Table 3.

Tobacco use characteristics of hepatitis C+ versus hepatitis C− participants.

Characteristic	NHANES, 1999–2014: Smokers only
	HCV− (N=8,508)	HCV+ (N=312)	P
Smoking frequency
Daily	80.0%	87.5%	0.04
Non-daily	15.8%	10.1%
Not classifiable	4.3%	2.4%
Nicotine dependence*
Very low	45.7%	39.1%	0.46
Low-Moderate	24.3%	25.7%
Moderate	19.0%	21.6%
High	11.0%	13.6%
Cigarettes per day (95% CI)	14.4 (14.0–14.9)	16.0 (14.2–17.7)	0.09
Cotinine level, ng/mL (95% CI)	207 (202–213)	264 (244–283)	<0.001
Number of years smoking (95% CI)	23.9 (23.4–24.3)	30.4 (29.2–31.7)	<0.001
Smokes menthol cigarettes (%)	27.1%	29.2%	0.54

Note: HCV− =without active hepatitis C infection, HCV+=with active hepatitis C infection, CI=confidence interval.

^*Derived from the Heaviness Smoking Index.¹⁵