Tobacco use disorder and the risk of completed suicide in VHA

Abstract

are to calculate TIJ and to examine factors associated with TIJ in a sample of drug injectors. Methods: As part of an exploratory study on injection drug initiation, interviewswere conductedwith drug injectors recruited at outreach sites in Los Angeles and San Francisco, CA (n=549) during 2011–12. Interviews covered demographics, family history, drug use and drug injection initiation among others. TIJ was calculated by subtracting age at first drug injection from age of first illicit drug use. We used multivariate linear regression to determine factors independently associated with TIJ. Results: The sample was 33%White, 32% Black, 25% Latino, 27% female, and 60% homeless. Mean age was 46.9 (IQR 41, 56) and mean years of drug injection were 24.8 (IQR 13, 36). Mean age of first illicit drug use was 13.8 (IQR 12, 15) andmean age of injection initiationwas22.1 (IQR16, 26).MeanTIJ for the samplewas8.4 (IQR 2, 12) years. In a multivariate linear regression model, we found that drug types ever usedwere associatedwith TIJ (crack use =+2.9 years, p =0.004; powder cocaine use =+3.3 years, p<0.001; heroin use =−3.2 years,p=0.009; prescription stimulants use =−2.6 years, p=0.001). Any substance abuse treatment prior to injection was associated with longer TIJ (+3.9 years, p<0.001), while being born after 1979 (−2.9, p=003) and having your first injection administered by a familymember (−3.4 years, p=0.006) or self (−2.1 years, p=0.016) were associated with shorter TIJ. Conclusions: TIJ was influenced by drug type, substance abuse treatment, birth cohort, and injection initiator characteristics. These data highlight the need for surveillance of emerging trends in injection drug use and novel prevention strategies targeting transitions to injection among at-risk populations. Financial support: NIDA grant number R01DA027689 and R01DA030427.