Fergusson D M, Horwood L J
Department of Psychological Medicine, Christchurch School of Medicine, New Zealand.
Addiction. 2000 Apr;95(4):505-20. doi: 10.1046/j.1360-0443.2000.9545053.x.
To examine the relationship between cannabis use in adolescence and the onset of other illicit drug use.
Data were gathered over the course of a 21-year longitudinal study of a birth cohort of 1265 New Zealand children. Measures analysed included: (a) frequency of cannabis use and other illicit drugs from 15-21; (b) family, social, educational and behavioural backgrounds of cohort members prior to 15; and (c) adolescent life-style variables.
(i) By 21, nearly 70% of cohort members and used cannabis and 26% had used other illicit drugs. (ii) In all but three cases, the use of cannabis had preceded the use of illicit drugs. (iii) Those using cannabis on more than 50 occasions a year had hazards of other illicit drug use that were 140 times higher than non-users. (iv) After adjustment for covariate factors, including childhood factors, family factors and adolescent life-style factors, cannabis use remained strongly related to the onset of other forms of illicit drug use. Those using cannabis on more than 50 occasions per year had hazards of other illicit drug use that were 59.2 times higher than non-users.
Findings support the view that cannabis may act as a gateway drug that encourages other forms of illicit drug use. None the less, the possibility remains that the association is non-causal and reflects factors that were not adequately controlled in the analysis.
研究青少年使用大麻与开始使用其他非法药物之间的关系。
数据收集自一项对1265名新西兰儿童出生队列进行的为期21年的纵向研究。分析的测量指标包括：（a）15至21岁期间使用大麻和其他非法药物的频率；（b）队列成员15岁之前的家庭、社会、教育和行为背景；以及（c）青少年生活方式变量。
（i）到21岁时，近70%的队列成员使用过大麻，26%使用过其他非法药物。（ii）除三例之外，在所有情况中，使用大麻都先于使用非法药物。（iii）每年使用大麻超过50次的人使用其他非法药物的风险比不使用者高140倍。（iv）在对包括儿童因素、家庭因素和青少年生活方式因素在内的协变量因素进行调整之后，使用大麻仍然与开始使用其他形式非法药物密切相关。每年使用大麻超过50次的人使用其他非法药物的风险比不使用者高59.2倍。
研究结果支持以下观点，即大麻可能充当一种诱导性毒品，促使使用其他形式的非法药物。尽管如此，仍有可能这种关联并无因果关系，只是反映了分析中未得到充分控制的因素。
