Age of First Substance Use in a High Risk Population: Do Race and Gender Matter?

Introduction:

Adolescents with substance use are at high risk of suffering from health and legal consequences as adults.  National surveys and longitudinal studies have examined substance use prevalence and age at first use among adolescents in the general population.  Few studies have assessed early substance use patterns of an adult high risk population with substance use.  This study examines differences in age at first substance use by race and gender in a criminal justice population.

Methods:

Data were collected from adults in a case management community corrections diversion program for substance users that is an alternative to incarceration and involves substance abuse rehabilitation.  Study participants smoked cigarettes and agreed to participate in a study on smoking cessation (R01CA141663, PI: Cropsey).  Trained personnel performed semi-structured interviews using the Addiction Severity Index (ASI) to obtain demographics (i.e. race, age, and gender) and age at first substance use including nicotine, cannabis, alcohol, opiates, sedatives, and cocaine.  The population was stratified by age and gender into 4 groups: Black men, Black women, White men, and White women.  ANOVAs were used to compare mean age differences of first use of each substance.  Tukey’s Honestly Significant Difference tests were used to describe the differences in age at first substance use between the four groups. 

Results:

Of the 611 participants analyzed, 67.1% were male, and 64.6% were Black.  Mean age was 36.9 years (SD 11.1).  After stratification, 287 (47%) were Black men, 108 (18%) were Black women, 123 (20%) were White men, and 93 (15%) were White women.  All participants had used nicotine with mean age of onset of 14.5 years (range 13.5 years in White women to 15.6 years in Black women).  Mean age of onset for cannabis and alcohol was 15.2 and 14.3 years, respectively.  Black women were significantly older than White men (1.8 years difference, p = 0.002) and white women (2.0 years difference, p = 0.001) at first nicotine use.  Men did not differ in age of first tobacco use based on race.  Black men initiated marijuana at younger ages than black women (mean difference 1.5 years, p = 0.006).   White men reported both first opiate use and first cocaine use 4.3 years before black men (p =0.009 and p < 0.0001, respectively).  There were no significant differences in alcohol first use by race and gender. 

Conclusions:

In a high risk population for substance abuse, initiation patterns differ based on race and gender across different substances.  There was no significant difference in use initiation for alcohol among the groups.  Substance use disorders and substance prevention strategies can be enhanced by these results, especially for practitioners caring for high risk youth.