Combined Effect of Secondhand Smoking and Alcohol Drinking on Risk of Persistent Human Papillomavirus Infection

Table 1

Odds ratios of active smoking and secondhand smoking for risk of HR-HPV infection and HR-HPV persistence.

	HR-HPV infection at enrollment (n = 9,846)			1-year HR-HPV persistence (n = 1,237)			2-year HR-HPV persistence (n = 481)
	Negative	Positive	Multivariate OR	Negative	Persistence	Multivariate OR	Negative	Persistence	Multivariate OR
Characteristics	(n = 8,866)	(n = 980)	(95% CI)	(n = 1,132)	(n = 145)	(95% CI)	(n = 432)	(n = 49)	(95% CI)
Active smoking
Nonsmoking	8,145 (90.3)	876 (9.7)	1 (ref.)	1,002 (88.5)	130 (11.5)	1 (ref.)	388 (89.4)	46 (10.6)	1 (ref.)
Smoking	721 (87.4)	104 (12.6)	1.18 (0.94–1.48)	90 (85.7)	15 (14.3)	0.98 (0.53–1.80)	44 (93.6)	3 (6.4)	0.38 (0.11–1.37)
Secondhand smoking (SHS)
Non-SHS	5,628 (90.4)	601 (9.6)	1 (ref.)	672 (88.4)	88 (11.6)	1 (ref.)	251 (89.6)	29 (10.4)	1 (ref.)
SHS	3,238 (89.5)	379 (10.5)	1.01 (0.88–1.17)	420 (88.1)	57 (11.9)	0.86 (0.59–1.23)	181 (90.1)	20 (9.9)	0.95 (0.51–1.78)
SHS in nonsmokers
Non-SHS in nonsmokers	5,199 (90.6)	540 (9.4)	1 (ref.)	619 (88.7)	79 (11.3)	1 (ref.)	230 (89.5)	27 (10.5)	1 (ref.)
SHS in nonsmokers	2,946 (89.8)	336 (10.2)	1.00 (0.86–1.16)	383 (88.3)	51 (11.7)	0.89 (0.62–1.29)	158 (89.3)	19 (10.7)	1.14 (0.61–2.13)
Alcohol drinking
Nondrinker	4242 (91.2)	410 (8.8)	1 (ref.)	580 (90.8)	59 (9.2)	1 (ref.)	231 (91.7)	21 (8.3)	1 (ref.)
Drinker	4056 (88.7)	519 (11.3)	1.19 (0.97–1.46)	447 (84.8)	80 (15.2)	1.44 (0.87–2.39)	177 (86.3)	28 (13.7)	3.08 (1.22–7.77)

“Negative” or “Positive” indicates the result of detection for 13 DNA types of high risk-human papillomavirus (HR-HPV) (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) using Hybrid Capture II.
All variables were adjusted for age (as continuous) and BMI (as continuous) as well as for marital status, oral contraceptive use, menopausal status, education level, number of children, active smoking status (for alcohol drinking), passive smoking (for alcohol drinking), and alcohol drinking status (for smoking).
Non-SHS indicates persons who are not exposed to secondhand smoking at home or in the workplace, regardless of active smoking status.
Secondhand smoking (SHS) in nonsmokers was defined as having never smoked in life but having been exposed to SHS.