Using Marijuana May Not Raise the Risk of Using Harder Drugs (but look at alternative explanation)

RAND's Drug Policy Research Center ^ | December 2, 2002 | RAND's Drug Policy Research Center

[unspun]

Using Marijuana May Not Raise the Risk of Using Harder Drugs

Marijuana is widely regarded as a "gateway" drug, that is, one whose use results in an increased likelihood of using more serious drugs such as cocaine and heroin. This gateway effect is one of the principal reasons cited in defense of laws prohibiting the use or possession of marijuana. A recent analysis by RAND's Drug Policy Research Center (DPRC) suggests that data typically used to support a marijuana gateway effect can be explained as well by a different theory. The new research, by Andrew Morral, associate director of RAND Public Safety and Justice, Daniel McCaffrey, and Susan Paddock, has implications for U.S. marijuana policy. However, decisions about relaxing U.S. marijuana laws must necessarily take into account many other factors in addition to whether or not marijuana is a gateway drug.

Support for the Gateway Effect

Although marijuana has never been shown to have a gateway effect, three drug initiation facts support the notion that marijuana use raises the risk of hard-drug use:

• Marijuana users are many times more likely than nonusers to progress to hard-drug use.

• Almost all who have used both marijuana and hard drugs used marijuana first.

• The greater the frequency of marijuana use, the greater the likelihood of using hard drugs later.

This evidence would appear to make a strong case for a gateway effect. However, another explanation has been suggested: Those who use drugs may have an underlying propensity to do so that is not specific to any one drug. There is some support for such a "common-factor" model in studies of genetic, familial, and environmental factors influencing drug use. The presence of a common propensity could explain why people who use one drug are so much more likely to use another than are people who do not use the first drug. It has also been suggested that marijuana use precedes hard-drug use simply because opportunities to use marijuana come earlier in life than opportunities to use hard drugs. The DPRC analysis offers the first quantitative evidence that these observations can, without resort to a gateway effect, explain the strong observed associations between marijuana and hard-drug initiation.

New Support for Other Explanations

The DPRC research team examined the drug use patterns reported by more than 58,000 U.S. residents between the ages of 12 and 25 who participated in the National Household Surveys on Drug Abuse (NHSDA) conducted between 1982 and 1994.^[1] Using a statistical model, the researchers tested whether the observed patterns of drug use initiation might be expected if drug initiation risks were determined exclusively by

• when youths had a first opportunity to use each drug

• individuals' drug use propensity, which was assumed to be normally distributed^[2] in the population

• chance (or random) factors.

To put it another way, the researchers addressed the question: Could the drug initiation facts listed in the first section of this brief be explained without recourse to a marijuana gateway effect?

Figure 1—Probabilities of Initiating Hard Drugs, Marijuana Users and Nonusers

The research team found that these associations could be explained without any gateway effects:

• The statistical model could explain the increased risk of hard-drug initiation experienced by marijuana users. Indeed, the model predicted that marijuana users would be at even greater risk of drug use progression than the actual NHSDA data show (see Figure 1).

• The model predicted that only a fraction of hard-drug users would not have tried marijuana first. Whereas in the NHSDA data 1.6 percent of adolescents tried hard drugs before marijuana, the model predicted an even stronger sequencing of initiation, with just 1.1 percent trying hard drugs first.

• The modeled relationship between marijuana use frequency and hard-drug initiation could closely match the actual relationship (see Figure 2).

The new DPRC research thus demonstrates that the phenomena supporting claims that marijuana is a gateway drug also support the alternative explanation: that it is not marijuana use but individuals' opportunities and unique propensities to use drugs that determine their risk of initiating hard drugs. The research does not disprove the gateway theory; it merely shows that another explanation is plausible.

Figure 2—Probabilities of Hard-Drug Initiation, Given Marijuana Use Frequency in the Preceding Year

Some might argue that as long as the gateway theory remains a possible explanation, policymakers should play it safe and retain current strictures against marijuana use and possession. That attitude might be a sound one if current marijuana policies were free of costs and harms. But prohibition policies are not cost-free, and their harms are significant: The more than 700,000 marijuana arrests per year in the United States burden individuals, families, neighborhoods, and society as a whole.

Marijuana policies should weigh these harms of prohibition against the harms of increased marijuana availability and use, harms that could include adverse effects on the health, development, education, and cognitive functioning of marijuana users. However, the harms of marijuana use can no longer be viewed as necessarily including an expansion of hard-drug use and its associated harms. This shift in perspective ought to change the overall balance between the harms and benefits of different marijuana policies. Whether it is sufficient to change it decisively is something that the new DPRC research cannot aid in resolving.

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^[1]In subsequent years, respondents have not been asked about their first opportunity to use various drugs.

^[2]That is, some people have a high or low propensity, but most people have a propensity near the middle of the range.

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RB-6010 (2002)

RAND research briefs summarize research that has been more fully documented elsewhere. This research brief describes work done in RAND's Drug Policy Research Center, a joint endeavor of RAND Public Safety and Justice and RAND Health. The research is documented in "Reassessing the Marijuana Gateway Effect" by Andrew R. Morral, Daniel F. McCaffrey, and Susan M. Paddock, Addiction 97:1493-1504, 2002.

Abstracts of RAND documents may be viewed at www.rand.org. Publications are distributed to the trade by NBN. RAND^® is a registered trademark. RAND is a nonprofit institution that helps improve policy and decisionmaking through research and analysis; its publications do not necessarily reflect the opinions or policies of its research sponsors.

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RAND Home Page

[Republic of Texas]

I've been clean and sober 12 years now as well. Many who argue for legalization of drugs, have never experienced the addictive power of many of the drugs they proselytize for. I find it funny, in a sad way, that they argue so vociferously, for something they know nothing about.

[MrLeRoy]

I know this:

Drug Category | Proportion of Users That Ever Became Dependent (%)

Tobacco 32

Alcohol 15

Marijuana (including hashish) 9

Anxiolytics (including sedatives and hypnotic drugs) 9

Cocaine 17

Heroin 23

[unspun]

You are such a thorough guy!

[MrLeRoy]

(That's data from the Institute of Medicine, by the way.)

[MrLeRoy]

I've been clean and sober 12 years now as well.

Congratulations. Ever been addicted to alcohol or tobacco?

Many who argue for legalization of drugs, have never experienced the addictive power of many of the drugs they proselytize for. I find it funny, in a sad way, that they argue so vociferously, for something they know nothing about.

There are ways of knowing other than personal experience---and for some purposes those ways are better.

[Atlas Sneezed]

"Exactly. Do you speed?"

If you think that exceeding posted speed limits suggests a tendency toward criminal activity, then you probably have trouble getting the taste of jackboot polish out of your mouth.

Not all laws are inherently good.

[Republic of Texas]

To answer your question, yes and no.

I'm suprised, in the interest of being thourough, you haven't tried heroin or crack yet. Get back to me when you do. I'll be more interested in your opinion at that time.

Reading IS a great way to learn, but not the ONLY or BEST way everytime.

[sinclair]

I GOT STONED & MISSED IT

I was sitting in my basement.
I just rolled myself a taste
Of something green and gold and glorious
To get me through the day.
Then my friend yelled through the transom
"Grab your coat and get your hat son,
There's a nut down on the corner,
Givin' dollar bills away"

But I laid around a bit
Then I had another hit.
Then I rolled myself a bauma.
Then I thought about my mama.
Then I fooled around, played around
jacked around a while and then,

I got stoned and I missed it.
I got stoned and I missed it.
I got stoned and it rolled right by.
I got stoned and I missed it.
I got stoned and I missed it.
I got stoned... oh me... oh my.

It took seven months of urgin'
Just to get that local virgin
With the sweet face
Up to my place
To fool around a bit.
Next day she woke up rosy,
And she snuggled up so cozy.
When she asked me how I liked it,
Lord it hurts me to admit,

I got stoned and I missed it.
I got stoned and I missed it.
I got stoned and it rolled right by.
I got stoned and I missed it.
I got stoned and I missed it.
I got stoned... oh me... oh my.

I'm makin' no excuses
For the many things I uses
Just to sweeten up my relationships
And brighten up my day.
When my earthly race is over
And I'm ready for the clover
And they ask me how my life has been
I guess I'll have to say,

I got stoned and I missed it.
I got stoned and I missed it.
I got stoned and it rolled right by.
I got stoned and I missed it.
I got stoned and I missed it.
I got stoned... oh me... oh my.

SHEL SILVERSTEIN

[MrLeRoy]

To answer your question, yes

Was it easy to quit compared to other addictions you've quit?

I'm suprised, in the interest of being thourough, you haven't tried heroin or crack yet.

I don't have to put my hand in my lawnmower to know what would happen. (Is my support for the legality of lawnmowers now suspect?)

Get back to me when you do. I'll be more interested in your opinion at that time.

Frankly, I'm not interested in whether you're interested in my opinion.

Reading IS a great way to learn, but not the ONLY or BEST way everytime.

I quite agree.

[Karsus]

Then most drivers in DFW are on the virge of becomming hardcore criminals because you can not drive on the major roads in DFW with out breaking the law.

If you go above the speedlimit you are breaking that law.
If you go the speedlimit you are impeading trafic and breaking that law.

What do you suggest, no one drive?

Since you say that breaking the laws is wrong, what about those how live in countries that ban the Bible but have a Bible anyway, are they in danger of becomming hard core criminals?

[dead]

Your post makes perfect sense to me, but you'll never dissuade the big-government woddies from their quest to make the world behave like they want them to.

They're fanatical.

[rb22982]

Comparing Addictive Qualities of Popular Drugs (Higher score indicates more serious effect)
Drug	Dependence	Withdrawal	Tolerance	Reinforcement	Intoxication
Nicotine	6	4	5	3	2
Heroin	5	5	6	5	5
Cocaine	4	3	3	6	4
Alcohol	3	6	4	4	6
Caffeine	2	2	2	1	1
Marijuana	1	1	1	2	3

Withdrawal: Presence and severity of characteristic withdrawal symptoms.

Reinforcement: A measure of the substance's ability, in human and animal tests, to get users to take it again and again, and in preference to other substances.

Tolerance: How much of the substance is needed to satisfy increasing cravings for it, and the level of stable need that is eventually reached.

Dependence: How difficult it is for the user to quit, the relapse rate, the percentage of people who eventually become dependent, the rating users give their own need for the substance and the degree to which the substance will be used in the face of evidence that it causes harm.

Intoxication: Though not usually counted as a measure of addiction in itself, the level of intoxication is associated with addiction and increases the personal and social damage a substance may do.

Source: Jack E. Henningfield, PhD for NIDA, Reported by Philip J. Hilts, New York Times, Aug. 2, 1994 "Is Nicotine Addictive? It Depends on Whose Criteria You Use."

I can get a good idea

[stuartcr]

Especially off the internet and freerepublic...it's all true.

[MrLeRoy]

Especially off the internet and freerepublic...it's all true.

No, it's not all true---but by reading with a critical eye one can sift the wheat from the chaff.

[stuartcr]

Or at least what you agree with.

[MrLeRoy]

Or at least what you agree with.

It's possible for one to ignore readings one disagrees with---on the Internet or on paper---just as it's possible to ignore experiential lessons one disagrees with. What's your point?

[stuartcr]

Don't have one, I was just bored. You can't always believe what you read, but it's easier to believe, if it's what you want to hear.

[headsonpikes]

"We don't need to be at war on this..."

Oh, yes, we do...but a war of words and ideas, I hope.

IMO, communities of people have always expected their members to adhere to certain behaviors, and to avoid others. Adherence to these various communal mores are not objectionable to me, at all. If the good folks of Hooterville despise the consumption of red meat, for instance, then Hooterville can decline to issue business licenses to butchers; if I think that's stupid, I can leave town.

In my view, the extension of this practice to the nation-state has been a grave error. Few nation-states are compact and uniform enough to legitimize such particularism in human behaviors.

Utopian perfectionism is a hideous distortion of the proper relationship between the citizen and the state. The history of the 20th Century is largely a history of nations gone berserk while possessed of this insane notion. Russia, Germany, China...these and others succumbed to a fearful psychopathy which was rationalized as the 'true' expression of national consciousness.

In America, Prohibition, the eugenics movement, the various insane economic nostrums of '30s-era radicals, and lately, the WOD, are manifestations of this psychopathy. Often, these movements are rooted in a crazed pseudo-scientific delusion of a 'true' understanding of social and political life.

That Americans have permitted their governments to 'establish' certain views to the exclusion of others is a tragedy, whose fruits can be seen in the hideous monopoly in public education by 'progressives', as well as in the hysterical WOD.

These trends represent American Socialism, as distinguished from German Socialism, Russian Communism, Chinese Communism, Italian Fascism, and all the other 'national socialisms' of our bloodstained planet.

Socialism is not merely an economic idea; it is the idea that human beings should be viewed as mere instances of a type instead of as unique individuals. Identity politics is the most obvious manifestation of this delusion in American public life, but it is implicit in all of the intrusive legislation of the past century.

Given current public discourse,I would describe myself as a libertarian Conservative, but would rather be seen as a 'disestablishmentarian'. That term was used to describe those who wished to 'disestablish' the Church of England three centuries ago, but I seek to 'disestablish' educational bureaucracies, health bureaucracies, and the very notion that citizens are 'human resources' to be nurtured and protected by high-minded civil servants.

We must plunge a stake through the heart of Socialism to ensure our survival as free people.

Of course, some folks value group solidarity above individual autonomy, but I cannot see how this can be justified by reference to the 'general welfare' mentioned in the Constitution.

Socialists, of course, have no such compunction.

[Mudboy Slim]

"They're fanatical!!"

So am I...but I'm RIGHT!!

ALL Federal Income Taxes Shall Be VOLUNTARY!!

SITYS...MUD

[TigersEye]

Excellent exposition! My hearty congratulations for your well spoken thoughts!!!