR was evaluated by the VerifyNowP2Y12 assay and expressed as P2Y12 reaction units (PRU). Patients were divided into three groups based on PR values and defined as low (LPR), normal (NPR), and high (HPR). Patients were followed for up 8 years. The primary endpoint was the incidence of Major Acute Cardiac Events (MACE) at long-term follow-up according to leptin groups. Secondary endpoints were the evaluation of leptin levels according to PR groups and the incidence of periprocedural myocardial infarction (PMI) according to leptin groups.

Results: Long-term follow-up was completed in 140 patients. Patients with hyperleptinemia experienced a higher MACE rate than the normoleptinemic group (HR 2.3; CI 95% 1.14-4.6, P = 0.02). These results remained unchanged after adjusting for Body Mass Index, hypertension, and gender. Leptin levels were significantly different among groups of PR (P = 0.047). Leptin levels were higher in the HPR group (12.61 ± 16.58 ng/ml) compared to the LPR group (7.83 ± 8.87 ng/ml, P = 0.044) and NPR group (7.04 ± 7.03 ng/ml, P = 0.01). The rate of PMI was higher in hyperleptinemia patients (15.1% vs. 6.5%, P = 0.22).

Conclusions: This study suggests that high leptin levels are associated with a worse clinical outcome in patients undergoing PCI and with HPR. Further studies are needed to define better the pathophysiological pathways underlying this association.

Keywords: Cardiovascular events; Cardiovascular outcome; Leptin; Percutaneous coronary intervention; Periprocedural myocardial infarction; Platelet reactivity.