Normalization of Prevention Principles and Practices to Reduce Substance Use Disorders Through an Integrated Dissemination and Implementation Framework

Major research breakthroughs over the past 30 years in the field of substance use prevention have served to: (1) enhance understanding of pharmacological effects on the central and peripheral nervous systems and the health and social consequences of use of psychoactive substances, particularly for children and adolescents; (2) delineate the processes that increase vulnerability to or protect from initiation of substance use and progression to substance use disorders (SUDs) and, based on this understanding, (3) develop effective strategies and practices to prevent the initiation and escalation of substance use. The challenge we now face as a field is to "normalize" what we have learned from this research so that it is incorporated into the work of those involved in supporting, planning, and delivering prevention programming to populations around the world, is integrated into health and social service systems, and helps to shape public policies. But we wish to go further, to incorporate these effective prevention practices into everyday life and the mind-sets of the public, particularly parents and educators. This paper reviews the advances that have been made in the field of prevention and presents a framework and recommendations to achieve these objectives generated during several meetings of prevention and implementation science researchers sponsored by the International Consortium of Universities for Drug Demand Reduction (ICUDDR) that guides a roadmap to achieve "normalization."

Physical inactivity during adolescence heightens risk for cannabis use disorder in adulthood

The association between physical inactivity and substance use throughout adolescence was prospectively investigated in relation to developing cannabis use disorder (CUD). Physical inactivity and substance use in males (N = 462) and females (N = 178) were measured at 12-14, 16, 19, and 22 years of age in a repeated measures design. A structured diagnostic interview was administered to formulate current CUD diagnosis at 22 years of age. Mixture modeling path analysis evaluated the association between physical inactivity, substance use, and CUD. Males: Slope of physical inactivity increase spanning 12-22 years of age mediates the association between number of parents with substance use disorder (SUD) and rate of increase in substance use frequency (prodrome) which mediates the association between physical inactivity (hypothesized vulnerability) and CUD. Females: Number of SUD parents predicts slope of physical inactivity increase in daughters throughout adolescence which covaries with slope of increasing substance use frequency culminating in CUD. The association between parental SUD load (number of SUD affected parents) and CUD was found to not be mediated by physical inactivity. Rate of increase in physical inactivity during adolescence in males and females is a facet of the vulnerability for CUD. These results have ramifications for prevention considering that numerous cognitive, behavior, and emotion features of CUD vulnerability are attenuated by exercise. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Derivation and assessment of the opioid use disorder severity scale: prediction of health, psychological and social adjustment problems

Background: Severity of substance use disorder (SUD) is typically evaluated by tabulating the number of symptoms. The resulting estimate of disorder severity is, however, biased due to intercorrelations among symptoms and their unequal salience. Objective. Employing item response theory (IRT) methodology, opioid use disorder symptoms were calibrated to derive the Opioid Use Disorder Severity Scale (OUDSS) and assess its predictive ability in men and women separately. Methods: A two-parameter IRT model was utilized to derive the OUDSS from DSM-IV symptoms recorded on the Structured Clinical Interview for DSM-IV (SCID) in 438 men and 429 women who reported at least one lifetime opioid consumption event. The predictive ability of the OUDSS was evaluated using the 10 health, psychological, and social adjustment domains of the revised Drug Use Screening Inventory (DUSI-R) assessed 2 years later. Results: The OUDSS score predicted the severity of problems in all 10 DUSI-R domains in men and women. The OUDSS also predicted the DUSI-R diagnostic cutoff score of overall problem density score in men and women (OR = 2.21 and OR = 4.83, respectively). Withdrawal was the most frequently endorsed symptom in this sample of opioid users. The other symptoms' frequencies, while somewhat lower than withdrawal's, did not differ from it substantially, indicating a similar severity threshold. Conclusions: OUDSS enables dimensional measurement of opioid use severity on an interval scale. The OUDSS and DUSI-R together can identify problem areas requiring prevention or treatment.

Genome-Wide Meta-Analyses of FTND and TTFC Phenotypes

INTRODUCTION

FTND (Fagerstrӧm test for nicotine dependence) and TTFC (time to smoke first cigarette in the morning) are common measures of nicotine dependence (ND). However, genome-wide meta-analysis for these phenotypes has not been reported.

METHODS

Genome-wide meta-analyses for FTND (N = 19,431) and TTFC (N = 18,567) phenotypes were conducted for adult smokers of European ancestry from 14 independent cohorts.

RESULTS

We found that SORBS2 on 4q35 (p = 4.05 × 10-8), BG182718 on 11q22 (p = 1.02 × 10-8), and AA333164 on 14q21 (p = 4.11 × 10-9) were associated with TTFC phenotype. We attempted replication of leading candidates with independent samples (FTND, N = 7010 and TTFC, N = 10 061), however, due to limited power of the replication samples, the replication of these new loci did not reach significance. In gene-based analyses, COPB2 was found associated with FTND phenotype, and TFCP2L1, RELN, and INO80C were associated with TTFC phenotype. In pathway and network analyses, we found that the interconnected interactions among the endocytosis, regulation of actin cytoskeleton, axon guidance, MAPK signaling, and chemokine signaling pathways were involved in ND.

CONCLUSIONS

Our analyses identified several promising candidates for both FTND and TTFC phenotypes, and further verification of these candidates was necessary. Candidates supported by both FTND and TTFC (CHRNA4, THSD7B, RBFOX1, and ZNF804A) were associated with addiction to alcohol, cocaine, and heroin, and were associated with autism and schizophrenia. We also identified novel pathways involved in cigarette smoking. The pathway interactions highlighted the importance of receptor recycling and internalization in ND.

IMPLICATIONS

Understanding the genetic architecture of cigarette smoking and ND is critical to develop effective prevention and treatment. Our study identified novel candidates and biological pathways involved in FTND and TTFC phenotypes, and this will facilitate further investigation of these candidates and pathways.

Forecasting Opioid Use Disorder at 25 Years of Age in 16-Year-Old Adolescents

OBJECTIVE

To evaluate the accuracy of detecting 16-year-old male (n = 465) and female (n = 162) youths who subsequently manifest opioid use disorder (OUD) at 25 years of age. We hypothesized that the combined measures of 2 components of etiology, heritable risk, and substance use, accurately detect youths who develop OUD.

STUDY DESIGN

Heritable risk was measured by the transmissible liability index (TLI). Severity of the prodrome presaging OUD was quantified by the revised Drug Use Screening Inventory containing the consumption frequency index (CFI) documenting substance use events during the past month and the overall problem density (OPD) score indicating co-occurring biopsychosocial problems. Diagnosis of OUD was formulated by a clinical committee based on results of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition in conjunction with medical and social history records.

RESULTS

Bivariate analysis shows that the TLI, CFI, and OPD scores at 16 years of age predict OUD at 25 years. Multivariate modeling indicates that the TLI combined with the CFI predict OUD with 86% accuracy (sensitivity = 87%; specificity = 62%). The TLI and CFI at 16 years of age mediate the association between parental substance use disorder and OUD in offspring at 25 years of age, indicating that these measures respectively evaluate risk and prodrome.

CONCLUSIONS

These results demonstrate the feasibility of identifying youths requiring intervention to prevent OUD.

Analysis of substance use and its outcomes by machine learning: II. Derivation and prediction of the trajectory of substance use severity

BACKGROUND

This longitudinal study explored the utility of machine learning (ML) methodology in predicting the trajectory of severity of substance use from childhood to thirty years of age using a set of psychological and health characteristics.

DESIGN

Boys (N = 494) and girls (N = 206) were recruited using a high-risk paradigm at 10-12 years of age and followed up at 12-14, 16, 19, 22, 25 and 30 years of age.

MEASUREMENTS

At each visit, the subjects were administered a comprehensive battery to measure psychological makeup, health status, substance use and psychiatric disorder, and their overall harmfulness of substance consumption was quantified according to the multidimensional criteria (physical, dependence, and social) developed by Nutt et al. (2007). Next, high- and low- substance use severity trajectories were derived differentially associated with probability of segueing to substance use disorder (SUD). ML methodology was employed to predict trajectory membership.

FINDINGS

The high-severity trajectory group had a higher probability of leading to SUD than the low-severity trajectory (89.0% vs 32.4%; odds ratio = 16.88, p < 0.0001). Thirty psychological and health status items at each of the six visits predict membership in the high- or low-severity trajectory, with 71% accuracy at 10-12 years of age, increasing to 93% at 22 years of age.

CONCLUSION

These findings demonstrate the applicability of the machine learning methodology for detecting membership in a substance use trajectory with high probability of culminating in SUD, potentially informing primary and secondary prevention.

Does the Transmissible Liability Index (TLI) assessed in late childhood predict suicidal symptoms at young adulthood?

OBJECTIVE

Our previous work demonstrated that the Transmissible Liability Index (TLI), an instrument designed as an index of liability for substance use disorder (SUD), is associated with risk of substance use disorder. This longitudinal study assessed whether TLI measured in 10-12-year-olds (late childhood) predicts suicidal behavior from age 12-14 (preadolescence) to age 25 (young adulthood). We hypothesized that TLI would predict number and severity of suicide attempts.

METHODS

Subjects were sons of men who had lifetime history of SUD (n = 250), called the High Average Risk (HAR) group, and sons of men with no lifetime history of a SUD (n = 250), called the Low Average Risk (LAR) group. The TLI was delineated at baseline (age 10-12), and age-specific versions were administered at 12-14, 16, 19, 22, and 25 years of age.

RESULTS

TLI was significantly associated with number and severity of lifetime suicide attempts.

CONCLUSIONS

These findings confirm the hypothesis that TLI assessed at late childhood is a predictor of frequency and severity of suicidal behavior from preadolescence to young adulthood.

Externalizing behavior and emotion dysregulation are indicators of transmissible risk for substance use disorder

BACKGROUND

Psychological items discriminating children of fathers diagnosed with an illicit drug-related substance use disorder and normal controls are indicators of a unidimensional construct termed transmissible liability index (TLI) (Vanyukov et al., 2009). TLI is a highly heritable (Vanyukov et al., 2009; Hicks, Iacono, McGue, 2012) and valid (Vanyukov et al., 2009; Hicks et al., 2009; Kirisci et al., 2013a) measure of childhood liability to substance use disorders (SUDs).

AIMS

This longitudinal study determined whether TLI has incremental validity for predicting SUD beyond commonly measured psychological indicators of risk.

METHODS

TLI and measures of executive cognitive capacity, emotion dysregulation and externalizing disturbance were administered to boys at ages 10-12 and 16. SUD outcome determined at age 22 was assessed as (1) any SUD, (2) the number of drug-specific SUDs, and (3) SUD severity.

RESULTS

TLI predicted SUD beyond the contribution of measures of emotion dysregulation, executive cognitive capacity and externalizing disturbance. The association of emotion dysregulation and externalizing behavior at ages 10-12 and 16 with SUD at age 22 was also reduced to non-significance after controlling for transmissible risk measured by TLI.

CONCLUSIONS

TLI's incremental validity beyond these latter indicators of risk points to its utility for identifying vulnerable youths requiring intervention.

Familiality of addiction and its developmental mechanisms in girls

BACKGROUND

Drug use disorders (DUD) have been theorized to share sources of risk variation with other consummatory behaviors. We hypothesized that common mechanisms exist for familial risk for DUD, physiological maturation and nutritional status in girls. Whereas body fat content must exceed a threshold to enable adrenarche and gonadarche, nutritional status may also be a behavior risk indicator. Impaired psychological self-regulation associated with DUD risk may manifest in early overeating, which could in turn accelerate reproductive maturation, resulting in a greater likelihood of affiliation with deviant/older peers and drug use.

METHOD

The sample consisted of families ascertained through the father who either had (N=95) or did not have (N=130) a DUD, and who had a 10-12 year old daughter and her mother available for study. Correlation, survival and path analyses of three consecutive assessments evaluated the relationships between parental DUD (number of affected parents, NAP), nutritional status (NS, subscapular skinfold measurements and body mass index), sexual maturation (Tanner stage), peer delinquency, and the daughter's lifetime DUD diagnosis.

RESULTS

NAP was positively related to the girls' nutritional status. Longitudinal path analysis indicated mediation of the relationship between NAP and peer delinquency by sexual maturation. The relationship between NAP and sexual maturation is mediated by NS. The effect of sexual maturation at age ∼11 on the girls' DUD risk is mediated by peer delinquency.

CONCLUSION

The data are consistent with mediation of intergenerational transmission of DUD risk in females by elevated nutrition, leading to accelerated maturation, and affiliation with deviant peers.

Longitudinal modeling of transmissible risk in boys who subsequently develop cannabis use disorder

BACKGROUND

Risk for substance use disorder is frequently transmitted across generations due to significant heritability.

OBJECTIVE

This longitudinal study tests the hypothesis that initial exposure to cannabis in youths having high transmissible risk is a signal event promoting development of cannabis use disorder (CUD).

METHODS

At age 22, 412 men were classified into three groups: (1) lifetime CUD, (2) cannabis use without CUD, and (3) no lifetime cannabis use. Transmissible risk, quantified on a continuous scale using the previously validated transmissible liability index (TLI), along with cannabis use and CUD were documented at 10-12, 12-14, 16, 19, and 22 years of age.

RESULTS

The CUD group scored higher on the TLI before they began cannabis use compared to the other two groups. In addition, a progressive increase in TLI severity was evinced by the CUD group beginning at the time of initiation of cannabis use whereas cannabis users who did not subsequently develop CUD exhibited a decline in transmissible risk following first exposure.

CONCLUSION

Initial use of cannabis potentiates development of CUD in youths who are at high transmissible risk but is inconsequential in youths having low risk. The practical ramifications of these results for prevention are discussed.

Age of alcohol and cannabis use onset mediates the association of transmissible risk in childhood and development of alcohol and cannabis disorders: evidence for common liability

Age at the time of first alcohol and cannabis use was investigated in relation to a measure of transmissible (intergenerational) risk for addiction in childhood and development of alcohol use disorder (AUD) and cannabis use disorder (CUD). It was hypothesized that age at the time of first experience with either substance mediates the association between transmissible risk and subsequent diagnosis of both disorders. The Transmissible Liability Index (TLI; (Vanyukov et al., 2009) was administered to 339 10- to 12-year-old boys (n = 254) and girls (n = 85). Age at the time of first alcohol and cannabis use, and diagnosis of AUD and CUD, were prospectively tracked to age 22. Each standard deviation unit increase in TLI severity corresponded to a reduction in age of alcohol and cannabis use onset by 3.2 months and 4.6 months, respectively. Age at the time of first alcohol use mediated the association of TLI with both AUD and CUD. Parallel results were obtained for cannabis. Whereas transmissible risk is congenerous to both AUD and CUD, its magnitude was 7 times greater in youths who initiated substance use with cannabis. TLI predicts age of first use of alcohol and cannabis that is common to developing both AUD and CUD. The ramifications of these findings for prevention are discussed.

Relation among HPA and HPG neuroendocrine systems, transmissible risk and neighborhood quality on development of substance use disorder: results of a 10-year prospective study

BACKGROUND

Research has shown involvement of hormones of the hypothalamic pituitary adrenal (HPA) axis and hypothalamic pituitary gonadal (HPG) axis in the regulation of behaviors that contribute to SUD risk and its intergenerational transmission. Neighborhood environment has also been shown to relate to hormones of these two neuroendocrine systems and behaviors associated with SUD liability. Accordingly, it was hypothesized that (1) parental SUD severity and neighborhood quality correlate with activity of the HPG axis (testosterone level) and HPA axis (cortisol stability), and (2) transmissible risk during childhood mediates these hormone variables on development of SUD measured in adulthood.

METHODS

Transmissible risk for SUD measured by the transmissible liability index (TLI; Vanyukov et al., 2009) along with saliva cortisol and plasma testosterone were prospectively measured in boys at ages 10-12 and 16. Neighborhood quality was measured using a composite score encompassing indicators of residential instability and economic disadvantage. SUD was assessed at age 22.

RESULTS

Neither hormone variable cross-sectionally correlated with transmissible risk measured at ages 10-12 and 16. However, the TLI at age 10-12 predicted testosterone level and cortisol stability at age 16. Moreover, testosterone level, correlated with cortisol stability at age 16, predicted SUD at age 22.

CONCLUSION

HPA and HPG axes activity do not underlie variation in TLI, however, high transmissible risk in childhood predicts neuroendocrine system activity presaging development of SUD.

Computer adaptive testing of liability to addiction: identifying individuals at risk

BACKGROUND

Employed as a quantitative measure of substance use disorder (SUD) risk, the transmissible liability index (TLI) can be useful for detecting youths requiring prevention intervention. This study was conducted to develop and evaluate a computer adaptive test (CAT) version of the TLI to identifying individuals at risk for SUD.

METHODS

In the first sample (N=425) of male and female subjects were recruited under aegis of the Center for Education and Drug Abuse Research in Pittsburgh, PA, USA, having a mean age of 18.8 years. A provisional CAT version of the TLI was assessed using simulation procedures. In sample 2, twins were recruited at the 2010 Twinsburg Festival in Twinsburg, OH, USA. The CAT and paper and pencil (P&P) versions of the TLI were administered to 276 twin pairs having a mean age of 19.94 years.

RESULTS

The simulated CAT version of the TLI predicted cannabis use disorder 2 years after initial study with 4% less accuracy (72% vs. 68%) than P&P version but with 78% reduction of items. In the twin sample, the CAT version predicted alcohol and drug use (OR=1.7 [2.1], p<.001) with 64% and 65% accuracy (sensitivity=75% [75%] and specificity=64% [65%]).

CONCLUSIONS

This study demonstrated that the CAT version of the TLI is an accurate and efficient measure of risk for SUD. The CAT version of the TLI potentially affords the opportunity for efficient screening of risk so that timely interventions can be implemented to prevent occurrence of SUDs having frequently lifelong consequences.

Deviant socialization mediates transmissible and contextual risk on cannabis use disorder development: a prospective study

AIMS

This study examined the contribution of transmissible risk, in conjunction with family and peer contextual factors during childhood and adolescence, on the development of cannabis use disorder in adulthood.

DESIGN

The family high-risk design was used to recruit proband fathers with and without substance use disorder and track their sons longitudinally from late childhood to adulthood.

SETTING

The families were recruited under the aegis of the Center for Education and Drug Abuse Research in Pittsburgh, Pennsylvania.

PARTICIPANTS

The oldest son in the family was studied at ages 10-12, 16, 19 and 22 years.

MEASUREMENTS

The transmissible liability index (TLI), along with measures of quality of the parent-child relationship, cooperative behavior at home, social attitudes and peer milieu were administered to model the developmental pathway to cannabis use disorder.

FINDINGS

Affiliation with socially deviant peers and harboring non-normative attitudes (age 16) mediate the association between transmissible risk for substance use disorder (SUD) (age 10-12) and use of illegal drugs (age 19), leading to cannabis use disorder (age 22).

CONCLUSIONS

Deviant socialization resulting from transmissible risk and poor parent-child relationship is integral to development of cannabis use disorder in young adulthood.

Developing an Institutional Informational Base and Bibliographical Clearinghouse

Successful management and implementation of the diverse functions of the International Network of Person-Centered Medicine (INPCM) require a comprehensive and efficient informational base to advance quality of patient care though timely and rapid distribution of knowledge via publications, conferences, and education programs in concert with catalyzing research through systematic efficient data acquisition, storage, retrieval, and analysis. This study describes the structure and functions of the proposed INPCM's information system.

Measuring addiction propensity and severity: the need for a new instrument

Drug addiction research requires but lacks a valid and reliable way to measure both the risk (propensity) to develop addiction and the severity of manifest addiction. This paper argues for a new measurement approach and instrument to quantify propensity to and severity of addiction, based on the testable assumption that these constructs can be mapped onto the same dimension of liability to addiction. The case for this new direction becomes clear from a critical review of empirical data and the current instrumentation. The many assessment instruments in use today have proven utility, reliability, and validity, but they are of limited use for evaluating individual differences in propensity and severity. The conceptual and methodological shortcomings of instruments currently used in research and clinical practice can be overcome through the use of new technologies to develop a reliable, valid, and standardized assessment instrument(s) to measure and distinguish individual variations in expression of the underlying latent trait(s) that comprises propensity to and severity of drug addiction. Such instrumentation would enhance our capacity for drug addiction research on linkages and interactions among familial, genetic, psychosocial, and neurobiological factors associated with variations in propensity and severity. It would lead to new opportunities in substance abuse prevention, treatment, and services research, as well as in interventions and implementation science for drug addiction.

Neurobehavior disinhibition, parental substance use disorder, neighborhood quality and development of cannabis use disorder in boys

This prospective investigation examined the contribution of neighborhood context and neurobehavior disinhibition to the association between substance use disorder (SUD) in parents and cannabis use disorder in their sons. It was hypothesized that both neighborhood context and son's neurobehavior disinhibition mediate this association. Two hundred and sixteen boys were tracked from ages 10-12 to age 22. The extent to which neighborhood context and neurobehavior disinhibition mediate the association between parental SUD and son's cannabis use disorder was evaluated using structural equation modeling. The best fitting model positioned neighborhood context and neurobehavior disinhibition as mediators of the association between parental SUD and cannabis use disorder in sons. Neurobehavior disinhibition also was a mediator of the association between neighborhood context and son's cannabis use. The implications of this pattern of association between parental SUD, neighborhood context and individual risk for SUD for improving prevention are discussed.

Prediction of cannabis use disorder between boyhood and young adulthood: clarifying the phenotype and environtype

Employing a prospective paradigm, this investigation derived the childhood phenotype and the environtype associated with risk for cannabis use disorder. Two hundred and sixteen boys were evaluated between age 10-12 on a comprehensive protocol using self, mother, and teacher reports and followed-up at ages 19 and 22 to determine the presence of cannabis use disorder. The Transmissible Liability Index (TLI) and Non-Transmissible Liability Index (NTLI) were derived using item response theory. Logistic regression was conducted to evaluate the accuracy of the indexes, singly and in combination, to predict cannabis use disorder. The TLI and NTLI together predicted with 70% and 75% accuracy cannabis use disorder manifest by age 19 and age 22. Sensitivity was 75% at both ages 19 and 22, whereas specificity was respectively 51% and 64%. The findings pertaining to sensitivity indicate that SUD risk for cannabis use disorder can be screened in childhood; however, the specificity scores demonstrate that a low score on the TLI does not inevitably portend a good prognosis up to 10 years later.

Prospective study of the association between abandoned dwellings and testosterone level on the development of behaviors leading to cannabis use disorder in boys

BACKGROUND

The role of testosterone in the development of behaviors presaging cannabis use and subsequently cannabis use disorder was investigated in a prospective study of 208 boys. It was theorized that adverse neighborhood correlates with testosterone level that in turn potentiates behaviors predisposing to cannabis consumption and subsequently diagnosis of cannabis use disorder.

METHODS

Proportion of boarded-up dwellings in the 1990 census tract and testosterone level were recorded at baseline (ages 10-12), followed by assessments of assaultiveness and testosterone level (ages 12-14), social dominance/norm-violating behavior (SDNVB) (age 16), cannabis use (age 19), and cannabis use disorder (age 22).

RESULTS

Percent of vacant dwellings correlates with testosterone level that in turn predicts assaultive behavior sequentially leading to SDNVB, cannabis use, and cannabis use disorder. Externalizing behaviors and cannabis use disorder are not directly predicted by neighborhood quality.

CONCLUSIONS

Elevated testosterone level intermediates the association between neighborhood adversity and aggressive socially deviant behaviors presaging cannabis use and cannabis use disorder.

Modeling the pathways linking childhood hyperactivity and substance use disorder in young adulthood

This study modeled direct and mediated pathways linking childhood hyperactivity and substance use disorder (SUD). Boys (n = 112) were administered the revised Drug Use Screening Inventory at age 12-14 years and the Structured Clinical Interview for DSM-IV at age 22 years. Six newly derived scales having established heritability were conceptually organized into internalizing and externalizing pathways to SUD emanating from childhood hyperactivity. Hyperactivity directly predicts SUD. Neuroticism, conduct problems, and their respective manifestations of social withdrawal and school problems mediated the association between hyperactivity and SUD. Hyperactivity also predicted neuroticism that, in turn, predicted low self-esteem leading to social withdrawal and SUD. These results indicate that hyperactivity is a diathesis for both internalizing and externalizing disturbances that, in turn, portend differential expression of psychosocial maladjustment presaging SUD.

Developmental trajectory classes in substance use disorder etiology

Three trajectory classes culminating in substance use disorder (SUD) were discerned in a longitudinal study of boys from ages 10-12 to 22 years. Neurobehavior disinhibition, parental SUD, socioeconomic status, and affiliation with deviant peers were measured at baseline. Approval of socially nonnormative behavior was measured at ages 10-12, 12-14, 16, and 19 years. Two high-risk trajectories, indicated by increasing approval of antisociality and progressive social maladjustment during adolescence (SUD rate = 72.7%) and stable high level of disturbance (SUD rate = 85%), were identified. Individual characteristics (neurobehavior disinhibition) in conjunction with contextual factors (low socioeconomic status, parental SUD, affiliation with deviant friends) promote approval of antisociality during adolescence and a high rate of SUD by young adulthood.

Predictors of marijuana use in adolescents before and after licit drug use: examination of the gateway hypothesis

OBJECTIVE

The authors investigated whether the transition from licit drug use to marijuana use is determined by particular risk factors, as specified by the gateway hypothesis. They also evaluated the accuracy of the "gateway sequence" (illicit drug use following licit drugs) for predicting a diagnosis of substance use disorder.

METHOD

Boys who consumed licit drugs only (N=99), boys who consumed licit drugs and then transitioned to marijuana use (gateway sequence) (N=97), and boys who used marijuana before using licit substances (alternative sequence) (N=28) were prospectively studied from ages 10-12 years through 22 years to determine whether specific factors were associated with each drug use pattern. The groups were compared on 35 variables measuring psychological, family, peer, school, and neighborhood characteristics. In addition, the utility of the gateway and alternative sequences in predicting substance use disorder was compared to assess their clinical informativeness.

RESULTS

Twenty-eight (22.4%) of the participants who used marijuana did not exhibit the gateway sequence, thereby demonstrating that this pattern is not invariant in drug-using youths. Among youths who did exhibit the gateway pattern, only delinquency was more strongly related to marijuana use than licit drug use. Specific risk factors associated with transition from licit to illicit drugs were not revealed. The alternative sequence had the same accuracy for predicting substance use disorder as the gateway sequence.

CONCLUSIONS

Proneness to deviancy and drug availability in the neighborhood promote marijuana use. These findings support the common liability model of substance use behavior and substance use disorder.

Application of item response theory to quantify substance use disorder severity

OBJECTIVE

The present investigation had two main goals: (1) Determine whether binary substance use disorder (SUD) diagnoses are indicators of a unidimensional trait indexing severity of disorder; and, (2) demonstrate the predictive, concurrent and construct validity of the SUD severity scale.

METHODS

Boys and their biological parents were administered structured diagnostic interviews to diagnose SUD. Item response theory (IRT) was applied to determine whether the diagnoses are indicators of a unidimensional trait. The score on this scale was correlated with substance use behavior, violence, treatment history, risky sex, and social adjustment.

RESULTS

SUD diagnoses are indicators of a unidimensional latent trait. Maternal and paternal SUD severity predicted son's SUD severity at age 19. The score on the SUD severity scale correlated with drug use frequency, number of different drugs used in lifetime, treatment seeking, illegal behavior, social maladjustment, and risky sex.

CONCLUSION

SUD can be quantified on an interval scale indexing severity of disorder. The advantages of measuring SUD severity as a continuous trait are discussed.

Individual differences in childhood neurobehavior disinhibition predict decision to desist substance use during adolescence and substance use disorder in young adulthood: a prospective study

Genetic, physiological and psychological investigations have demonstrated that deficient inhibitory regulation amplifies the risk for substance use disorder (SUD). This study extends this line of research by determining the association between childhood neurobehavior disinhibition and decision to desist substance use following prevention intervention during adolescence. The sample consisted of 302 boys who were evaluated at ages 10-12, 12-14, 16, and 19. Results indicated that childhood neurobehavior disinhibition negatively covaried with decision to desist substance use during adolescence. These two variables predicted acceleration of drug consumption frequency during adolescence and DSM-IV diagnosis of SUD by age 19. Decision to desist drug use did not mediate the association between neurobehavior disinhibition and substance use/SUD. The findings indicate that substance abuse prevention would be potentiated by ameliorating childhood neurobehavior disinhibition.

Detection of youth at high risk for substance use disorders: a longitudinal study

This study extends prior research (D. Clark, J. Cornelius, L. Kirisci, & R. Tarter, 2005) by determining whether variation in the developmental trajectories of liability to substance use disorder (SUD) is contributed by neurobehavioral disinhibition, parental substance use involvement, and demographic variables. The sample, participants in a long-term prospective investigation, consisted of 351 boys, evaluated at ages 10-12, 12-14, 16, 19, and 22, whose parents either had SUD or no adult psychiatric disorder. Neurobehavioral disinhibition in childhood, in conjunction with parental lifetime substance use/SUD, place the child at very high risk for SUD by age 22 if psychosocial maladjustment progresses in severity in early adolescence. These results indicate that monitoring social adjustment during the transition from childhood to mid-adolescence is important for identifying youth at very high risk for succumbing to SUD by young adulthood.

Mutans streptococci in preschool twins

OBJECTIVE

The purpose of this study was to determine whether genetic factors influence variation in salivary levels of the mutans streptococci (MS) in preschool twins.

DESIGN

The study population consisted of 48 pairs of monozygotic (MZ) twins and 54 pairs of dizygotic (DZ) twins. Genotyping eight highly polymorphic DNA markers determined zygosity. Demographic data and antibiotic exposure as reported by mothers were obtained by a face-to-face interview. Salivary levels of MS were determined by the Stripmutanstrade mark test. Test results are reported on a scale of 0-3. Regression analysis, two sample t-tests and structural equation modeling were applied to analyse the data.

RESULTS

Only 6% of the participants ever visited a dentist (F component of the DMFS was 0 for this population). Average salivary scores for the mutans streptococci were significantly different between MZ (1.1+/-0.1) and DZ (0.8+/-0.1) twins (p=0.021). High salivary levels of MS (scores 2 and 3) were observed in 42% of MZ twins and in 26% of DZ twins. Regression analysis on the MS salivary levels revealed no significant effects of age, gender and antibiotic intake for MZ or DZ twins. The heritability of mutans streptococci colonisation in 48 pairs MZ and in 26 pairs of DZ twins was estimated to be 52%. The non-shared environment contribution was estimated to be 48%.

CONCLUSIONS

These results suggest that variation in the salivary levels of the mutans streptococci is significantly contributed by genetic factors.

Relation between cognitive distortions and neurobehavior disinhibition on the development of substance use during adolescence and substance use disorder by young adulthood: a prospective study

OBJECTIVE

Previous research has demonstrated that neurobehavior disinhibition increases the risk for a diagnosis of substance use disorder (SUD). This investigation tested the hypothesis that a deficiency in the capacity to appraise the effects of alcohol and drugs and interpret social interactions mediates the relation between neurobehavior disinhibition in childhood and SUD by early adulthood.

METHODS

Boys with fathers having lifetime SUD (N=88) and no SUD or other psychiatric disorder (N=127) were prospectively tracked from ages 10-12 to 19 years. Neurobehavior disinhibition was evaluated at baseline followed by assessments of cognitive distortions and substance use involvement in early and mid-adolescence. SUD outcome was evaluated up to age 19 years.

RESULTS

Cognitive distortions (age 12-14 years) mediated the association between neurobehavior disinhibition (age 10-12 years) and marijuana use (age 16 years) which, in turn, predicted SUD by age 19 years. Cognitive distortions in early adolescence did not directly predict SUD by young adulthood.

CONCLUSIONS

Inaccurate social cognition, significantly predicted by childhood neurobehavior disinhibition, biases development toward marijuana use prodromal to SUD. These results indicate that cognitive processes, in conjunction with psychological self-regulation, comprise important components of the individual liability to SUD.

Psychopathology risk transmission in children of parents with substance use disorders

OBJECTIVE

Children of fathers with substance use disorders are at increased risk for psychopathology, including conduct disorder, attention deficit hyperactivity disorder (ADHD), major depressive disorder, and anxiety disorders. This study examined the distinct influences of parent substance use disorder and other psychopathology in the transmission of the risk for psychopathology to their children.

METHOD

The subjects were 1,167 children (ages 6-14 years; 62% were male, 38% were female) from 613 families recruited according to a high-risk paradigm. Of these families, 294 had fathers with a substance use disorder (high-risk group), and 319 had fathers without a substance use disorder or other mental disorder (low-risk group). In all families, father, mother, and children were directly assessed. Mixed-effects ordinal regression analyses controlled for the nested data structure.

RESULTS

For conduct disorder, ADHD, major depression, and anxiety disorders, the results indicated that the predominant predictor of specific mental disorders in offspring was a history of the corresponding disorders in both parents.

CONCLUSIONS

These results support specific parent-child transmission for childhood psychopathology.

Neurobehavior disinhibition in childhood predisposes boys to substance use disorder by young adulthood: direct and mediated etiologic pathways

OBJECTIVE

The development of substance use disorder (SUD) was prospectively investigated in 66 boys having fathers with SUD and 104 boys having fathers with no adult Axis I or II psychiatric disorder. Evaluations were conducted to determine the context in which neurobehavior disinhibition in relation to parental SUD, parental neglect of the child and child's social maladjustment culminated in a DSM-III-R diagnosis of SUD.

METHODS

A neurobehavior disinhibition latent trait was derived using indicators of behavior undercontrol, affect dysregulation and executive cognitive functioning in the boys when they were 10-12 and again at 16 years of age. These latter characteristics have been frequently observed in individuals who have a prefrontal cortex disturbance. The data were analyzed to determine whether the score on the neurobehavior disinhibition construct mediates the association between father's and mother's SUD and son's SUD.

RESULTS

SUD in the mother and father predicted neurobehavior disinhibition in the son. The neurobehavior disinhibition score in the sons predicted SUD between ages 10-12 and 19. Neurobehavior disinhibition, in conjunction with social maladjustment and drug use frequency, mediated the association between paternal and maternal SUD and son's SUD. Neurobehavior disinhibition was unrelated to neglect of the child by either the father or mother; however, paternal but not maternal neglect at age 10-12 predicted SUD at age 19.

CONCLUSIONS

The association of neurobehavior disinhibition in childhood and SUD by young adulthood suggests that a prefrontal cortex dysfunction contributes to SUD liability. The results extend previous findings demonstrating that neurobehavior disinhibition is an important component of the liability to SUD.

Neurobehavioral disinhibition in childhood predicts early age at onset of substance use disorder

OBJECTIVE

This longitudinal study had three aims: 1) determine the extent to which boys at high average risk and low average risk for substance use disorder differ on a construct of neurobehavioral disinhibition, 2) evaluate the capacity of neurobehavioral disinhibition to predict substance use frequency at age 16, and 3) demonstrate the utility of neurobehavioral disinhibition in predicting substance use disorder.

METHOD

The authors derived an index of neurobehavioral disinhibition from measures of affect, behavior, and cognition. The neurobehavioral disinhibition score was used to discriminate youth at high and low average risk for substance use disorder and to predict substance use frequency after 4-6 years and substance use disorder after 7-9 years.

RESULTS

The neurobehavioral disorder score significantly discriminated boys at high average risk from those at low average risk at ages 10-12. Neurobehavioral disinhibition at age 16, in conjunction with substance use frequency and risk status group, predicted substance use disorder at age 19 with 85% accuracy and accounted for 50% of the variance in Drug Use Screening Inventory overall problem density score. Neurobehavioral disinhibition was a stronger predictor of substance use disorder (odds ratio=6.83) than substance consumption frequency (odds ratio=3.19).

CONCLUSIONS

Cross-sectional and longitudinal analyses indicated that neurobehavioral disinhibition is a component of the liability to early age at onset of substance use disorder.

Item response theory modeling of substance use: an index based on 10 drug categories

This study examined the psychometric characteristics of an index of substance use involvement using item response theory. The sample consisted of 292 men and 140 women who qualified for a Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) substance use disorder (SUD) diagnosis and 293 men and 445 women who did not qualify for a SUD diagnosis. The results indicated that men had a higher probability of endorsing substance use compared with women. The index significantly predicted health, psychiatric, and psychosocial disturbances as well as level of substance use behavior and severity of SUD after a 2-year follow-up. Finally, this index is a reliable and useful prognostic indicator of the risk for SUD and the medical and psychosocial sequelae of drug consumption.

Pittsburgh Registry of Infant Multiplets (PRIM)

This paper describes the Pittsburgh Registry of Infant Multiplets (PRIM; Pittsburgh, Pennsylvania), the results of pilot research conducted in this registry, and the plans for future studies. The main focus of the registry is on psychological development and the risk for behavioral disorders. Particularly, characteristics associated with antisociality and the risk for substance use disorders (e.g., aggressivity, hyperactivity/impulsivity), as well as language development and other traits (e.g., dental health) are among the research targets.

Predicting adolescent violence: impact of family history, substance use, psychiatric history, and social adjustment

OBJECTIVE

The aim of this study was to provisionally develop an efficient screening method to detect adolescents at high risk for committing a violent act by young adulthood. In addition, the authors sought to use this screening instrument, in conjunction with child and parent psychopathology and substance abuse data, to determine the accuracy of violent outcome predictions.

METHOD

The probands were men with a lifetime history of DSM-III-R substance use disorder (N=38) and men with no adult psychiatric disorder (N=61). Their biological sons were studied at two time points. At age 12-14, the offspring completed a 13-item Violence Proneness Scale, which was derived by using items from the revised Drug Use Screening Inventory. The occurrence of violent acts was then assessed at a follow-up evaluation when the offspring were 19 years of age.

RESULTS

Among the offspring, a DSM-III-R axis I psychiatric disorder and a Violence Proneness Scale score of 10 or higher at age 12-14 predicted a violent outcome by age 19. The overall accuracy of prediction was 77%. Sensitivity was 81%, and specificity was 76%. Substance use disorder or psychopathology in the probands or substance use frequency in the children did not contribute to the prediction of violence.

CONCLUSIONS

The brief Violence Proneness Scale, which measures school and peer adjustment, in conjunction with a childhood psychiatric history may constitute an efficient screening procedure for identifying youth who are at high risk for committing acts of violence.

Origins and consequences of child neglect in substance abuse families

The empirical literature pertaining to the prevalence, origins, and consequences of neglectful parenting as it relates to substance abuse is critically reviewed. Available evidence indicates that children who experience parental neglect, with or without parental alcohol or drug abuse, are at high risk for substance use disorder (SUD). The effects of parental substance abuse on substance abuse outcome of their children appear to be partly mediated by their neglectful parenting. The discussion concludes with presentation of a developmental multifactorial model in which neglect, in conjunction with other individual and environmental factors, can be integratively investigated to quantify the child's overall liability across successive stages of development as well as to map the trajectory toward good and poor outcomes.

Etiology of early age onset substance use disorder: a maturational perspective

The etiology of early age onset substance use disorder (SUD), an Axis I psychiatric illness, is examined from the perspective of the multifactorial model of complex disorders. Beginning at conception, genetic and environment interactions produce a sequence of biobehavioral phenotypes during development which bias the ontogenetic pathway toward SUD. One pathway to SUD is theorized to emanate from a deviation in somatic and neurological maturation, which, in the context of adverse environments, predisposes to affective and behavioral dysregulation as the cardinal SUD liability-contributing phenotype. Dysregulation progresses via epigenesis from difficult temperament in infancy to conduct problems in childhood to substance use by early adolescence and to severe SUD by young adulthood.

Salivary cortisol responses in prepubertal boys: the effects of parental substance abuse and association with drug use behavior during adolescence

BACKGROUND

The purpose of this investigation was three-fold. First, we extended our original observation of decreased cortisol reactivity to an anticipated stressor in sons of fathers with a substance use disorder (SUD). Second, we examined the hypothesis that salivary cortisol underresponsivity in these high-risk prepubertal boys is an adaptation to the stress associated with having a father with a current, rather than remitted, SUD. Third, we tested the hypothesis that prepubertal cortisol underreactivity might be associated with subsequent drug use behavior during adolescence.

METHODS

Preadolescent salivary cortisol responses were examined in the context of risk-group status, paternal substance abuse offsets, and subsequent adolescent drug use behavior.

RESULTS

The results confirmed a decreased salivary cortisol response to an anticipated stressor among sons of SUD fathers in our expanded sample. In addition, sons of fathers with a current SUD and boys whose fathers had a SUD offset from their 3rd to 6th birthdays had lower anticipatory stress cortisol levels compared with sons of control fathers. Finally, lower preadolescent anticipatory cortisol responses were associated with regular monthly cigarette smoking and regular monthly marijuana use during adolescence.

CONCLUSIONS

Hyporeactivity as an adaptation to chronic stress may be salient to the intergenerational transmission of substance abuse liability.

Prepubertal sons of substance abusers: influences of parental and familial substance abuse on behavioral disposition, IQ, and school achievement

In order to better understand the transgeneration liability for a substance abuse disorder, we investigated the impact of parental and familial substance abuse disorders on prepubertal boys. Specifically, the influence of each parent's substance abuse history and the effects of significant family aggregation of substance abuse disorders were tested as predictors of the child's behavioral disposition, IQ, and school achievement scores, while controlling for socioeconomic status (SES). Sons of substance abusing fathers were found to have higher externalizing and internalizing problem-behavior scores, lower IQ scores, and lower school achievement scores. Internalizing and externalizing problem-behavior scores were most strongly associated with bilineal parental substance abuse, whereas SES and paternal substance abuse were most strongly associated with IQ and school performance scores. The results are compatible with the hypothesis that although paternal substance abuse has an adverse impact on the son's functioning, bilineal parental substance abuse is associated with the greatest behavioral deviancy among prepubertal males and is associated with a greater liability for substance abuse.

Alcoholism: a developmental disorder

Alcoholism etiology is discussed from a developmental behavior genetic perspective. At the outset point, temperament characteristics, by means of ongoing and reciprocal interaction with the social environment, shape the course of behavioral development. The behavioral characteristics successively acquired during development are vectors that determine the ontogenetic trajectory that culminates ultimately in the clinical disorder of alcoholism. The temperament features that appear to be associated with a heightened risk for alcoholism are examined. Their interactions with the environment during the course of development are considered within an epigenetic framework and, as discussed, have important ramification for improving the prevention and treatment of alcoholism.

Alcoholism: a developmental disorder

Alcoholism etiology is discussed from a developmental behavior genetic perspective. At the outset point, temperament characteristics, by means of ongoing and reciprocal interaction with the social environment, shape the course of behavioral development. The behavioral characteristics successively acquired during development are vectors that determine the ontogenetic trajectory that culminates ultimately in the clinical disorder of alcoholism. The temperament features that appear to be associated with a heightened risk for alcoholism are examined. Their interactions with the environment during the course of development are considered within an epigenetic framework and, as discussed, have important ramification for improving the prevention and treatment of alcoholism.

Familial resemblance for psychoactive substance use disorders: behavioral profile of high risk boys

Familial transmission plays an etiologically important role in psychoactive substance use disorders (PSUD). The delineation of the risk status of families is central to implementation of the "high risk paradigm" in studying liability characteristics for PSUD. We have utilized a latent variable approach to characterizing familial resemblance for PSUD which incorporates elements of both the affected parent design, as well as a genetic epidemiologic indicator of familial aggregation of disease. Family resemblance scores were computed for 175 families in which fathers either met diagnostic criteria for PSUD or did not. We then compared the problem behavior profiles of 10-12 year-old boys grouped by familial resemblance for PSUD, and by paternal PSUD only. Boys grouped by paternal PSUD only had higher problem behavior scores than controls across all scales except for somatic complaints. Boys from families that have significant PSUD familial resemblance were characterized by higher scores on measures of externalizing conduct and socialization problems. Thus, the familial resemblance approach was more specific for the externalizing problem behaviors that have been described in longitudinal studies of childhood risk factors for later substance abuse.

Heterogeneity of adolescent alcoholism

Adolescent alcoholics in treatment were classified into two broad clusters. The larger group consisted of youth who demonstrated behavioral dyscontrol and hypophoria, whereas the smaller group consisted of individuals with primarily negative affect. These two clusters differed with respect to age of first drug use, age of first substance abuse diagnosis, severity of substance use, behavior disturbance, and psychiatric disorder. Difficult temperament loaded on the negative affect factor. In a second study, it was observed that difficult childhood temperament led to a number of different first diagnoses in the adolescents. No specific psychiatric outcome followed a difficult temperament. These results illustrate the heterogeneity of the adolescent alcoholic population and suggest that there are many developmental pathways to this outcome where a predisposing risk factor is a difficult temperament makeup.