Table 1. Results for controls, neuropathic and non-neuropathic POTS subjects.

	Control (10)	Non-Neuropathic POTS (15)	Neuropathic POTS (9)
Age (years)	28±7	29±8	34±10
Height (cm)	169±7	166±5	166±13
Weight (kg)	73±14	64±6*	75±14†
Body Mass Index	25.4±3.9	23.2±2.7	27.4±4.0†
Gender	3 M	0 M	2 M
POTS Duration (years)	N/A	4.9±4.4	4.4±3.5
IENFD distal leg (fibers/mm)	14.1±5.5	13.3±3.8	5.1±0.9*†
IENFD distal thigh (fibers/mm)	16.3±5.9	16.8±4.1	8.2±1.1*†
Cold detection (°C)	29.6±1.6	28.6±2.5	29.5±1.2
Heat detection (°C)	36.1±2.81	35.3±2.8	37.9±2.4*†
Heat-pain detection (°C)	45.2±3.3	43.5±4.0	48.3±1.0*†
QDIRT number foot	63±26	54±25	49±32
QDIRT area foot	65±29	48±21	47±32
QDIRT number thigh	39±23	19±10*	30±22†
QDIRT area thigh	41±22	16±8.5*	29±25†
Exp. to Insp ratio	1.49±0.23	1.50±0.16	1.35±0.12
Max-Min heart rate (beats/min)	23.7±11.5	28.3±7.4	19.8±5.4†
Resting heart rate (beats/min)	59±7	71±9*	66±13
Tilt heart rate (beats/min)	89±13	124±10*	114±7†*
Supine SBP	122±15	119±11	121±10
Tilt SBP	118±13	123±13	118±11
Valsalva ratio	1.75±0.19	2.31±0.45*	1.83±0.34†
Valsalva baseline SBP (mmHg)	119±16	121±14	120±13
Valsalva phase 2 early blood pressure (mmHg)	107±13	108±15	108±10
Valsalva phase 2 late blood pressure (mmHg)	121±18	120±26	124±27
Valsalva phase 4 blood pressure (mmHg)	147±18	168±27	132±17*†

Differences between groups measured by ANOVA with Tamhanes T2 post-hoc test (except gender, Fishers exact test). *= P<0.05 vs. Control. †= P<0.05 neuropathic vs. non-neuropathic. SBP: systolic blood pressure. Exp. to Insp ratio- the expiratory to inspiratory ratio during deep breathing.