Electronic health record embedded frailty index and outcomes among older adults receiving cancer chemotherapy

PURPOSE: We evaluated whether an automated electronic health record (EHR)-based frailty index (eFI) is associated with hospitalization and overall survival (OS) in older adults receiving chemotherapy. PATIENTS AND METHODS: We identified 509 consecutive patients aged ≥65 years with newly diagnosed lung, colorectal, or breast cancer treated with chemotherapy (2017-2020). An automated eFI score was calculated using data from ≥2 visits in the 2 years before chemotherapy, including vital signs, smoking status, diagnoses, selected laboratory values, and functional measures. Frailty was categorized using a cumulative deficit approach as fit (eFI ≤0.10), pre-frail (0.10-0.21), or frail (>0.21). Hospitalizations at 3 and 6 months were compared across groups. Adjusted associations between eFI and hospitalization and mortality were assessed using Cox regression models. OS was estimated by Kaplan-Meier methods and compared using log-rank tests. RESULTS: Among 509 patients (median age, 72.2 years), 27.7% were fit, 42.4% pre-frail, 14.9% frail, and 14.9% had non-calculable eFI. Six-month hospitalization increased with frailty: 24% (fit), 42% (pre-frail), 62% (frail), and 50% (non-calculable) (P<.0001). Median OS was 38 months (fit), 23 months (pre-frail), 17 months (frail), and 10 months (not calculable) (p < 0.0001). In adjusted models, mortality risk was higher in pre-frail (HR 1.7, 95% CI 1.2-2.3), frail (HR 2.0, 95% CI 1.3-3.1), and not calculable groups (HR 2.6, 95% CI 1.7-4.0) compared with fit patients. CONCLUSION: EHR-derived frailty was associated with hospitalization and survival, supporting the eFI as a scalable approach to risk stratification in older adults undergoing chemotherapy.