Table 1 Demographics and clinical characteristics of RA and control subjects

Age, years, mean

55.1 (16.5)

53.2 (16.0)

0.81

Female, %

62.5%

70.0%

1.0

Race⁺, %

 Caucasian

 Non-Caucasian

  African American

  Hispanic

  Indian

  Unknown

50%

50%

25%

12.5%

12.5%

0%

30%

70%

10%

10%

0%

50%

0.63

BMI (kg/m²)

32.6

–

Diabetes mellitus

0%

–

Smoking history

 Current

12.5%

–

 Former

37.5%

–

 Never

50%

–

RA disease characteristics

 Remission, %

75%

–

–

 Autoantibody status

  RF positive, %

75%

–

–

  ACPA positive, %

75%

–

–

 ESR mm/h, mean

23.38 (17.73)

–

–

 CRP mg/L, mean

4.26 (1.64)

–

–

 RAPID3 score, mean

10.42 (5.71)

–

–

 Medication history

  DMARDs, %

100%

–

–

  Glucocorticoids, %

0%

–

–

  Biologic agents

   TNF-inhibitor, %

0%

–

–

   Other, %

0%

–

–

Number of caries, mean

3 (3.85)

4.4 (7.07)

0.62

Probing depth, mean (mm)

 Shallow sites (PD ≤ 3 mm)

2.58

2.08

0.02

 Deep sites (PD ≥ 4 mm) ^$

4.00

3.65

0.47

Global PD status

 Healthy, %

12.5%

0%

0.54

 Periodontitis stage I, %

37.5%

40%

 Periodontitis stage II, %

12.5%

40%

 Periodontitis stage III, %

37.5%

20%