Table 3.

The association of infections with incident giant cell arteritis

Exposure	Unadjusted IRR (95% CI)	p Value	Adjusted IRR (95% CI)*	p Value
Herpes zoster infection	1.24 (1.10 to 1.39)	<0.01	1.17 (1.04 to 1.32)	<0.01
Herpes zoster infection and antiviral therapy	1.16 (0.99 to 1.36)	0.05	1.09 (0.93 to 1.28)	0.27
Any infection	1.44 (1.34 to 1.56)	<0.01	1.26 (1.16 to 1.36)	<0.01
No. of infections
0	1 (reference)	–	1 (reference)	–
1	1.38 (1.27 to 1.50)	<0.01	1.28 (1.18 to 1.40)	<0.01
2–4	1.88 (1.71 to 2.08)	<0.01	1.60 (1.44 to 1.77)	<0.01
5 or more	2.94 (2.58 to 3.36)	<0.01	2.18 (1.90 to 2.51)	<0.01
	Test for trend	<0.01	Test for trend	<0.01

^*Adjusted for Charlson Comorbidity Index, alcohol use, smoking history, prior use of immunosuppressive therapies and prior use of oral glucocorticoids.

IRR, incident rate ratio.