Comorbidity between patterns of substance use dependence and psychiatric syndromes.

BACKGROUND: Comorbidity of dependence on single and multiple drugs with psychiatric syndromes was examined in national samples from the National Household Survey on Drug Abuse (NHSDA). METHODS: Subjects are adults from the l994, l995 and l996 NHSDA surveys. Proxy measures of drug dependence in the last year were constructed from five dependence symptoms that approximated DSM-IV criteria. Measures of patterns of concurrent dependence on cigarettes, alcohol and illicit drugs were constructed. Fallible indicators of a major depressive episode and any anxiety disorder (generalized anxiety disorder, agoraphobia and panic attack) were based on scales measuring symptoms during the last year. Comorbidity was estimated by adjusted odds ratios. RESULTS: Probable drug dependent individuals have higher rates of psychiatric syndromes. Rates of psychiatric syndromes were similar for those uniquely dependent on alcohol, cigarettes or illicit drugs (adjusted odds ratios approximately 2.0). Rates almost doubled for those dependent on both an illicit and a licit drug. CONCLUSIONS: Individuals uniquely dependent on a single drug class experience similar rates of psychiatric morbidity. All those dependent on illicit drugs experience higher rates of psychiatric syndromes. This reflects the additive association of dependence on legal and illegal drugs with psychiatric disorders and the increased rates of dependence on a legal drug among those dependent on an illicit drug. Individuals with multiple dependencies on legal and illegal drugs have the highest need for mental health services.

Extent of smoking and nicotine dependence in the United States: 1991-1993.

Rates of nicotine dependence vary in different sociodemographic groups in the population. These group differences remain to be understood. The objective of this study is to specify the relationship between cigarette consumption and nicotine dependence and whether group differences are explained by quantity smoked or differential sensitivity to nicotine. The data used derived from National Household Surveys on Drug Abuse (1991-1993), multistage area probability samples of the US population 12 years old and over, and anonymous structured household interviews, considering subjects who were last-month smokers (12,550 White, 4903 Black, 4839 Hispanic). The main outcome measure was last-year nicotine dependence based on symptoms of dependence and drug-related problems approximating DSM-IV dependence criteria. Rates are higher among females than males, Whites than minorities and the lowest among older adults. Dependence rates increase sharply up to half a pack of cigarettes smoked per day. At higher quantities, the increased risk for dependence is minimal. The higher rate of dependence among females than males results from a greater number of symptoms at the same quantity smoked. The similarity of adolescent and middle-adult rates results from the fact that adolescents smoke significantly fewer cigarettes than adults, but experience higher rates of dependence at the same levels of use. Although adults 50 and over are the heaviest smokers, they experience the lowest rates of dependence because of hypothesized lower sensitivity to increased quantity of nicotine intake. The higher rates among Whites than Blacks appear to result from heavier smoking and greater sensitivity to nicotine effects. It was concluded that adolescents, women and Whites are particularly vulnerable to becoming dependent on nicotine. Group-specific thresholds may be more appropriate criteria than an absolute threshold to define the risk for nicotine dependence.

Types of marijuana users by longitudinal course.

OBJECTIVE: Taxonomies of alcoholism and antisocial behaviors based on developmental course converge on two-group classifications that emphasize early and late onset. Typologies for users of illicit drugs remain to be developed. This article proposes a developmental taxonomy of marijuana users. METHOD: Cluster analysis was applied to a representative community sample of 708 (364 male, 344 female) marijuana users followed from adolescence to age 34-35. The Ward method, followed by relocation, was used to classify marijuana users into different types based on age of onset, chronicity of heavy use and persistence of use. ANOVA and logit analyses were utilized to describe the cluster solution and examine the correlates of cluster membership. RESULTS: Four marijuana use clusters were identified: early onset-heavy use, early onset-light use, mid onset-heavy use and late onset-light use. The groups differed from each other in degree of involvement in marijuana and other drugs, sociodemographic and lifestyle characteristics. The majority of those with early onset did not become heavily involved in marijuana. Unique factors were associated with membership in each group. Factors differentiating early from mid-onset heavy use included association with marijuana-using peers and having had a mental disorder. Peer delinquency was an additional factor differentiating early initiators who became heavy users from those who did not. CONCLUSIONS: A simple two-type classification fails to take into account the heterogeneity of early and late onset groups. By itself, early onset into marijuana will not lead to problematic use or rapid progression into the use of other drugs. Motivation underlying use and dysfunctional behaviors are associated with the development of problematic drug use and dependence.

Prenatal effects of maternal smoking on daughters' smoking: nicotine or testosterone exposure?

OBJECTIVES: The purpose of this study was to specify the effect of prenatal fetal exposure to maternal cotinine and testosterone on daughters' smoking in adolescence and adulthood. METHODS: Longitudinal causal models were estimated among 240 White mother-daughter pairs from the Child Health and Development Study. Mothers and daughters were reinterviewed when daughters were aged 15 to 17 years, and daughters were interviewed at 27 to 30 years of age. Blood samples were obtained from both parents during pregnancy and from adult daughters. RESULTS: Testosterone and smoking were positively correlated among mothers during their pregnancy and among adult daughters. Maternal prenatal cotinine had no direct effect on daughters' smoking; self-reported smoking in pregnancy did have a direct effect. Smoking among daughters during adolescence was determined by maternal prenatal testosterone and self-reported maternal smoking during pregnancy and postnatally. Smoking among adult daughters reflected chronic smoking since adolescence and the continuing effect of postnatal maternal smoking. Prenatal maternal testosterone affected adult daughters' testosterone. CONCLUSIONS: Estimates of the impact of prenatal maternal smoking depend on the measure of smoking. Prenatal testosterone exposure is a previously unrecognized risk factor for smoking among female offspring.

Maternal smoking during pregnancy and psychopathology in offspring followed to adulthood.

OBJECTIVE: To extend findings from several independent reports of an association between maternal smoking during pregnancy and attention-deficit hyperactivity disorder, conduct disorder, and substance abuse in the offspring. METHOD: This is a 10-year longitudinal study of offspring assessed at 3 points in time into adulthood. Fifty offspring of mothers who reported smoking at least 10 cigarettes almost daily during pregnancy and 97 offspring of mothers who reported never smoking during pregnancy were studied. Psychiatric diagnosis in offspring was assessed blind to parental diagnosis. RESULTS: There was a greater than 4-fold increased risk of prepubertal-onset conduct disorder in boys and a greater than 5-fold increased risk of adolescent-onset drug dependence in girls whose mothers smoked 10 or more cigarettes almost daily during pregnancy. These findings could not be explained by maternal substance abuse during pregnancy, parental psychiatric diagnosis, family risk factors, prenatal and early developmental history of offspring, postnatal maternal smoking, or smoking in the offspring. CONCLUSIONS: Maternal smoking during pregnancy may have a long-term effect on specific psychopathology in offspring. The underlying pathophysiology of nicotine on the fetus requires study. The findings suggest the importance of programs aimed at smoking prevention and cessation in women during pregnancy.

Psychiatric comorbidity among adolescents with substance use disorders: findings from the MECA Study.

OBJECTIVE: To investigate the extent to which adolescents in the community with current substance use disorders (SUD) experience co-occurring psychiatric disorders. METHOD: Diagnostic data were obtained from probability samples of 401 children and adolescents, aged 14 to 17 years, and their mothers/caretakers, who participated in the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study. RESULTS: The rates of mood and disruptive behavior disorders are much higher among adolescents with current SUD than among adolescents without SUD. Comparison with adult samples suggests that the rates of current comorbidity of SUD with psychiatric disorders are the same among adolescents as adults, and lower for lifetime disruptive disorders/antisocial personality disorder among adolescents than adults. CONCLUSIONS: The high rate of coexisting psychiatric disorders among adolescents with SUD in the community needs to be taken into account in prevention and treatment programs.

Ethnic differences in correlates of adolescent cigarette smoking.

PURPOSE: To examine the correlates of cigarette smoking among African-American, Hispanic, and white adolescents in a cross-sectional national sample. METHODS: A total of 1795 mother-child dyads from the 1992 National Longitudinal Survey of Youth were selected for analyses. Measures of adolescents cigarette smoking and family, individual, peer, and sociodemographic risk factors were analyzed. RESULTS: White youths reported the highest rates of lifetime, current, and persistent smoking, and initiated smoking at a significantly earlier age than African-Americans and Hispanics. Except for maternal cigarette smoking and substance use, African-Americans and Hispanics experienced a disproportionately larger number of purported risk factors than whites. Multivariate analyses revealed common and ethnic-specific correlates of adolescent lifetime and current smoking, with many more significant associations among whites than minorities. Common correlates included youth's age across all three ethnic groups, problem behaviors and delinquency among whites and African-Americans, and perceived peer pressure to smoke among whites and Hispanics. Ethnic-specific correlates included maternal smoking, maternal cocaine use, low maternal religiosity, and negative scholastic attitudes, which increased smoking for whites; and positive parenting, which reduced smoking for African-Americans. CONCLUSIONS: The lack of effects of maternal smoking and perceived peer pressure to smoke on African-American adolescents compared with whites suggests that role modeling and interpersonal influence may be more important determinants of smoking for white than African-American adolescents. The differential impact of family and peer factors on the smoking of adolescents of different ethnicity warrants further investigation.

Predictors of cessation of marijuana use: an event history analysis.

Event history analysis was applied to monthly life and drug histories of a representative community sample of 706 marijuana users, followed from ages 15-16 to 34-35, to investigate factors associated with cessation of marijuana use from adolescence to adulthood. In addition to age and gender, the most important determinants of cessation are the phenomenology of marijuana use, social role participation, depressive symptoms and deviance. Frequent users, those who started using early and those who use illicit drugs other than marijuana are more likely to continue their marijuana use. Using marijuana for social reasons accelerates cessation, using to change one's mood reduces cessation. Becoming pregnant and a parent is the most important social role leading to marijuana cessation for women. There is also a very important experimental effect of the interview itself on the reported timing of a cessation. The effect of a social context favorable to marijuana use appears to reflect selection rather than social influence.

The impact of maternal drinking during and after pregnancy on the drinking of adolescent offspring.

OBJECTIVE: The impact of prenatal maternal drinking on alcohol consumption in adolescent offspring was examined among boys and girls separately. METHOD: A prospective longitudinal sample of 185 mother-firstborn child dyads was used to examine the impact of maternal self-reported alcohol consumption during pregnancy on adolescent self-reported lifetime and current drinking, controlling for potential confounding factors. RESULTS: In this representative general population sample, maternal drinking during pregnancy, particularly continuous moderate to heavy consumption, had a significant positive effect on adolescent daughters' current drinking, but a slight negative effect on sons' lifetime drinking. The sex-specific prenatal effect on current drinking persisted with controls for prenatal maternal cigarette smoking, current maternal drinking, child-rearing practices (i.e., maternal-child closeness, monitoring and a rule against drinking) and the adolescent's problem behaviors in childhood. Prenatal maternal smoking was also associated with elevated rates of adolescent drinking, particularly current drinking. Of the child-rearing variables, only a rule against drinking decreased adolescent drinking. CONCLUSIONS: Selected prenatal factors may constitute risks for alcohol consumption among adolescent daughters. The results are discussed in light of animal models that document increased vulnerability among female offspring to the deleterious effects of gestational alcohol exposure. Implications for understanding the risk factors associated with adolescent alcohol use are discussed.

Relationships between frequency and quantity of marijuana use and last year proxy dependence among adolescents and adults in the United States.

The association between levels of marijuana use and last year dependence is investigated in a nationally representative sample of adolescents and adults, who used marijuana within the last year (n = 9284). Data are aggregated from three surveys (1991-1993) of the National Household Survey on Drug Abuse. A proxy measure of DSM-IV dependence criteria was developed from self-reported symptoms of dependence and drug-related problems. Both frequency and quantity of marijuana use within the last year are linearly associated with the logit of the probability of being dependent on marijuana. The associations vary significantly by age but not gender. Adolescents are dependent at a lower frequency and quantity of use than adults: the differences diverge as level of use increases. Twice as many adolescents as adults who used marijuana near-daily or daily within the last year were identified as being dependent (35% versus 18%). Frequency and quantity of use each retained a unique effect on dependence, but frequency appeared to be more important than quantity in predicting last year dependence. These results provide insight into the processes underlying the age and sex differentials observed in the prevalence of marijuana dependence. The implications of the findings for the epidemiology of marijuana use and dependence are discussed.

College on problems of drug dependence meeting, Puerto Rico (June 1996) marijuana use and dependence.

Discoveries concerning an endogenous cannabinoid system and observations of dramatic increases in marijuana use among youth in the United States have fueled a recent increase in basic and clinical research to better understand and treat marijuana dependence. At the annual meeting of the College on Problems of Drug Dependence (Puerto Rico, 1996) a symposium 'Marijuana Use: Basic Mechanisms, Epidemiology, and Clinical Issues' reviewed a number of important areas of ongoing research that address marijuana dependence. Overviews and original research were presented regarding the development of dependence (preclinical and clinical research), motivational effects (laboratory models), the epidemiology of dependence and its development, clinical management of marijuana use among patients seeking treatment for other drugs of abuse, and treatment for adult marijuana dependence. This paper summarizes the symposium presentations and provides discussion of recent scientific developments concerning marijuana use and dependence.

Psychiatric disorders associated with substance use among children and adolescents: findings from the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study.

The relationships between specific quantities and frequencies of alcohol, cigarette, and illicit substance use and substance use (SUD) and other psychiatric disorders were investigated among 1,285 randomly selected children and adolescents, aged 9 to 18, and their parents, from the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study. Logistic regressions indicated that daily cigarette smoking, weekly alcohol consumption, and any illicit substance use in the past year were each independently associated with an elevated likelihood of diagnosis with SUD and other psychiatric disorders (anxiety, mood, or disruptive behavior disorders), controlling for sociodemographic characteristics (age, gender, ethnicity, family income). The associations between the use of specific substances and specific psychiatric disorders varied as a function of gender.

Effects of chronic cocaine use on physical health: a prospective study in a general population sample.

Few studies have examined long-term effects of chronic cocaine use on physical health in the general population. The current study assesses the effects of chronic cocaine use by the late twenties on physical health by the mid thirties in a longitudinal cohort from the general population. Measures of physical health included self-reported health status, cardiovascular, neurological, and somatic symptoms, and number of hospital or sick days within the last year. The casual analyses were restricted to males because few females used cocaine heavily and the relationships between females' cocaine use and physical health were rarely significant. Among males, chronic cocaine use increased physical health problems, controlling for prior health status, current cocaine use, use of other drugs and sociodemographic characteristics. In turn, poor health contributed to continued cocaine use. Variance partitioning based on cocaine use patterns (frequency and chronicity) indicated that chronic users experienced the most adverse consequences on subsequent physical health. Implications for understanding how chronic cocaine use affects a broad spectrum of physical functioning are discussed.

The NIMH Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study: background and methodology.

OBJECTIVE: A collaborative study was conducted to develop methods for surveys of mental disorder and service utilization in unscreened population-based samples of children and adolescents. METHOD: Probability household samples of youths 9 through 17 years of age were selected at four sites and interviews were conducted with a total of 1,285 pairs of youths and their adult caretakers in their homes. Lay interviewers administered a computer-assisted version of the NIMH Diagnostic Interview Schedule for Children Version 2.3 and structured interviews to assess demographic variables, functional impairment, risk factors, service utilization, and barriers to service utilization. RESULTS: More than 7,500 households were enumerated at four sites, with enumeration response rates above 99%. Across sites, 84% of eligible youth-caretaker pairs were interviewed for about 2 hours each. Ninety-five percent of both youths and caretakers found the interview to be acceptable enough to recommend to a friend. CONCLUSIONS: These findings indicate that large-scale epidemiological surveys of mental disorders and mental health service use involving lengthy interviews in the homes of unscreened population-based samples of youths and their adult caretakers are acceptable to the community and can achieve good response rates. The other reports in this Special Section address the reliability and validity of the various survey instruments and other key findings.

High school students who use crack and other drugs.

BACKGROUND: When it appeared in the 1980s, crack was thought to represent a completely new pathway of entry into drug use. Our objective was to identify the distinguishing characteristics of adolescents who have reached different stages of drug use, in particular the highest state represented by crack. METHODS: Adolescents (N = 7611) representative of students in grades 7 to 12 from 53 New York state schools were classified in the following six mutually exclusive, cumulative categories of drug use: nonusers; alcohol and/or cigarette users only; marijuana users only; users of illicit drugs other than marijuana but neither cocaine nor crack; cocaine but not crack users; and crack users. The groups were compared in level of psychosocial functioning. RESULTS: Students who use illicit drugs show deficits in school performance, quality of family relationships, and health and increased psychological symptoms. Compared with nonusers, they are more delinquent and more actively involved with their peers and live in social environments in which the perceived use of drugs by other adolescents and parents is more extensive. Delinquency and extent of perceived drug use consistently increase with each higher stage of use. Crack users exhibit the lowest level of psychosocial functioning of any drug-using group. CONCLUSIONS: There are stage-specific characteristics and common characteristics (delinquent participation, peer drug use) throughout the developmental sequence of drug use. Despite declines over the last two decades in the prevalence of the use of different drugs, young people who use drugs display characteristics over historical time similar to those of young drug users 20 years ago.

The natural history of drug use from adolescence to the mid-thirties in a general population sample.

OBJECTIVES: This study sought to describe patterns of initiation, persistence, and cessation in drug use in individuals from their late 20s to their mid-30s, within a broad perspective that spans 19 years from adolescence to adulthood. METHODS: A fourth wave of personal interviews was conducted at ages 34-35 with a cohort of men and women (n = 1160) representative of adolescents formerly enrolled in New York State public secondary high schools. A school survey was administered at ages 15-16, and personal interviews with participants and school absentees were conducted at ages 24-25 and 28-29. Retrospective continuous histories of 12 drug classes were obtained at each follow-up. RESULTS: There was no initiation into alcohol and cigarettes and hardly any initiation into illicit drugs after age 29, the age at which most use ceased. The largest proportion of new users was observed for prescribed psychoactives. Periods of highest use since adolescence based on relative and absolute criteria were delineated. Among daily users, the proportions of heavy users declined for alcohol and marijuana but not for cigarettes. CONCLUSIONS: Cigarettes are the most persistent of any drug used. Drug-focused interventions must target adolescents and young adults.

Maternal smoking during pregnancy and smoking by adolescent daughters.

OBJECTIVES: Since cigarette smoking in adolescence represents a crucial entry point in the progression to illicit drugs, risk factors for adolescent smoking have public health implications. The influence of mothers on children's smoking appears to be greater than that of fathers. To explain the selective influence of mothers, we examined the consequences of maternal smoking during pregnancy in two longitudinal samples. METHODS: Analyses were conducted on follow-up interview data from two dyadic samples of mothers and firstborn adolescents for whom data on maternal smoking during and after pregnancy were available (192 mother-child pairs originating from New York State and 797 dyads from a national sample). RESULTS: In both samples, maternal smoking during pregnancy, when postnatal smoking was controlled, selectively increased the probability that female children would smoke and would persist in smoking (adjusted odds ratios of about 4). CONCLUSIONS: The findings suggest that nicotine or other substances released by maternal smoking can affect the fetus, perhaps through the nicotinic input to the dopaminergic motivational system, so as to predispose the brain in a critical period of its development to the subsequent addictive influence of nicotine consumed more than a decade later in life.

Stages of progression in drug involvement from adolescence to adulthood: further evidence for the gateway theory.

Sequential stages of involvement in alcohol and/or cigarettes, marijuana, other illicit drugs and medically prescribed psychoactive drugs from adolescence to adulthood are investigated in a longitudinal cohort that has been followed from ages 15 to 35. Alternative models of progression are tested for their goodness of fit. Four stages are identified: that of legal drugs, alcohol or cigarettes; marijuana; illicit drugs other than marijuana; and medically prescribed drugs. Whereas progression to illicit drugs among men is dependent upon prior use of alcohol, among women either cigarettes or alcohol is a sufficient condition for progression to marijuana. Age of onset and frequency of use at a lower stage of drug use are strong predictors of further progression.

Drug use as a risk factor for premarital teen pregnancy and abortion in a national sample of young white women.

The relationship between adolescent drug use and premarital teen pregnancy and abortion as a pregnancy outcome among sexually active women is investigated in a sample of white women from the National Longitudinal Survey of Youth. Event history analysis is used to explore whether prior drug use has a unique effect on premarital teen pregnancy, with controls for personality, lifestyle, and biological factors. Logistic regression is used to estimate whether drug use affects the decision to terminate a premarital teen pregnancy. The results show that the risk of premarital teen pregnancy is nearly four times as high for those who have used illicit drugs other than marijuana as for those with no history of any prior substance involvement. Furthermore, illicit drug use increases the likelihood of an abortion by a factor of 5. Policy implications of the findings are discussed.