Background: Leptin is a hormone involved in the regulation of food intake. Previous investigations suggested a correlation between leptin and platelet aggregation. No data are available on relation between leptin and platelet reactivity (PR) and cardiovascular outcome in patients undergoing percutaneous coronary intervention (PCI).
Purpose: We investigate the role of leptin as predictor of high PR and cardiovascular events in patients undergoing PCI.
Methods: 155 PCI patients, enrolled in the study, had preprocedural measurement of PR and plasma leptin levels. These latter were assessed by ELISA. Hyperleptinemia was defined as leptin levels ≥14 ng/ml. PR was evaluated by the point-of-care VerifyNowP2Y12 assay and expressed as P2Y12 reaction units (PRU). Patients were divided in three groups based on PR: low (LPR), normal (NPR) and high (HPR). The follow up lasted 8 years. Primary endpoint was evaluation of leptin levels according to PR groups. Secondary endpoints were incidence of periprocedural myocardial infarction (PMI) and incidence of MACE at long-term follow-up according leptin group.
Results: Leptin plasma levels were significantly different among groups of PR (P=0.047). Leptin levels were significantly higher in HPR (12.61±16.58 ng/ml) compared to LPR (7.83±8.87 ng/ml, P=0.044) and NPR (7.04±7.03 ng/ml, P=0.01) group. Incidence of PMI in general population was 8%. Rate of PMI was higher among hyperleptinemic patients compared with the other group (15.1% vs 6.5%, P=0.22). Long-term follow-up was complete in 140 patients. Patients with hyperleptinemia experienced a significantly higher rate of MACE compared to the normoleptinemic group (HR 2.3; CI 95% 1.14–4.6, P=0.02). These results remained unchanged after adjusting for BMI, hypertension and sex.
Conclusions: The study suggests that high leptin levels are associated with HPR and with a worse clinical outcome in patients treated with clopidogrel undergoing PCI. Further studies are needed to better define the pathophysiological pathways underlying this association.