Table 1 Baseline characteristics of early rheumatoid arthritis patients

Age (years)

52.7 ± 13.6

47.5 ± 15.1

53.0 ± 13.4

< 0.01

Female sex

9525 (76.8)

456 (63.9)

9069 (77.6)

< 0.01

Insurance type

< 0.01

 Health insurance

11,661 (94.1)

682 (95.5)

10,979 (94.0)

 Medicaid

736 (5.9)

32 (4.8)

704 (6.0)

Type of institution

< 0.01

 Tertiary hospital

2646 (21.3)

231 (32.4)

2415 (20.7)

 General hospital

2430 (19.6)

161 (22.6)

2269 (19.4)

 Community hospitals/clinics/other

7321 (59.1)

322 (45.1)

6999 (59.9)

Department

< 0.01

 Internal medicine

5064 (40.9)

362 (50.7)

4702 (40.3)

 Orthopedic surgery

5839 (47.1)

265 (37.1)

5574 (47.7)

 Other

1494 (12.1)

87 (12.2)

1407 (12.0)

Number of comorbidities

0.84 ± 1.01

0.80 ± 0.93

0.85 ± 1.01

0.17

 0

5755 (46.4)

338 (47.3)

5417 (46.4)

 1

3993 (32.2)

231 (32.4)

3762 (32.2)

0.76

  ≥ 2

2649 (21.4)

145 (20.3)

2504 (21.4)

CCI score

2.0 ± 1.2

1.9 ± 1.1

2.0 ± 1.2

0.14

Methotrexate use

5283 (42.6)

437 (61.2)

4846 (41.5)

< 0.01

Methotrexate dose (mg/week)

9.8 ± 3.0

10.9 ± 3.1

9.7 ± 3.0

< 0.01

 Dosage = 0

7114 (57.5)

277 (38.8)

6837 (58.6)

 0 < dosage < 10

2452 (19.8)

147 (20.6)

2305 (19.8)

< 0.01

 Dosage ≥ 10

2814 (22.7)

290 (40.6)

2524 (21.6)

Hydroxychloroquine

7016 (56.6)

339 (47.5)

6677 (57.2)

< 0.01

Sulfasalazine

2704 (21.8)

296 (41.5)

2408 (20.6)

< 0.01

Bucillamine

737 (5.9)

31 (4.3)

706 (6.0)

0.07

Leflunomide

687 (5.5)

84 (11.8)

603 (5.2)

< 0.01

Tacrolimus

87 (0.7)

13 (1.8)

74 (0.63)

< 0.01

Oral corticosteroid use

8851 (71.4)

549 (76.9)

8302 (71.1)

< 0.01

Corticosteroid dose (mg/day)

7.4 ± 4.8

7.8 ± 4.1

7.4 ± 4.8

0.04

 Dosage = 0

3546 (33.3)

165 (26.0)

3381 (33.7)

 0 < dosage < 5

1244 (11.7)

39 (6.1)

1205 (12.0)

< 0.01

 Dosage ≥ 5

5874 (55.1)

431 (67.9)

5443 (54.3)

NSAID use

11,366 (91.7)

671 (94.0)

10,695 (91.5)

0.03