Table 6 Results of multiple linear regression models between comorbidities and TMD pain duration in participants in the j-TMD group (n = 59)

TMD duration (years)

Number of comorbidity

2.77 (0.80 – 4.73),

2.54 (0.31 – 4.77),

2.38 (0.33 – 4.44),

p < 0.01, r² = 0.12

p < 0.05, r² = 0.21

p < 0.05, r² = 0.20

Migraine

2.43 (−2.59 – 7.46)

0.05 (−5.83 – 5.93)

0.39 (−5.40 – 6.17)

p = 0.34, r² = 0.02

p = 0.99, r² = 0.26

p = 0.89, r² = 0.25

Chronic Fatigue Syndrome

14.90 (5.23 – 24.55)

8.20 (−4.20 – 20.60),

9.89 (−1.71 – 21.48),

p < 0.05, r² = 0.14

p = 0.19, r² = 0.26

p = 0.09, r² = 0.25

Irritable Bowel Syndrome

2.80 (−2.53 – 8.14)

0.69 (−5.36 – 6.74)

0.69 (4.96 – 6.34)

p = 0.30, r² = 0.02

p = 0.82, r² = 0.26

p = 0.81, r² = 0.25

Interstitial Cystitis

10.20 (2.43 – 17.98)

5.58 (−4.99 –16.14)

3.64 (−6.05 – 13.33)

p = 0.01, r² = 0.11

p = 0.29, r² = 0.26

p = 0.45, r² = 0.25

Restless Leg Syndrome

5.52 (−0.40 – 11.45)

2.86 (−3.99 – 9.70)

2.30 (−4.20 – 8.81)

p = 0.07, r² = 0.06

p = 0.41, r² = 0.26

p = 0.48, r² = 0.25