Table 6 Adjusted HRs and 95% CIs for time to serious infection (n = 21,832)

 Non-TNF biologic ± DMARDs

Reference

–

 DMARDs

0.80

0.62–1.03

 TNFi ± DMARDs

1.14

0.95–1.37

 Tofacitinib ± DMARDs

1.54

0.93–2.56

Current use of methotrexate^a

1.19

1.04–1.37

Previous use of biologics^a

1.32

1.12–1.57

Previous use of other DMARDs^a

1.04

0.86–1.27

Sex (female)

1.02

0.87–1.18

Age

1.04

1.03–1.04

 2011

Reference

–

 2012

1.10

0.92–1.31

 2013

0.85

0.66–1.08

 2014

0.97

0.70–1.35

 No use

Reference

–

 Use of ≤ 7.5 mg/day of prednisone equivalent dose

1.23

1.05–1.44

 Use of > 7.5 mg/day of prednisone equivalent dose

1.36

1.00–1.84

 No use

Reference

–

 Use of ≤ 7.5 mg/day of prednisone equivalent dose

1.90

1.64–2.20

 Use of > 7.5 mg/day of prednisone equivalent dose

2.83

1.37–5.83

Nonsteroidal anti-inflammatory drugs use 1 year prior to cohort entry

0.93

0.81–1.06

Selective COX-2 inhibitors use 1 year prior to cohort entry

1.13

0.95–1.35

Charlson comorbidity index 1 year prior to cohort entry

1.72

1.49–1.99

Infection related hospitalization 1 year prior to cohort entry

2.19

1.68–2.86

Number of emergency department visits 1 year prior to cohort entry

1.04

1.01–1.06

Number of physician visits 1 year prior to cohort entry

1.01

1.00–1.01

Number of rheumatology visits 1 year prior to cohort entry

1.00

0.99–1.02

Number of hospitalizations 1 year prior to cohort entry

1.33

1.24–1.43