Table 2 Vaping dependence and smoking dependence measures among adult AI dual EC and cigarette users (N = 44)
Vaping Dependence Measures | % | Smoking Dependence Measures | % | |||
|---|---|---|---|---|---|---|
Minutes after waking use first EC | Minutes after waking use first cigarette | |||||
 5 or less | 31% |  5 or less | 24% | |||
 6–30 | 24% |  6–30 | 31% | |||
 31–120 | 24% |  31–120 | 38% | |||
 121+ | 21% |  121+ | 7% | |||
Nights per week wake to use EC | Nights per week wake to smoke | |||||
 Never/less than weekly | 73% |  Never/less than weekly | 54% | |||
 1 to 2 | 12% |  1 to 2 | 23% | |||
 3 or more | 15% |  3 or more | 23% | |||
Continue using EC because hard to quit | Continue to smoke because hard to quit | |||||
 Yes | 44% |  Yes | 80% | |||
 No | 56% |  No | 20% | |||
Ever have strong cravings to use EC | Ever have strong cravings to smoke | |||||
 Yes | 33% |  Yes | 84% | |||
 No | 67% |  No | 16% | |||
How strong were urges to vape, past week | How strong were urges to smoke in past week | |||||
 None | 44% |  None | 0% | |||
 Slight | 34% |  Slight | 18% | |||
 Moderate | 10% |  Moderate | 25% | |||
 Very/extremely strong | 22% |  Very/extremely strong | 57% | |||
Hard to keep from using EC | Hard to keep from smoking | |||||
 Yes | 36% |  Yes | 58% | |||
 No | 64% |  No | 42% | |||
WHEN HAVE NOT USED [EC; tobacco] for a while OR when you tried to stop [vaping; smoking] … | ||||||
Irritable because can’t use EC | Irritable because can’t smoke | |||||
 Yes | 32% |  Yes | 73% | |||
 No | 68% |  No | 27% | |||
Nervous because can’t vape | Nervous because can’t smoke | |||||
 Yes | 32% |  Yes | 66% | |||
 No | 68% |  No | 34% | |||
Composite Dependence Scores | p-value* | |||||
Heaviness of Vaping Index [32] | Mean (SD) | 2.07 (1.76) | Heaviness of Smoking Index [33] | Mean (SD) | 2.36 (1.66) | .2155 |
PSDI-EC [32] | Mean (SD) | 6.42 (4.84) | PSDI-smoking [32] | Mean (SD) | 11.02 (5.00) | <.0001 |