Alcohol Is Not the Gateway to Hard Drug Abuse
Golub, Andrew Lang, Johnson, Bruce D., Journal of Drug Issues
Much prior research has found that alcohol and/or tobacco use in early adolescence typically precedes marijuana use which typically precedes any hard drug use and abuse. This finding has been often misinterpreted as suggesting that use of alcohol somehow "causes" subsequent hard drug abuse. This perspective has lead to the simplistic policy position that preventing alcohol use among youths will eventually solve the broader problem of substance abuse. This paper reviews the ample evidence which refutes this claim and encourages those involved with policy development not to oversimplify the challenges and problems facing youths.
Does use of alcohol by youths lead them to abuse hard drugs such as cocaine, crack and heroin? This question is ambiguous because the phrase "leads to" has two distinct meanings: precedes and causes. A wealth of studies document that initial use of alcohol often occurs in adolescence while use of illicit drugs typically starts in the later teens. In this narrow temporal sense, use of alcohol often precedes any use of illicit drugs. On the other hand, policy statements concerning alcohol and drug abuse prevention frequently employ the phrase "leads to" to suggest that use of alcohol effectively "causes" subsequent hard drug abuse. These statements often mistakenly refer to the gateway theory to establish the "scientific" credibility of their claim.
Kandel (1978) whose seminal work is widely acknowledged for pioneering research on the gateway theory suggests that the process leading to the possible abuse of hard drugs typically follows a series of stages from non-use to use of alcohol and/or tobacco, then to marijuana and lastly to hard drugs. Most importantly, individuals who do not use substances at one stage rarely initiate use of any of the substances associated with later stages. Much subsequent research has confirmed this general sequence (Andrews et al. I991; Blaze-Temple and Lo 1992; Brook et al. 1982; Donovan and Jessor 1983; Elliott et al. 1989; Fleming et al. 1989; Hays and Ellickson 1991; Kandel et al. 1992; Welte and Barnes 1985). Because of their role in early stages of this process leading to hard drug abuse, alcohol, tobacco and marijuana came to be known as gateway drugs.
It is important to identify whether use of alcohol in adolescence somehow causes subsequent hard drug abuse or simply identifies some youths who are at higher risk of becoming hard drug abusers. The more naive political rhetoric has implied the former while the scientific literature has concentrated on the latter. This paper disputes the contention that alcohol use causes hard drug abuse. It concludes by recommending more appropriate prevention policies and by identifying important directions for future research.
Kandel's Original Model
Denise Kandel based her stages theory on findings from her reading of several longitudinal studies of development including her own (Kandel 1978;Yamaguchi and Kandel 1984). Her study followed a representative sample of 1,325 New York State public secondary school students recruited in 1971. The analysis examined the variation in the sequence of initiation for the following categories of substances: 1) alcohol, 2) cigarettes, 3) marijuana, 4) illicit drugs such as cocaine and heroin, and 5) prescribed psychoactive drugs such as tranquilizers or stimulants. Her study considered only those substances an individual reported having used at least 10 times. Various modified Guttman scales were examined by first proposing a series of rules thought to characterize the use of which substances typically preceded others, and then identifying which substance use histories conformed to these rules. The following rules summarize the substance use sequences characterizing the progression of 87% of male respondents:
Typical Sequence of Substances Used by Male Respondents:
Alcohol preceded marijuana
Alcohol and marijuana preceded other illicit drugs
Alcohol, cigarettes, and marijuana preceded prescribed psychoactive drugs
The following rules summarize the substance use sequences characterizing the progression of 86% of female respondents:
Typical Sequence of Substances Used by Female Respondents:
Either alcohol or cigarettes preceded marijuana
Alcohol, cigarettes and marijuana preceded other illicit drugs
Alcohol and either cigarettes or marijuana preceded prescribed psychoactive drugs
Kandel explicitly rejected the set of rules corresponding to the gateway model because it described a smaller proportion (82% for male respondents, and 79% for female respondents). …