Genetic Epidemiology, Translational Neurogenomics, Psychiatric Genetics and Statistical Genetics Laboratories investigate the pattern of disease in families, particularly identical and non-identical twins, to assess the relative importance of genes and environment in a variety of important health problems.
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PMID
12533121
TITLE
Escalation of drug use in early-onset cannabis users vs co-twin controls.
ABSTRACT
CONTEXT NlmCategory: BACKGROUND
Previous studies have reported that early initiation of cannabis (marijuana) use is a significant risk factor for other drug use and drug-related problems.
OBJECTIVE NlmCategory: OBJECTIVE
To examine whether the association between early cannabis use and subsequent progression to use of other drugs and drug abuse/dependence persists after controlling for genetic and shared environmental influences.
DESIGN NlmCategory: METHODS
Cross-sectional survey conducted in 1996-2000 among an Australian national volunteer sample of 311 young adult (median age, 30 years) monozygotic and dizygotic same-sex twin pairs discordant for early cannabis use (before age 17 years).
MAIN OUTCOME MEASURES NlmCategory: METHODS
Self-reported subsequent nonmedical use of prescription sedatives, hallucinogens, cocaine/other stimulants, and opioids; abuse or dependence on these drugs (including cannabis abuse/dependence); and alcohol dependence.
RESULTS NlmCategory: RESULTS
Individuals who used cannabis by age 17 years had odds of other drug use, alcohol dependence, and drug abuse/dependence that were 2.1 to 5.2 times higher than those of their co-twin, who did not use cannabis before age 17 years. Controlling for known risk factors (early-onset alcohol or tobacco use, parental conflict/separation, childhood sexual abuse, conduct disorder, major depression, and social anxiety) had only negligible effects on these results. These associations did not differ significantly between monozygotic and dizygotic twins.
CONCLUSIONS NlmCategory: CONCLUSIONS
Associations between early cannabis use and later drug use and abuse/dependence cannot solely be explained by common predisposing genetic or shared environmental factors. The association may arise from the effects of the peer and social context within which cannabis is used and obtained. In particular, early access to and use of cannabis may reduce perceived barriers against the use of other illegal drugs and provide access to these drugs.
DATE PUBLISHED
2003 Jan 22-29
HISTORY
PUBSTATUS PUBSTATUSDATE
pubmed 2003/01/22 04:00
medline 2003/02/01 04:00
entrez 2003/01/22 04:00
AUTHORS
NAME COLLECTIVENAME LASTNAME FORENAME INITIALS AFFILIATION AFFILIATIONINFO
Lynskey MT Lynskey Michael T MT Queensland Institute of Medical Research, Brisbane, Queensland, Australia. mlynskey@matlock.wustl.edu
Heath AC Heath Andrew C AC
Bucholz KK Bucholz Kathleen K KK
Slutske WS Slutske Wendy S WS
Madden PA Madden Pamela A F PA
Nelson EC Nelson Elliot C EC
Statham DJ Statham Dixie J DJ
Martin NG Martin Nicholas G NG
INVESTIGATORS
JOURNAL
VOLUME: 289
ISSUE: 4
TITLE: JAMA
ISOABBREVIATION: JAMA
YEAR:
MONTH:
DAY:
MEDLINEDATE: 2003 Jan 22-29
SEASON:
CITEDMEDIUM: Print
ISSN: 0098-7484
ISSNTYPE: Print
MEDLINE JOURNAL
MEDLINETA: JAMA
COUNTRY: United States
ISSNLINKING: 0098-7484
NLMUNIQUEID: 7501160
PUBLICATION TYPE
PUBLICATIONTYPE TEXT
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Twin Study
COMMENTS AND CORRECTIONS
REFTYPE REFSOURCE REFPMID NOTE
CommentIn JAMA. 2003 Jul 16;290(3):329; author reply 330-1 12865366
CommentIn JAMA. 2003 Jul 16;290(3):329; author reply 330-1 12865368
CommentIn JAMA. 2003 Jan 22-29;289(4):482-3 12533129
CommentIn JAMA. 2003 Jul 16;290(3):329-30; author reply 330-1 12865367
CommentIn JAMA. 2003 Jul 16;290(3):330; author reply 330-2 12865369
GRANTS
GRANTID AGENCY COUNTRY
AA 12640 NIAAA NIH HHS United States
AA00277 NIAAA NIH HHS United States
AA07728 NIAAA NIH HHS United States
AA09022 NIAAA NIH HHS United States
AA10249 NIAAA NIH HHS United States
AA11998 NIAAA NIH HHS United States
DA 14363 NIDA NIH HHS United States
DA 14632 NIDA NIH HHS United States
DA00272 NIDA NIH HHS United States
DA12854 NIDA NIH HHS United States
GENERAL NOTE
KEYWORDS
MESH HEADINGS
DESCRIPTORNAME QUALIFIERNAME
Adolescent
Adult
Age of Onset
Cross-Sectional Studies
Female
Humans
Logistic Models
Male
Marijuana Abuse physiopathology
Mental Disorders physiopathology
Risk Factors physiopathology
Socioeconomic Factors physiopathology
Substance-Related Disorders epidemiology
Twins, Dizygotic epidemiology
Twins, Monozygotic epidemiology
SUPPLEMENTARY MESH
GENE SYMBOLS
CHEMICALS
OTHER ID's