. Author manuscript; available in PMC: 2011 Jun 22.

Published in final edited form as: J Am Coll Cardiol. 2010 Jun 22;55(25):2858–2868. doi: 10.1016/j.jacc.2010.02.043

Table 3.

Cardiovascular and sympathetic responses during the cold pressor test

Variables	POTS Patients (n = 27)				Healthy Controls (n = 16)
Variables	Baseline	CPT-1min	CPT-2min	Recovery	Baseline	CPT-1min	CPT-2min	Recovery
SBP (mmHg)	110 [99, 118]	120^** [113, 130]	127^** [119, 137]	112 [101, 117]	114 [110, 121]	126^** [121, 133]	130^** [115, 138]	114 [110, 120]
DBP (mmHg)	66 [63, 70]	80^** [71, 88]	78^** [73, 85]	66 [63, 68]	68 [65, 72]	82^** [72, 86]	77^** [71, 83]	69 [65, 73]
HR (bpm)	79^† [69, 87]	82^*^† [72, 97]	82^† [70, 93]	72^† [66, 86]	67 [62, 72]	79^* [69, 87]	71 [63, 79]	64^* [58, 70]
MSNA-BF (bursts/min)	9 [4, 15]	22^** [16, 47]	30^** [16, 36]	16^* [6, 18]	7 [4, 13]	29^** [15, 36]	24^** [9, 38]	13^* [6, 17]
MSNA-BI (Bursts/100 heart beats)	9 [6, 18]	30^** [15, 55]	38^** [16, 44]	19^** [7, 27]	11 [6, 19]	32^** [20, 50]	35^** [14, 47]	18^* [11, 26]
Total Activity (a.u./min)	170 [99, 265]	560^** [336, 1098]	612^** [324, 876]	265 [121, 346]	123 [65, 211]	725^** [216, 935]	533^** [255, 808]	225^* [169, 325]

Values are expressed as median [25%, 75%]. CPT, the cold pressor test; SBP and DBP, systolic and diastolic blood pressure; HR, heart rate; MSNA-BF, muscle sympathetic nerve activity burst frequency; MSNA-BI, muscle sympathetic nerve activity burst incidence; a.u. arbitrary unit.

P < 0.05 and

^**

P < 0.01 vs baseline within the same group;

^†

P<0.05 vs healthy controls.