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PubMed2004

Impulsivity, negative expectancies, and marijuana use: a test of the acquired preparedness model.

According to the 'acquired preparedness model,' expectancies mediate the relationship between an impulsive personality style and alcohol use. The current study evaluated whether the model can also be applied to marijuana use. Estimated probabilities and subjective evaluations of personally expected marijuana effects, along with impulsivity and frequency of marijuana use, were assessed in 337 college undergraduates. Tests of mediation examining positive and negative marijuana expectancies showed negative expectancies to be a significant mediator for both males and females. That is, participants who were higher on impulsivity had fewer negative expectancies and in turn used more marijuana. This study provides evidence that the acquired preparedness model may help to explain marijuana use.

Adult↗

PubMedDate not supplied

Detection of marijuana use by oral fluid and urine analysis following single-dose administration of smoked and oral marijuana.

We compared oral fluid testing to urine testing in subjects who were administered single doses of marijuana by smoked and oral routes. Oral fluid specimens were collected with the Intercept DOA Oral Specimen Collection Device, screened for THC with the Cannabinoids Intercept MICRO-PLATE Enzyme Immunoassay (EIA) utilizing a 1.0-ng/mL cutoff concentration, and confirmed for THC by gas chromatography-tandem mass spectrometry (GC-MS-MS) with a 0.5-ng/mL cutoff concentration. Urine specimens were screened for 11-nor-carboxy-delta9-tetrahydrocannabinol (THCCOOH) by immunoassay utilizing a 50-ng/mL cutoff concentration and confirmed for THCCOOH by GC-MS with a 15-ng/mL cutoff concentration. Oral fluid specimens tested positive following smoked marijuana (N = 10) consecutively for average periods (+/-SEM; range) of 15 (+/-2; 1-24) and 13 h (+/-3; 1-24) by EIA and GC-MS-MS, respectively. The average THC detection times of the last oral fluid positive specimen following smoked marijuana by EIA and GC-MS-MS were 31 (+/-9; 1-72) and 34 h (+/-11; 1-72), respectively. In comparison to oral fluid, urine specimens generally tested negative for THCCOOH immediately after marijuana use. The average times to detection of the first urine specimen positive for THCCOOH by EIA and GC-MS were 6 (+/-2; 1-16) and 4 h (+/-1; 2-8), respectively. Urine specimens tested positive consecutively for average periods of 26 (+/-9; 2-72) and 33 h (+/-10; 4-72) for EIA and GC-MS, respectively. The average THCCOOH detection times of the last specimen by EIA and GC-MS were 42 (+/-10; 2-72) and 58 h (+/-6; 16-72), respectively. Considering the noninvasive nature of oral fluid collection and improved detection of recent marijuana use compared to urine testing, it was concluded that oral fluid testing for THC offers specific advantages over other means of marijuana testing when used in safety-sensitive testing programs.

Administration, Oral↗

PubMed2006

Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case-control study.

BACKGROUND: Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles. METHODS: Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age, gender, and neighborhood. Subjects were interviewed with a standardized questionnaire. The cumulative use of marijuana was expressed in joint-years, where 1 joint-year is equivalent to smoking one joint per day for 1 year. RESULTS: Although using marijuana for > or =30 joint-years was positively associated in the crude analyses with each cancer type (except pharyngeal cancer), no positive associations were observed when adjusting for several confounders including cigarette smoking. The adjusted odds ratio estimate (and 95% confidence limits) for > or =60 versus 0 joint-years was 1.1 (0.56, 2.1) for oral cancer, 0.84 (0.28, 2.5) for laryngeal cancer, and 0.62 (0.32, 1.2) for lung cancer; the adjusted odds ratio estimate for > or =30 versus 0 joint-years was 0.57 (0.20, 1.6) for pharyngeal cancer, and 0.53 (0.22, 1.3) for esophageal cancer. No association was consistently monotonic across exposure categories, and restriction to subjects who never smoked cigarettes yielded similar findings. CONCLUSIONS: Our results may have been affected by selection bias or error in measuring lifetime exposure and confounder histories; but they suggest that the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits.

Adenocarcinoma↗

PubMed1980

Psychosocial correlates of marijuana use and problem drinking in a national sample of adolescents.

Personality, environmental, and behavioral variables representing psychosocial risk factors for adolescent problem behavior were assessed in a 1974 national sample study of over 10,000 junior and senior high school students. Significant correlations were found with marijuana use, and the relationships held across differences in age, sex, and ethnic group membership. Greater involvement in marijuana use was associated with greater value on independence than on academic achievement, lower expectations for academic achievement, lesser religiosity, greater tolerance of deviance, less compatibility between friends and parents, greater influence of friends relative to parents, greater models and support for problem behavior, greater actual involvement in other problem behaviors such as drunkenness, and less involvement in conventional behavior such as attending church. Multiple regression analyses show that this pattern of psychosocial correlates accounts for over 50 per cent of the variation in marijuana use. The pattern is nearly identical to the pattern that accounts for problem drinking in these same adolescents. The similarity of the patterns of psychosocial risk, and the substantial correlations of marijuana use with problem drinking and with other problem behaviors, suggest that marijuana use is best seen as part of a syndrome of adolescent problem behavior. (Am J Public Health 70:604- 613,1980.)

Adolescent↗

PubMed1995

The effects of family structure and family relations on adolescent marijuana use.

The role of family structure in adolescence has been linked to a host of problem behaviors, including marijuana use. This paper investigates the relationship between family structure and marijuana use, and elaborates previous research by 1) exploring several intervening mechanisms that affect the relationship, and 2) examining the effects of a variety of family forms. Analyses of data from the National Youth Survey (1977-79) indicate that 1) a parental divorce or living with a stepparent decreases family attachment among adolescents; 2) attenuated family attachment and involvement increase the likelihood of associating with drug-using peers; and 3) less family involvement and increased associations with drug-using peers increase the probability of initiating marijuana use and elevate frequency of use.

Adolescent↗

PubMed2001

Marijuana use and HIV risk among adolescent offenders: the moderating effect of age.

PURPOSE: This study examined gender and age as potential moderators of the association between marijuana use and human immunodeficiency virus (HIV) risk among 272 adolescent offenders. METHODS: Analyses were based on biological and self-report measures of both marijuana use and HIV risk. RESULTS: Results revealed that the association between marijuana use and HIV risk was moderated by age but not gender across both biological and self-report measures. Specifically, marijuana use was associated with a higher occurrence of HIV risk among younger but not older adolescent offenders. IMPLICATIONS: These findings provide meaningful information that can be used to guide future research as well as interventions with adolescent offenders.

Adolescent↗

PubMed2005

Anxiety sensitivity interacts with marijuana use in the prediction of anxiety symptoms and panic-related catastrophic thinking among daily tobacco users.

The present investigation evaluated whether anxiety sensitivity interacted with marijuana use in relation to the prediction of panic-relevant variables among young adult tobacco smokers (n=265). Approximately 73% of the sample was composed of current marijuana smokers, with 78.5% of this sub-sample using marijuana more than once per week. As expected, after covarying cigarettes per day, alcohol use, and negative affectivity, the interaction between marijuana use and anxiety sensitivity predicted anxiety symptoms and agoraphobic cognitions. Partially consistent with prediction, the interaction between frequency of marijuana use and anxiety sensitivity predicted only anxiety symptoms. These results are discussed in relation to better understanding the potential role of regular marijuana use and anxiety sensitivity for panic-relevant emotional vulnerability among regular tobacco smokers.

Adolescent↗

PubMed2006

Prevalence of cocaine and marijuana use in the last trimester of adolescent pregnancy: socio-demographic, psychosocial and behavioral characteristics.

OBJECTIVE: To evaluate the prevalence of cocaine and marijuana use during the third trimester of pregnancy in a population of 1000 teenage women of a public hospital in São Paulo, Brazil using hair analysis in order to avoid underestimation of data that could happen by the use of self-report questionnaires and describe socio-demographic, psychosocial and behavioral characteristics of the drug users. RESULTS: Hair analysis has detected use of cocaine and/or marijuana in the third trimester of pregnancy in 6% of the patients: 4.0% used marijuana, 1.7% used cocaine and 3% used both drugs. They were about 17 years old, from low-income, poorly educated, unemployed, financially dependent and they had not planned the pregnancy. 10% of miscarriages have occurred in this population. CONCLUSION: This study shows the psychosocial impairment associated to teenage pregnancy and use of cocaine and marijuana during gestation by this low-income population with reliable data of prevalence obtained through hair analysis.

Adolescent↗

PubMed1991

Whatever happened to marijuana? Patterns of marijuana use in Australia, 1985-1988.

Although marijuana remains the most widely used illicit drug in the world, the rise of cocaine has eclipsed it as the main focus of scholarly research. It remains unclear, outside of the United States, to what extent marijuana use has declined in the late 1980s, and whether the risk for particular age and sex groups has changed. In this paper, national population survey data collected in 1985 and 1988 are used to examine changing patterns of marijuana use in Australia, with particular reference to adolescents. The results show that while adult experience of marijuana has changed little, female adolescent experience increased significantly during the period, while male adolescent experience declined. There is a strong association between marijuana use and other drug use, notably illicit drug. Tobacco use remains an important association with marijuana among adolescents.

Adolescent↗

PubMed1999

Platelet dense granule secretion and aggregation in adolescents with conduct disorder: effects of marijuana use.

BACKGROUND: We had previously reported a decrease in agonist-induced platelet dense granule secretion in blood samples from male adolescents with and without Conduct Disorder (CD). In an augmented sample, we have now employed multivariate modeling to examine the simultaneous effects of CD and regular monthly alcohol and marijuana use on both the dense granule secretion and aggregation phases of agonist-induced platelet responses. METHODS: Blood samples were obtained from adolescents with and without a CD diagnosis. Platelet dense granule secretion and aggregation responses to a variety of agonists were examined in the laboratory. RESULTS: Significant multivariate interactions of CD status with regular marijuana use were found for responses to collagen, ADP alone, and ADP plus 0.2 microgram. of serotonin. Responses in platelets from youth with CD, but without regular marijuana use differed from other subjects. Multivariate main effects of marijuana use alone on platelet responses to arachidonic acid and ADP plus 1.0 microgram. of serotonin were found. No effects of alcohol use were found. CONCLUSIONS: The results demonstrate an interaction between CD and the effects of chronic marijuana use for several agonists in this platelet model system, and further support the possibility of a variation in signal transduction mechanisms in CD.

Adenosine Diphosphate↗

PubMed1982

Marijuana metabolites in urine of man. X. Identification of marijuana use by detection of delta 9-tetrahydrocannabinol-11-oic acid using thin-layer chromatography.

Marijuana use can be determined by detecting delta 9-tetrahydrocannabinol-11-oic acid (THC-11-oic acid) in urine. For this, we describe a procedure for its chemical detection by using sequential thin-layer chromatography on a single plate for rapid isolation and identification. A volume of urine containing 50 mg of creatinine is concentrated by evaporation to 10 ml, the concentrate is enzymically hydrolyzed for 30 minutes and extracted with ether, and the extract is purified by treatment with NaHCO3, then chromatographed in an alkaline and an acidic solvent sequence. The plate is sprayed with Fast Blue Salt B, and THC-11-oic is identified by its characteristic mobility and its characteristic colour reaction. The sensitivity is 0.5 microgram. THC-11-oic acid has been detected in urines collected after the smoking of one standard cigarette containing 16-18 mg of delta 9-tetrahydrocannabinol and in 34 of the first 100 tests of spontaneously collected urines of patients in a hospital drug-abuse treatment program. Multiple samples are easily carried through this extraction procedure. Evaporative concentration takes about 20 min per sample, and the analysis of eight concentrated samples take about 5.5 h.

Cannabis↗

PubMed1981

Perspectives on marijuana use and abuse and recommendations for preventing abuse.

Survey research on levels of use and attitudes toward marijuana by youth indicate a consistently favorable attitude toward occasional, moderate use. Use of marijuana is contrasted with the use of alcohol and tobacco by youth. Research findings re the dangers of marijuana use are summarized. The inability of legislators and law enforcement personnel to control access to and use of marijuana, coupled with the high cost of our present legal response to the marijuana challenge, leads to recommending legalization of marijuana, as well as, developing a generic primary prevention program for marijuana abuse which features distinguishing "responsible use" from "abuse." Criteria for judging marijuana abuse are provided.

Adolescent↗

PubMed1999

Marijuana use and increased risk of squamous cell carcinoma of the head and neck.

Marijuana is the most commonly used illegal drug in the United States. In some subcultures, it is widely perceived to be harmless. Although the carcinogenic properties of marijuana smoke are similar to those of tobacco, no epidemiological studies of the relationship between marijuana use and head and neck cancer have been published. The relationship between marijuana use and head and neck cancer was investigated by a case-control study of 173 previously untreated cases with pathologically confirmed diagnoses of squamous cell carcinoma of the head and neck and 176 cancer-free controls at Memorial Sloan-Kettering Cancer Center between 1992 and 1994. Epidemiological data were collected by using a structured questionnaire, which included history of tobacco smoking, alcohol use, and marijuana use. The associations between marijuana use and head and neck cancer were analyzed by Mantel-Haenszel methods and logistic regression models. Controlling for age, sex, race, education, alcohol consumption, pack-years of cigarette smoking, and passive smoking, the risk of squamous cell carcinoma of the head and neck was increased with marijuana use [odds ratio (OR) comparing ever with never users, 2.6; 95% confidence interval (CI), 1.1-6.6]. Dose-response relationships were observed for frequency of marijuana use/day (P for trend <0.05) and years of marijuana use (P for trend <0.05). These associations were stronger for subjects who were 55 years of age and younger (OR, 3.1; 95% CI, 1.0-9.7). Possible interaction effects of marijuana use were observed with cigarette smoking, mutagen sensitivity, and to a lesser extent, alcohol use. Our results suggest that marijuana use may increase the risk of head and neck cancer with a strong dose-response pattern. Our analysis indicated that marijuana use may interact with mutagen sensitivity and other risk factors to increase the risk of head and neck cancer. The results need to be interpreted with some caution in drawing causal inferences because of certain methodological limitations, especially with regard to interactions.

Adult↗

PubMed2003

Marijuana use and injury events resulting in hospitalization.

PURPOSE: Information on the potential relation between marijuana use and the incidence of hospitalized injury is extremely limited. The purpose of this effort was to investigate the potential for this association. METHODS: A retrospective study was conducted in a large prepaid Northern California health care program cohort (n = 64,657) that completed baseline questionnaires about health behaviors, including marijuana use, and health status between 1979 and 1985. All injury hospitalizations through December 31, 1991, (n = 965) were identified and validated. RESULTS: Using Poisson regression modeling, increased rate-ratios and 95% confidence intervals were identified for all-cause injury hospitalizations for both men and women among current users (1.28; 1.01 to 1.61 and 1.37; 1.04 to 1.79, respectively) relative to nonusers, adjusted for age, cigarette and alcohol use, and other potential confounders. Increased rates of motor vehicle (1.96; 1.23 to 3.14), and assault (1.90, 1.16 to 3.15), injuries were identified among men who were current users; an increased rate of assault was suggestive in women (2.21; 0.92 to 5.19). CONCLUSIONS: Though the results must be viewed cautiously, they suggest that marijuana use may be independently associated with increased risk of hospitalized injury. Further study of the physiological and behavioral mechanisms is warranted [corrected].

Accidents, Traffic↗

PubMed2001

A twin study on sensation seeking, risk taking behavior and marijuana use.

The contribution of genetic and environmental factors to the covariation between risk-taking and marijuana use was assessed in adolescent twins. Genetic factors were found to significantly influence some traits (i.e. risk-taking attitude), while familial environmental factors were important for others (i.e. sexual promiscuity). For marijuana use, genetic and environmental factors were equally important; however, the association between risk taking and marijuana use may not be comparable for different behaviors. Results suggest that different etiological factors may underlie various risk taking traits which is relevant to both prevention efforts and attempts to identify genes involved in risk taking and shared genetic influences with substance use.

Adolescent↗

PubMed1993

Effects of chronic marijuana use on human cognition.

Impairments of human cognition and learning following chronic marijuana use are of serious concern, but have not been clearly demonstrated. To determine whether such impairments occurred, this study compared performance of adult marijuana users and non-users (N = 144 and N = 72, respectively) matched on intellectual functioning before the onset of drug use, i.e., on scores from standardized tests administered during the fourth grade of grammar school (Iowa Tests of Basic Skills). Subjects were given the twelfth grade versions of these tests (Iowa Tests of Educational Development) and other, computerized cognitive tests in successive test sessions. "Heavy" marijuana use (defined by use seven or more times weekly) was associated with deficits in mathematical skills and verbal expression in the Iowa Tests of Educational Development and selective impairments in memory retrieval processes in Buschke's Test. The retrieval impairments were restricted to words that were easy to visualize. Impairments depended on the frequency of chronic marijuana use, i.e., "light" and "intermediate" marijuana use (defined by use one to four and five to six times weekly, respectively) were not associated with deficits. Intermediate use was associated with superior performance in one condition ("fuzzy" concepts) of a Concept Formation test.

Adolescent↗

PubMed2003

Marijuana use and tridimensional personality traits among college students: a response to Hale, Whiteman, Muehl, and Faynberg.

Two important issues relevant to Hale, et al.'s 2003 study of temperament and self-reported marijuana use among college students are discussed. First, given the substantial heterogeneity within marijuana-using subject populations, it is key that studies of marijuana users' temperamental traits fully characterize such use across dimensions such as age of onset, quantity and frequency of lifetime, annual, and current use, and related social and health problems. Second, investigations should carefully address issues relating to the temporal ordering of marijuana use and temperamental traits such as novelty seeking and task persistence. Hale, et al., for example, were unable to determine whether self-reported marijuana use contributed to low scores on Persistence (as assessed by the Tridimensional Personality Questionnaire) or was a consequence of low Persistence, or both. Longitudinal studies of diverse populations of marijuana users who are carefully characterized with regard to substance use, comorbid psychiatric conditions, and temperamental traits will substantially increase understanding of the role of temperament and personality in the etiology of marijuana abuse and dependence.

Adult↗

PubMed1995

Inconsistencies in lifetime cocaine and marijuana use reports: impact on prevalence and incidence.

We evaluated inconsistencies in responses to questions about lifetime cocaine and marijuana use asked of nearly 10,000 respondents from the United States in the National Longitudinal Survey of Youth in 1984 and 1988. Our analyses showed that 14% of all responses on cocaine use and 17% of all responses on marijuana use were inconsistent in some way. The types of inconsistencies varied according to the substance; cocaine reports yielded more inconsistencies with regard to timing of first use, while for marijuana most of the inconsistencies were with respect to use disclosure. For both substances, lower level users were more likely to be inconsistent in their reports of drug use. Alternative methods for handling inconsistencies affected estimates of incidence and prevalence. Inconsistencies also varied according to respondent race/ethnicity. Implications of these findings for program evaluation are discussed.

Adolescent↗