Adiponectin and insulin resistance are related to restenosis and overall new PCI in subjects with normal glucose tolerance: the prospective AIRE Study

Background: In patients with Normal Glucose Tolerance (NGT) some causes of ischemic heart disease (IHD) were not completely investigated. The role both of metabolic milieu and adipokines in IHD progression was not fully investigated. Our aim was to assess the link between adipokines plasma levels, insulin resistance (IR) and IHD in NGT patients undergoing Percutaneous Coronary Intervention (PCI).

Methods: AIRE is a single-center prospective longitudinal observational study investigating the IHD outcome of NGT subjects who underwent coronary revascularization by PCI in a third level cardiology center at A.O. dei Colli Hospital, University of Campania "Luigi Vanvitelli". Six hundred seventy-nine subjects hospitalized in 2015 for coronary arteriography not suffering from Acute Coronary Syndrome (ACS) in the previous 4 weeks, as well as from all conditions could affect glycemic plasma levels and IR status, were assessed for eligibility. Fifty-four patients with neither history of diabetes nor Altered Fasting Glucose (AFG)/Impaired Fasting Glucose (IGT) after Oral Glucose Tolerance Test (OGTT) were finally enrolled. Primary endpoint was the assessment of the relationship of adipokines and HOMA-IR with the occurrence of restenosis in NGT subjects. As secondary endpoint we assessed the association of the same adipokines and IR with overall ACS events after PCI in NGT subjects.

Results: The 54 NGT patients enrolled were mainly males (85%), with a median age of 60 years [IQR 58-63 years]. Only 4 patients (7.4%) experimented restenosis. Median follow-up was equal to 29.5 months [IQR 14.7-34 months]. Adiponectin levels were independently associated to restenosis (OR 0.206; 95% CI 0.053-0.796; p = 0.000). Instead HOMA-IR and adiponectin appeared independently associated both to de novo IHD (OR 9.6*10¹³; 95% CI 3.026-3.08*10²⁷; p = 0.042 and OR 0.206; 95% CI 0.053-0.796; p = 0.000, respectively) and overall new PCI (OR 1.5*10¹¹; 95% CI 2.593-8.68*10²¹; p = 0.042 and OR 0.206; 95% CI 0.053-0.796; p = 0.000, respectively). Moreover, we fixed a potential cut-off for adiponectin for risk of restenosis (≤ 8.5 µg/mL) and overall new PCI (≤ 9.5 µg/mL).

Conclusion: IR and cytokines play a role in progression of any stage of IHD also in NGT subjects. Our results in this setting of patients, though the relatively small sample size, represent a novelty. Future studies on larger populations are needed to analyze more in depth adipokines and insulin resistance role on IHD progression in non-diabetic people.