Type 2 MI, myocardial injury common in older adults presenting to ED

Older adults aged ≥65 years accounted for nearly 60 percent of emergency department (ED) attendances by patients with suspected acute coronary syndrome (ACS) and more had type 2 myocardial infarction (MI) and myocardial injury diagnoses than younger patients, a study has shown.

In addition, the relative mortality impact of high-sensitivity troponin T (HsTnT) levels is lower among older patients regardless of adjudicated diagnoses.

The authors prospectively identified and followed patients presenting to the ED with potential ACS who underwent HsTnT testing. Diagnoses were adjudicated using the Fourth Universal Definition of MI as follows: type 1 MI, type 2 MI, acute myocardial injury, chronic myocardial injury, and other diagnoses. Age was also categorized: younger (<65 years), elderly (65–79 years), and very elderly (≥80 years).

A total of 2,738 patients had HsTnT measurements, of whom 1,611 were suitable for adjudication (42 percent aged ≤65 years). Those aged ≥65 years were more likely to have diagnoses of type 2 MI and chronic myocardial injury, while younger patients had more type 1 MI diagnoses.

At a median of 41 months (interquartile range, 10–57), the rates of late mortality were 44 percent (223/506) in patients aged ≥80 years, 22 percent (92/423) in those aged 65–79 years, and 7 percent (46/506) in those aged ≤65 years, independent of adjudicated diagnoses (log-rank p≤0.001).

Multivariable analyses revealed that the adjusted mortality hazard ratios for increasing HsTnT levels irrespective of diagnoses were lower in patients aged ≥80 years than in younger ones.