Hypercholesterolemia: diagnosed and/or treated hypercholesterolemia by a physician or abnormal lipid values (total cholesterol >200 mg/dl, low-density lipoprotein ≥130 mg/dl, high-density lipoprotein <40 mg/dl, or triglycerides >150mg/dl).
Hypertension: history of hypertension diagnosed and treated with medication, diet and/or exercise, blood pressure >140 mmHg systolic or 90 mmHg diastolic on at least two occasions, or on antihypertensive pharmacologic therapy at enrolment.
Peripheral vascular disease: claudication either with exertion or at rest, history of amputation due to arterial vascular insufficiency, endovascular or surgical revascularizations to the lower extremities, documented aortic aneurysm, or an abnormal vascular perfusion test result.
Prior AMI: history of an AMI >7 days prior to the index admission.
Prior percutaneous coronary intervention: any prior percutaneous coronary intervention performed prior to the index admission.
Prior coronary artery bypass surgery [CABG]: any CABG surgery performed prior to the index admission.
Prior stroke: any stroke documented prior to the index admission.
Chronic kidney disease: any reference to chronic kidney disease in the medical history of the patient prior to the index admission.
Chronic lung disease: documented history of chronic lung disease, including conditions like chronic obstructive pulmonary disease, asthma, or chronic bronchitis.
Chronic heart failure: history of dyspnea, fluid retention, or low cardiac output secondary to cardiac dysfunction; or rales, jugular venous distention, or pulmonary edema prior to the current admission.
Recent smoking: documented if patients had smoked within 30 days prior to enrolment.
Obesity: body mass index ≥ 30.
Killip class: documented at the time of arrival in the patient’s medical chart as follows:
Class I: Absence of rales over the lung fields and absence of S3
Class II: Rales over 50 % or less of the lung fields, or presence of an S3
Class III: Rales over more than 50% of the lung fields.
Class IV: Shock/frank pulmonary edema
Information on AMI characteristics and severity (ST elevation vs. non-ST elevation AMI, left ventricular ejection fraction <40%): obtained from the final diagnosis documented by the attending physician in the discharge form as abstracted from the medical records.
Information on the absence/presence of chest pain in the prehospital setting was obtained from the interviewa and time of day during hospital presentation (weekday, weeknight vs. weekend admission) were obtained from patients’ medical records (e.g., Emergency Department notes, physician’s notes, admission database) and pertain to the hospital at which the patient first presented.
Family history of coronary artery diseasea: documented if patients reported to have any first-degree blood relatives with a prior AMI, percutaneous coronary intervention, or CABG.
