Content area
Full Text
Abstract
Aims. To document patterns of cannabis use and dependence from late-adolescence through to the midtwenties; to describe perceived consequences of cannabis use among young people; and to consider policy implications of these findings.
Methods. This was a longitudinal study of the Dunedin Multidisciplinary Health and Development Study birth cohort with repeated measures of cannabis use at ages 18, 21 and 26 years.
Results. Twelve month prevalence rates of cannabis use (just over 50%) and dependence (just under 10%) remained stable between age 21 and 26 years, contrary to an expected decline. Cannabis dependence, as distinct from occasional use, was associated with high rates of harder drug use, selling of drugs and drug conviction. Cumulatively, almost 3/4 of our cohort had tried cannabis by age 26. Young people thought the risk of getting caught using cannabis was trivial, and that using cannabis had few negative social consequences.
Conclusions. The persistent high rates of cannabis use and dependence among young New Zealand adults raises important issues for policy makers. Current laws are not particularly effective in deterring use. Whereas occasional use does not appear to present a serious problem, cannabis dependence among users is a serious public health issue that warrants immediate action.
NZ Med J 2001; 114: 5447
Recent findings have demonstrated high rates of cannabis use and dependence among young New Zealanders1·2 but it is unknown if these high rates persist at older ages. This is important information because it has been suggested that heavy cannabis use is a temporary stage that begins to decline in the early twenties, reaching relatively low levels by the early thirties.3 These data have been interpreted as indicating that there is little long-term health risk associated with cannabis use.4·5 However, the Chen and Kandel report3 was based on Americans sampled 2 0 years ago and the findings may not apply to contemporary New Zealanders. If rates of cannabis use and dependence in New Zealand are found to remain high into the mid-twenties then important health and social/legal policy consequences may arise.6"8
This study documents change in patterns of use from adolescence to the mid-twenties. In addition, we investigated young people's perceptions of the consequences of using cannabis as these attitudes are likely to impact upon rates...