Table 2.

Geometric mean levels (GML) of pre- and post-vaccination antibody levels in patients with and without a history of serious infections after vaccination in all patients, and RA and SpA patients respectively

All patients	No serious infections after vaccination	Serious infections after vaccination
	N = 470	N = 27
	Antibody levels (mg/L)	Antibody levels (mg/L)
	GML; 95% CI	GML; 95% CI
Serotype 6B
Pre-vaccination	1.8 (1.6-2.1)	1.1 (0.6-1.9)
Post-vaccination	4.1 (3.5-4.8)	2.2 (1.3-3.8)
Serotype 23 F
Pre-vaccination	0.8 (0.7-0.9)	0.4 (0.2-0.7)
Post-vaccination	2.6 (2.2-3.0)	1.5 (0.9-2.3)
RA patients	No serious infections after vaccination	Serious infections after vaccination
Serotype 6B
Pre-vaccination	1.7 (1.4-2.1)	1.0 (0.5-1.8)
Post-vaccination	3.1 (2.5-3.9)	2.0 ( 1.1-3.7)
Serotype 23 F
Pre-vaccination	0.7 (0.6-0.8)	0.3 (0.2-0.7)
Post-vaccination	1.8 (1.4-2.1)	1.4 (0.8-2.4)
SpA patients	No serious infections after vaccination	Serious infections after vaccination
Serotype 6B
Pre-vaccination	1.9 (1.6-2.4)	2.2 (0.5-9.8)
Post-vaccination	5.2 (4.1-6.5)	3.6 (0.7-17.4)
Serotype 23 F
Pre-vaccination	0.8 (0.7-1.0)	0.7 (0.2-2.3)
Post-vaccination	3.6 (3.0-4.5)	1.9 (0.5-6.9)

CI, confidence interval; RA, rheumatoid arthritis; SpA, spondylarthropathy.