Kessler-10 Psychological Distress Score Is Independently Associated with SYNTAX I and SYNTAX II Scores in Patients...

Background and Objectives: Psychological distress is common in acute coronary syndrome (ACS), yet its relationship with objective coronary anatomical complexity is incompletely understood. The Kessler Psychological Distress Scale-10 (K10) is a brief self-report instrument that measures non-specific psychological distress over the preceding four weeks. We investigated whether the K10 score is associated with the anatomical SYNTAX I score and the clinical-anatomical SYNTAX II PCI score in patients hospitalized with ACS. Materials and Methods: This prospective, single tertiary-center observational study assessed 865 adult patients with suspected or confirmed ACS between 6 January 2026 and 5 June 2026. After applying predefined inclusion and exclusion criteria, 750 consecutive eligible patients with complete K10, SYNTAX I, and SYNTAX II PCI data were included in the final analytic cohort. The cohort consisted of STEMI in 337 patients (44.9%), NSTEMI in 310 (41.3%), and unstable angina pectoris in 103 (13.7%). The validated Turkish version of the K10 scale was administered after pain control and hemodynamic stabilization, within 24-48 h of admission, by trained study personnel blinded to the final SYNTAX analysis. SYNTAX I and SYNTAX II PCI scores were calculated by two blinded interventional cardiologists. The primary endpoint was SYNTAX I score ≥ 23; the key secondary endpoint was SYNTAX II PCI score ≥ 36, interpreted as a cohort-based high clinical-anatomical risk threshold. Results: Mean age was 61.3 ± 11.6 years, and 543 patients (72.4%) were men. Mean K10, SYNTAX I, and SYNTAX II PCI scores were 23.7 ± 6.7, 22.4 ± 9.5, and 31.2 ± 9.6, respectively. K10 score correlated with SYNTAX I (Spearman rho = 0.417, p < 0.001) and SYNTAX II PCI (rho = 0.348, p < 0.001). Each 5-point increase in K10 was independently associated with SYNTAX I ≥ 23 (extended model-adjusted odds ratio [OR] 1.84, 95% confidence interval [CI] 1.59-2.12; p < 0.001) and SYNTAX II PCI ≥ 36 (extended model-adjusted OR 2.26, 95% CI 1.85-2.75; p < 0.001). K10 predicted SYNTAX I ≥ 23 with an area under the curve (AUC) of 0.706 (95% CI 0.674-0.744; cutoff ≥ 24) and SYNTAX II PCI ≥ 36 with an AUC of 0.693 (95% CI 0.654-0.736; cutoff ≥ 26). Adding K10 to the extended clinical model improved cross-validated AUC for SYNTAX I ≥ 23 from 0.708 to 0.774 and for SYNTAX II PCI ≥ 36 from 0.871 to 0.905; bootstrap optimism-corrected AUCs were 0.754 and 0.899, respectively. The findings remained consistent in sensitivity analyses excluding prior CABG patients, adjusting for psychiatric history/medication use, and evaluating patients whose K10 was completed before angiography. Conclusions: In this prospective ACS cohort, early in-hospital assessment of K10-defined recent psychological distress was independently associated with both anatomical and clinical-anatomical coronary complexity. K10 should not replace angiographic risk scoring, but it may help identify a psychocardiological phenotype characterized by higher coronary disease burden and greater clinical vulnerability.