Table 4 Detailed analysis of factors associated with outcome in the treatment periods before and after 15 days after ICU admission. This landmark analysis allows differentiation of factors that are relevant for outcome earlier and later during the disease course

(A) Analysis of overall survival probability before day 15 (N = 2625 patients)

Surge

Second versus first

1.04 (95% CI 0.83–1.3)

0.7293

Frailty (ref = Fit)

Vulnerable (CFS 4)

1.27 (95% CI 0.97–1.68)

0.0863

Frail (CFS 5–8)

2.03 (95% CI 1.6–2.58)

 < 0.0001

Age

One year increase

1.07 (95% CI 1.05–1.09)

 < 0.0001

Habitat (ref = own home)

Other home with family or caregivers

1.36 (95% CI 1–1.84)

0.0506

Nursing home

0.68 (95% CI 0.36–1.28)

0.2343

Hospital ward

0.94 (95% CI 0.57–1.53)

0.7914

Other/unknown

0.71 (95% CI 0.44–1.15)

0.1635

Sex

Female versus male

0.96 (95% CI 0.8–1.14)

0.6154

PaO₂/FiO₂ ratio

One point increase

1 (95% CI 1–1)

0.1628

Sofa_neuro

One point increase

1.15 (95% CI 1.06–1.25)

0.0009

Sofa_cardio

One point increase

1.01 (95% CI 0.95–1.07)

0.6976

Sofa_liver

One point increase

1.09 (95% CI 0.92–1.31)

0.3166

Sofa_coag

One point increase

1.17 (95% CI 1–1.37)

0.0499

Sofa_kidney

One point increase

1.31 (95% CI 1.19–1.43)

 < 0.0001

BMI

One point increase

1.01 (95% CI 0.99–1.03)

0.2848

Diabetes (any type)

Yes versus no

1.13 (95% CI 0.93–1.39)

0.2196

Ischemic heart disease

Yes versus no

1.14 (95% CI 0.91–1.42)

0.2495

Renal insufficiency

Yes versus no

0.95 (95% CI 0.73–1.23)

0.6927

Arterial hypertension

Yes versus no

0.88 (95% CI 0.75–1.02)

0.0954

Pulmonary comorbidity

Yes versus no

1.07 (95% CI 0.9–1.28)

0.4122

Chronic heart failure

Yes versus no

1.1 (95% CI 0.84–1.43)

0.5031

(B) Landmark analysis of overall survival probability after day 15 (patients alive 15 days after ICU admission and with follow-up > 15 days—N = 1790)

Surge

Second versus first

1.87 (95% CI 1.44–2.43)

 < 0.0001

Frailty (ref = Fit)

Vulnerable (CFS 4)

1.24 (95% CI 0.91–1.69)

0.1661

Frail (CFS 5–8)

1.53 (95% CI 1.11–2.11)

0.0088

Age

one year increase

1.04 (95% CI 1.02–1.06)

0.0008

Habitat (ref = own home)

Other home with family or caregivers

1.23 (95% CI 0.83–1.83)

0.3048

Nursing home

0.43 (95% CI 0.17–1.09)

0.0738

Hospital ward

0.98 (95% CI 0.7–1.37)

0.9088

Other/unknown

0.86 (95% CI 0.55–1.32)

0.4847

Sex

Female versus male

0.75 (95% CI 0.6–0.93)

0.0088

PaO₂/FiO₂ ratio

One point increase

1 (95% CI 1–1)

0.3833

Sofa_neuro

One point increase

1.2 (95% CI 1.08–1.34)

0.0007

Sofa_cardio

One point increase

1.06 (95% CI 1–1.13)

0.0562

Sofa_liver

One point increase

0.94 (95% CI 0.77–1.14)

0.5151

Sofa_coag

One point increase

1.14 (95% CI 0.96–1.34)

0.1257

Sofa_kidney

One point increase

1.1 (95% CI 0.98–1.23)

0.1251

BMI

One point increase

0.99 (95% CI 0.97–1.02)

0.5460

Diabetes (any type)

Yes versus no

1.09 (95% CI 0.9–1.33)

0.3719

Ischemic heart disease

Yes versus no

0.77 (95% CI 0.57–1.05)

0.0956

Renal insufficiency

Yes versus no

1.39 (95% CI 1.02–1.9)

0.0366

Arterial hypertension

Yes versus no

0.92 (95% CI 0.77–1.09)

0.3095

Pulmonary comorbidity

Yes versus no

1.07 (95% CI 0.89–1.28)

0.4579

Chronic heart failure

Yes versus no

0.87 (95% CI 0.65–1.18)

0.3786