Table 1 Demographic characteristics of matched study cohorts

Age, y, mean (SD)

53.88 (13.08)

53.89 (13.09)

0.97

Female gender, n (%)

3813 (86.20)

15252 (86.20)

1.00

Disease duration before index date, y, median (Q1, Q3)

9.21 (6.84, 11.23)

9.20 (6.81, 11.20)

0.70

Follow-up duration, y, median (Q1, Q3)

3.30 (2.00, 5.39)

3.25 (1.95, 5.29)

0.14

Outcome

  Cancer, n (%)

89 (2.00)

486 (2.70)

0.001

  Death before outcome, n (%)

192 (4.30)

933 (5.30)

<0.001

  Overall observation person-years

16650.63

65587.93

  Cancer, incidence rates (95% CI) per 1000 person-years

5.35 (4.23, 6.46)

7.41 (6.75, 8.07)

<0.005

Number of visits per year during follow ups, median (Q1, Q3)

13.33 (11.61, 14.81)

6.04 (3.15, 9.3)

<0.001

Co-morbidities, n (%)

  Hypertension

1418 (32.0)

5672 (32.0)

1.00

  Chronic liver disease

813 (18.4)

3252 (18.4)

1.00

  Ischemic heart disease

496 (11.2)

1984 (11.2)

1.00

  Diabetes

388 (8.8)

1552 (8.8)

1.00

  Cerebrovascular disease

96 (2.2)

384 (2.2)

1.00

Prior drug use, n (%)¹

  Methotrexate

4125 (93.2)

8659 (48.9)

<0.001

  Sulfasalazine

3276 (74.0)

8531 (48.2)

<0.001

  Hydroxychloroquine

3515 (79.4)

10976 (62.0)

<0.001

  Glucocorticosteroids

4003 (90.4)

12875 (72.7)

<0.001

Other systemic drugs use, n (%)²

  Statin

433 (9.8)

2069 (11.7)

<0.001

  Metformin

264 (6.0)

1096 (6.2)

0.60

  NSAID

4349 (98.3)

17041 (96.3)

<0.001

  Beta-blockers

1115 (25.2)

4337 (24.5)

0.35

Average dosage of certain DMARDs during follow up, each user, mean (SD)³

  Methotrexate

9.1(4.32)

6.25 (4.31)

<0.001

  Sulfasalazine

822.11(652.64)

720.69 (575.53)

<0.001

  Hydroxychloroquine

194.71(137.37)

187.2 (123.95)

<0.001

  Glucocorticosteroids

4.42 (3.6)

3.02 (3.21)

<0.001