January 12, 2006Open Access
View Full PaperOutcomes of patients in clinical trials with ST-segment elevation myocardial infarction among countries with different gross national incomes
Key Result
Lower country gross national income was associated with higher 30-day mortality in STEMI patients compared to high-income countries (observed mortality 12.1% vs 4.9%).
Study Design
Type
Observational (n=50,310)
Multicenter
Yes
Structured PICO
Is there an association between country gross national income and 30-day mortality in patients with STEMI included in clinical trials?
P
Population
50,310 patients with ST-segment elevation myocardial infarction (STEMI) from 5 randomized trials (COBALT, GIK-2, HERO-2, ASSENT-2, and ASSENT-3) across 53 countries
I
Intervention
Residence in countries with different gross national incomes (GNI: low, medium, high)
C
Comparator
Comparison between low, medium, and high GNI countries
O
Outcome
30-day mortalityhard clinical
In STEMI clinical trials, lower income countries have higher 30-day mortality than expected even after adjusting for baseline characteristics.
Main Result
Absolute Event Rate: 12.1% vs 4.9%
Abstract
AIMS: To evaluate whether there is an association between 30-day mortality in patients with ST-segment elevation myocardial infarction (STEMI) included in clinical trials and country gross national income (GNI). METHODS AND RESULTS: A retrospective analysis of the databases of five randomized trials including 50 310 patients with STEMI (COBALT 7169, GIK-2 2931, HERO-2 17,089, ASSENT-2 17,005, and ASSENT-3 6116 patients) from 53 countries was performed. Countries were divided into three groups according to their GNI based on the World Bank data: low (less than 2900 US dollars), medium (between 2900 US dollars and 9000 US dollars), and high GNI (more than 9000 US dollars per capita). Baseline characteristics, in-hospital management variables, and 30-day outcomes were evaluated. A previously defined logistic regression model was used to adjust for differences in baseline characteristics and to predict mortality. The observed mortality was higher than the predicted mortality in the low (12.1 vs. 11.8%) and in the medium income groups (9.4 vs. 7.9%), whereas it was lower in the high income group (4.9 vs. 5.6%). CONCLUSION: An inverse relationship between mortality and GNI was observed in STEMI clinical trials. Most of the variability in mortality can be explained by differences in baseline characteristics; however, after adjustment, lower income countries have higher mortality than the expected.