Table 3 Outcome of clonidine intervention – symptom scores and catecholamines

Symptoms scores

Orthostatic symptoms – total score

 Clonidine group, mean

3.8

3.5

 Placebo group, mean

3.5

3.5

 Difference (95 % CI)

−0.05 (−0.5 to 0.4)

 p-value (clonidine vs. placebo)

0.84

Palpitations - score

 Clonidine group, mean

2.4

2.2

 Placebo group, mean

2.2

2.2

 Difference (95 % CI)

0.06 (−0.3 to 0.4)

 p-value (clonidine vs. placebo)

0.73

Pale and cold hands - score

 Clonidine group, mean

3.0

2.7

 Placebo group, mean

3.0

2.8

 Difference (95 % CI)

−0.1 (−0.5 to 0.3)

 p-value (clonidine vs. placebo)

0.62

Catecholamines

Plasma norepinephrine - pmol/L

 Clonidine group, mean

2040

1557

 Placebo group, mean

1942

1761

 Difference (95 % CI)

−205 (−406 to −4)

 p-value (clonidine vs. placebo)

0.05

Plasma epinephrine - pmol/L

 Clonidine group, mean

327

291

 Placebo group, mean

415

299

 Difference (95 % CI)

−8 (−44 to 29)

 p-value (clonidine vs. placebo)

0.68

Urine norepinephrine/creatinine ratio - nmol/mmol

 Clonidine group, mean

13.3

9.6

 Placebo group, mean

13.7

13.6

 Difference (95 % CI)

−3.9 (−6.4 to −1.5)

 p-value (clonidine vs. placebo)

0.002

Urine epinephrine/creatinine ratio - nmol/mmol

 Clonidine group, mean

1.7

1.2

 Placebo group, mean

1.6

1.6

 Difference (95 % CI)

−0.4 (−0.8 to 0.1)

 p-value (clonidine vs. placebo)

0.11