Immunogenicity of Three Different Influenza Vaccines against Homologous and Heterologous Strains in Nursing Home Elderly Residents

Table 3

Multivariate analysis of variables associated with 4-fold HI-antibody titer increases according to heterologous virus strains.

Variables	A/H1N1/NewCaledonia/20/99		A/H3N2/Wisconsin/67/2005		B/Malaysia/2506/2004
	OR	95% CI	OR	95% CI	OR	95% CI
Age (<85)	0.784	(0.421–1.458)	1.515	(0.829–2.768)	0.681	(0.344–1.347)
Gender (males)	0.465	(0.177–1.219)	1.280	(0.507–3.234)	1.239	(0.463–3.317)
Underlying diseases	1.431	(0.783–2.615)	0.897	(0.490–1.644)	1.598	(0.811–3.149)
Previous vaccinations	1.447	(0.738–2.835)	0.806	(0.417–1.559)	0.307	(0.151–0.626)
Prevaccination titre (≥1 : 40)	1.803	(0.976–3.333)	0.676	(0.355–1.286)	0.891	(0.447–1.776)
Split versus Sub/MF59	0.287	(0.150–0.547)	0.436	(0.226–0.842)	0.795	(0.404–1.564)
SVV versus Sub/MF59	0.400	(0.180–0.893)	0.402	(0.167–0.965)	0.215	(0.060–0.774)