When only preoperative screening factors (ASA, AA‐CCI, CFS, G8, haemoglobin, albumin and GFR) were analysed in multivariable regression analysis, CFS ≥ 5 (2.94, 1.23–7.03, p = 0.015), albumin level < 31 g/L (1.97, 1.03–3.74, p = 0.039) and GFR < 45 mL/min (2.02, 1.07–3.82, p = 0.030) were associated with reduced OS (Supplement 3). This evidence concerns the gene ALB and myalgic encephalomeyelitis/chronic fatigue syndrome.