Table 4 Results of multiple linear regression models between comorbidities and TMD pain duration in participants in the m-TMD group (n = 121)

TMD duration (years)

Number of comorbidity

1.51 (0.35 – 2.66)

1.53 (0.33 – 2.73)

1.44 (0.25 – 2.62),

p < 0.05, r² = 0.05

p < 0.05, r² = 0.07

p < 0.05, r² = 0.11

Migraine

1.11 (−1.72 – 3.94)

0.34 (−2.60 – 3.28)

−0.01 (−2.89 –2.87)

p = 0.44, r² = 0.01

p = 0.82, r² = 0.18

p = 0.99, r² = 0.17

Chronic Fatigue Syndrome

5.38 (1.91 – 8.84),

5.98 (2.16 – 9.79),

5.54 (1.78 – 9.30),

p < 0.01, r = 0.07

p < 0.01, r² = 0.18

p < 0.01, r² = 0.17

Irritable Bowel Syndrome

3.08 (0.06 – 6.09)

3.14 (0.04 – 6.25)

3.14 (0.04 – 6.23)

p = 0.05, r² = 0.03

p = 0.05, r² = 0.18

p = 0.05, r² = 0.17

Interstitial Cystitis

2.04 (−2.01 – 6.09)

−0.88 (5.17 – 3.42)

−0.71 (−4.98 – 3.56)

p = 0.32, r² = 0.01

p = 0.69, r² = 0.18

p = 0.74, r² = 0.17

Restless Leg Syndrome

−0.23 (−4.03 – 3.56)

−1.74 (−5.54 – 2.07)

−1.69 (−5.47 – 2.09)

p = 0.90, r² = 0.001

p = 0.37, r² = 0.18

p = 0.38, r² = 0.17