Background:

The World Health Organization (WHO) defines an Older Adult (OA) as any individual aged 60 or older. It is known that mortality due to acute myocardial infarction (AMI) increases with age, but age thresholds higher than those proposed by the WHO have been consistently used; therefore, describing the characteristics and in-hospital progress of this subgroup of patients, in accordance with the WHO definition, becomes relevant.

Objectives:

1) To know the prevalence of OA with acute ST-elevation myocardial infarction (STEMI) in Argentina according to the WHO, and 2) to compare their characteristics, reperfusion treatments, and mortality against those in young adults.

Methods:

Patients included in the National Registry of ST- Elevation Myocardial Infarction (Registro Nacional de Infarto con Elevación del ST, ARGEN-IAM-ST) were analyzed. Clinical features, therapies, and progress were compared in OA versus young adults.

Results:

A total of 6676 patients were enrolled, 3626 of which (54.3%) were OA. OA were mostly female (37.6% vs 31.4%, p <0.001), had hypertension (67.8% vs 47%, p <0.001), diabetes (26.1% vs 19.9%, p <0.001), dyslipidemia (45.4% vs 37%, p <0.001), and a longer coronary artery disease history (16% vs 10.3%, p < 0.001). The time to consultation in OA was longer (120 min vs 105 min, p <0.001), with a similar total ischemic time (314 min vs 310 min, p = 0.33). They received less reperfu- sion treatment (89.9% vs 88.6%, p = 0.04) and more primary angioplasty (91% vs 87.4%, p <0.001). Heart failure was more common in OAs (27.3% vs 18.5%, p <0.001), with a similar bleeding incidence (3.7% vs 3.1%, p = 0.33), and significantly higher mortality (11.4% vs 5.5%, p<0.001). Being an OA was an independent mortality predictor.

Conclusions:

More than half the cases of AMI in our country occur in OA. Older patients are less likely to receive reperfusion, more likely to have heart failure, and show twice the rate of mortality as compared to patients under 60.