Table 4.

Risk of HPV infection in each subgroup.

Group	OR (95% CI)	pa
Any HPV infection
Healthy patients	Reference	–
Immunodeficient patients	5.797 (3.696–9.091)	<0.0001
Risk group	3.888 (3.369–4.487)	<0.0001
Benign lesions	2.686 (2.312–3.121)	<0.0001
Premalignant lesions	2.094 (1.904–2.304)	<0.0001
Oral or oropharyngeal SCC	3.097 (2.700–3.553)	<0.0001
HPV 16 infection
Healthy patients	Reference	–
Immunodeficient patients	9.400 (4.021–21.977)	<0.0001
Risk group	2.476 (1.167–5.255)	0.018
Benign lesions	N/C	–
Premalignant lesions	2.467 (2.121–2.870)	<0.0001
Oral or oropharyngeal SCC	1.725 (1.180–1.522)	0.005
HPV 18 infection
Healthy patients	Reference	–
Immunodeficient patients	3.894 (0.844–17.960)	0.081
Risk group	2.254 (0.793–6.402)	0.127
Benign lesions	3.044 (2.169–4.271)	<0.0001
Premalignant lesions	2.242 (1.839–2.740)	<0.0001
Oral or oropharyngeal SCC	2.051 (1.807–2.327)	<0.0001
HPV 16/18 infection
Healthy patients	Reference	–
Immunodeficient patients	7.833 (3.689–16.633)	<0.0001
Risk group	2.476 (1.324–4.629)	0.005
Benign lesions	2.040 (1.624–2.562)	<0.0001
Premalignant lesions	2.278 (2.017–2.573)	<0.0001
Oral or oropharyngeal SCC	1.477 (1.043–2.092)	0.028

N/C, not calculated because there was no valid case for analysis.

^aLogistic regression.