Table 2 Effect of COMT haplotypes on symptoms at the Chronic Fatigue Syndrome symptom list (CSL), pain thresholds, and conditioned pain modulation in both healthy controls (HC) and patients with Chronic Fatigue Syndrome and Fibromyalgia (CFS/FM). Data is expressed as estimated adjusted mean (standard error). Mean difference and p-values refer to the difference between the first and the last category. CPT: cold pain thresholds; HPT: heat pain thresholds; C-CPM: conditioned pain modulation to cold stimuli; H-CPM: conditioned pain modulation to heat stimuli

COMT

High

activity

COMT

High-intermediate

activity

COMT

Intermediate

activity

COMT intermediate-low

activity

COMT

High

activity

COMT

High-intermediate

activity

COMT

Intermediate

activity

COMT intermediate-low

activity

Mean diff.

(95% C.I.)

p

CSL Total

18.78

(8.85)

22.54

(5.55)

28.86

(8.59)

63.55

(13.02)

91.83

(10.73)

95.59

(5.08)

101.91

(8.93)

136.60

(11.95)

-44.771

(-87.89; -1.65)

0.014*

CPT (°C)

2.10

(1.51)

5.24

(1.15)

4.49

(1.42)

11.36

(2.15)

5.47 (1.61)

8.61

(0.95)

7.83

(1.48)

14.74

(2.38)

-9.263 (-16.197; -2.33)

0.006*

HPT (°C)

47.55

(0.95)

47.19

(0.72)

47.73

(0.89)

46.45

(1.35)

45.80 (1.01)

45.44

(0.60)

45.97

(94)

44.69

(1.50)

1.108 (-3.26; 5.47)

0.825

 C-CPM (°C)

2.19

(0.56)

2.43

(0.41)

2.05

(0.50)

4.99

(0.77)

1.97

(0.57)

2.22

(0.34)

1.84

(0.52)

4.78

(3.02)

-2.804 (-5.39; − 0.21)

0.011*

H-CPM (°C)

1.23

(0.40)

1.14

(0.30)

1.17

(0.37)

2.10

(0.56)

0.89

(0.42)

0.81

(0.25)

0.84

(0.37)

1.76

(0.62)

− 0.872 (-2.68; 0.93)

0.418