Research Article

Risk Factors for Hospital and Long-Term Mortality of Critically Ill Elderly Patients Admitted to an Intensive Care Unit

Table 3

Univariate analysis of mortality in-hospital and following discharge.

Characteristics Hospital mortalityMortality following hospital discharge
Unadjusted SHR (95% CI) valueUnadjusted SHR (95% CI) value

Female sex0.93 (0.76–1.13)0.4621.01 (0.82–1.26)0.898
Age ≥ 65 years1.81 (1.49–2.19)<0.0011.90 (1.53–2.35)<0.001
Race0.1630.001
 Chinese1.001.00
 Malay0.90 (0.71–1.14)0.3751.05 (0.82–1.35)0.685
 Indian0.67 (0.46–0.96)0.0300.71 (0.48–1.04)0.080
 Others0.88 (0.60–1.30)0.5030.21 (0.09–0.48)<0.001
Comorbidities0.120<0.001
 0-11.001.00
 2-31.11 (0.86–1.42)0.4282.40 (1.69–3.42)<0.001
 >31.28 (1.01–1.62)0.0443.94 (2.83–5.48)<0.001
Diagnosis
 Sepsis
  Pulmonary1.11 (0.90–1.38)0.3350.76 (0.59–0.98)0.037
  Others1.20 (0.84–1.71)0.3150.46 (0.25–0.84)0.011
 Organ-specific disease
  Hepatic0.94 (0.65–1.36)0.7431.52 (1.05–2.20)0.025
  Neurological1.51 (1.06–2.13)0.0210.77 (0.48–1.25)0.289
  Renal0.56 (0.32–0.96)0.0362.32 (1.63–3.32)<0.001
  Cardiovascular0.93 (0.57–1.51)0.7681.10 (0.67–1.78)0.713
  Endocrine0.21 (0.07–0.64)0.0060.57 (0.26–1.28)0.176
  Pulmonary, airway0.55 (0.35–0.86)0.0081.74 (1.27–2.40)0.001
  Pulmonary, others*0.69 (0.33–1.43)0.3151.67 (0.96–2.93)0.072
 Malignancy<0.0010.022
  Hematological 2.18 (1.60–2.98)<0.0010.97 (0.57–1.65)0.916
  Nonhematological2.43 (1.68–3.53)<0.0011.99 (1.22–3.24)0.006
 Others0.69 (0.49–0.97)0.0330.61 (0.41–0.89)0.011
Investigations
 Hemoglobin, per g/dL0.94 (0.91–0.97)<0.0010.93 (0.90–0.96)<0.001
 Platelets, per/mm30.999 (0.998–0.9997)0.0111.001 (1.000–1.002)0.007
 White blood cells, per/mm31.003 (0.999–1.007)0.1041.001 (0.996–1.006)0.773
 BUN, per mmol/L1.006 (0.999–1.014)0.1031.010 (1.002–1.018)0.016
 Creatinine, per µmol/L0.9999 (0.9997–1.0003)0.9221.0003 (0.9999–1.0007)0.062
MPM II score, per point1.03 (1.02-1.03)<0.0011.005 (1.001–1.010)0.009
Treatment
 Mechanical ventilation4.66 (3.51–6.19)<0.0010.71 (0.57–0.88)0.002
 Noninvasive ventilation0.75 (0.61–0.91)0.0041.62 (1.31–2.01)<0.001
 Vasopressor4.04 (3.23–5.04)<0.0010.58 (0.46–0.72)<0.001
 Packed cell transfusion1.91 (1.57–2.31)<0.0010.98 (0.77–1.24)0.848
 Renal replacement therapy<0.001<0.001
  Preexisting2.78 (2.20–3.53)<0.0010.54 (0.34–0.86)0.010
  New cases1.29 (0.95–1.77)0.1071.58 (1.16–2.15)0.004
 CPR prior to admission4.00 (2.94–5.44)<0.0010.98 (0.60–1.60)0.926

SHR: subdistribution hazard ratio; BUN: blood urea nitrogen; CI: confidence interval; CPR: cardiopulmonary resuscitation; MPM: mortality prediction model; Refers specifically to obstructive sleep apnea and restrictive lung diseases.