Parental Marijuana Use Research Articles

Intergenerational Continuity and Discontinuity in Substance Use: The Role of Concurrent Parental Marijuana Use.

This study examines whether parental marijuana use that occurs during the life of a child impacts patterns of continuity and discontinuity in adolescent substance use among father-child dyads. The study uses data from 263 father-child-mother triads involved in the Rochester Youth Development Study (RYDS) and the Rochester Intergenerational Study (RIGS). We use a dual trajectory model is used to examine the research questions. Results suggest that both paternal and maternal marijuana use during the child's life increase the probability that a child will follow a moderate or high substance use trajectory during adolescence, beyond the risk incurred from paternal adolescent history of substance use. Some nuances related to the timing of concurrent parental marijuana use emerge across parent sex. Concurrent parental marijuana use predicts child's substance use beyond a parent's prior substance use history. The results highlight the important role of both caregivers in the explanation of patterns of discontinuity across generations, as well as the relevance of considering when the use occurred.

Assessment of Prescription Opioid Medical Use and Misuse Among Parents and Their Adolescent Offspring in the US

Limited information is available regarding the association between parental and adolescent medical prescription opioid use and misuse in the US. To examine the associations between parental and adolescent prescription opioid medical use and misuse. This cross-sectional, nationally representative study included 15 200 parent-adolescent dyads from the annual 2015-2017 National Survey on Drug Use and Health. Data were collected from January 6, 2015, to December 20, 2017, and analyzed from October 4, 2019, to October 15, 2020. Parental past 12-month exclusive medical prescription opioid use and any misuse (ie, using without a prescription or in any way not directed by a physician). Adolescent past 12-month medical prescription opioid use or misuse. Multivariable regressions estimated associations between parental and offspring medical prescription opioid use or misuse, controlling for sociodemographic and psychosocial variables. Respondents included 9400 mother-child and 5800 father-child dyads in the same household; children were aged 12 to 17 years (52.8% male; mean [SD] age, 14.5 [1.7] years). Controlling for other factors, parental medical prescription opioid use was associated with adolescent prescription opioid medical use (adjusted odds ratio [aOR], 1.28; 95% CI, 1.06-1.53) and misuse (aOR, 1.53; 95% CI, 1.07-2.25), whereas parental misuse was not. Parental medical prescription stimulant use was associated with adolescent medical prescription opioid use (aOR, 1.40; 95% CI, 1.02-1.91). Parental marijuana use (aOR, 1.84; 95% CI, 1.13-2.99), parent-adolescent conflict (aOR, 1.26; 95% CI, 1.05-1.52), and adolescent depression (aOR, 1.75; 95% CI, 1.26-2.44) were associated with adolescent prescription opioid misuse. Adolescent delinquency (aOR, 1.55; 95% CI, 1.38-1.74) and perceived schoolmates' drug use (aOR, 2.87; 95% CI, 1.95-4.23) were also associated with adolescent misuse and more weakly with medical use (aORs, 1.13 [95% CI, 1.05-1.22] and 1.61 [95% CI, 1.32-1.96], respectively). Youth use of prescription opioids is in part a structural/environmental issue. The findings of this study suggest that parental medical prescription opioid use is associated with offspring prescription opioid use, whereas parental misuse is not. Restricting physicians' opioid prescribing to parents is a crucial public health goal. In addition, parents could be educated on the risks of their prescription opioid use for offspring and on practices to mitigate risk, including safe medication storage and disposal. Screening for parental prescription opioid use could be part of pediatric practice. Addressing adolescent mental health could also reduce adolescent prescription opioid misuse.

An intergenerational investigation of the associations between parental marijuana use trajectories and child functioning.

Diverse patterns of life-course marijuana use may have differential health impacts for the children of users. Data are drawn from an intergenerational study of 426 families that included a parent, their oldest biological child, and (where appropriate) another caregiver who were interviewed 10 times from 2002 to 2018; the current study used data from 380 families in waves 6-10. Analyses linked parent marijuana use trajectories estimated in a previous publication (Epstein et al., 2015) to child marijuana, alcohol, and nicotine use; promarijuana norms; internalizing; externalizing; attention problems; and grades using multilevel modeling among children ages 6 to 21. Four trajectories had been found in the previous study: nonuser, chronic, adolescent-limited, and late-onset. Results indicate that children of parents in the groups that initiated marijuana use in adolescence (chronic and adolescent-limited) were most likely to use substances. Children of parents in the late-onset group, where parents initiated use in young adulthood, were not at increased risk for substance use but were more likely to have attention problems and lower grades. Results held when parent current marijuana use was added to the models. Implications of this work highlight the importance of considering both current use and use history in intergenerational transmission of marijuana use, and the need to address parent use history in family based prevention. Prevention of adolescent marijuana use remains a priority. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Intergenerational marijuana use: A life course examination of the relationship between parental trajectories of marijuana use and the onset of marijuana use by offspring.

Prior research documents intergenerational (IG) continuity in marijuana use, with most work adopting a life course perspective. Incorporating a methodology that allows for the measurement of "patterns of behavior" instead of singular aspects of parent marijuana use (e.g., age of onset or frequency at any one age or ages), we investigated the simultaneous effects of parental age of onset, frequency, and duration of marijuana use across 3 periods of the life course (i.e., adolescence, emerging adulthood, and adulthood) on the timing of first marijuana use among offspring. Using prospective data from 2 companion studies, the Rochester Youth Development Study and the Rochester Intergenerational Study, we used group-based trajectory models to estimate trajectories (or patterns) of parental marijuana use spanning ages 14 to 31 among a birth cohort of 462 parents. We then examined the relationship between parental trajectories of marijuana use and the timing of the onset of marijuana use through age 25 among firstborn offspring. Both late-onset persistent use by parents and increasing chronic use spanning adolescence to adulthood by parents were associated with an increased likelihood of onset of marijuana use among offspring. The results underscore the importance of patterns of marijuana use for IG continuity in contrast to singular measures (e.g., age of onset among parents), which can obfuscate important IG patterns of continuity. Prevention and intervention programs should consider the entire history of parent use to better identify children most at risk for the onset of marijuana use in adolescence and emerging adulthood. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Evaluating the effect of retail marijuana legalization on parent marijuana use frequency and norms in U.S. States with retail marijuana legalization

ObjectivesTo examine post-retail marijuana legalization (RML) change in marijuana use frequency and pro-marijuana norms among parents. MethodsThe Intergenerational Study, a longitudinal panel of parents (N = 668) and children, followed participants from 2002 to 2018, when parents were 27 and 43 years old, respectively. Three quarters of participants (74%) lived in an RML state and 142 (21%) had used marijuana in the 8 years prior to RML. Piecewise growth modelling compared pre- and post-RML slopes of use frequency and pro-marijuana norms. ResultsFrequency of use and pro-marijuana norms increased following legalization in both RML and non-RML states, though norms rose significantly faster in RML states. Growth in use was primarily driven by new users of marijuana. There were no differences in frequency of marijuana use or pro-marijuana norms by race/ethnicity, gender, or education. ConclusionsAn increase in marijuana use frequency associated with RML among parents poses risk to both parents' well-being and the health of their children. A faster pace of increase in pro-marijuana norms in RML states may signal continued increases in use in the future.

Initial use of tobacco or marijuana and later use profiles in young adults.

INTRODUCTIONGiven the relatively limited literature regarding risk factors for progression of alternative tobacco and marijuana use, this study examined initially-used tobacco or marijuana products and psychosocial risk factors such as adverse childhood events (ACEs), mental health (depression, ADHD), and parental substance use, in relation to young adult lifetime and current (past 30-day) tobacco and marijuana use.METHODSUsing cross-sectional data from a 2014–2016 study of 3418 young adult college students in Georgia, we analyzed lifetime and current use of various tobacco products (cigarettes, cigar products, smokeless tobacco, e-cigarettes, hookah) and marijuana among lifetime tobacco or marijuana users (N=1451) in relation to initially-used product as well as sociodemographic characteristics and psychosocial risk factors.RESULTSMultivariable analyses indicated that more products ever used correlated with cigarettes being first used (vs cigars, B=-0.66; e-cigarettes, OR=-1.33; hookah, B=-0.99; and marijuana, B=-1.05; p<0.001), as well as being older (B=0.06), male (B=-0.72) and White (vs Black, B=-0.30; or Asian, B=-0.60), more adverse childhood events (ACEs, B=0.07), and parental marijuana use (B=0.47; p<0.05). Currently-used products correlated with cigarettes being first used (vs cigars, B=-0.18; e-cigarettes, B=-0.37; and hookah, B=-0.18; p<0.05), being younger (B=-0.04), male (B=-0.15), more depressive symptoms (B=0.01), and parental marijuana use (B=0.40; p<0.05). Current cigarette, smokeless tobacco, hookah and marijuana use demonstrated specificity to initially-used products.CONCLUSIONSInitially-used products, specifically cigarettes, with well-documented and communicated risks, correlated with using more products subsequently among young adults, underscoring needed research on such risks and risk communication, and early intervention strategies.

Parental Influences on Adolescent Major Depressive Symptoms and Marijuana Use

Adolescent depression is associated with many negative outcomes, including elevated marijuana use. Although parental influences on adolescent depressive symptoms and marijuana use have been examined independently, their interrelation remains understudied. The current research investigates the hypothesis that lower levels of parental monitoring and warmth are inversely associated with adolescent depressive symptoms and marijuana use. A path analytic approach (N = 12,115) on data from a representative US sample indicated depressive symptoms had an indirect effect on the relationship between parental warmth (p < .001), monitoring (p = .013), and adolescent marijuana use. Exploring relationships grouped by respondents’ age (12–14 and 15–17 years, respectively) revealed minor differences. Depressive symptoms had significant indirect effects on parental warmth and marijuana use (both p < .001) and on parental monitoring and marijuana use (both p < .05). Parental influences appear to play an important role in marijuana use among adolescents with depressive symptoms.

Study: Elevated risk of substance use if parents use marijuana

Last month, JAMA Network Open published a study indicating that recent and past parental marijuana use confers a heightened risk for use of marijuana — and other substances — by their adolescent and young adult offspring who live in the same household. The article from the Substance Abuse and Mental Health Services Administration (SAMHSA), the National Institute on Drug Abuse and McLean Hospital is in line with federal anti‐marijuana policy (marijuana is still illegal under federal law, although states have legalized it, both recreationally, in some cases, and medically, in more).

Associations of Parental Marijuana Use With Offspring Marijuana, Tobacco, and Alcohol Use and Opioid Misuse

Marijuana use is increasing among adults and often co-occurs with other substance use; therefore, it is important to examine whether parental marijuana use is associated with elevated risk of substance use among offspring living in the same household. To examine associations of parental marijuana use with offspring marijuana, tobacco, and alcohol use and opioid misuse. This cross-sectional study used survey data from the 2015 through 2018 National Surveys on Drug Use and Health (NSDUH), which provide nationally representative data on adolescents or young adults living with a parent (the mother or the father). Annual average percentages were based on survey sampling weights. Final analyses were conducted September 21 through 23, 2019. Parental marijuana use status. Offspring self-reported use of marijuana, tobacco, or alcohol or misuse of opioids. Survey respondents included 24 900 father-offspring or mother-offspring dyads sampled from the same household. Among mothers living with adolescent offspring, 8.2% (95% CI, 7.3%-9.2%) had past-year marijuana use, while 7.6% (95% CI, 6.2%-9.2%) of mothers living with young adult offspring had past-year marijuana use. Among fathers living with adolescent offspring, 9.6% (95% CI, 8.5%-10.8%) had past-year marijuana use, and 9.0% (95% CI, 7.4%-10.9%) of fathers living with young adult offspring had past-year marijuana use. Compared with adolescents whose mothers never used marijuana, adjusted relative risk (ARR) of past-year marijuana use was higher among those whose mothers had lifetime (without past-year) marijuana use (ARR, 1.3; 95% CI, 1.1-1.6; P = .007), less than 52 days of past-year marijuana use (ARR, 1.7; 95% CI, 1.1-2.7; P = .02), or 52 days or more of past-year marijuana use (ARR, 1.5; 95% CI, 1.1-2.2; P = .02). Compared with young adults whose mothers never used marijuana, adjusted risk of past-year marijuana use was higher among those whose mothers had lifetime (without past-year) marijuana use (ARR, 1.4; 95% CI, 1.1-1.7; P = .001), less than 52 days of past-year marijuana use (ARR, 1.5; 95% CI, 1.0-2.3; P = .049), or 52 days or more of past-year marijuana use (ARR, 1.8; 95% CI, 1.3-2.5; P = .002). Compared with adolescents whose fathers never used marijuana, adolescents whose fathers had less than 52 days of past-year marijuana use were more likely to use marijuana (ARR, 1.8; 95% CI, 1.2-2.7; P = .006). Compared with young adults whose fathers never used marijuana, young adults whose fathers had 52 days or more of past-year marijuana use were more likely to use marijuana (ARR, 2.1; 95% CI, 1.6-2.9; P < .001). Compared with their peers whose parents never used marijuana and after adjusting for covariates, the adjusted risk of past-year tobacco use was higher among adolescents whose mothers had lifetime marijuana use (ARR, 1.3; 95% CI, 1.0-1.6; P = .03), less than 52 days of past-year marijuana use (ARR, 1.5; 95% CI, 1.0-2.1; P = .04), or 52 days or more of past-year marijuana use (ARR, 1.6; 95% CI, 1.1-2.3; P = .03); adolescents whose fathers had lifetime marijuana use (ARR, 1.5; 95% CI, 1.1-1.9; P = .004) or 52 days or more of past-year marijuana use (ARR, 1.8; 95% CI, 1.2-2.7; P = .006); young adults whose mothers had lifetime marijuana use (ARR, 1.2; 95% CI, 1.0-1.4; P = .04); and young adults whose fathers had 52 days or more of past-year marijuana use (ARR, 1.4; 95% CI, 1.0-1.9; P = .046). Compared with their peers whose parents had no past marijuana use and after adjusting for covariates, risk of past-year alcohol use was higher among adolescents whose mothers had lifetime marijuana use (ARR, 1.2; 95% CI, 1.1-1.4; P = .004), less than 52 days of past-year marijuana use (ARR, 1.5; 95% CI, 1.2-1.9; P = .002), or 52 days or more of past-year marijuana use (ARR, 1.3; 95% CI, 1.0-1.7; P = .04). After adjusting for covariates, parental marijuana use was not associated with opioid misuse by offspring. In this cross-sectional study, parental marijuana use was associated with increased risk of substance use among adolescent and young adult offspring living in the same household. Screening household members for substance use and counseling parents on risks posed by current and past marijuana use are warranted.

The Complicated Relationship Between Marijuana Use and Parenting

The intersection between marijuana and parenting is both highly controversial and largely unexplored. Despite the trend of legalization (medicinal and recreational) across the country, there is a widening discrepancy between criminal laws and child welfare policies. Even in states where marijuana is recreationally legal, a parent might still be charged with child abuse or neglect as a result of his or her marijuana use. Although second-hand marijuana smoke has proven to be a relatively low risk of harm to children, other areas of concern have not been adequately studied, such as the effects of marijuana use during pregnancy and/or breastfeeding. Despite the lack of reliable scientific studies on the impact of ingestion by children, some initial studies have shown a marked increase in frequency of accidental ingestions and resulting hospital treatment in states that have legalized marijuana. The palatability and attractiveness of “edibles” is likely the cause of this measurable and dramatic increase. Overall, parental marijuana use has been inadequately studied by science, but some reliable data is available which could be used overhaul existing children’s services policies.

Men's misuse of prescription opioids from early to middle adulthood: An examination of developmental and concurrent prediction models.

The prevalence of misuse of prescription opioids across adulthood and the associations of such misuse with symptoms of psychopathology and use of other substances were examined for an at-risk community sample of men. For a longitudinal study of boys (N = 206) followed to adulthood, misuse of prescription opioids was assessed on 13 occasions from ages 20-21 years to 37-38 years. Prediction of misuse was examined from prospectively assessed risk factors in 3 models: (a) parental substance use during the men's adolescence; (b) the men's own risk behaviors in adolescence-delinquent behavior, depressive symptoms, and use of tobacco, alcohol, marijuana, and opioids; and (c) within- and between-individual effects of the men's risk behaviors during adulthood. Opioid misuse was reported by 29% of men. After accounting for effects of age and considered individually, parent marijuana use and all of the adolescent and adult risk factors (except adolescent depressive symptoms) were significant between-individual predictors of opioid misuse. Furthermore, within-individual prediction was significant for adult delinquency and alcohol use after accounting for increases in opioid misuse with age. When risk factors were tested simultaneously, men's adult delinquency and use of marijuana and tobacco remained significant between-individual predictors, whereas no parental or adolescent risk factors remained significant in these models. Both adolescent and adult risk factors were examined that predicted adult opioid misuse. Preventing adolescent problem behavior and using such histories to inform screening for misuse risk in adulthood may reduce the burden of the opioid crisis. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Understanding the Role of Parental Opiate or Marijuana Use in Child Welfare Substantiation Decisions

Parental drug misuse is a risk factor that child welfare workers must consider during investigations of alleged maltreatment. Little is known, however about how workers view substance use, particularly for substances like marijuana and prescription opioids which are used legally in some circumstances but not in others. Qualitative data from a mixed-methods web-based survey of 562 workers in child welfare-related fields were used to examine the ways in which parental substance use influenced decision-making. Findings suggest that the legality of the substance, how the substance is used around children, and the nexus between substance use and parenting were influential in caseworker decisions, which can inform future educational and policy efforts.

Associations Between Parental and Grandparental Marijuana Use and Child Substance Use Norms in a Prospective, Three-Generation Study

PurposeUsing prospective longitudinal data from three generations, this study seeks to test whether and how parent and grandparent marijuana use (current and prior) predicts an increased likelihood of child cigarette, alcohol, and marijuana use. MethodsUsing multilevel modeling of prospective data spanning three generations (n = 306 families, children ages 6–22), this study tested associations between grandparent (G1) and parent (G2) marijuana use and child (G3) past-year cigarette, alcohol, and marijuana use. Analyses tested whether G3 substance-related norms mediated these associations. Current G1 and G2 marijuana use was examined, as was G2 high school and early adult use and G1 marijuana use when G2 parents were in early adolescence. Controls included G2 age at G3 birth, G2 education and depression, and G3 gender. ResultsG2 current marijuana use predicted a higher likelihood of G3 alcohol and marijuana use but was not related to the probability of G3 cigarette use. G3's perceptions of their parents' norms and G2 current marijuana use both contributed independently to the likelihood of G3 alcohol and marijuana use when included in the same model. G3 children's own norms and their perceptions of friends' norms mediated the link between G2 current marijuana use and G3 alcohol and marijuana use. ConclusionsResults are discussed in light of the growing trend toward marijuana legalization. To the extent that parent marijuana use increases under legalization, we can expect more youth to use alcohol and marijuana and to have norms that favor substance use.

Contextual risks linking parents’ adolescent marijuana use to offspring onset

ObjectiveWe studied the extent to which parent marijuana use in adolescence is associated with marijuana use onset in offspring through contextual family and peer risks. MethodFathers assessed (n=93) since childhood, their 146 offspring (n=83 girls), and offspring's mothers (n=85) participated in a longitudinal study. Using discrete-time survival analysis, fathers’ (prospectively measured) and mothers’ (retrospective) adolescent marijuana use was used to predict offspring marijuana use onset through age 19 years. Parental monitoring, child exposure to marijuana use, peer deviance, peer marijuana use, and perceptions of parent disapproval of child use were measured before or concurrent with onset. ResultsParents’ adolescent marijuana use was significantly associated with less monitoring, offspring alcohol use, the peer behaviors, exposure to adult marijuana use, and perceptions of less parent disapproval. Male gender and the two peer behaviors were positively associated with children's marijuana use onset, controlling for their alcohol use. Parents’ adolescent marijuana use had a significant indirect effect on child onset through children's deviant peer affiliations and a composite contextual risk score. ConclusionsParents’ histories of marijuana use may contribute indirectly to children's marijuana use onset through their influence on the social environments children encounter; specifically, those characterized by more liberal use norms, exposure to marijuana use and deviant and marijuana-using peers, and less adult supervision. Given that alcohol use onset was controlled, findings suggest that the contextual factors identified here confer unique risk for child marijuana use onset.

Heterogeneity in men's marijuana use in the 20s: adolescent antecedents and consequences in the 30s.

Adolescent psychopathology is commonly connected to marijuana use. How changes in these adolescent antecedents and in adolescent marijuana use are connected to patterns of marijuana use in the 20s is little understood. Another issue not clearly understood is psychopathology in the 30s as predicted by marijuana use in the 20s. This study sought to examine these two issues and the associations with marijuana disorder diagnoses using a longitudinal data set of 205 men with essentially annual reports. Individual psychopathology and family characteristics from the men's adolescence were used to predict their patterns of marijuana use across their 20s, and aspects of the men's psychopathology in their mid-30s were predicted from these patterns. Three patterns of marijuana use in the 20s were identified using growth mixture modeling and were associated with diagnoses of marijuana disorders at age 26 years. Parental marijuana use predicted chronic use for the men in adulthood. Patterns of marijuana use in the 20s predicted antisocial behavior and deviant peer association at age 36 years (controlling for adolescent levels of the outcomes by residualization). These findings indicate that differential patterns of marijuana use in early adulthood are associated with psychopathology toward midlife.

Parental absence and marijuana use among American youth in the latest NSDUH

Parental absence and marijuana use among American youth in the latest NSDUH

Family and parenting characteristics associated with marijuana use by Chilean adolescents.

ObjectiveFamily involvement and several characteristics of parenting have been suggested to be protective factors for adolescent substance use. Some parenting behaviors may have stronger relationships with adolescent behavior while others may have associations with undesirable behavior among youth. Although it is generally acknowledged that families play an important role in the lives of Chilean adolescents, scant research exists on how different family and parenting factors may be associated with marijuana use and related problems in this population which has one of the highest rates of drug use in Latin America.MethodsUsing logistic regression and negative binomial regression, we examined whether a large number of family and parenting variables were associated with the possibility of Chilean adolescents ever using marijuana, and with marijuana-related problems. Analyses controlled for a number of demographic and peer-related variables.ResultsControlling for other parenting and family variables, adolescent reports of parental marijuana use showed a significant and positive association with adolescent marijuana use. The multivariate models also revealed that harsh parenting by fathers was the only family variable associated with the number of marijuana-related problems youth experienced.ConclusionOf all the family and parenting variables studied, perceptions of parental use of marijuana and harsh parenting by fathers were predictors for marijuana use, and the experience of marijuana-related problems. Prevention interventions need to continue emphasizing the critical socializing role that parental behavior plays in their children’s development and potential use of marijuana.

Protecting against intergenerational problem behavior: Mediational effects of prevented marijuana use on second-generation parent–child relationships and child impulsivity

Background The aims of the study were to identify pathways from parent marijuana use to child problem behavior and parent–child relationships, and to evaluate whether effects of an earlier prevention program delivered to parents when they themselves were early adolescents would have a protective effect on these relationships one generation later. Methods Structural equation models were applied to the data of a second-generation study of a drug abuse prevention trial. Models assessed whether there were sustained marijuana prevention effects on adults who had at least one school-age child at the end of the emerging adulthood period (age 26, n = 257), and whether these effects mediated subsequent parent–child relationships and child impulsivity when parents were between the ages of 28 and 34. Results Participants originally assigned to the program group used significantly less marijuana in early adulthood than did controls. In turn, parental marijuana use was positively related to child impulsivity and negatively to parental warmth, but not significantly related to parental aggression. Conclusions Results suggest both a direct relationship from parental marijuana use to child impulsivity, as well as indirect relationships through parent–child interactions. Results also strongly support a role for early adolescent prevention programs for drug use, both for participants’ own long-term benefit, as well as for the benefit of their future children.

Predictors of Rebellious Behavior in Childhood

This study assesses the interrelationships among several sets of variables and rebellious behavior in a sample of Puerto Rican and African American elementary school-aged children. The independent sets of variables (domains) were child personality attributes, parental attributes, including parental marijuana use, peer factors, school environment, and ethnic identification and discrimination. The dependent or outcome variable was children's rebellious behavior. Children and their mothers were interviewed in their homes. Pearson correlations and hierarchical multiple regression analyses were used to assess the extent to which the independent variables were related to the children's rebellious behavior. Each of the domains was associated with children's rebellious behavior without control on the remaining domains. With control on the remaining domains, child personality accounted for the most variance in childhood rebellious behavior. With control on child personality, only the school environment remained significant. Children with personality traits that are associated with rebellious behavior may have parents who exhibit antisocial behavior and use marijuana. Furthermore, these children may be at risk for other problem behaviors, including legal drug use, and would benefit from interventions which address primarily their personality characteristics, but also their school environments.

Parental marijuana use and risk of childhood acute myeloid leukaemia: a report from the Children's Cancer Group (United States and Canada)

The aetiology of childhood acute myeloid leukaemia (AML) is largely unknown. Maternal marijuana use just before, or during pregnancy has been previously associated with childhood AML. This case-control investigation formally tested the hypothesis that parental marijuana use increases the risk of childhood AML in offspring. Incident cases of AML <18 years of age, diagnosed between 1989 and 1993, and registered with the Children's Cancer Group (a paediatric clinical co-operative group), were eligible for inclusion. Control children were selected via random digit dialling and individually matched 1:1 to cases on age, race and residential location, except for rare morphological subtypes that were matched 1:2. Parental telephone interviews were conducted to determine exposure and covariate information. Conditional logistic regression was used to estimate matched odds ratios (OR) and 95% confidence intervals [CI] adjusted for household income, parental education and parental age. The analysis included 517 cases and 610 matched controls. A series of sensitivity analyses examined the potential for recall bias. Ever lifetime use of marijuana by mothers was not associated with childhood AML [OR = 0.89; 95% CI = 0.66, 1.19]. Maternal marijuana use any time during the 3 months before, or during pregnancy was inversely associated with childhood AML [OR = 0.43; 95% CI = 0.23, 0.80]. Paternal use during the same time period was not associated with risk. Assuming a large degree of differential exposure misclassification was present, the corrected ORs ranged between 0.82 and 1.40. The previously reported positive association between maternal marijuana use before or during pregnancy and childhood AML was not confirmed. The decreased ORs observed in this study may be due to recall bias assuming plausibly low values of sensitivity.