Table 5

Cox proportional hazards models evaluating development of cerebral oedema

ModelHazard Ratio95% CIp
Effective osmolality0.97(0.95 to 0.99)0.01
Glucose1.01(0.97 to 1.05)0.57
Sodium0.90(0.85 to 0.96)0.001
Glucose-corrected sodium0.92(0.88 to 0.97)0.004
pH0.92(0.88 to 0.96)<0.001
Base excess0.79(0.70 to 0.89)<0.001
Anion gap1.12(1.05 to 1.19)<0.001
  • HRs are expressed per mmol/l unit change in the independent variable, apart from pH which is expressed per 0.01 pH units.

  • All models were adjusted for blood urea and partial pressure of carbon dioxide at presentation. All variables shown above were entered as time varying covariates.