Outcomes of NSTEMI Admissions and Significance of TIMI Scores: A Nationwide Analysis Using the National Inpatient Sample

<b>Background/Objectives</b>: The main aim of this study is to analyze the outcomes of NSTEMI admissions and test the relevance of TIMI as a risk score in a real-world setting. We also examine any potential social or health care disparities involved with outcomes of NSTEMI admissions. This study also investigates factors associated with mortality in NSTEMI admissions and its correlation with heart catheterization during admission. <b>Methods</b>: NSTEMI admissions were analyzed using the National Inpatient Sample. TIMI scores were calculated for the admissions and their association with all-cause mortality was studied. Differences in mortality outcomes based on heart catheterization during admission were studied in the subgroup with a TIMI score > 2. Correlations between time to heart catheterization and all-cause mortality in NSTEMI admissions were analyzed. <b>Results</b>: No significant social or healthcare disparities were noted among outcomes for NSTEMI admissions. NSTEMI admissions with a calculated TIMI score > 2 had a statistically significant association with all-cause mortality during admission: odds ratio 1.33 (95% CI 1.23-1.43, <i>p</i> value: 0.00). The prevalence of mortality among NSTEMI admissions with a calculated TIMI score > 2 who did not undergo heart catheterization was higher with statistical significance (6.23%; 95% CI: 5.84-6.65%), when compared to admissions who underwent heart catheterization (2.41%; 95% CI: 2.25-2.59%). NSTEMI admissions with a calculated TIMI score > 2 who underwent catheterization on or beyond the fourth day of hospitalization had a statistically significant association with all-cause mortality during admission: odds ratio: 2.56 (95% CI: 2.31-2.83, <i>p</i> value: 0.00). Age at admission, presence of CKD and CHF were associated with mortality in NSTEMI admissions, with statistical significance. <b>Conclusions</b>: Based on the results of our analysis, no disparities in terms of race/sex/hospital location, etc., were seen for NSTEMI in-hospital outcomes. Admissions with a TIMI score > 2 had a statistically significant association with in-hospital mortality, after accounting for confounders. Among NSTEMI admissions with a TIMI score > 2, those who did not undergo heart catheterization during admission were found to have a higher prevalence of in-hospital mortality. No social or healthcare disparities were seen among admissions with TIMI score > 2 who did not undergo heart catheterization during admission. We also noted that NSTEMI admissions with a TIMI score > 2 who underwent heart catheterization on or beyond Day 4 of the initial admission were associated with higher mortality.