Table 3.

Changes in ANS, BP, and mHR Responses from Predosing (Test N) to Postdosing (Test N + 1), including Sympathetics (S), Parasympathetics (P), SB, Systolic BP (sBP), and Diastolic BP (dBP)^a

	ΔΔS	ΔΔP	ΔΔSB	ΔΔmHR	ΔΔsBP	ΔΔdBP
Midodrine (− +)	1.42**	−0.81	0.77	−0.24	2.63**	1.53*
Midodrine (+ −)	−0.16*	−0.13	0.04*	0.05	−6.41*	−2.84*
Midodrine (+ +)	0.43	−1.86*	0.49	−1.11	1.64*	0.02

^aThe “ΔΔ” symbol indicates that a change in the response is represented. For example, an abnormal stand response in a single test is a decrease in sympathetic activity as compared to the resting seated position. This response may then change and become normalized as an increase in sympathetic activity upon standing. As a result, the change in the response (ΔΔ) would be positive. Changes marked with an asterisk are significant (*P < 0.01 or **P < 0.001). See text for details.