Among 870 adolescents, 21 deaths at an average age of 22.8±2.9 years were observed. In 12 cases for whom the information could be collected, the causes of death were MVAs (n=5), homicide (n=4), suicide (n=1), drug overdose (n=1), or other accident (n=1). Described by gender, ethnicity and adolescent-onset SUD, the numbers of deaths and rates are presented in .
Frequencies and proportions of deaths by gender, ethnic group and SUD status
In Cox regression models examining the main effects of individual independent variables, survival time was significantly predicted by gender (χ2=21.5, d.f.=1, p<.001: male < female) and ethnic group (χ2=10.2, d.f.=1, p=.001; AA<W), and was not predicted by SES (χ2=1.4, d.f.=1, p=.2). Survival time (present < absent) was significantly predicted by SUDs (4.1, d.f.=1, p=.04), Hazardous Use (χ2=7.9, d.f.=1, p=.005) and Selling Drugs (χ2=12.1, d.f.=1, p<.001), and was not predicted by Suicide Attempts (χ2=0.4, d.f.=1, p=.5). Recruitment source also predicted survival (χ2=5.6, d.f.=1, p=.02: Clinical < Community). After taking SUDs into consideration, however, recruitment source was not a significant survival time predictor (χ2=2.1, d.f.=1, p=.15).
In the analysis with subject categories, the observation of only one death among females resulted in non-converging models when examining female subgroups. Female groups were consequently combined. The resulting five group variable significantly predicted survival time (χ2=38.0, d.f.=1, p<.001: ). Compared to females, each of the male groups had significantly diminished survival time. Among males, the groups were significantly different (χ2=17.1, d.f.=1, p=.001). Compared to W males without SUDs, W males with SUDs (χ2=0.1, d.f.=1, p=.8) and AA males without SUDs (χ2=3.5, d.f.=1, p=.06) were not significantly different, whereas AA males with SUDs had significantly diminished survival time (χ2=11.1, d.f.=1, p=.001). Utilizing W males without SUDs as a comparison group, mortality risk among AA males with SUDs was increased by an Odds Ratio of 10.3 (95% Confidence Interval 2.6, 40.4).
Survival plots by gender, ethnic group, and adolescent substance use disorder. Abbreviations: M: male; W: white; AA: African American; SUD: adolescent-onset substance use disorder