Prognostic Value of Functional-Nutritional Status in Older Adults With Acute Coronary Syndrome

This study aims to find out whether reduced everyday functioning before the acute illness and malnutrition help predict health outcomes in adults aged 65 years and older hospitalized with acute coronary syndrome (heart attack or unstable angina). About 270 patients (no more than 330) will be enrolled in two hospitals in Samara, Russia. After their condition has stabilized, and within seven days of admission, researchers will ask patients (or a caregiver) about their everyday functioning before the illness. They will also measure weight, height and calf circumference, ask about recent weight loss and food intake, and use a short questionnaire to screen for risk of malnutrition. With separate consent, two extra tubes of blood (11 mL in total) will be taken during a routine hospital blood draw, without an additional needle stick, so that albumin and C-reactive protein can be measured later. Information about the illness and its treatment will be collected from medical records. Participants will be followed for one year for death, heart attack, ischemic stroke and unplanned hospitalization for heart or vascular conditions. Their ability to perform everyday activities will be assessed again between days 366 and 395 after enrollment. This is an observational study: participation does not change the medical treatment patients receive.

Inclusion Criteria: * Age 65 years or older at hospital admission. * Hospitalization for acute coronary syndrome (ST-elevation myocardial infarction, non-ST-elevation myocardial infarction, or unstable angina) at one of the two participating centers, diagnosed according to applicable clinical guidelines; myocardial infarction must meet the Fourth Universal Definition criteria for type 1 myocardial infarction. * Ability to undergo the baseline functional and nutritional assessment during hospitalization (interview of the patient or caregiver and attempted measurements according to the protocol). Inability to obtain an individual measurement (for example, height, previous body weight or calf circumference) or to complete the Short Physical Performance Battery does not preclude enrollment. * Written informed consent to participate in the study. Exclusion Criteria: * Type 2-5 myocardial infarction, myocardial infarction with non-obstructive coronary arteries (MINOCA), myocarditis, or takotsubo cardiomyopathy. * Inability to provide informed consent or respond to assessment questions because of cognitive impairment, severe psychiatric illness, impaired consciousness, or another limiting condition. * Acute cerebrovascular event with severe neurological deficit. * Terminal illness or expected survival of less than one month due to cancer or another incurable condition. * Previous enrollment in the study (repeat hospitalization of an already enrolled participant). Patients with cognitive impairment may be included if they retain the ability to understand the study information, provide informed consent, and respond to assessment questions; information about pre-event functional status may be supplemented by a caregiver.