Table 3

Fixed and time-varyinga patient characteristics associated with vaccination

All subjects

Subjects aged 60 years or olderb

Baseline

Hazard ratio

95% Confidence interval

Hazard ratio

95% Confidence interval


Age groups, years

50-59

0.06

0.05-0.08

NA

NA

60-64c

1.00

-

-

-

≥ 65

0.41

0.31-0.53

0.42

0.33-0.54

Women, n (%)

1.13

0.95-1.35

1.17

0.97-1.41

Disease status

Rheumatoid arthritisd

1.00

-

-

-

Psoriatic arthritis

1.58

0.86-2.91

1.27

0.63-2.59

Psoriasis

1.48

1.17-1.86

1.54

1.21-1.95

Inflammatory bowel diseases

1.71

1.36-2.14

1.64

1.29-2.09

Ankylosing spondylitis

1.45

0.71-2.97

1.23

0.54-2.79

Multiple diseases

1.00

0.72-1.39

1.01

0.71-1.43

History of herpes zoster infection

Nonee

1.00

-

-

-

Recent

2.84

1.34-6.01

2.21

0.91-5.35

Remote

0.93

0.51-1.69

0.82

0.42-1.59

Medications (current use)

TNF antagonists

0.47

0.33-0.67

0.41

0.27-0.61

Other biologics (see Additional file 1)

0.52

0.19-1.40

0.59

0.22-1.58

Conventional DMARDs

0.92

0.72-1.19

0.91

0.70-1.19

Oral glucocorticoids

Nonef

1.00

-

-

-

Low/medium

0.84

0.66-1.08

0.85

0.66-1.10

High

0.46

0.15-1.45

0.53

0.17-1.68

Charlson co-morbidity index

0g

1.00

-

-

-

1

0.76

0.61-0.95

0.77

0.61-0.97

≥ 2

0.57

0.42-0.78

0.57

0.42-0.79

One or more inpatient physician visit

0.53

0.40-0.72

0.50

0.37-0.69

Number of outpatient physician visits

0-2h

1.00

-

-

-

3-5

1.68

1.32-2.14

1.70

1.31-2.19

6-10

1.80

1.39-2.34

1.80

1.37-2.38

> 10

2.08

1.47-2.93

2.03

1.41-2.92

Influenza vaccine in the past year

2.25

1.87-2.71

2.05

1.69-2.49

Pneumococcal vaccine in the past year

1.79

1.45-2.21

1.81

1.45-2.26


aGender and disease status were fixed; all other characteristics were time-varying. Time-varying characteristics were ascertained by using claims in the preceding 6-month period, unless otherwise specified in the table. bSensitivity analysis restricted to individuals aged 60 and older.

Reference groups were as follows: cage category 60-64; dRA patients; eSubjects without prior zoster infection; fsubjects not prescribed oral glucocorticoids in the past 6 months (cumulative average daily prednisone-equivalent glucocorticoid dose: low/medium ≤20 mg/day and high (> 20 mg/day); gsubjects with Charlson score = 0; hsubject who had none to two outpatient physician encounter (s) in the past 6 months. DMARDS, disease-modifying antirheumatic drugs; RA, rheumatoid arthritis; TNF, tumor necrosis factor. Bolded data indicates statistically significant associations.

Zhang et al. Arthritis Research & Therapy 2011 13:R174   doi:10.1186/ar3497

Open Data