The results showed that age, dyslipidaemia, respiratory failure, duration of intubation, SBP, DPB, heart rate, FiO2, lactate, sodium, calcium, ALB, ALT, AST, eGFR, DD, CSA, SMI, standardized SMI, SMI subgroups (grouped by median), SMI subgroup (grouped by cut-off point) and mean intermuscular fat density were significantly associated with all-cause mortality (p < 0.05). Here, ALB is linked to respiratory failure.