AIMS To investigate the hypothesis that changes in cannabis prevalence among Dutch secondary school students (aged 12-17 years) were paralleled by shifts in the age of first cannabis use. DESIGN AND PARTICIPANTS Data were derived from five waves (1988, 1992, 1996, 1999 and 2003) of the Dutch National School Survey on Substance Use, a nationally representative cross-sectional study, with a tot...

AIM To describe the development of cannabis use in a birth cohort studied to the age of 21 years. METHODS The data were gathered during the Christchurch Health and Development Study. In this study a cohort of 1265 children born in the Christchurch urban region in mid 1997 has been studied to the age of 21 years. Information was gathered on patterns of cannabis use and dependence during the pe...

BACKGROUND Despite the high prevalence of cannabis use in schizophrenia, few studies have examined the potential relationship between cannabis exposure and brain structural abnormalities in schizophrenia. AIMS To investigate prefrontal grey and white matter regions in patients experiencing a first episode of schizophrenia with an additional diagnosis of cannabis use or dependence (n=20) compa...

Background: The political climate around Cannabis as a medicine is rapidly changing. Legislators are adopting policies regarding appropriate medical applications, while the paucity of research may make policy decisions around conditions for which Cannabis is an effective medicine difficult. Methods: An anonymous online survey was developed to query medical Cannabis users about the conditions th...

Cannabis is the most widely used illicit drug throughout the developed world and there is consistent evidence of heritable influences on multiple stages of cannabis involvement including initiation of use and abuse/dependence. In this paper, we describe the methodology and preliminary results of a large-scale interview study of 3,824 young adult twins (born 1972-1979) and their siblings. Cannab...

There is much debate about the impact of adolescent cannabis use on intellectual and educational outcomes. We investigated associations between adolescent cannabis use and IQ and educational attainment in a sample of 2235 teenagers from the Avon Longitudinal Study of Parents and Children. By the age of 15, 24% reported having tried cannabis at least once. A series of nested linear regressions w...

BACKGROUND Both environmental risk and genetic variation is believed to play a role in substance use. A candidate environmental variable is parenting. Recent studies have found support for the idea that the dopamine system affects the susceptibility to environmental influences. In the present study we will examine the interplay between effects of parental monitoring and the presence of the DRD4...

OBJECTIVES To determine risk factors of incident onset of use, abuse and dependence of cannabis in a community sample of adolescents and young adults. METHODS Risk factors were examined in a prospective longitudinal design across 4 years in a representative sample (N = 2,446) aged 14-24 at the outset of the study (EDSP). Patterns of DSM-IV defined cannabis use, abuse and dependence were asses...

Few studies have investigated the association between the social context of cannabis use and cannabis use disorder (CUD). This longitudinal study of college students aimed to: develop a social context measure of cannabis use; examine the degree to which social context is associated with the transition from non-problematic cannabis use to CUD; and, examine the association between social context ...

CONTEXT While there is a growing literature on the linkages between early subjective responses to nicotine and alcohol and later risks of nicotine or alcohol dependence, to date there has been no study of this issue in relation to cannabis. OBJECTIVE To examine the extent to which subjective responses to early (prior to the age of 16 years) cannabis use were associated with subsequent cannabi...