Abstract
OBJECTIVE: This study aimed to assess the effects of dexmedetomidine (DEX) on anxiety and inflammation, and its potential in reducing in-hospital adverse events in older patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). METHODS: We conducted a retrospective, real-world cohort study, enrolling 160 elderly patients with STEMI admitted to the cardiac care unit (CCU) between September 2020 and December 2024. Patients were divided into two groups: DEX and non-DEX. Propensity score matching (PSM, 1:1 ratio) was applied based on demographic and clinical variables, ensuring balanced groups for comparison. We evaluated catecholamine and inflammation levels, anxiety using the Amsterdam Preoperative Anxiety and Information Scale (APAIS), and cognitive function at four time points (T0-T3). The incidence of cumulative MACE (20.00% vs 38.8%, P = 0.015) and VT/VF (1.3% vs 10.0%, P = 0.034) was significantly lower in the DEX group compared to the non-DEX group. Multivariable logistic regression was performed to identify risk factors for in-hospital major adverse cardiac events (MACE). RESULTS: The DEX group had significantly lower catecholamine (norepinephrine, P < 0.001; epinephrine, P = 0.001; dopamine, P < 0.001) and inflammation levels (hs-CRP, P < 0.001) post-PCI compared to the non-DEX group. Additionally, heart rate (HR) (T1, P < 0.001; T2, P < 0.001; T3, P = 0.007) and respiratory rate (RR) (T1, P < 0.001; T2, P < 0.001) were lower, while blood oxygen saturation (SpO(2)) (T1, P = 0.045; T2, P < 0.001; T3, P < 0.001; T4, P = 0.016) was higher in the DEX group at various time points. In the DEX group, Ramsay Sedation Scores were higher at T1 (P = 0.007) and T2 (P < 0.001) than at T0, and anxiety scores decreased significantly from T1 (P = 0.021), T1 (P = 0.017) to T3 (P = 0.015) compared with the preceding time point. DEX was identified as an independent predictor of reduced in-hospital MACE [odds ratio (OR) = 0.244, 95% confidence interval (CI) = 0.082-0.728, P = 0.011]. CONCLUSION: DEX was associated with lower catecholamine and inflammation levels, provided adequate sedation, and appeared safety, feasibility, and effectiveness for older patients with STEMI undergoing primary PCI.