Frailty in the Cardiac Surgical Patient: Comparison of Frailty Tools and Associated Outcomes

Abstract

Frailty measurement in cardiac surgery is poorly studied. The study purposes were to identify a simple but accurate frailty tool by comparing the simplified frailty index, Study of Osteoporotic Fractures (SOF), to a more complex frailty index, the Cardiovascular Health Study (CHS), and outcomes of frail patients to nonfrail patients. Patients aged 65 years or older admitted for elective coronary artery bypass grafting (CABG), valvular surgery (valve), or a combination of CABG/valve were recruited and administered the SOF and CHS indexes. Surgical outcomes were defined by The Society of Thoracic Surgeons. A hand-held dynamometer assessed grip strength. Health-related quality of life was assessed by the 12-Item Short Form Health Survey. Patients (n= 167) were primarily male (75%), white (88%), and CABG (23%), valve (50%), or CABG/valve (25%). Frailty agreement between the CHS (frail, n= 47) and SOF (frail, n= 15) was poor (κ= 0.185). SOF frail patients had poorer health, were men (67% vs 61%), had a decreased ejection fraction (0.467 vs 0.537), an increased Society of Thoracic Surgeons Risk (5.0 vs 3.5), and increased European System for Cardiac Operative Risk Evaluation score (8.2 vs 5.2). All SOF frail patients reported lack of energy vs 8.7% CHS frail patients, and 80% vs 23.9% reported an unintentional weight loss of 5% or more. SOF frail patients were significantly more likely to experience prolonged ventilation (20% vs 6.5%), pneumonia (20% vs 6.5%), prolonged intensive care unit hours (158.6 vs 85.01), and readmission within 30 days (20% vs 8.7%). All frail patients reported a significantly lower physical health-related quality of life. The SOF tool better identified patients considered "frail." Frail patients had more adverse outcomes and poorer health-related quality of life.