Background: Despite revascularisation, a large proportion of acute coronary syndrome (ACS) patients continue to experience major adverse cardiovascular events (MACEs), which are worsened by diabetes mellitus (DM). Fibrinogen (FIB) is a risk factor for MACEs in coronary artery disease and often elevated in DM. However, the relationships between FIB, glucose metabolism (haemoglobin A1c [HbA1c] and fasting blood glucose [FBG]) and MACEs following percutaneous coronary intervention (PCI) in DM, non-DM or whole patients with ACS remains unknown.
Methods: A total of 411 ACS patients undergoing PCI were enrolled in this study. We compared baseline FIB levels between DM (n = 103) and non-DM (n = 308) patients and divided participants into three groups according to FIB level, i.e. FIB-L, FIB-M and FIB-H, to compare baseline characteristics and MACEs. Linear regression analysis of the relationship between glucose metabolism and FIB, Cox regression, survival and landmark analyses of MACEs were also performed over a median of 27.55 months of follow-up.
Results: Patients with DM had higher FIB levels than non-DM patients (3.56 ± 0.99 mg/dL vs. 3.34 ± 0.80 mg/dL, P < 0.05). HbA1c and FBG were significantly positively correlated with FIB in whole and DM patients but not in non-DM patients (all P < 0.05). Compared with the FIB-L group, the FIB-M (hazard ratio [HR] 1.797, 95% CI 1.117-2.892, P = 0.016) and FIB-H (HR 1.664, 95% CI 1.002-2.763, P = 0.049) groups were associated with higher MACEs in whole; the FIB-M (HR 7.783, 95% CI 1.012-59.854, P = 0.049) was associated with higher MACEs in DM patients. FIB was not associated with MACEs in non-DM patients. During landmark analysis, FIB showed better predictive value for MACEs after PCI in the first 30 months of follow up than in the subsequent period.
Conclusion: In this study from China, FIB was positively associated with glucose metabolism (HbA1c and FBG) in whole and DM populations with ACS. Moreover, elevated baseline FIB levels may be an important and independent predictor of MACEs following PCI, especially amongst those with DM. However, as the follow-up period increased, the baseline FIB levels lost their ability to predict MACEs.
Keywords: Acute coronary syndromes; Diabetes mellitus; Fasting blood glucose; Fibrinogen; HbA1c; Major adverse cardiovascular events; Percutaneous coronary intervention.