To evaluate the independent association between RCRI scores and 90-day all-cause mortality in patients undergoing non-cardiac surgery.
Approach:
Study Design: Retrospective cohort study using data from 54,933 adult patients who underwent non-cardiac surgery at a tertiary care center in Singapore between 2012 and 2016.
Data Analysis: RCRI scores were calculated based on six clinical variables and categorized into four classes. Survival analysis was performed using Kaplan–Meier curves and multivariable Cox proportional hazards models.
Key Findings:
735 patients (1.3%) died within 90 days postoperatively.
Higher RCRI classes were associated with significantly poorer survival (log-rank p < 0.001).
Hazard ratios for 90-day mortality were 1.97 (95% CI: 1.54–2.52) for Class II, 1.93 (95% CI: 1.45–2.58) for Class III, and 3.08 (95% CI: 2.29–4.15) for Class IV compared to Class I (p for trend <0.001).
Subgroup analyses confirmed consistent associations across age, sex, ASA class, and surgical priority groups.
Interpretation:
Higher RCRI scores are independently associated with increased 90-day mortality after non-cardiac surgery, indicating a dose–response relationship.
Limitations:
The study is retrospective and may be subject to biases inherent in such designs.
Data was collected from a single tertiary care center, which may limit generalizability.
Conclusion:
The findings indicate the association of RCRI with 90-day all-cause mortality in patients undergoing non-cardiac surgery.
