Table 3.

Weighted multinomial logistic regressiona examining the association between e-cigarette use and cigarette smoking among adult survivors of smoking-related cancersb in the United States: National Health Interview Survey 2014–2017

Association between e-cigarette use and former smoking (outcome reference category: never smokers)
VariableCrude RRR (95% CI)Adjusted RRR (95% CI)P value for adjusted RRR
E-cigarette use
 Never userReferenceReferenceReference
 Former user4.75 (2.24–10.08)6.41 (3.02–13.57)<0.001
 Current user9.84 (1.94–49.87)14.88 (2.73–71.05)0.002
Age
 18–44 yearsReferenceReferenceReference
 45–64 years2.84 (1.50–3.47)2.18 (1.39–3.42)0.001
 ≥65 years4.05 (2.72–6.03)4.51 (2.94–6.92)<0.001
Gender
 MaleReferenceReferenceReference
 Female0.42 (0.34–0.52)0.53 (0.42–0.67)<0.001
Regionc
 WestReferenceReferenceReference
 South1.19 (0.88–1.60)1.31 (0.96–1.77)0.092
 Midwest1.36 (1.00–1.85)1.43 (1.03–1.98)0.031
 Northeast1.34 (0.92–1.95)1.33 (0.91–1.96)0.138
Alcohol use
 Lifetime abstainerReferenceReferenceReference
 Former drinker4.04 (2.85–5.73)3.74 (2.60–5.37)<0.001
 Current light/moderate drinker3.56 (2.69–4.72)3.91 (2.91–5.25)<0.001
 Current heavy drinker7.64 (3.88–15.05)7.90 (3.85–16.24)<0.001
Association between e-cigarette use and cigarette smoking (outcome reference category: never smokers)
E-cigarette use
 Never userReferenceReferenceReference
 Former user59.95 (28.80–124.78)54.48 (25.68–115.57)<0.001
 Current user99.87 (20.35–490.01)82.89 (16.54–415.37)<0.001
Age
 18–44 yearsReferenceReferenceReference
 45–64 years0.85 (0.60–1.22)1.10 (0.62–1.93)0.746
 ≥65 years0.34 (0.23–0.49)0.74 (0.42–1.28)0.276
Gender
 MaleReferenceReferenceReference
 Female1.03 (0.78–1.36)0.85 (0.62–1.18)0.338
Regionc
 WestReferenceReferenceReference
 South1.74 (1.20–2.52)1.93 (1.18–3.18)0.009
 Midwest1.90 (1.26–2.88)1.95 (1.17–3.24)0.010
 Northeast1.34 (0.83–2.17)1.77 (0.97–3.22)0.061
Alcohol use
 Lifetime abstainerReferenceReferenceReference
 Former drinker4.91 (2.95–8.16)4.39 (2.36–8.17)<0.001
 Current light/moderate drinker3.97 (2.52–6.26)3.22 (1.81–5.73)<0.001
 Current heavy drinker15.89 (7.31–34.55)13.97 (5.96–32.78)<0.001
  • aOutcome variable: cigarette smoking (current smokers vs. never smokers; former smokers vs. never smokers). Covariates (in addition to e-cigarette use): age, gender, region, and alcohol use.

  • bSmoking-related cancers defined as cancers of the bladder, cervix, colon, esophagus, kidney, larynx (windpipe), liver, lung, mouth/tongue/lip, pancreas, rectum, stomach, and throat (pharynx).

  • cRegions as defined by the U.S. Census Bureau.