Sunday, August 23, 2015

Drugs and harm

FactCheck: is ice more dangerous and addictive than any other illegal drug?

I made a complaint recently that there is a lot of dubious rhetoric floating around when it comes to drug reform advocates talking about comparative risk for drugs.

This article does provide some useful figures, some of which are surprising:
 Fewer people use ice than alcohol, tobacco, cannabis, ecstasy and pharmaceuticals
for non-medical purposes; 2.1% of Australians are methamphetamine users
(1% use ice), while 80% are alcohol users and 10% are cannabis users.
That's fewer meth users than media attention to the problem might suggest, but as the article goes to note, the "ice" phenomena is about the growth of it as the preferred type of methamphetamine, and its increase in frequency of use:
The same data show that about half of methamphetamine users prefer
ice over other forms. The proportion of users who use ice as their main
form of methamphetamine has doubled since 2010 - from 22% of users to
50% of users. This suggests that regular users are switching from speed
to ice.
In addition, these data show that existing users are using more
frequently, with a larger percentage of users reporting using weekly or
daily, but a lower quantity. As a result of these changes, we have seen
an increase in harms associated with methamphetamine use.
The part that surprised me more, however, is the one about the number of ambulance attendances for cannabis use.  Don't hear that bandied about much in drug reform circles:
 In Victoria, there are an average of 4.7 methaphetamine-related ambulance attendances
a day (3.4 of those for ice) and about 87% of those cases are transported to hospital. This is less than alcohol (34 attendances per day), benzodiazepines (8.3 attendances per day) and heroin (5.1attendances per day). And it is similar to cannabis, with 4.4 attendances a day and around 86% transported to hospital.
Perhaps the article doesn't contain enough accurate information to be sure, but if alcohol is used by 80% of people versus 10% cannabis, it would seem the ambulance attendance figures for alcohol compared to cannabis are about the same.    Very interesting...

As for a valid comparison between the "danger" of different drugs, the article goes squishy at the end:
 While we certainly need to address the harms associated with methamphetamine use, we should keep in mind that our most widely used drug – alcohol - still results in more harms to individuals and the community, and other illicit drugs are also associated with more harms.
Of course alcohol causes more harms "to individual in the community" - it's used by 80 times more people.

And the article does link to a 2007 study by former UK drug policy adviser David Nutt. But as another article shows, the exercise Nutt went through with drug experts to rank drugs in terms of their danger is fraught with difficulties:
Nutt's analysis measures two different issues related to drug use in the UK: the risk to an individual, and the damage to society as a whole.

The individual scores account for a host of variables, including mortality, dependence, drug-related family adversities, environmental damage, and effect on crime.

Even if two drugs score similarly in Nutt's analysis, the underlying variables behind the scores can be completely different. For instance, heroin and crack cocaine are fairly close in the rankings. But heroin scores much higher for mortality risk, while crack poses a much bigger risk for mental impairment.

There's also some divergence within the specific categories of harm. Alcohol and heroin both score high for crime. But alcohol's crime risk is due to its tendency to make people more aggressive (and more prone to committing crime), while heroin's crime risk is based on the massive criminal trafficking network behind it.

The analysis doesn't fully account for a drug's legality or accessibility. If heroin and crack were legal and more accessible, they would very likely rank higher than alcohol. The harm score for marijuana would also likely rise after legalization, but probably not too much since pot use is already widespread....
"You can always create some composite, but composites are fraught with problems," Caulkins said. "I think it's more misleading than useful."

The blunt measures of drug harms present similar issues. Alcohol, tobacco, and prescription painkillers are likely deadlier than other drugs because they are legal, so comparing their aggregate effects to illegal drugs is difficult. Some drugs are very harmful to individuals, but they're so rarely used that they may not be a major public health threat. A few drugs are enormously dangerous in the short-term but not the long-term (heroin), or vice versa (tobacco). And looking at deaths or other harms caused by certain drugs doesn't always account for substances, such as prescription medications, that are often mixed with others, making them more deadly or harmful than they would be alone.
Excellent.  Backs up the skepticism I've had about comparative "drugs harms" claims for years.


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