SMuRF-less STEMI patients had significantly higher 30-day all-cause mortality compared to those with ≥1 risk factor (10.7% vs 6.7%; HR 0.82; 95% CI 0.80-0.84; P<0.001).
Cohort (n=379,811)
Yes
Does SMuRF-less status affect short-term and long-term mortality in STEMI patients compared to those with standard modifiable cardiovascular risk factors?
STEMI patients without standard modifiable cardiovascular risk factors face higher 30-day mortality than those with risk factors, partly driven by delayed reperfusion and underutilization of guideline-directed therapy.
Effect estimate: HR 0.82 (95% CI 0.80-0.84)
Absolute Event Rate: 10.7% vs 6.7%
p-value: p=<0.001
Abstract Background In ST-segment elevation myocardial infarction (STEMI) patients, standard modifiable cardiovascular risk factors (SMuRFs) are strongly associated with increased risk of morbidity and mortality. However, clinical studies have shown that SMuRF-less patients have worse clinical outcomes. Limited research exists in China, and the clinical characteristics and prognosis of SMuRF-less patients remain unclear. This study aims to provide insight into the clinical features, treatments, and outcomes of SMuRF-less patients in China. Purpose 1) To assess associations between SMuRF-less status and short-term (30-day)/long-term (1-year) mortality in STEMI patients; 2) To compare treatment patterns and clinical outcomes between SMuRF-less and SMuRFs groups. Methods This retrospective cohort study analyzed 379,811 first-presentation STEMI patients from the Chinese Cardiovascular Association Database-Chest Pain Center (2017–2021). Patients were categorized as SMuRF-less (0 risk factors, n=87,830) or SMuRFs (≥1 risk factor, n=291,981). All-cause and cardiac mortality data were linked to China CDC registries. Multivariable Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals (CIs). Kaplan-Meier curves with landmark analysis (30-day cutoff) evaluated short-term (0–30 days) and long-term (31–365 days) mortality. Sex-stratified analyses examined treatment and outcome disparities. Results Baseline Characteristics: SMuRF-less patients were older (median age: 65 vs. 63 years), more likely female (29.4% vs. 23.3%), and less likely received reperfusion therapy (81.1% vs. 85.6%) compared to SMuRFs patients. SMuRF-less patients had significantly higher short-term all-cause mortality (10.7% vs. 6.7%; adjusted HR: 0.82, 95% CI: 0.80–0.84; P0.001) and cardiac mortality (8.5% vs. 5.4%; HR: 0.83, 95% CI: 0.81–0.86; P0.001). No significant differences were observed between groups on long-term all-cause mortality(3.8% vs. 3.2%; HR: 1.00, 95% CI: 0.96–1.05; P=0.841). Adjusted short-term all-cause mortality reduction was greater in SMuRFs men (HR: 0.75, 95% CI: 0.72–0.78; P0.001) than women (HR: 0.92, 95% CI: 0.88–0.96; P0.001). After excluding 30-day deaths, SMuRF status had no impact on long-term mortality (men: HR: 0.98, 95% CI: 0.92–1.03; women: HR: 1.04, 95% CI: 0.95–1.12). Conclusions SMuRF-less STEMI patients in China face elevated early mortality (notably within 30 days), disproportionately affecting men. Delayed reperfusion and guideline therapy underutilization drive this disparity. Standardized acute care protocols are essential to mitigate excess mortality in this undertreated population.Graphical abstract Flow-chart
Sun et al. (2025) conducted a cohort in ST-segment elevation myocardial infarction (STEMI) (n=379,811). SMuRF-less status (0 standard modifiable cardiovascular risk factors) vs. SMuRFs status (≥1 standard modifiable cardiovascular risk factor) was evaluated on Short-term (30-day) all-cause mortality (HR 0.82, 95% CI 0.80-0.84, p=<0.001). SMuRF-less STEMI patients had significantly higher 30-day all-cause mortality compared to those with ≥1 risk factor (10.7% vs 6.7%; HR 0.82; 95% CI 0.80-0.84; P<0.001).