Brief original report: Does smoking status provide information relevant to screening for other substance use among US adults?

We assessed whether tobacco screening provides clinically meaningful information about other substance use, including alcohol and other drug use, potentially facilitating targeting of screening for substance use. Using data from the Veterans Aging Cohort Study survey sample (VACS; N = 7510), we calculated test performance characteristics of tobacco use screening results for identification of other substance use including sensitivity, specificity, positive-likelihood-ratio (+LR = [sensitivity/(1-specificity)]: increase in odds of substance use informed by a positive tobacco screen), and negative-likelihood-ratio (-LR: [(1-sensitivity)/specificity]: reduction in odds of substance use informed by a negative tobacco screen). The sample was 95% male, 75% minority, and 43% were current and 33% were former smokers. Never smoking, versus any history, indicated an approximate four-fold decrease in the odds of injection drug use (-LR = 0.26), an approximate 2.5-fold decrease in crack/cocaine (-LR = 0.35) and unhealthy alcohol use (-LR = 0.40), an approximate two-fold decrease in marijuana (-LR = 0.51) and illicit opioid use (-LR = 0.48), and an approximate 30% decrease in non-crack/cocaine stimulant use (-LR = 0.75). Never smoking yielded more information than current non-smoking (never/former smoking). Positive results on tobacco screening were less informative than negative results; current smoking, versus former/never smoking, provided more information than lifetime smoking and was associated with a 40% increase in the odds of non-crack/cocaine stimulant use (+LR = 1.40) and opioid use (+LR = 1.44), 50% increase in marijuana use (+LR = 1.52) and injection drug use (+LR = 1.55), and an 80-90% increase in crack/cocaine use (+LR = 1.93) and unhealthy alcohol use (+LR = 1.75). When comprehensive screening for substance use is not possible, tobacco screening may inform decisions about targeting substance use screening.