While Illicit drugs have long been linked to higher mortality rates, the data is wildly variable.
In a paper recently published in the journal Drug and Alcohol Dependence, Danish researchers attempted to establish standard mortality ratios for the drugs cannabis, cocaine, amphetamine, MDMA (ecstasy) and opioids (e.g. heroin)*, while taking into consideration the effects of two intervening variables: drug injection with needles and psychiatric disorders (Is the mortality rate of cocaine users mediated by whether they have, for example, clinical depression?)
(*Individuals’ primary drug of choice)
The population they looked at included 20,581 people treated for drug abuse in Denmark over a 10-year period from 1996-2006. (These data are correlational and, therefore, the possibility of unidentified moderating variables exerting an effect on death rates is high.)
In brief, the results showed the following:
1. Those who injected drugs showed significantly higher mortality rates across the board. (This does conflict with past findings, which found no difference.)
2. Overall, psychiatric illness was not associated with higher mortality rates, with the exception of cocaine/amphetamine users, who, if they presented with psychiatric disorders, did show higher morality rates.
3. Pot smokers showed 5x increase in mortality rates (compared to the general population). Researchers suggest that increased mortality among pot smokers could be related to driving accidents, violent injuries and various other types of accidents. (a personal note: Based on my personal experience, this seems unlikely. Pot smokers tend to drive very conservatively (too slow, if anything!) and are famously not prone to violence.) What seems more likely to explain pot smokers’ higher mortality rate is that they are also using other drugs. Other studies have borne this out.
4. Cocaine and amphetamine users showed 6x death rates of the general population. Previous reports on stimulant abuse related deaths are highly variable. The variability is likely the result of other factors including physical conditions, HIV/AIDS, overdose, cardiovascular problems, injuries accidents, violent deaths and suicides.
5. Opiod users show increased mortality rates. Findings for both stimulants and opioids are in accordance with studies from other countries. Users of Heroin and other opioids showed by far the highest mortality rates of all drugs of abuse.
6. Ecstasy (MDMA) users did not show increased mortality rates. (However, it’s possible that a low number of deaths from MDMA contribute to low statistical power).
Conclusions that can be drawn from this report? Stay away from all drugs if you want to increase your chances of staying alive; but, especially, don’t do intravenous heroin. Psychiatric disorders plus drugs of abuse aren’t associated with increased mortality risks except for in the case of cocaine/amphetamine. Ecstasy is unlikely to kill you on its own, but that’s not to say it won’t do some long-term damage if abused. Although marijuana users showed higher mortality rates, there’s not good reason to believe this is solely the effect of marijuana, but other factors. Finally, the population under study here consisted of people seeking treatment, so it’s unknown if this represents the drug using population as a whole.
I think it’s pretty clear, given the number of questions and unknowns this study presents, that there is a lot more to learn about drug-related mortality risk.
References
Arendt M, Munk-Jørgensen P, Sher L, & Jensen SO (2011). Mortality among individuals with cannabis, cocaine, amphetamine, MDMA, and opioid use disorders: a nationwide follow-up study of Danish substance users in treatment. Drug and alcohol dependence, 114 (2-3), 134-9 PMID: 20971585
Neuropoly 
“Conclusions that can be drawn from this report?”
Not a lot. I’ve never used any of the drugs in this list, and my social circles have always been largely with people who don’t use them either. But I’ll take a guess that those moderating variables that aren’t account for do account for a lot of the higher death rate.
Socially conservative people tend not to use drugs, tend not to drink and drive, tend not to hang around in bars where young men like to drink and fight, tend not to drive motorcycles, tend to see the doctor when required and then do what the doctor advises; in short, they tend to avoid risky behavior.
I imagine people who inject drugs tend to neglect their health in any number of ways and pay the consequences.
Jim –
“I imagine people who inject drugs tend to neglect their health in any number of ways and pay the consequences.”
That’s basically the conclusion that I would draw from this paper. I still think it’s worthwhile to figure out what those variables might be. Not that they were very well illuminated here.
As to your other point, I’m not willing to concede to your theory that socially conservative people are somehow immune from or less likely to abuse drugs/alcohol. I could throw out individual examples (and boy is it tempting!), but anecdotal evidence is generally not very reliable, so I’ll refrain. Suffice to say that you and your social circle don’t constitute a random sample of social conservatives so I’d be careful to draw grand conclusions based on these observations alone.
“3. Pot smokers showed 5x increase in mortality rates (compared to the general population). Researchers suggest that increased mortality among pot smokers could be related to driving accidents, violent injuries and various other types of accidents. (a personal note: Based on my personal experience, this seems unlikely. Pot smokers tend to drive very conservatively (too slow, if anything!) and are famously not prone to violence.) What seems more likely to explain pot smokers’ higher mortality rate is that they are also using other drugs. Other studies have borne this out.”
I think there is much truth in that statement. I don’t smoke pot myself, but have to say that I did spend many years in Canada and marijuana is decriminalized and greatly smoked in Quebec and BC, and widely accepted, unlike the restrictions in the U.S. Many many people I knew who worked in film, cirque-de-soleil, design offices and just about everywhere smoked pot – and as you know both crime rates and violence is very low in those Canadian provinces. the people who smoked were pretty peaceful. I knew a man who was 93 and said he had smoked pot quite a bit. Even scientist Carl Sagan had wished they would ease pot laws in the state because it helps cancer patients so much.
So I’m no scientist, but must confess that you’re right – that mortality rates among those smoking pot might be more only because of other drugs, but not due to pot alone.
Hello,
First off nice blog very interesting I found it from my log files on my site seems we have a ping back or something that connected us…
What is interesting is a study that I saw while researching my medical marijuana blogs. It states that in the beginning of the research with medical marijuana and HIV/Aids research that it was realized medical marijuana would alleviate the symptoms but it was first thought the use of marijuana would decrease the life of the HIV/Aids patients, though by the end of the research they came to the conclusion that the patients that used medical marijuana actually lived longer before actually expiring.
This being said it is interesting to see these conflicting studies. I would guess that the conclusion on this article is the use of the other drugs. Again and as well I am not a physician or scientist, but if the study was done with just users of marijuana it would be much more telling. As well were some of the chronic pot smokers chronically ill ? Many of the studies of marijuana smokers revolve around around chronic patients, and it almost seems that these were included at that rate. I have had friends that have done all kinds of drugs, the opiate users seem to be spot on , the ecstasy users seem to be on the mark as well the cocaine and amphetamine users. It is just interesting that the mortality rate is that high for marijuana users though you did not if the marijuana users were also drinkers. This could also heavily influence the ratios.
Soo basically you are just making up excuses for marijuana based on personal anecdote and not doing so for other drugs? Why? Driving “conservatively” does not mean safe…nor does it necessarily ensure “normal” reaction time to changing or increasing attentional ndemands. If you are going to blame “other drugs” that are on board, by what logic are those ones not excused on the basis of the marijuana?
Drug Monkey – I’m not “making up excuses,” but rather addressing some speculative thinking on the part of the researchers with speculation of my own, which, yes, is based on personal experience, my own and that of others, news accounts, and anecdotal evidence. This is a blog, not a science journal, so I’m allowed to do that! (although, that didn’t prevent the authors of this study from doing just that- speculating, I mean – in this paper).
The evidence as to the relationship between marijuana impairment and driving fatalities is pretty unclear/scant, as is the correlation between marijuana use and violent injuries. I don’t know about the other drugs and wasn’t inspired to comment on them; the speculation contained in the paper regarding the others perhaps seemed more plausible to me.
If you’re one and the same person who blogs on scienceblogs, where you’ve identified yourself as a scientist who studies drugs of abuse, then I can understand your sensitivity to my speaking off the cuff. If you can point me to some good data showing either driving accidents or violent injuries mediating the relationship between marijuana impairment and fatality rates, please do so, because a cursory search on my end didn’t yield much that looked very solid.
Ahh, yes but that is the rub. Data are scant and messy. Accidents relatively scarce in context of all driving under the influence. THC lasts longer in the body so mere presence may not tell the story- need estimates of decency and dose.
However, the reflexive argument of the cannabis fan about “adjusting” isn’t well supported where it comes to dangerous driving.
I don’t know many people over the age of 55 who smoke marjuana. But I know a lot who have died before or around that age.
Many say that it speeds up the heart rate but lowers the blood pressure. Statistically most men are at their highest risk of heart attack between the ages of 50 and 55, women between 55 and 60. So if you smoke marjuana and make it past 55 you are supposed to be a rare exception. You just have to do a simple search on that.
I don’t thInk it’s too dangerous to smoke it in the younger years of our lives, but based on my own research and observations, later in life, moderate to heavy use it seems to be so.
Also, every heavy to moderate smoker I know seems to lose ambition, passion, interest, they just get up and work and come home they seem to not care about their lives anymore, it’s almost like they all seem so lost or depressed. They just eat, sleep, shit and smoke marjuana. It seems to have more of a psychological effect on people’s lives than a real health effect, except between the above ages stated. And this is the only reason I can come up with why governments would make it illegal. So maybe it is actually addictive, so much so that we zombie our lives not realizing we could have so much more potential.
Light smokers that I know, ones who smoke one to two joints a week seem to be ok and, still have ambition, passion etc as per the above at least. I smoke one two two joints per week too. So times none it just depends.