Nominal association with CHRNA4 variants and nicotine dependence

Nicotine binds to nicotinic acetylcholine receptors and studies in animal models have shown that α4β2 receptors mediate many behavioral effects of nicotine. Human genetics studies have provided support that variation in the gene that codes for the α4 subunit influences nicotine dependence (ND), but the evidence for the involvement of the β2 subunit gene is less convincing. In this study, we examined the genetic association between variation in the genes that code for the α4 (CHRNA4) and β2 (CHRNB2) subunits of the nicotinic acetylcholine receptor and a quantitative measure of lifetime DSM-IV ND symptom counts. We performed this analysis in two longitudinal family-based studies focused on adolescent antisocial drug abuse: the Center on Antisocial Drug Dependence (CADD, N = 313 families) and Genetics of Antisocial Drug Dependence (GADD, N = 111 families). Family-based association tests were used to examine associations between 14 single nucleotide polymorphisms (SNPs) in CHRNA4 and CHRNB2 and ND symptoms. Symptom counts were corrected for age, sex and clinical status prior to the association analysis. Results, when the samples were combined, provided modest evidence that SNPs in CHRNA4 are associated with ND. The minor allele at both rs1044394 (A; Z = 1.988, P = 0.047, unadjusted P-value) and rs1044396 (G; Z = 2.398, P = 0.017, unadjusted P-value) was associated with increased risk of ND symptoms. These data provide suggestive evidence that variation in the α4 subunit of the nicotinic acetylcholine receptor may influence ND liability.

Developmental epidemiology of drug use and abuse in adolescence and young adulthood: Evidence of generalized risk

Past studies highlight a narrowing gender gap and the existence of a shared etiology across substances of abuse; however, few have tested developmental models using longitudinal data. We present data on developmental trends of alcohol, tobacco, and marijuana use, abuse and dependence assessed during adolescence and young adulthood in a community-based Colorado twin sample of 1733 respondents through self-report questionnaires and structured psychiatric interviews. Additionally, we report on the rates of multiple substance use and disorders at each developmental stage, and the likelihood of a substance use disorder (SUD; i.e., abuse or dependence) diagnosis in young adulthood based on adolescent drug involvement. Most notably, we evaluate whether the pattern of multiple substance use and disorders and likelihood ratios across substances support a model of generalized risk. Lastly, we evaluate whether the ranked magnitudes of substance-specific risk match the addiction liability ranking. Substance use and SUDs are developmental phenomena, which increase from adolescence to young adulthood with few and inconsistent gender differences. Adolescents and young adults are not specialized users, but rather tend to use or abuse multiple substances increasingly with age. Risk analyses indicated that progression toward a SUD for any substance was increased with prior involvement with any of the three substances during adolescence. Despite the high prevalence of alcohol use, tobacco posed the greatest substance-specific risk for developing subsequent problems. Our data also confirm either a generalized risk or correlated risk factors for early onset substance use and subsequent development of SUDs.

Mate similarity for substance dependence and antisocial personality disorder symptoms among parents of patients and controls

Substance dependence (SD) and antisocial personality disorder (ASPD) are highly comorbid and aggregate in families. Mating assortment may be an important process contributing to this familial aggregation.

HYPOTHESIS

Symptom counts of substance dependence, antisocial personality disorder, and retrospectively assessed conduct disorder (CD) will be correlated significantly among parents of youth in treatment for substance use and conduct problems and, separately, among parents of community controls.

METHODS

We examined SD, ASPD, and CD among 151 pairs of parents of adolescents in treatment for substance use and conduct problems, and in 206 pairs of parents of control subjects.

RESULTS

For average dependence symptoms (ADS) (the sum of across-drug substance dependence symptoms divided by the number of substance categories meeting minimum threshold use) mother-father correlations were 0.40 for patients and 0.28 for controls. Mother--father correlations for ASPD symptom count were 0.33 for patients and 0.26 for controls and for CD symptom count were 0.31 for patients (all P < 0.01) and 0.10 for controls (P = 0.14).

CONCLUSIONS

Spousal correlations for ADS and ASPD, suggest substantial non-random mating. Results support gender differences in homogamy for SD. Behavior genetic studies of these disorders need to account for assortment to avoid biases in estimates of genetic and environmental effects.

Substance use, abuse and dependence in adolescence: prevalence, symptom profiles and correlates

We present data on the lifetime prevalence of substance use, abuse and dependence in adolescents obtained through structured psychiatric interviews and self-report questionnaires. Most notably, we evaluate symptom profiles based on DSM-IV abuse and dependence criteria for tobacco, alcohol and marijuana, including a gender comparison. Participants are 3,072 adolescents (12-18 years) drawn from three community-based family samples in Colorado. Age trends suggest that substance use is a developmental phenomenon, which increases almost linearly from early to late adolescence. Substance use disorders are less common than experimentation in adolescence, but approximately 1 in 4 adolescents in the oldest cohorts meets criteria for abuse for at least one substance, and 1 in 5 meets criteria for substance dependence. By age 18 nearly 1 in 3 adolescents report daily smoking and 8.6% meet criteria for tobacco dependence. Although alcohol is the most commonly abused substance (10%), a slightly larger proportion of adolescents meet criteria for dependence on marijuana (4.3%) than alcohol (3.5%). Gender differences in prevalence of use more often show greater use in males than females. Males more frequently meet criteria for dependence on alcohol and marijuana in late adolescence, while females are more often nicotine dependent. A comparison of abuse and dependence symptom profiles shows some interesting variability across substances, and suggests that manifestations of a subset of symptoms are gender specific.

Validity of structured clinical evaluations in adolescents with conduct and substance problems

OBJECTIVE

To determine discriminative and convergent validity for certain structured diagnostic assessments among adolescents with conduct and substance problems.

METHOD

Patients were 87 adolescents (both genders) in treatment for conduct and substance problems. Most controls (n = 85; both genders) came from patients' neighborhoods. Assessments included Diagnostic Interview Schedule for Children, Composite International Diagnostic Instrument-Substance Abuse Module, Child Behavior Checklist, and others. Patients' data guided clinical care.

RESULTS

Youths' self-reports significantly discriminated patients from controls in DSM-IVconduct and substance use disorders (CD, SUD) and in numerous associated measures. CD and SUD symptoms correlated strongly. However, some patients apparently minimized symptoms. Youths' self-reports did not discriminate patients from controls in attention-deficit/hyperactivity disorder (ADHD) or major depression (MDD). Parent information raised prevalence rates of ADHD and MDD, which then discriminated patients from controls. However, patients and parents usually disagreed on MDD and ADHD diagnoses.

CONCLUSIONS

Despite some dissimulation, patients' self-reports of CD and SUD correlated highly and had superb discriminative validity, making them useful for treatment and research. Self-reports of ADHD and MDD, apparently lacking discriminative validity, are less useful. Parent reports improve these discriminations but present additional problems.

Concordance between DSM-III-R and DSM-IV diagnoses of substance use disorders in adolescents

Except for cannabis and alcohol, concordance between DSM-III-R and DSM-IV substance use disorder diagnoses has not been reported in adolescents. We assessed a clinical sample of 102 adolescents using CIDI-SAM. Prevalence of either an abuse or dependence diagnosis was lower with DSM-IV than DSM-III-R except for cannabis and alcohol, and concordance rates were better for dependence than for abuse. For most substances, rates of DSM-IV withdrawal were lower than in DSM-III-R, but rates of DSM-IV physiological dependence remained high. Changes in DSM-IV criteria appear to have impacted diagnoses in these adolescents, particularly for the substances they use most--i.e. alcohol, tobacco, and cannabis.

Heroin use among adolescents in treatment for substance use disorders

OBJECTIVE

To clarify prevalence rates and describe patterns of adolescent heroin users who are in treatment for substance use disorders.

METHOD

The Treatment Episode Data Set (TEDS) was examined for trends in the number of adolescents admitted to substance abuse treatment centers and for changes in the routes of heroin administration. Thirteen adolescents who used heroin from one treatment program were compared with 536 adolescents who did not.

RESULTS

Between 1992 and 1996, heroin-using youths represented 2.0% of youths in treatment and in 1997 they represented 2.6%. Heroin-using youths represented 56% of those using injection drugs. Heroin-using youths from one treatment program had significantly more polysubstance dependence in comparison with adolescents who did not use heroin.

CONCLUSIONS

Nationally, there has been an increasing number, but not percentage, of heroin-using youths in treatment between 1992 and 1996. In 1997 there was an increase in both the number and percentage of heroin-using youths in treatment. Heroin-using adolescents have the highest rate of injection drug use when compared with youths using other substances. Because of their greater risk of contracting human immunodeficiency virus through injection drug use, treatment trials for these adolescents are needed.

Causes of climate change over the past 1000 years

Recent reconstructions of Northern Hemisphere temperatures and climate forcing over the past 1000 years allow the warming of the 20th century to be placed within a historical context and various mechanisms of climate change to be tested. Comparisons of observations with simulations from an energy balance climate model indicate that as much as 41 to 64% of preanthropogenic (pre-1850) decadal-scale temperature variations was due to changes in solar irradiance and volcanism. Removal of the forced response from reconstructed temperature time series yields residuals that show similar variability to those of control runs of coupled models, thereby lending support to the models' value as estimates of low-frequency variability in the climate system. Removal of all forcing except greenhouse gases from the approximately 1000-year time series results in a residual with a very large late-20th-century warming that closely agrees with the response predicted from greenhouse gas forcing. The combination of a unique level of temperature increase in the late 20th century and improved constraints on the role of natural variability provides further evidence that the greenhouse effect has already established itself above the level of natural variability in the climate system. A 21st-century global warming projection far exceeds the natural variability of the past 1000 years and is greater than the best estimate of global temperature change for the last interglacial.

Neoproterozoic 'snowball Earth' simulations with a coupled climate/ice-sheet model

Ice sheets may have reached the Equator in the late Proterozoic era (600-800 Myr ago), according to geological and palaeomagnetic studies, possibly resulting in a 'snowball Earth'. But this period was a critical time in the evolution of multicellular animals, posing the question of how early life survived under such environmental stress. Here we present computer simulations of this unusual climate stage with a coupled climate/ice-sheet model. To simulate a snowball Earth, we use only a reduction in the solar constant compared to present-day conditions and we keep atmospheric CO2 concentrations near present levels. We find rapid transitions into and out of full glaciation that are consistent with the geological evidence. When we combine these results with a general circulation model, some of the simulations result in an equatorial belt of open water that may have provided a refugium for multicellular animals.

Respiration during snow burial using an artificial air pocket

CONTEXT

Asphyxia is the most common cause of death after avalanche burial. A device that allows a person to breathe air contained in snow by diverting expired carbon dioxide (CO2) away from a 500-cm3 artificial inspiratory air pocket may improve chances of survival in avalanche burial.

OBJECTIVE

To determine the duration of adequate oxygenation and ventilation during burial in dense snow while breathing with vs without the artificial air pocket device.

DESIGN

Field study of physiologic respiratory measures during snow burial with and without the device from December 1998 to March 1999. Study burials were terminated at the subject's request, when oxygen saturation as measured by pulse oximetry (SpO2) dropped to less than 84%, or after 60 minutes elapsed.

SETTING

Mountainous outdoor site at 2385 m elevation, with an average barometric pressure of 573 mm Hg.

PARTICIPANTS

Six male and 2 female volunteers (mean age, 34.6 years; range, 28-39 years).

MAIN OUTCOME MEASURES

Burial time, SpO2, partial pressure of end-tidal CO2 (ETCO2), partial pressure of inspiratory CO2 (PICO2), respiratory rate, and heart rate at baseline (in open atmosphere) and during snow burial while breathing with the device and without the device but with a 500-cm3 air pocket in the snow.

RESULTS

Mean burial time was 58 minutes (range, 45-60 minutes) with the device and 10 minutes (range, 5-14 minutes) without it (P=.001). A mean baseline SpO2 of 96% (range, 90%-99%) decreased to 90% (range, 77%-96%) in those buried with the device (P=.01) and to 84% (range, 79%-92%) in the control burials (P=.02). Only 1 subject buried with the device, but 6 control subjects buried without the device, decreased SpO2 to less than 88% (P=.005). A mean baseline ETCO2 of 32 mm Hg (range, 27-38 mm Hg) increased to 45 mm Hg (range, 32-53 mm Hg) in the burials with the device (P=.02) and to 54 mm Hg (range, 44-63 mm Hg) in the control burials (P=.02). A mean baseline PICO2 of 2 mm Hg (range, 0-3 mm Hg) increased to 32 mm Hg (range, 20-44 mm Hg) in the burials with the device (P=.01) and to 44 mm Hg (range, 37-50 mm Hg) in the control burials (P=.02). Respiratory and heart rates did not change in burials with the device but significantly increased in control burials.

CONCLUSIONS

In our study, although hypercapnia developed, breathing with the device during snow burial considerably extended duration of adequate oxygenation compared with breathing with an air pocket in the snow. Further study will be needed to determine whether the device improves survival during avalanche burial.

One-year outcome of adolescent females referred for conduct disorder and substance abuse/dependence

We investigated whether substance abuse/dependence, conduct disorder, and other psychiatric disorders improved in adolescent females who were referred to outpatient treatment and which variables were related to 1-year outcome. Forty-six out of 60 conduct-disordered (CD) adolescent females with substance abuse or dependence were re-evaluated approximately 1 year after discharge. Treatment length averaged 16 weeks. Significant improvements were seen in three areas: (1) criminality and CD; (2) attention deficit hyperactivity disorder (ADHD); and (3) educational and vocational status. However, neither substance involvement nor depression improved, regardless of length of stay in treatment, and these females demonstrated significant risky sexual behaviors. In contrast to our previous work with adolescent males (Crowley, T.J., Mikulich, S.K., Macdonald, M., Young, S.E., Zerbe, G.O., 1998. Substance-dependent, conduct-disordered adolescent males: severity of diagnosis predicts 2-year outcome. Drug Alcohol Depend. 49, 225-237), we were not able to identify pre-intake variables, other than performance IQ, that were related to substance use and conduct outcomes. Only two post-treatment factors (peer problems and number of ADHD symptoms at follow-up) were found to be related to CD and substance use disorders outcomes. The overall lack of pre- and post-treatment predictors presents interesting challenges for future research on adolescent females with these disorders.

Relating the classical covariance adjustment techniques of multivariate growth curve models to modern univariate mixed effects models

The relationship between the modern univariate mixed model for analyzing longitudinal data, popularized by Laird and Ware (1982, Biometrics 38, 963-974), and its predecessor, the classical multivariate growth curve model, summarized by Grizzle and Allen (1969, Biometrics 25, 357-381), has never been clearly established. Here, the link between the two methodologies is derived, and balanced polynomial and cosinor examples cited in the literature are analyzed with both approaches. Relating the two models demonstrates that classical covariance adjustment for higher-order terms is analogous to including them as random effects in the mixed model. The polynomial example clearly illustrates the relationship between the methodologies and shows their equivalence when all matrices are properly defined. The cosinor example demonstrates how results from each method may differ when the total variance-covariance matrix is positive definite, but that the between-subjects component of that matrix is not so constrained by the growth curve approach. Additionally, advocates of each approach tend to consider different covariance structures. Modern mixed model analysts consider only those terms in a model's expectation (or linear combinations), and preferably the most parsimonious subset, as candidates for random effects. Classical growth curve analysts automatically consider all terms in a model's expectation as random effects and then investigate whether "covariance adjusting" for higher-order terms improves the model. We apply mixed model techniques to cosinor analyses of a large, unbalanced data set to demonstrate the relevance of classical covariance structures that were previously conceived for use only with completely balanced data.

Relationship of ADHD, depression, and non-tobacco substance use disorders to nicotine dependence in substance-dependent delinquents

This study used standardized interviews to examine the relationship of attention deficit hyperactivity disorder (ADHD), major depression (MDD), and other illicit substance use disorders (SUD) to onset and severity of nicotine dependence in 82 female and 285 male adolescents with conduct disorder (CD) and SUD. Results indicate that both ADHD and MDD significantly contribute to severity of nicotine dependence in delinquents with SUD. ADHD is further associated with earlier onset of regular smoking in males. Severity of non-tobacco SUD also was related directly to nicotine dependence severity in both males and females, and to earlier onset of smoking in males. Our findings illuminate the contribution of comorbidity to nicotine dependence and its relationship to other SUD severity among adolescents with CD and SUD and highlight the need for coordinated assessment and treatment of smoking cessation along with concurrent treatment of other drug use and psychiatric comorbidity such as ADHD and MDD in such youths.

Local orbital forcing of antarctic climate change during the last interglacial

During the last interglacial, Antarctic climate changed before that of the Northern Hemisphere. Large local changes in precession forcing could have produced this pattern if there were a rectified response in sea ice cover. Results from a coupled sea ice-ocean general circulation model supported this hypothesis when it was tested for three intervals around the last interglacial. Such a mechanism may play an important role in contributing to phase offsets between Northern and Southern Hemisphere climate change for other time intervals.

Cannabis dependence, withdrawal, and reinforcing effects among adolescents with conduct symptoms and substance use disorders

The prevalence of cannabis use is rising among adolescents, many of whom perceive little risk from cannabis. However, clinicians who treat adolescent substance users hear frequent reports of serious cannabis-use disorders and problems. This study asked whether cannabis produced dependence and withdrawal among such patients, and whether patients' reports supported previous laboratory findings of reinforcing effects from cannabis. This was a screening and diagnostic study of serial treatment admissions. The diagnostic standard was the DSM-III-R dependence criteria, and the setting was a university-based adolescent substance treatment program with male residential and female outpatient services. The patients were 165 males and 64 females from consecutive samples of 255 male and 85 female 13-19-year-olds referred for substance and conduct problems (usually from social service or criminal justice agencies). Eighty-seven patients were not evaluated, usually due to early elopement. Twenty-four others did not meet study admission criteria: > or = one dependence diagnoses and > or = three lifetime conduct-disorder symptoms. The main measures were items from diagnostic interview instruments for substance dependence, psychiatric disorders, and patterns of substance use. Diagnoses were substance dependence, 100%; current conduct disorder, 82.1%; major depression, 17.5%; attention-deficit/hyperactivity disorder, 14.8%. The results show that most patients claimed serious problems from cannabis, and 78.6% met standard adult criteria for cannabis dependence. Two-thirds of cannabis-dependent patients reported withdrawal. Progression from first to regular cannabis use was as rapid as tobacco progression, and more rapid than that of alcohol, suggesting that cannabis is a reinforcer. The data indicate that for adolescents with conduct problems cannabis use is not benign, and that the drug potently reinforces cannabis-taking, producing both dependence and withdrawal. However, findings from this severely affected clinical population should not be generalized broadly to all other adolescents.

Family variables in substance-misusing male adolescents: the importance of maternal disorder

Selected family variables, especially maternal behaviors, were studied as predictors of alcohol and drug misuse in severely disturbed adolescent boys from largely father-absent homes. The families of 50 male youths (mean age 15.8 years) in a residential center for alcohol and substance misuse were compared with the families of a community control group (mean age 16.3 years). Within-subject group comparisons also were made. Family structure, interactive processes, maternal and paternal alcohol and substance use, and criminality were assessed through direct interview and/or self-report. The families of alcohol- and substance-misusing boys were markedly disadvantaged or impaired on numerous family structure, process, and substance-misusing behavioral variables in comparison with community controls. Within the alcohol- and substance-misusing group itself, family process variables, maternal alcohol symptoms, and maternal criminality differentiated boys with more vs. less severe drug-dependence symptoms. Maternal alcohol problems and criminality were more important than family process variables. Paternal alcohol or substance misuse or criminality did not differentiate proband symptom severity. We concluded that maternal alcohol symptoms and criminality differentiate severity of drug dependence in severely disturbed, substance-misusing adolescent males from largely father-absent homes. Maternal substance misuse should be evaluated carefully in adolescent substance abuse treatment settings.

Substance-dependent, conduct-disordered adolescent males: severity of diagnosis predicts 2-year outcome

Most delinquent youths have conduct disorder (CD), often with comorbid substance use disorder (SUD), attention-deficit/hyperactivity disorder (ADHD) and depression. Some youths' conduct problems later abate, while those of others persist into adult antisocial personality disorder. Earlier CD onset and ADHD reportedly predict persisting antisocial problems, but predictors of persisting SUD are poorly understood. Males aged 13-19 years (n = 89), most referred by criminal justice and social service agencies, received residential treatment for comorbid CD and SUD. They had diagnostic assessments for SUD at intake and for CD, ADHD, and depression (as well as drug-use assessments) at intake and 6, 12 and 24 months later. At intake nearly all had DSM-III-R substance dependence (usually on alcohol and marijuana) and CD with considerable violence and criminality. The 2-year follow-ups revealed improvements in criminality, CD, depression and ADHD, but substance use remained largely unchanged. Various aspects of conduct, crime and substance outcomes at 2 years were predicted by intake measures of intensity of substance involvement, and by CD severity and onset age, but not by severity of either ADHD or depression, nor by treatment duration. Earlier CD onset, more severe CD and more drug dependence predicted worse outcomes, supporting the validity of these diagnoses in adolescents.

A family history and direct interview study of the familial aggregation of substance abuse: the adolescent substance abuse study

The adolescent substance abuse (ASA) study collected information concerning drug use and psychopathology on male adolescent probands in treatment for substance abuse and also on matched control adolescents, as well as all available family members of both groups. Information was obtained through direct interview and the family history method of assessment. Both methods revealed greater alcohol and drug use, conduct disorder (CD) and antisocial personality disorder (ASP) in the relatives of treatment probands as compared with control relatives. These results suggest familial transmission, not only for alcohol abuse, but also for non-alcohol substance abuse. Familial transmission for CD and ASP is also evident for both male and female relatives, although the prevalence of these disorders is significantly greater in males than females.

Fluoxetine in drug-dependent delinquents with major depression: an open trial

Although fluoxetine might be more effective than placebo for treating adolescent depression without major comorbidity, little is known about the response of depressive symptoms to antidepressants in adolescents with comorbid conduct disorder (CD) and substance use disorders (SUD). Male adolescents, who remained or became depressed after > or = 1 month of abstinence from abused substances during residential treatment for SUD, were treated in an open trial for > or = 7 weeks with a fixed dose of 20 mg of fluoxetine. The eight adolescents (ages 14-18 years) with CD, SUD, and major depression were not in drug withdrawal or receiving other pharmacotherapy. A > or = 50% improvement was observed in mean scores on Ten Point Depression Scale rated by clinician (p < 0.01) and patients (p < 0.01), Carroll Self-Ratings for depression (p < 0.02), and Severity of Illness scores on the Clinical Global Impression (p < 0.01). Of the eight adolescents, seven showed marked improvement and wished to continue fluoxetine after the trial. Side effects were mild and transient. No subject required dosage reduction or discontinuation of medication because of side effects. Fluoxetine appeared useful in treating substance-dependent delinquents whose major depressions persisted or emerged after 4 weeks of abstinence. These preliminary findings justify a controlled trial in such youths.

Influences on adolescent substance dependence: conduct disorder, depression, attention deficit hyperactivity disorder, and gender

OBJECTIVE

In adolescents, conduct disorder (CD), attention deficit hyperactivity disorder (ADHD), and depression are frequently comorbid with substance dependence (SD). We hypothesized that the prevalence and severity of CD, major depressive disorder (MDD), and ADHD would differ by gender, and that these conditions would associate differentially with severity of SD in males and females.

METHODS

We examined these issues, using standardized diagnostic interviews, in 285 male and 82 female adolescents referred for comorbid CD and SD.

RESULTS

Males and females did not differ significantly in severity of substance involvement, MDD, or ADHD, but males had more severe CD. MDD severity was the only variable significantly associated with SD severity for females, while for males, severity of CD combined with MDD and ADHD was significantly associated with SD severity.

CONCLUSIONS

Among referred adolescents, CD, MDD, and ADHD may all be important concomitants of SD in males, while in females, depression may be the primary variable related to SD.

Substance abuse treatment entry, retention and effectiveness: out-of-treatment opiate injection drug users

This study was designed to assess the effect of client characteristics and community interventions on treatment entry and retention, and to evaluate the relative effectiveness of treatment, compared to other interventions, in reducing drug use and crime among out-of-treatment opiate injectors. Subjects (N = 2973) from 15 cities were randomly assigned to: standard intervention (SI)-HIV testing and counseling; or enhanced intervention (EI)-SI plus additional educational sessions stressing responsible drug use. EI in some cities included staff assistance with treatment admission (i.e. "active' referral). All locations provided intervention by community outreach workers. Factors positively associated with treatment entry included: prior treatment, intervention by community workers, assignment to the EI, not injecting cocaine, injecting opiates, and fewer program interventions received. Sites where the EI included active referral achieved significantly higher treatment entry rates than sites where the EI did not. Findings supported the efficacy of treatment over other interventions in reducing drug use and arrests, the addition of staff assistance to facilitate clients' entry into treatment, and the involvement of community outreach workers in achieving treatment entry.

An open trial of pemoline in drug-dependent delinquents with attention-deficit hyperactivity disorder

OBJECTIVE

Adolescents with conduct disorder and substance use disorders have high rates of comorbid attention-deficit hyperactivity disorder (ADHD); ADHD may contribute to the severity and persistence of substance use disorders and antisocial behaviors. Treatment of ADHD may help patients utilize substance and other behaviorally focused treatment. Yet little is known about the response of ADHD symptoms to psychopharmacological intervention in substance-dependent delinquents.

METHOD

Pilot data are presented for 13 male adolescents with conduct disorder, substance use disorders, and ADHD, in a residential substance use treatment program. Patients were treated with pemoline. Scores from the Conners Hyperactivity Index and continuous performance tasks were obtained at baseline and after about 1 month of treatment with pemoline. Physical activity measurements were also assessed at baseline and 1 month. Postmedication assessments were obtained after at least 1 week at maximal dosage (1.2 to 3.3 mg/kg).

RESULTS

Mean Conners Hyperactivity Index scores declined 13.9% (p < or = .002) and mean motility declined 7% (p < or = .04) with pemoline treatment. Continuous performance task scores did not change.

CONCLUSIONS

Preliminary data indicate that pemoline may be a useful treatment for ADHD in substance-dependent delinquents; the authors propose a controlled trial of pemoline in such youths.

Contribution of ADHD symptoms to substance problems and delinquency in conduct-disordered adolescents

We examined adolescents with conduct disorder (CD) and substance problems to determine if those with attention deficit hyperactivity disorder (ADHD) symptomatology had more severe delinquency and substance involvement. ADHD symptomatology was assessed in two ways: (1) by self-reports using the Diagnostic Interview Schedule for Children (DISC) and (2) by use of DISC plus reports of others (parents, program staff, and program teacher). We divided boys into three ADHD groups based on DISC: those who met criteria, those who reported at least eight current symptoms, and those who reported fewer than eight symptoms. We also divided the same boys into two groups: those with reports of ADHD by two or more sources and those without this multisource ADHD. Examining these definitions of ADHD revealed that boys with either self- or multisource ADHD had more CD symptoms, earlier age of CD onset, more substance dependence diagnoses, and more comorbid depression and anxiety.

Depression in substance-dependent delinquents

OBJECTIVE

Depression often is comorbid with conduct disorder. The purpose of this study is to assess whether, among youths with conduct disorder, those with depression differ in other ways from those without depression.

METHOD

Ninety-nine delinquent boys (aged 13 through 19 years) were evaluated with the Diagnostic Interview Schedule for Children and other instruments. All boys had conduct disorder and substance use disorders.

RESULTS

Staff-rated and self-rated depression scores correlated significantly. Twenty-one boys had major depression and/or dysthymia. Depressed boys had more substance dependence diagnoses and were more likely to have attention-deficit hyperactivity disorder, posttraumatic stress disorder, and anxiety disorders, compared with the nondepressed boys. Depressed boys tended to develop conduct symptoms earlier than did the nondepressed boys. Depression scores did not change after at least 4 weeks of abstinence, for either depressed or nondepressed boys.

CONCLUSIONS

Depressed delinquents have more substance dependence diagnoses, tend to initiate behavioral problems at an earlier age, have increased anxiety and attentional problems, and more trauma effects, than nondepressed delinquents. Depression does not appear to be related to substance intoxication, since it is not alleviated after 4 weeks of abstinence. Such boys may require combined psychiatric and substance treatment.

Behavioral anti-smoking trial in chronic obstructive pulmonary disease patients

Smoking causes chronic obstructive pulmonary disease (COPD), but few controlled studies have tested anti-smoking treatments in COPD. With procedures likely to attract unmotivated persons we recruited 49 quite-ill, smoking COPD patients. During one or two daily home visits for 85 days, breath carbon monoxide (CO) and self-reports of daily smoking were obtained. Patients, given quit dates and nicotine gum (2-mg pieces, up to 30 per day), were assigned randomly to three groups: Experimentals were reinforced with lottery tickets for CO < 10 ppm. Cigarette Self Report (CSR) patients were reinforced for reporting no smoking that day. Controls received non-contingent payments. Each group's mean CO level fell at the quit date. Thereafter, reinforced patients maintained significantly lower CO levels than Controls. Although many more 24-h abstentions occurred in the intervention period than in baseline, few patients sustained abstinence; the groups did not differ in that regard. Outcome was predicted by decisions to throw away cigarettes when intervention began, but not by motivation scales nor Fagerstrom dependence scores. Pay schedules apparently exaggerated self-reports of reduced smoking. Although results are statistically significant, there is still no proven, practical treatment for smoking in advanced COPD.

Treated delinquent boys' substance use: onset, pattern, relationship to conduct and mood disorders

We describe relationships between substance use, conduct disorder (CD), depression, and history of self-injury or suicide attempts, in referred, delinquent, substance involved, adolescent males. Sixty youths (mean age 16.3 years) completed standardized assessments for substance use and other psychiatric disorders, aggressiveness, and social class. All boys met modified criteria for CD. Most had high aggression ratings. Twenty percent had depressive diagnoses. By age 13, 78% had begun regular substance use. Marijuana was the first substance for 42%. The boys had substance dependence on a mean of 3.2 different drugs (usually including alcohol and marijuana), with abuse of an average of one additional drug. CD symptoms began 3.6 years (mean) before regular use. CD symptom count correlated with number of dependence diagnoses, and both of those (but not depression) related significantly to suicide attempt and self-injury histories. Improved understanding of substance involvement in youths with CD may generate more rational prevention and treatment.

Milankovitch Forcing of the Last Interglacial Sea Level

During the last interglacial, sea level was as high as present, 4000 to 6000 years before peak Northern Hemisphere insolation receipt 126,000 years ago. The sea-level results are shown to be consistent with climate models, which simulate a 3 degrees to 4 degrees C July temperature increase from 140,000 to 130,000 years ago in high latitudes, with all Northern Hemisphere land areas being warmer than present by 130,000 years ago. The early warming occurs because obliquity peaked earlier than precession and because precession values were greater than present before peak precessional forcing occurred. These results indicate that a fuller understanding of the Milankovitch-climate connection requires consideration of fields other than just insolation forcing at 65 degrees N.

Buprenorphine and cocaine effects on social behavior of monkeys

We administered for 2 weeks intramuscular buprenorphine 0.3 mg/kg per day (and in a separate series, its vehicle) to each of 7 male, group-living Macaca fuscata (Japanese Snow Monkeys). Animals received one injection of cocaine 0.75 mg/kg and one of saline (about Days 9 and 14) in each series; after each of these doses ethologic observers recorded for 3 h the frequency of occurrence of 64 separate social, self-care, position and other behaviors. Cocaine alone changed the frequency of many behaviors. Buprenorphine alone only reduced the frequency of eating, yawning and ejaculation. The drugs had no interactive effects on behavior. In a dose reported to suppress monkeys' heroin and cocaine self-administration, buprenorphine showed remarkably few disruptions of normal group behavior. But it neither reversed nor enhanced cocaine's behavioral effects.

Increased rat myocardial type VI collagen in diabetes mellitus and hypertension

Diabetic cardiomyopathy, a condition characterized by the accumulation of carbohydrate-containing material surrounding the myocardial small blood vessels, has been studied in alloxan-diabetic normotensive and hypertensive rats. Immunochemical techniques were used to monitor several extracellular matrix constituents present in extracts of cardiac tissue, namely types I, IV and VI collagen, laminin and fibronectin, as well as myosin. These studies have indicated that after induction of diabetes, type VI collagen but none of the other matrix components studied, was significantly increased (from 2.29 +/- 0.04 mg/g in normal to 2.85 +/- 0.18 mg/g in diabetic ventricles, p < 0.01). Hypertension, whether induced by the clipping of one renal artery or genetically determined (spontaneously hypertensive rats), resulted in a similar elevation in type VI collagen (2.71 +/- 0.12 mg/g, p < 0.005 compared to normal rats). In the presence of diabetes plus hypertension the effect was not additive, the type VI collagen level being 2.93 +/- 0.15 (p < 0.001 compared to normal rats). Basement membrane collagen (type IV) in the myocardium appeared to be unaffected by diabetes or hypertension and the myosin contents of the hearts of the four experimental groups were similar. Quantitative determinations indicate that compared to type IV collagen, laminin or fibronectin, type VI collagen represents the major periodic acid-Schiff-reactive extracellular constituent of the rat ventricle. Its preferential increase in the heart in diabetes may provide insight into the molecular mechanisms of the diabetic microvascular disease.

Antisocial personality disorder, HIV risk behavior and retention in methadone maintenance therapy

In a sample of 55 consecutive methadone maintenance admissions to our clinic, 42% were diagnosed with antisocial personality disorder (ASPD) using the National Institute of Mental Health Diagnostic Interview Schedule NIMH DIS. Individuals with ASPD exhibited greater risk for HIV infection as defined by more sexual contacts, needle use and equipment sharing. Data at 1 year follow-up were obtained on this group of patients. The objective was to compare the ASPD and non-ASPD groups with regards to demographics, drug abuse history, outcome and retention in treatment. There were no significant differences between the groups on any demographic or treatment outcome variables. Survival analysis indicated that there were no group differences in treatment retention. In conclusion, although there were no differences in treatment outcome between ASPD and non-ASPD groups it is possible that ASPD patients who drop out of treatment will be at higher risk for contracting and spreading HIV within the IV drug using population. These data also suggest that in this population the diagnosis of ASPD using primarily behavioral traits as measured in the NIMH-DIS-III, has little utility in predicting treatment outcome.

Myocardial glycoproteins in diabetes: type VI collagen is a major PAS-reactive extracellular matrix protein

An investigation of myocardial glycoproteins was undertaken to elucidate the molecules responsible for the periodic acid-Schiff (PAS) reactivity of the increased extracellular matrix of diabetic cardiomyopathy. Perfusion with radiolabeled mannose indicated an enhanced formation of matrix components in the diabetic compared to the normal rat heart. Electrophoretic separation of radiolabeled extracts demonstrated the presence of glycoproteins with Mr values of 205, 142 and 90 kDa which could be separated by Bio-Gel A-5 m filtration. Fractionation of non-perfused hearts resulted in the isolation of only the 205 and 142 kDa components, which were shown by amino acid analyses and collagenase digestion to belong to the collagen family of proteins and by immunoblotting to represent type VI collagen. The carbohydrate content of these rat myocardial type VI collagen subunits, determined from monosaccharide analyses, was 11 and 12%, respectively, and N-glycanase digestion of the 142 kDa chain resulted in a decrease in size of approximately 14 kDa, indicating the presence of asparagine-linked units. Examination of normal and diabetic rat heart sections indicated that the latter contained abundant PAS-positive strands and nodules which corresponded to the distribution of anti type VI collagen reactivity. Moreover, immunoblots showed higher levels of Type VI collagen in diabetic than in normal heart extracts. Type VI collagen therefore appears to represent a major glycoprotein of myocardial extracellular matrix and to be implicated in diabetic cardiomyopathy.

Modeling 100,000-Year Climate Fluctuations in Pre-Pleistocene Time Series

A number of pre-Pleistocene climate records exhibit significant fluctuations at the 100,000-year (100-ky) eccentricity period, before the time of such fluctuations in global ice volume. The origin of these fluctuations has been obscure. Results reported here from a modeling study suggest that such a response can occur over low-latitude land areas involved in monsoon fluctuations. The twice yearly passage of the sun across the equator and the seasonal timing of perihelion interact to increase both 100-ky and 400-ky power in the modeled temperature field. The magnitude of the temperature response is sufficiently large to leave an imprint on the geologic record, and simulated fluctuations resemble those found in records of Triassic lake levels.

Cocaine, social behavior, and alcohol-solution drinking in monkeys

Eight group-living male monkeys received cocaine (0 to 3.0 mg/kg) individually or as a group. Cocaine suppressed social affiliative behaviors, eating, and drinking (of both alcohol and control solutions). It induced bizarre stereotypies, hypervigilance, panic-like fleeing, enhancement and then suppression of locomotion, and a seizure. Cocaine had little effect on aggressiveness or sexual behavior. Proportion of time spent lying or sitting changed significantly. Cocaine produced severe behavioral abnormality in this social setting.

Reinforcing breath carbon monoxide reductions in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) usually results from tobacco smoking. Smoking cessation slows COPD's progression, but few have studied anti-smoking treatments in COPD. In 3-month trials we paid lottery tickets during daily home visits to still-smoking COPD patients for reductions in breath carbon monoxide (CO), a measure of smoke intake. In our first protocol experimental patients received 0-3 tickets per day, depending upon the extent of CO reduction below pre-treatment baselines; yoked controls received the same number of tickets, but not contingent on CO. The protocol produced no change. In a second study patients were assigned a post-baseline quit-date, received nicotine gum, and were paid up to 5 tickets per night, but only for CO less than 10 parts per million (ppm). CO fell sharply as the intervention began, but gradually rose again. A third protocol added special reinforcement schedules for those who did not quit or relapsed (up to 20 tickets per night for CO less than 10 ppm). Daily CO concentrations fell from 27.1 parts per million (baseline mean) to 12.7 (intervention mean), but rapid increases followed the intervention. Few patients stopped smoking, but CO and cigarettes used per day significantly fell during Studies 2 and 3. Post-hoc analysis suggested only a small effect from gum.

Initiating ethanol drinking in a simian social group in a naturalistic setting

We examined in nine group-living, male Japanese Snow monkeys the initiation of alcohol-drinking behavior in an enriched environment where both social and nonsocial stimuli could influence drinking. The monkeys usually could move freely between an indoor shelter and a large outdoor corral, which contained three drinkometers. During daily 2-hr sessions in pre- and post-training periods (with food and water available ad libitum), the drinkometers held (on different days) Koolaid-saccharin, water, water with 5% ethanol, Koolaid-saccharin with 5% ethanol, or Koolaid-sucrose with acetic acid (matched in calories and palatability to Koolaid-saccharin with 5% ethanol). Between pre- and post-training periods was a long training period, in which Koolaid-saccharin with various ethanol concentrations was presented with the daily food ration in 2-hr drinking sessions. On other selected training days, water with 5% ethanol was presented. During training sessions some monkeys drank high doses; others did not. During the period of peak drinking, the daily mean ethanol consumption ranged among animals from 0.54-1.99 ml/kg. Blood ethanol concentrations then sometimes exceeded 100 mg/dl. During the post-training period, with return to ad libitum food and water, consumption declined from these peaks, but remained significantly higher than pretraining consumption; the ethanol solution was established as a reinforcer. Monkeys differed significantly in the extent of this pre/post increase. In both pre- and post-training periods, consumption was significantly greater when all three drinkometers operated, compared with only one. On pretraining days when only one drinkometer operated, more dominant animals drank significantly more than less dominant animals; this difference disappeared by the post-training period, as less dominant animals learned to use the drinkometers at times when the dominant animals eschewed the machines. Pretraining consumption did not predict (among animals) post-training consumption. Before, during, and after training, these animals drank less of both alcohol and control solutions than did members of another species, which we had studied in smaller indoor pens. We discuss possible explanations and implications.

Chronic pain and substance abuse: a pilot study of opioid maintenance

Recent reports suggest that opioid maintenance may be appropriate for treatment-resistant patients with chronic nonmalignant pain syndromes. However, a history of substance abuse is thought to be a contraindication for such treatment. We present a pilot study of a methadone maintenance-type treatment for patients with both chronic pain and substance abuse, evaluating the ability to attract and hold patients, the methodology for assessing change, and the potential problems and pitfalls. Weekly random urinalysis, weekly psychotherapy, and quarterly self-report tests of pain, mood, and function were used to evaluate change. Three out of 4 patients remained in treatment for 19-21 months, stopped needle use, and/or markedly decreased substance abuse, and appear to have improved functionally. Surprisingly, all 3 patients had significant psychopathology requiring treatment with psychotropic medication. This treatment may warrant further research.

Difficulties in a clinical application of methadone-dose contingency contracting

We review outcome of 14 methadone-maintenance patients who were offered a choice of administrative discharge or a methadone-dose contingency contract for continued drug abuse. In the three months before intervention, only 38% of urines were drug-free, while 55% were drug-free during the three-month intervention. Marked improvement occurred during the first month, while later the effect faded. Nine patients discontinued or reduced drug abuse, arriving at stable or fluctuating dose, and did not detoxify. Five others continued drug abuse, eventually reducing their methadone doses to zero. The procedure at least temporarily reduced drug abuse among the former group, but lack of uniformity in applying contingencies may have weakened the effect. Considering the spreading AIDS epidemic, we review the confusing literature on management of still-abusing methadone maintenance patients and suggest a protocol for their treatment.

Substance abuse among American Indians in an urban treatment program

Chart reviews were used to describe demographic and clinical characteristics of 68 urban American Indian people attending an Indian-oriented outpatient substance-abuse treatment program in Denver, Colorado, and to describe program staff's assessment of client's response to treatment. Alcohol and marijuana were the drugs abused most frequently. The program admitted about equal numbers of males and females; age averaged 24 years. Although Colorado has only Ute reservations, 49% of clients were Sioux, while none were Ute. Moreover, 87% of clients were not active in Indian religion and culture. Clients had low educational achievement and very low income. Few were in stable marriages. In comparison to counselors, clients underestimated the severity of their problems. By counselors' assessment, 78% of clients did not finish the program, and only two fully achieved the treatment goals. Areas for further clinical research are suggested.

Inexpensive outdoor enclosure for Japanese macaques used in biobehavioral research

For studies of alcohol self-administration in a monkey social group, we effectively and humanely enclosed nine Japanese macaques (Macaca fuscata) in an ellipse 32 x 40m, with a 1 m high chain-link fence surmounted by a 3 m curtain of electrically conductive nylon net. High-voltage brief-pulse charges prevent climbing on the net. Materials for this fence cost less than $14.50 per running meter. Weeds and grass grew freely within the ellipse, and seven dead trees interconnected with ropes permitted climbing and swinging. An open, roofed gazebo provided sun and rain shelter, and its single wall blocked the prevailing wind. Mouth activated drinkometer spouts in the corral supplied solutions for voluntary alcohol self-administration. Automatic counters informed an observer of exact doses consumed by each subject. Another observer recorded the frequency of occurrence of various social behaviors. A small kennel run, roofed over with chain-link fencing, connected the corral with a paddock-like, partially heated building, to and from which the monkeys usually had free access. It contained three interconnected chain-link pens. A raceway opening from the pens incorporated a squeeze cage used for weighing animals, drawing blood samples, or administering medications. This unique facility promotes the psychological well-being of research primates, which is being mandated by federal law.

Carbon monoxide assessment of smoking in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is a major, often fatal, drain on health-care resources. Most cases of COPD result from Tobacco Dependence, and smoking cessation slows COPD's progression. But there is very little information on treating Tobacco Dependence in COPD patients. In preparation for clinical trials using monetary payments to motivate reduced smoking, as assessed by breath carbon monoxide (CO) levels in COPD patients, we have addressed three issues. First, surveying 182 advanced COPD patients, we found that CO levels above 8 parts per million (ppm) were strongly associated with a self-report of current smoking, and that CO levels correlated neither with COPD severity, nor with age: about one-third of these patients were currently smoking. Second, among 12 still-smoking COPD patients serially observed for 8 h. CO half-life averaged about 6.5 h. Third, 8 patients reinforced with lottery tickets for CO reductions significantly reduced CO levels during 2 test weeks, mainly by deferring smoking before scheduled CO measurements.

Abrupt Climate Change and Extinction Events in Earth History

Slowly changing boundary conditions can sometimes cause discontinuous responses in climate models and result in relatively rapid transitions between different climate states. Such terrestrially induced abrupt climate transitions could have contributed to biotic crises in earth history. Ancillary events associated with transitions could disperse unstable climate behavior over a longer but still geologically brief interval and account for the stepwise nature of some extinction events. There is a growing body of theoretical and empirical support for the concept of abrupt climate change, and a comparison of paleoclimate data with the Phanerozoic extinction record indicates that climate and biotic transitions often coincide. However, more stratigraphic information is needed to precisely assess phase relations between the two types of transitions. The climate-life comparison also suggests that, if climate change is significantly contributing to biotic turnover, ecosystems may be more sensitive to forcing during the early stages of evolution from an ice-free to a glaciated state. Our analysis suggests that a terrestrially induced climate instability is a viable mechanism for causing rapid environmental change and biotic turnover in earth history, but the relation is not so strong that other sources of variance can be excluded.

Alcoholic-like drinking in simian social groups

We have developed two protocols for inducing sustained, high-dose, alcohol-reinforced, oral alcohol drinking among some members of Macaca nemestrina social groups. Both protocols initially co-present alcohol and the entire daily food supply in a 2-h daily drinking session, with a later return to continuous availability of food. One protocol presents unflavored aqueous alcohol to partially food-deprived subjects; the other compares the drinking of flavored alcohol solutions with the drinking of equally palatable isocaloric non-alcohol solutions when monkeys are not deprived of food. Daily high-dose drinking developed in both protocols, with biomedical changes similar to those of early human alcoholism. Daily drinking to blood alcohol concentrations above 100 mg/dl was sustained in some animals after return to baseline food conditions, and this may have been related to social rank within the groups. Alcohol reinforced drinking of the flavored solutions. Although food deprivation initially produced heavier drinking, drinking with the two protocols was equivalent after return to baseline feeding conditions. These procedures open new opportunities for examining combined social and genetic influences on alcoholic-like drinking.

Role of Seasonality in the Evolution of Climate During the Last 100 Million Years

A simple climate model has been used to calculate the effect of past changes in the land-sea distribution on the seasonal cycle of temperatures during the last 100 million years. Modeled summer temperatures decreased over Greenland by more than 10 degrees C and over Antarctica by 5 degrees to 8 degrees C. For the last 80 million years, this thermal response is comparable in magnitude to estimated atmospheric carbon dioxide effects. Analysis of paleontological data provides some support for the proposed hypothesis that large changes due to seasonality may have sometimes resulted in an ice-free state due to high summer temperature rather than year-round warmth. Such "cool" non-glacials may have prevailed for as much as one-third of the last 100 million years.

Hematologic malignancy in sickle cell disease: report of four cases and review of the literature

Hematologic malignancy has rarely been reported in adults with sickle cell disease. We describe four sickle cell patients (two with hemoglobin SC, two with hemoglobin SS) who developed hematologic malignancy (acute myeloblastic leukemia, multiple myeloma, malignant histiocytosis, and Hodgkin's disease). Three of the cases represent the first adult association between SC or SS hemoglobinopathy and the particular malignancy involved. Sickle hemoglobin does not appear to exert a protective effect against childhood hematologic malignancies, suggesting that better survival in sickle cell disease may be accompanied by an increased incidence of hematologic neoplasms in adulthood. Karyotypic analysis revealed alterations of chromosome 5 in two sickle cell patients with leukemia, raising the possibility of a chromosomal link between the two diseases. Further epidemiologic and cytogenetic studies are needed to define the relationship between hematologic malignancy and sickle cell disease.

Naltrexone-induced dysphoria in former opioid addicts

Naltrexone treatment, used to prevent relapse among former opioid addicts, is reported to have an extraordinary rate of noncompliance. Since activation of opioid receptors produces a sense of well-being, naltrexone's blockade of these receptors might produce dysphoria, which could contribute to noncompliance among addicts under treatment. To test this hypothesis, the authors administered naltrexone to four men who had been free of opioids for 9 to 44 months using a 6-week, placebo-controlled crossover design. One subject dropped out with abstinence-like symptoms, and two others reported mild but significantly greater dysphoria during naltrexone administration. The results suggest that naltrexone may induce mild dysphoria long after addicts stop using opioids.