The Impact of Subclinical Hyperthyroidism on Cardiovascular Prognosis in Patients Undergoing Percutaneous Coronary Intervention

Context: Limited studies have focused on the impact of subclinical hyperthyroidism (SHyper) on poor prognosis in patients with known coronary artery disease (CAD).

Objective: We implemented the present study to explore the association between SHyper and adverse cardiovascular events in CAD patients who underwent drug-eluting stent implantation.

Methods: We consecutively recruited 8283 CAD patients undergoing percutaneous coronary intervention (PCI). All subjects were divided into 2 groups according to their thyroid function: group 1 (euthyroidism group, n = 7942) and group 2 (SHyper group, n = 341). After 1:4 propensity score (PS) matching, 1603 patients (332 SHyper group and 1271 euthyroidism group) were selected. The primary endpoint was major adverse cardiovascular events (MACEs), a composite of cardiac mortality, nonfatal myocardial infarction (MI), and target vessel revascularization (TVR).

Results: Kaplan-Meier (K-M) survival analyses suggested that there was no significant difference in the primary endpoint and secondary endpoints (MACE: 11.4% vs 8.8%, log-rank P = .124; cardiac death: 1.2% vs 0.9%, log-rank P = .540; nonfatal MI: 5.7% vs 4%, log-rank P = .177; and TVR: 6% vs 4.7%, log-rank P = .303) in the PS-matched population. Cox regression analysis indicated that SHyper was not an independent risk factor for MACEs (HR 1.33, 95% CI 0.92-1.92, P = .127).

Conclusion: SHyper is not independently associated with adverse cardiovascular events in CAD patients undergoing PCI. More studies should be implemented in the future to assess the long-term predictive value of SHyper with thyrotropin levels <0.1 mIU/L for CAD patients undergoing PCI.