Table 4.

Potential Mediation Effects of Delirium on Death After Adjustment for All Adverse Hospital Exposure Categories.

Risk Factor	HR (95% CI)	Percent Change in Parameter Estimate of Delirium
Bivariable model
Delirium	4.2 (2.8–6.3)	--
Multivariable model
Delirium	3.6 (2.3–5.5)	10.9%
Restraining devices	1.1 (0.8–1.6)
Hospital-acquired conditions	1.2 (0.8–1.9)
Other noxious insults	2.2 (1.5–3.2)

Data are based on results of inverse-probability weighted Cox regression models. Hazard ratios for death within 90 days of admission are shown for delirium only and for delirium plus all adverse hospital exposure categories. The final column shows the percentage change in parameter estimate of delirium on death with the addition all adverse hospital exposure categories to the Cox regression model. A change in the parameter estimate of delirium of more than 5% provides evidence for mediation. HR=hazard ratio; CI=confidence interval.