Electronic frailty index predicts 30-day mortality from chemotherapy in breast, colorectal and lung cancer.
Authors: Michael Agnieszka , Huynh Jennie , Sutton Katie , Mansi Janine , Skene Simon , Ford Elizabeth , Armes Jo , Luchtenborg Margreet 
Published: June 2023

12009 Background: Older and frail patients with cancer (Ca) often receive less aggressive treatment and as a result have worse survival. Current methods of assessing fitness (performance status) for intensive treatment such as chemotherapy are inadequate. The complexity of geriatric assessments, lack of training and time pressures in busy clinics, mean that better solutions are needed. A UK initiative - the electronic frailty index (eFI) - is derived from a cumulative deficit frailty model and provides a measure of frailty alongside pre-existing conditions such as issues with mobility, fractures, falls, memory, sight, hearing , anaemia, tremor, diabetes, heart, thyroid, skin, respiratory, cerebrovascular, circulation, social vulnerability, and polypharmacy (36 fields) (Clegg et al). Patients are classified into the following groups: no frailty, mild, moderate or severe frailty. We used the same methodology to investigate whether eFI predicts adverse outcomes of chemotherapy in frail patients with Ca. Methods: The study conducted retrospective data analysis of Ca patients treated with chemotherapy from Public Health England (PHE) Systemic Chemotherapy Dataset (SACT) years 2015-2018. Eligible patients had stage II - III breast Ca, stage III colon Ca or stage IIIB–IV non-small-cell lung Ca (NSCLC). The data from SACT was linked with hospital episodes' statistics (obtained from NHS-Digital) to calculate 30-day SACT mortality, overall survival and hospital admissions. EFI was calculated from the above 35 fields; polypharmacy was not available from NHS-Digital data. Results: The eFI was calculated for 78799 patients: colorectal 17951, lung 22052, and breast 38796. 20388 patients were ≥ 70y. o. and 58411 were < 70y.o. Most patients were fit with an eFI score of 0-69% (54563), 19% (15,295) had mild frailty, 7.7% (6104)- moderate, and 3.6% (2837) had severe frailty. 4.2% (3356) of patients died within 30 days of SACT. For colorectal Ca patients the risk of dying within 30 days of SACT in patients ≥70y.o was twice that of the < 70y.o (OR 2.04 -CI 1.58 - 2.64); patients with mild eFI did not differ- OR: 1.07 (CI 0.78-1.45), moderate frailty: 1.6 (CI 1.1-2.33) and severe frailty: 2.13 (CI 1.34-3.39). In breast Ca patients, 30-day mortality for ≥70y.o. was 6.38 times higher than for < 70y.o (95% CI 4.29-9.49); eFI for mild frailty- OR of 1.45 (95% CI 0.78-2.71), moderate frailty-OR of 3.5 (95%CI 1.82-6.75) and severe frailty 5.73 (95% CI 2.66-12.3). The 30-day mortality in lung cancer in ≥70y.o and < 70y.o did not differ with OR 0.95 (95% CI 0.88-1.03) for ≥70y.o. Patients with mild frailty had OR for 30-day mortality of 1.17 (95% CI 1.07-1.28), moderate frailty-OR of 1.28 (95%CI 1.15-1.44) and severe frailty 1.48 (95% CI 1.28-1.77). Conclusions: The eFI closely predicts poor outcomes from SACT, particularly in early breast and colon cancer, and requires further evaluation in a prospective study.