Elevated levels of plasma inactive stromal cell derived factor-1α predict poor long-term outcomes in diabetic patients following percutaneous coronary intervention.

Background: Since the complication of diabetes mellitus (DM) is a risk for adverse cardiovascular outcomes in patients with coronary artery disease (CAD), appropriate risk estimation is needed in diabetic patients following percutaneous coronary intervention (PCI). However, there is no useful biomarker to predict outcomes in this population. Although stromal cell derived factor-1α (SDF-1α), a circulating chemokine, was shown to have cardioprotective roles, the prognostic impact of SDF-1α in diabetic patients with CAD is yet to be fully elucidated. Moreover, roles of SDF-1α isoforms in outcome prediction remain unclear. Therefore, this study aimed to assess the prognostic implication of three forms of SDF-1α including total, active, and inactive forms of SDF-1α in patients with DM and after PCI.

Methods: This single-center retrospective analysis involved consecutive patients with diabetes who underwent PCI for the first time between 2008 and 2018 (n = 849). Primary and secondary outcome measures were all-cause death and the composite of cardiovascular death, non-fatal myocardial infarction, and ischemic stroke (3P-MACE), respectively. For determining plasma levels of SDF-1α, we measured not only total, but also the active type of SDF-1α by ELISA. Inactive isoform of the SDF-1α was calculated by subtracting the active isoform from total SDF-1α.

Results: Unadjusted Kaplan-Meier analyses revealed increased risk of both all-cause death and 3P-MACE in patients with elevated levels of inactive SDF-1α. However, plasma levels of total and active SDF-1α were not associated with cumulative incidences of outcome measures. Multivariate Cox hazard analyses repeatedly indicated the 1 higher log-transformed inactive SDF-1α was significantly associated with increased risk of all-cause death (hazard ratio (HR): 2.64, 95% confidence interval (CI): 1.28-5.34, p = 0.008) and 3P-MACE (HR: 2.51, 95% CI: 1.12-5.46, p = 0.02). Moreover, the predictive performance of inactive SDF-1α was higher than that of total SDF-1α (C-statistics of inactive and total SDF-1α for all-cause death: 0.631 vs 0.554, for 3P-MACE: 0.623 vs 0.524, respectively).

Conclusion: The study results indicate that elevated levels of plasma inactive SDF-1α might be a useful indicator of poor long-term outcomes in diabetic patients following PCI.

Trial Registration: This study describes a retrospective analysis of a prospective registry database of patients who underwent PCI at Juntendo University Hospital, Tokyo, Japan (Juntendo Physicians' Alliance for Clinical Trials, J-PACT), which is publicly registered (University Medical Information Network Japan-Clinical Trials Registry, UMIN-CTR 000035587).