Trends in Premature Mortality from Acute Myocardial Infarction in American Indians/Alaska Natives in the United States from 1999 to 2020

Abstract

Cardiovascular disease is the leading cause of mortality in American Indian and Alaska Native (AI/AN) groups. They are disproportionately found to have a higher rates of premature myocardial infarction (MI). The CDC WONDER (Centers for Disease Control and Prevention) was queried to identify premature MI deaths (female <65 years and male <55 years) occurring within the United States between 1999-2020. We investigated proportionate mortality trends related to premature MI among AI/ANs stratified by sex. Deaths attributed to AMI were identified using the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10) codes I21- I22. We compared the proportional mortality rate due to premature MI to that of non-AI/AN racial group, which comprised of all other races (Blacks, Whites, and Asian/Pacific Islander populations). In AI/ANs, we analyzed a total of 14,055 acute myocardial infarction (AMI) deaths of which 3,211 were premature MI deaths corresponding to a proportionate mortality rate of 22.8% (male 20.8%, female 26.2%). Non- AI/AN population had a lower proportionate mortality of 14.8% (male 13.7%, female 16%); p<0.01). On trend analysis, there was no significant improvement over time in the proportionate mortality of AI/ANs (19.8% in 1999 to 21.7% in 2020, p=0.09). Upon comparison of sex, proportionate mortality of premature MI in females showed a non-statistically significant increase from 21.6% in 1999 to 27.3% in 2020 [average annual percent change (AAPC) of 0.7; p=0.06)]. However, males had a statistically significant decrease in proportionate mortality of premature MI from 18.5% in 1999 to 18.2% in 2020 [AAPC of -0.8; p=0.01)]. AI/ANs have an alarmingly higher rate of proportionate mortality of premature MI compared to other races, with no improvement in the proportionate mortality rates over 20 years, despite an overall downtrend in AMI mortality. Further research to address the reasons for the lack of improvement in premature MI is needed to improve outcomes in this patient population.