استفاده از داروهای تجویزی و بزهکاری آینده در میان نوجوانان بزهکار

Abstract Non-medical use of prescription drugs (NMUPD) by adolescents is a significant public health concern. The present study investigated the profile of NMUPD in 1349 adolescent offenders from the Pathways to Desistance project, and whether NMUPD predicted future delinquency using longitudinal data. Results indicated that increased frequency and recency of NMUPD in adolescent offenders are related to some demographic factors, as well as increased risk for violence exposure, mental health diagnoses, other drug use, and previous delinquency, suggesting that severity of NMUPD is important to consider. However, ANCOVA analyses found that NMUPD was not a significant predictor of drug-related, non-aggressive, or aggressive delinquency 12 months later beyond other known correlates of delinquency. Age, sex, exposure to violence, lower socioeconomic status, more alcohol use, and having delinquency histories were more important than NMUPD in predicting future delinquency. These findings suggest that although NMUPD is an important risk factor relating to many correlates of delinquency, it does not predict future delinquency beyond other known risk factors.

Introduction Over the last two decades opioids and other psychotherapeutic medications, such as tranquilizers, stimulants, and sedatives have been prescribed in greater frequency in the United States, especially to adolescents and young adults (Fortuna et al., 2010 and Thomas et al., 2006). Coupled with a corresponding increase in the non-medical use and abuse of those drugs, this has been topic of controversy and reason for great concern (Ford, 2008, Manchikanti and Singh, 2008, Novak et al., 2011, Thomas et al., 2006 and Young et al., 2012). The National Survey on Drug Use and Health (NSDUH) defines non-medical use of prescription drugs (NMUPD) as use of at least one psychotherapeutic drug from four categories of prescription-type drugs (i.e., opioids, tranquilizers, stimulants, and sedatives) “without a prescription of the individual's own or simply for the experience or feeling the drugs caused” (Substance Abuse and Mental Health Services Administration [SAMHSA], 2013b). National estimates of substance use in the general population show that the use of non-medical prescription drugs has become more prevalent than the use of other illicit drugs with the exception of marijuana; 2.4 million Americans engaged in NMUPD for the first time within the past year in 2012, an average of 6700 initiates per day (SAMHSA, 2013b). This is a significant public health concern: prescription opioid abuse alone was estimated to cost the U.S. $55.7 billion in 2007 (Birnbaum et al., 2011). 1.1. Adolescent substance use, delinquency, and NMUPD As with other forms of substance use, findings indicate that adolescents and young adults are at the greatest risk of NMUPD relative to other age groups (Novak et al., 2011, Substance Abuse and Mental Health Services Administration (SAMHSA), 2006 and Substance Abuse and Mental Health Services Administration (SAMHSA), 2013b), and numerous studies have explored NMUPD among adolescents (Ford, 2008, Johnston et al., 2011 and Young et al., 2012). NMUPD was the second most popular illicit drug for adolescents after marijuana in a nationally representative community sample, with a peak of 4.0% past month users among 16 and 17 year olds in the 2013 NSDUH. This finding extended to 12 to 13 year olds: NMUPD was the most prevalent illicit drug used, with 1.7% reporting past month use (SAMHSA, 2013b). In 2009, the NSDUH showed that among all past year adolescent users about 16% met the criteria for abuse or dependence, indicating that problematic levels of abuse are developing far earlier in the life course compared to other illicit drugs such as cocaine or heroin, where the median age of abuse and dependence is situated in the mid-20s (Novak et al., 2011). Beyond abuse and dependence, studies investigating life experiences and mental health symptoms have found that trauma, a history of significant witnessed violence, post-traumatic stress disorder (PTSD), and major depressive disorder (MDD) were associated with adolescent NMUPD use (Catalano et al., 2011, McCauley et al., 2010 and Schepis and Krishnan-Sarin, 2008). Further, NMUPD use has been linked with poor school performance and lower school bonding (Ford, 2009 and Schepis and Krishnan-Sarin, 2008) and delinquency (Ford, 2008). Overall, NMUPD users are at an increased risk for emergency room visits (SAMHSA, 2013a) and death (Centers for Disease Control and Prevention (CDC), 2012 and Paulozzi et al., 2012). Youth who engage in NMUPD are significantly more likely than their peers to use other illicit drugs and to combine prescription drugs with alcohol and other substances. These practices not only further increase the risk of involvement with the juvenile justice system, they also lead to increased risk for potentially dangerous drug interactions and their negative outcomes (Garnier et al., 2009 and McCabe et al., 2006). Clearly, NMUPD among juveniles is a large public health problem with significant consequences, yet studies investigating NMUPD in adolescent samples indicate that there is considerable variation in both prevalence of NMUPD and demographic, behavioral, and social correlates (Boyd et al., 2009 and Young et al., 2012). For example, in general NMUPD has been lower among racially and ethnically non-White adolescents compared to their White counterparts (McCabe et al., 2012, McCauley et al., 2010 and Substance Abuse and Mental Health Services Administration (SAMHSA), 2013b). Overall prevalence rates and trends in high risk samples of adolescents are missing from the literature. Adolescents are more likely than young adults to use multiple drugs, and a plethora of evidence suggests that there is a substantial overlap in NMUPD and the use of marijuana and other illicit drugs (Boyd et al., 2009, Catalano et al., 2011, Ford, 2008, McCabe et al., 2012, Substance Abuse and Mental Health Services Administration (SAMHSA), 2013b, Schepis and Krishnan-Sarin, 2008, Wu et al., 2006 and Young et al., 2012). Several researchers have thus suggested that NMUPD might simply be another form of illicit substance use, and that negative consequences of NMUPD might overlap with symptoms of polydrug use (Catalano et al., 2011, Ford, 2008 and Young et al., 2012). Possible explanations of the relationship between illicit substance use, alcohol, and NMUPD is that an adolescent who already is abusing substances might share some of the risk factors associated with NMUPD; he or she might already know where and how to access prescription drugs and receive less parental monitoring compared to non-using peers. Additionally, adolescents who binge drink, abuse alcohol, or use other illicit drugs may engage in NMUPD for similar affective reasons—either an attempt to numb affect or experience excitement (McCauley et al., 2010). There is some support for this hypothesis in data linking NMUPD to delinquency, with one study of students finding that NMUPD motivated by thrill-seeking, but not motivated by self-treatment, was connected to both other illicit drug use and delinquency (Boyd et al., 2009). A wealth of research documents the association between illicit drug use and an increased risk of general and aggressive delinquency among adolescents (Adams et al., 2013, Barnes et al., 2002, Doran et al., 2012, Ford, 2008 and Mason and Windle, 2002). Substance use has been associated with continuity in offending, decreased likelihood of desistance, and increased risk of reoffending; it also distinguished high level chronic offenders from less severe offender groups (Mulvey et al., 2010 and Schubert et al., 2011). While comparatively more limited than the general literature, there is some evidence that links NMUPD specifically with delinquency in adolescents (Adams et al., 2013, Boyd et al., 2009, Catalano et al., 2011 and Sung et al., 2005). One of the few studies focusing on NMUPD and delinquency is Ford's (2008) analysis of the connection between NMUPD and delinquency in the community sample of the 2005 NSDUH. In this study, results indicated that NMUPD overall, as well as specific categories of drugs (i.e., opioids, tranquilizers stimulants, and sedatives), was significantly associated with self-reported general delinquency in adolescents. Further, overall NMUPD and the non-medical use of opioids were associated with increased likelihood of arrest among 12 to 17 year old adolescents. The study found that in this sample, the use of other illicit drugs (not including marijuana) was more strongly associated with self-reported general delinquency and arrest than NMUPD. However, severity of drug use and use of marijuana were not included in the analyses and differential relationships of NMUPD to aggressive versus non-aggressive or drug-related delinquency were not investigated. Evidence regarding differential relationships of illicit drug use, alcohol use, and different types of delinquency is comparatively more equivocal than the relationship to general delinquency. Data from the most recent NSDUH show that youths aged 12 to 17 who had engaged in fighting or other delinquent behaviors in the past year were more likely than other youths to have used illicit drugs in the past month (SAMHSA, 2013b). These findings suggest that among adolescents in the community, illicit drug use compared with NMUPD is more directly associated with non-violent property-related crime. In contrast however, a wealth of research has shown that substance use confers an increased risk for aggression (versus general delinquency); with early use a particularly strong predictor of violent behavior (Doran et al., 2012, Hawkins et al., 2000 and Martel et al., 2009). Relationships between NMUPD and different delinquent behaviors have not yet been assessed, even though there is some evidence of potential differences in the association of NMUPD and different forms of delinquency. One longitudinal study found that the non-medical use of prescription opioids among adolescents was associated with violent behavior, but explained little variance in property crime (Catalano et al., 2011), and, as stated above, a study with high-school students found that only NMUPD motivated by sensation seeking, and not self-treatment, was associated with delinquency (Boyd et al., 2009). However, in a sample of justice system-involved, high-risk youth, substance use was equally related to drug-related, interpersonal, and property delinquency with stability over time (D'Amico, Edelen, Miles, & Morral, 2008). 1.2. Substance use and NMUPD among adolescent offenders The increased prevalence of mental health problems and substance use disorders together with an elevated rate of substance use among adolescent offenders in the juvenile justice system is a well-known issue (Chassin, 2008, Shook et al., 2011, Vaughn et al., 2007 and Vaughn et al., 2005). As mentioned above, substance use disorders are linked to continued offending and violence in community and offender samples of adolescents (Adams et al., 2013, Chassin, 2008 and Mulvey et al., 2004). Among juvenile offenders, the presence of a substance use disorder is consistently associated with more re-arrests, more self-reported antisocial activity, more drug-related, interpersonal, and property delinquency, and less engagement in gainful activity, both cross-sectionally and over time (D'Amico et al., 2008, Mulvey et al., 2004 and Schubert et al., 2011). Our knowledge of prevalence and correlates of NMUPD among this high-risk population is limited to a few studies examining correlates of mostly binary lifetime NMUPD in currently incarcerated samples. One of the few studies taking into account the severity of drug use in this population examined patterns of illicit drug use and mental health concerns among a state population of 723 incarcerated juvenile offenders and found that level of lifetime poly-substance use and severity of problems stemming from alcohol and drug use were associated with severity of mental health symptoms, including past traumatic experiences (Vaughn et al., 2007). Links between drug use and delinquency or NMUPD specifically were not assessed. The only study examining the correlates of NMUPD in a sample of confined adolescents was conducted with the population of one urban detention center in Ohio (Alemagno, Stephens, Shaffer-King, & Teasdale, 2009). It showed that overall 10% of incarcerated male youth reported lifetime NMUPD. Arrestees reporting NMUPD had higher levels of overall other illicit drug use, more alcohol problems, reported more trauma and problems with anger management, as well as more risky sexual behaviors. However, frequency or recency of NMUPD use as well as any relation to non-aggressive or drug-related delinquency was not reported. Finally, there was one study with 227 incarcerated juveniles comparing youthful offenders who sold drugs with those who did not sell drugs on substance use and other behaviors (Shook et al., 2011). Results suggested that juveniles engaging in either selling marijuana or hard drugs were using marijuana, other illicit drugs, and NMUPD at substantially elevated rates, suggesting a significant overlap between own substance use and dealing of drugs. In summary, there is sparse knowledge about NMUPD use specifically among adolescent offenders. Given the high prevalence of substance use, mental health issues and thrill-seeking behaviors in offenders, they are at increased risk for NMUPD. Given national trends in NMUPD it seems especially important to understand the unique contribution of NMUPD to future patterns of delinquency and other substance use. Investigating whether NMUPD uniquely contributes to patterns of recidivism has potentially important implications for treatment of substance use problems and targeted prevention efforts in this population. 1.3. Current study The present study contributes to the literature in several ways. Serious adolescent offenders are a group with an especially elevated risk of engaging in both substance use and continued delinquency. While there is some evidence that NMUPD is associated with delinquency in community samples, limited data on the characteristics of NMUPD users among serious adolescent offenders exist. Additionally, the existing knowledge about NMUPD use among offenders largely stems from incarcerated samples reporting on past behavior; there is a dearth of longitudinal research that investigates how NMUPD influences delinquency over time above and beyond known correlates of delinquency. The present study describes and compares serious adolescent offenders who have never engaged in NMUPD, engaged in NMUPD only experimentally or long ago, and recent frequent users. Further, the present study investigates the relationship between NMUPD and different forms of delinquency; there are no studies to date that investigate the influence of NMUPD on drug-related, non-aggressive, and aggressive delinquency separately. Finally, the present study investigates these relationships longitudinally and investigates whether NMUPD predicts different types of future delinquency above and beyond other known correlates of delinquency, closing a substantial gap in knowledge, and providing data that can inform prevention and treatment of this high-risk group of adolescent offenders. Thus, the purposes of the current study were to investigate two research questions: (1) What is the profile of NMUPD among serious adolescent offenders? and (2) What is the unique contribution of NMUPD in predicting future drug-related, non-aggressive, and aggressive delinquency among serious adolescent offenders beyond known correlates of delinquency?

. Results 3.1. Missing data, normality, and multicollinearity analyses A missing data analysis was conducted on all independent variables and the missing data were found to be missing completely at random (MCAR) according to Little's chi-square statistic (Little, 1988), χ2 = 425.53, df = 405, p = .23. All independent variables were assessed for non-normality. Many variables were skewed and kurtotic, including the delinquency histories, mental health, and illicit drug use variables. However, normal distributions of the predictors are not an assumption that needs to be met for chi-square analyses, ANOVAs, or ANCOVAs (Field, 2013). Also, simulation studies have found ANOVAs are robust against the normality assumption (e.g., Schmider, Ziegler, Danay, Beyer, & Bühner, 2010). Similarly ANCOVAs are robust against the normality assumption (Barrett, 2011 and Rutherford, 2012). However, as suggested by Field (2013) the standardized residual histogram plots were assessed for normality. Although there was some suggestion from visual inspections of the standardized residuals of non-normality in the drug-related and non-aggressive delinquency models this assumption is primarily a concern with small sample sizes as there may not be enough power to detect anything but gross departures (Schwarz, 2013). Given the large sample size in the current study the researchers did not make any alterations to the data. Additionally, multicollinearity was assessed with a visual inspection of the correlation table and collinearity statistics from regression results. No correlations between all variables were greater than r = .80 (range .00-.63; Field, 2013), all tolerances were above .20 (range .57–.99; Menard, 1995) and VIFs were less than 10 (range 1.01–1.80; Myers, 1990) suggesting no problems with collinearity. 3.2. Baseline differences based on NMUPD user group Table 1 reports the findings from the χ2 and ANOVA tests assessing baseline differences in demographics and known correlates of delinquency (i.e., violence exposure, mental health, other drug use, delinquency history) across patterns of NMUPD. There were significant group differences on all measures except SES and proportion of time spent with no community access. Black participants were overrepresented in the “never used NMUPD” group, whereas Hispanics were overrepresented in the “used NMUPD at least once in a lifetime” group. Whites and Hispanics were equally overrepresented in the “current NMUPD user” category. Additionally, NMUPD users compared to non-users were significantly older, although there were no differences between NMUPD at least once in lifetime and current NMUPD users. Proportionally more females reported NMUPD use than non-use; this was particularly evident in the current NMUPD use category. Table 1. NMUPD group differences in baseline demographic factors and correlates of delinquency (N = 1349). Characteristic: Group 1Never used NMUPD (n = 944) Group 2Used NMUPD in lifetime (n = 258) Group 3Current NMUPD users (n = 147) Univariate test of difference Demographic factors Race/ethnicity χ2(6) = 100.93 ⁎⁎⁎ White [% (n)] 14.6 (138) 30.6 (79) 38.8 (57) Black [% (n)] 48.5 (458) 27.9 (72) 17.7 (26) Hispanic [% (n)] 32.6 (308) 34.5 (89) 38.8 (57) Other [% (n)] 4.3 (40) 7.0 (18) 4.7 (7) Sex [% male (n)] 88.6 (836) 83.3 (215) 77.6 (114) χ2(2) = 15.57 ⁎⁎⁎ Mean age (SD) and 15.93 (1.15) 16.36 (1.12) 16.21 (1.01) F(2, 1346) = 17.04 ⁎⁎⁎ Mean SES (SD) 51.83 (12.63) 51.20 (11.87) 49.23 (10.71) F(2, 1338) = 2.89 Proportion of time with no community access mean (SD) 0.45 (0.32) 0.50 (0.32) 0.45 (0.32) F(2, 1167) = 2.63 Violence exposure Witnessed violence mean (SD) and 3.51 (1.95) 4.27 (1.89) 4.63 (1.64) F(2,1346) = 32.61 ⁎⁎⁎ Directly Victimized Mean (SD) , and 1.27 (1.34) 2.09 (1.45) 2.63 (1.48) F(2,1346) = 83.51 ⁎⁎⁎ Total score mean (SD) , and 4.78 (2.85) 6.36 (2.92) 7.25 (2.77) F(2,1346) = 67.60 ⁎⁎⁎ Mental health Major depressive disorder [% Yes (n)] 5.2 (48) 9.4 (24) 17.6 (25) χ2(2) = 30.22 ⁎⁎⁎ PTSD [% yes (n)] 4.3 (40) 9.8 (25) 14.8 (21) χ2(2) = 28.11 ⁎⁎⁎ Alcohol abuse [% yes (n)] 8.3 (76) 14.9 (37) 25.0 (35) χ2(2) = 37.21 ⁎⁎⁎ Alcohol dependence [% yes (n)] 4.2 (38) 21.0 (52) 30.0 (42) χ2(2) = 128.07 ⁎⁎⁎ Drug abuse [% yes (n)] 21.3 (194) 34.3 (85) 45.7 (64) χ2(2) = 47.15 ⁎⁎⁎ Drug dependence [% yes (n)] 7.6 (69) 30.6 (76) 42.1 (59) χ2(2) = 161.47 ⁎⁎⁎ Other drug use Alcohol use mean (SD) , and 3.76 (2.55) 5.81 (2.48) 6.50 (2.50) F(2, 1346) = 120.67 ⁎⁎⁎ Marijuana use mean (SD) and 5.60 (3.35) 8.08 (2.01) 8.76 (0.98) F(2, 1346) = 122.56 ⁎⁎⁎ Illicit drug use mean (SD) , and 0.74 (2.21) 5.19 (5.46) 9.50 (7.29) F(2,1346) = 403.26 ⁎⁎⁎ Delinquency history severity index Drug delinquency mean (SD) , and 0.32 (0.36) 0.65 (0.37) 0.77 (0.33) F(2,1343) = 154.58 ⁎⁎⁎ Non-aggressive delinquency mean (SD) , and 0.28 (0.22) 0.48 (0.22) 0.57 (0.22) F(2,1342) = 98.31 ⁎⁎⁎ Aggressive delinquency mean (SD) , and 0.26 (0.18) 0.37 (0.21) 0.44 (0.23) F(2,1343) = 76.05 ⁎⁎⁎ Values are n (unweighted) and % (weighted) unless otherwise specified. Bonferonni adjustments were made for all post hoc comparisons using continuous variables. NMUPD = non-medical use of prescription drugs, PTSD = post traumatic stress disorder. ⁎⁎⁎ p < .001. a Significant difference (p < .05) between group 1 and group 2. b Significant difference (p < .05) between group 1 and group 3. c Significant difference (p < .05) between group 2 and group 3. Table options In reference to violence exposure, a linear trend was evident at baseline with more violence exposure being reported with more NMUPD. All three groups of NMUPD users were significantly different from one another on direct victimization and total violence exposure. For witnessed violence, youth who never used NMUPD witnessed less violence than both other groups of NMUPD users, who were not different from one another. Similarly, there were baseline NMUPD group differences in all mental health categories. These differences were linear: youth with no NMUPD had a lower proportion of lifetime mental health diagnoses compared with youth who had used prescription drugs non-medically but not recently; those youth in turn had a lower proportion of diagnoses than youth who were current NMUPD users. There also were significant differences at baseline between all three NMUPD groups in their lifetime use of alcohol, marijuana, and illicit drugs. The only exception was lifetime marijuana use, where youth who never used NMUPD reported lower lifetime use than both other groups, who were not different from one another. Finally, there were baseline differences between the three NMUPD groups on lifetime delinquency. As NMUPD use became more frequent and recent, lifetime drug-related, non-aggressive, and aggressive delinquent acts increased. Analyses were also conducted with past 30 days (mental health diagnoses), past year (mental health diagnoses), and past 6 months (other drug use, past delinquency) data as available. The only substantial differences from the lifetime results were that for: (1) past 30 days alcohol dependency more mental health diagnoses were found in the used NMUPD at least once in lifetime as compared to current NMUPD users, χ2(2) = 8.80, p < .05, and (2) drug-related offenses in the past 6 months the differences were between current NMUPD users and the other two groups, F(2, 841) = 39.11, p < .001. 3.3. ANCOVAs predicting future delinquency 3.3.1. Drug-related delinquency Preliminary ANCOVA analyses found the following significant predictors of drug-related delinquency: SES, total violence exposure, drug abuse severity, lifetime alcohol use, previous drug-related delinquency, and NMUPD group membership (results of these analyses are available from the first author). In the final ANCOVA model (see Table 2) having a lower SES, more violence exposure, and a history of more previous drug-related delinquency were the significant predictors, with previous drug-related delinquency as the strongest predictor (η2p = .009) after accounting for all other significant covariates. NMUPD was not a significant predictor (η2p = .003). Table 2. Final ANCOVA models for predicting future delinquency in adolescent offenders. Predictors F df p η2p Drug-related delinquency SES 5.18 1, 1116 .023 .005 Total violence exposure 4.63 1, 1116 .032 .004 Drug abuse severity 0.23 1, 1116 .631 .000 Lifetime alcohol use 2.25 1, 1116 .134 .002 Drug-related delinquency history 10.62 1, 1116 .001 .009 NMUPD 1.46 2, 1116 .233 .003 Non-aggressive delinquency Age 4.10 1, 1124 .043 .004 Total violence exposure 0.13 1, 1124 .716 .000 Alcohol dependency severity 0.54 1, 1124 .465 .000 Lifetime alcohol use 2.61 1, 1124 .107 .002 Lifetime illicit drug use 1.31 1, 1124 .253 .001 Non-aggressive delinquency history 5.46 1, 1124 .020 .005 Aggressive delinquency history 3.14 1, 1124 .077 .003 NMUPD 1.78 2, 1124 .169 .003 Aggressive delinquency Sex 10.93 1, 1173 .001 .009 Age 25.31 1, 1173 < .001 .021 Total violence exposure 27.18 1, 1173 < .001 .023 MDD severity 1.56 1, 1173 .211 .001 Alcohol dependency severity 1.18 1, 1173 .277 .001 Drug abuse severity 0.01 1, 1173 .932 .000 Drug dependency severity 0.49 1, 1173 .487 .000 Lifetime alcohol use 0.06 1, 1173 .003 .008 Aggressive delinquency history 86.48 1, 1173 < .001 .069 NMUPD 1.46 2, 1173 .234 .002 MDD = major depressive disorder, NMUPD = non-medical use of prescription drugs, SES = socioeconomic status. Table options 3.3.2. Non-aggressive delinquency Preliminary ANCOVA analyses found the following significant predictors of non-aggressive delinquency: age, total violence exposure, alcohol dependency severity, lifetime alcohol use, lifetime illicit drug use, previous non-aggressive delinquency, previous aggressive delinquency history, and NMUPD group membership. In the final ANCOVA model (see Table 2) being older and involved in more non-aggressive delinquency were significant predictors of future non-aggressive delinquency, with previous non-aggressive delinquency as the strongest predictor (η2p = .005). NMUPD was not a significant predictor (η2p = .003). 3.3.3. Aggressive delinquency Preliminary ANCOVA analyses found the following significant predictors of aggressive delinquency: sex, age, total violence exposure, MDD severity, alcohol dependency severity, drug abuse severity, drug dependency severity, lifetime alcohol use, previous aggressive delinquency, and NMUPD group membership. In the final ANCOVA model (see Table 2) being male and older, and experiencing more violence exposure, higher lifetime alcohol use, and more previous aggressive delinquency were significant predictors of future aggressive delinquency. The strongest predictor was previous aggressive delinquency (η2p = .069). NMUPD was not a significant predictor (η2p = .002).