INTERHEART

Trends in ST-elevation myocardial infarction hospitalization among young adults: a binational analysis

BACKGROUND

ST-segment myocardial infarction (STEMI) is typically associated with increased age, but there is an important group of patients who suffer from STEMI under the age of 50 who are not well characterized in studies.

METHODS AND RESULTS

We analysed results from Myocardial Ischemia National Audit Project (MINAP) from the United Kingdom (UK) between 2010 and 2017 and the National Inpatient Sample (NIS) from the United States of America (USA) between 2010 and 2018. After exclusion criteria, there were 32 719 STEMI patients aged ≤50 from MINAP, and 238 952 patients' ≤50 from the NIS. We analysed temporal trends in demographics, management, and mortality. The proportion of females increased, 15.6% (2010-2012) to 17.6% (2016-2017) (UK) and 22.8% (2010-2012) to 23.1% (2016-2018) (USA). The proportion of white patients decreased, from 86.7% (2010) to 79.1% (2017) (UK) and 72.1% (2010) to 67.1% (2017) (USA). Invasive coronary angiography (ICA) rates increased in UK (2010-2012: 89.0%, 2016-2017: 94.3%), while decreased in USA (2010-2012: 88.9%, 2016-2018: 86.2% (USA). After adjusting for baseline characteristics and management strategies, there was no difference in all-cause mortality in the UK in 2016-2017 compared to 2010-2012 (OR:1.21, 95% CI:0.60-2.40), but there was a decrease in the USA in 2016-2018 compared to 2010-2012 (OR: 0.84, 95% CI: 0.79-0.90).

CONCLUSION

The demographics of young STEMI patients have temporally changed in the UK and USA, with increased proportions of females and ethnic minorities. There was a significant increase in the frequency of diabetes mellitus over the respective time periods in both countries.

Mortality in ST-segment elevation myocardial infarction patients without standard modifiable risk factors: A race disaggregated analysis

Background

Individuals who present with STEMI without the standard cardiovascular risk factors (SMuRFs) of diabetes, hypercholesterolemia, hypertension, and smoking, coined SMuRF-less are not uncommon. Little is known about their outcomes as a cohort and how they differ by race.

Methods & Results

We identified 431,615 admissions with STEMI in the National Inpatient Sample (NIS) database 2015–2018, including patients with ≥ 1 SMuRF (n = 369,870) and those who were SMuRF-less (n = 234,745). SMuRF-less patients presented at a similar age (median age 63y vs 63y), were less likely to be female (33.6 % vs 34.6 %) and were almost twice as likely to present as a cardiac arrest (13.7 % vs 7.0 %), than those with ≥ 1 SMuRFs. SMuRF-less patients were less frequently in receipt of ICA (71.3 % vs 83.8 %) and PCI (58.0 % vs 72.2 %) compared to those with ≥ 1 SMuRF. Our race disaggregated analysis showed ethnic minority SMuRF-less patients were less likely than White patients to receive ICA and PCI, which was most apparent in Black patients with reduced odds of ICA (OR: 0.47, 95 % CI: 0.43–0.52) and PCI (OR: 0.46, 95 % CI: 0.52–0.50). Similarly, in ethnic minority subgroups within the SMuRF-less cohort, mortality and MACCE were significantly higher than in White patients. This was most profound in Black patients with in-hospital mortality (OR: 1.90, 95 % CI: 1.72–2.09) and MACCE (OR: 1.63, 95 % CI: 1.49–1.78) compared to White patients.

Conclusion

Ethnic Minority SMuRF-less patients were less likely than White SMuRF-less patients to receive ICA and PCI and had worse mortality outcomes.

Addressing disparities of care in non-ST-segment elevation myocardial infarction patients without standard modifiable risk factors: insights from a nationwide cohort study

AIMS

The importance of standard modifiable cardiovascular risk factors (SMuRFs) in preventing non-ST-segment elevation myocardial infarction (NSTEMI) is established. However, NSTEMI may present in the absence of SMuRFs, and little is known about their outcomes.

METHODS AND RESULTS

We analysed 176 083 adult (≥18 years) hospitalizations with NSTEMI using data from the United Kingdom (UK) Myocardial Infarction National Audit Project (MINAP). Clinical characteristics and all-cause in-hospital mortality were analysed according to SMuRF status, with 135 223 patients presenting with at least one of diabetes, hypertension, hypercholesterolaemia, or current smoking status and 40 860 patients without any SMuRFs. Those with a history of coronary artery disease were excluded. Patients without SMuRFs were more frequently older (median age 72 year vs. 71 years, P < 0.001), male (62% vs. 61%, P < 0.001), and Caucasian (95% vs. 92%, P < 0.001). Those without SMuRFs less frequently received statins (71% vs. 81%, P < 0.001), had their left ventricular (LV) function recorded (62% vs. 65%, P < 0.001) or for those with moderate or severe LV systolic dysfunction were prescribed angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (80% vs. 85%, P < 0.001). Following propensity score matching the odds of all-cause mortality [odds ratio (OR): 0.85, 95% confidence interval (CI): 0.77-0.93], cardiac mortality (OR: 0.85, 95% CI: 0.76-0.94), and major adverse cardiovascular events (MACE) (OR: 0.85, 95% CI: 0.77-0.93) were lower in patients without SMuRFs.

CONCLUSION

More than one in five patients presenting with NSTEMI had no SMuRFs, who were less frequently received guideline-recommended management and had lower in-hospital (all-cause and cardiac) mortality and MACE than patients with SMuRFs.

Explaining the social gradient in coronary heart disease: comparing relative and absolute risk approaches

STUDY OBJECTIVES

There are contradictory perspectives on the importance of conventional coronary heart disease (CHD) risk factors in explaining population levels and social gradients in CHD. This study examined the contribution of conventional CHD risk factors (smoking, hypertension, dyslipidaemia, and diabetes) to explaining population levels and to absolute and relative social inequalities in CHD. This was investigated in an entire population and by creating a low risk sub-population with no smoking, dyslipidaemia, diabetes, and hypertension to simulate what would happen to relative and social inequalities in CHD if conventional risk factors were removed.

DESIGN, SETTING, AND PARTICIPANTS

Population based study of 2682 eastern Finnish men aged 42, 48, 54, 60 at baseline with 10.5 years average follow up of fatal (ICD9 codes 410-414) and non-fatal (MONICA criteria) CHD events.

MAIN RESULTS

In the whole population, 94.6% of events occurred among men exposed to at least one conventional risk factor, with a PAR of 68%. Adjustment for conventional risk factors reduced relative social inequality by 24%. However, in a low risk population free from conventional risk factors, absolute social inequality reduced by 72%.

CONCLUSIONS

Conventional risk factors explain the majority of absolute social inequality in CHD because conventional risk factors explain the vast majority of CHD cases in the population. However, the role of conventional risk factors in explaining relative social inequality was modest. This apparent paradox may arise in populations where inequalities in conventional risk factors between social groups are low, relative to the high levels of conventional risk factors within every social group. If the concern is to reduce the overall population health burden of CHD and the disproportionate population health burden associated with the social inequalities in CHD, then reducing conventional risk factors will do the job.