Table 5. Odds ratio for indication for ICU admission within seven days after hospital admission.

	Logistic regression				Logistic regression
	Unadjusted	Model 1	Model 2		Unadjusted	Model 1	Model 2
SDNN				RMSSD
≤ 8	reference	reference	reference	≤ 8	reference	reference	reference
> 8	0.60 (0.36–1.01)	0.59 (0.35–0.99)	0.59 (0.35–0.99)	> 8	0.60 (0.35–1.02)	0.56 (0.32–097)	0.53 (0.30–0.93)

Model 1 adjusted for age.

Model 2 adjusted for age and cardiac disease.

Note: ICU = intensive care unit, SDNN = standard deviation of normal to normal heartbeat intervals, RMSSD = root mean square of successive differences between adjacent heartbeats. Both SDNN and RMSSD cut-offs are in msec.