Painkiller overdoses significant lower in states with medical marijuana

[Nanners]

http://archinte.jamanetwork.com/article.aspx?articleid=1898878


Results Three states (California, Oregon, and Washington) had medical cannabis laws effective prior to 1999. Ten states (Alaska, Colorado, Hawaii, Maine, Michigan, Montana, Nevada, New Mexico, Rhode Island, and Vermont) enacted medical cannabis laws between 1999 and 2010. States with medical cannabis laws had a 24.8% lower mean annual opioid overdose mortality rate (95% CI, −37.5% to −9.5%; P = .003) compared with states without medical cannabis laws.

Conclusions and Relevance Medical cannabis laws are associated with significantly lower state-level opioid overdose mortality rates. Further investigation is required to determine how medical cannabis laws may interact with policies aimed at preventing opioid analgesic overdose.

In 2013 opioid painkillers caused 420,000 emergency room visits and 16,235 deaths (http://www.cdc.gov/drugoverdose/data/overdose.html)

[~primetime~]

I have to say, that is pretty awesome.

[~primetime~]

To really understand the effect though I think you need to compare opioid deaths before and after legalization in those states...not compare deaths with the other states.

[Nanners]

To really understand the effect though I think you need to compare deaths before and after legalization in those states...not compare deaths with the other states.

they did




The opioid analgesic overdose mortality rate in each state from 1999 to 2010 was abstracted using the Wide-ranging Online Data for Epidemiologic Research interface to multiple cause-of-death data from the Centers for Disease Control and Prevention.15 We defined opioid analgesic overdose deaths as fatal drug overdoses of any intent (International Statistical Classification of Diseases,10th revision [ICD-10], codes X40-X44, X60-X64, and Y10-Y14) where an opioid analgesic was also coded (T40.2-T40.4). This captures all overdose deaths where an opioid analgesic was involved including those involving polypharmacy or illicit drug use (eg, heroin). Analysis of publicly available secondary data is considered exempt by the University of Pennsylvania Institutional Review Board.

Three states (California, Oregon, and Washington) had medical cannabis laws effective prior to 1999.6 Ten states (Alaska, Colorado, Hawaii, Maine, Michigan, Montana, Nevada, New Mexico, Rhode Island, and Vermont) implemented medical cannabis laws between 1999 and 2010. Nine states (Arizona, Connecticut, Delaware, Illinois, Maryland, Massachusetts, Minnesota, New Hampshire, and New York) had medical cannabis laws effective after 2010, which is beyond the study period. New Jersey’s medical cannabis law went into effect in the last quarter of 2010 and was counted as effective after the study period. In each year, we first plotted the mean age-adjusted opioid analgesic overdose mortality rate in states that had a medical cannabis law vs states that did not.

Next, we determined the association between medical cannabis laws and opioid analgesic–related deaths using linear time-series regression models. For the dependent variable, we used the logarithm of the year- and state-specific age-adjusted opioid analgesic overdose mortality rate. Our main independent variable of interest was the presence of medical cannabis laws, which we modeled in 2 ways.

In our first regression model, we included an indicator for the presence of a medical cannabis law in the state and year. All years prior to a medical cannabis law were coded as 0 and all years after the year of passage were coded as 1. Because laws could be implemented at various points in the year, we coded the law as a fraction for years of implementation (eg, 0.5 for a law that was implemented on July 1). The coefficient on this variable therefore represents the mean difference, expressed as a percentage, in the annual opioid analgesic overdose mortality rate associated with the implementation of medical cannabis laws. To estimate the absolute difference in mortality associated with medical cannabis laws in 2010, we calculated the expected number of opioid analgesic overdose deaths in medical cannabis states had laws not been present and subtracted the actual number of overdose deaths recorded.

In our second model, we allowed the effect of medical cannabis laws to vary depending on the time elapsed since enactment, because states may have experienced delays in patient registration, distribution of identification cards, and establishment of dispensaries, if applicable. Accordingly, we coded years with no law present as 0, but included separate coefficients to measure each year since implementation of the medical cannabis law for states that adopted such laws. States that implemented medical cannabis laws before the study period were coded similarly (eg, in 1999, California was coded as 3 because the law was implemented in 1996). This model provides separate estimates for 1 year after implementation, 2 years after implementation, and so forth.

Each model adjusted for state and year (fixed effects). We also included 4 time-varying state-level factors: (1) the presence of a state-level prescription drug monitoring program (a state-level registry containing information on controlled substances prescribed in a state),16 (2) the presence of a law requiring or allowing a pharmacist to request patient identification before dispensing medications,17 (3) the presence of regulations establishing increased state oversight of pain management clinics,18 and (4) state- and year-specific unemployment rates to adjust for the economic climate.19 Colinearity among independent variables was assessed by examining variance inflation factors; no evidence of colinearity was found. For all models, robust standard errors were calculated using procedures to account for correlation within states over time.

To assess the robustness of our results, we performed several further analyses. First, we excluded intentional opioid analgesic overdose deaths from the age-adjusted overdose mortality rate to focus exclusively on nonsuicide deaths. Second, because heroin and prescription opioid use are interrelated for some individuals,20- 23 we included overdose deaths related to heroin, even if no opioid analgesic was coded. Third, we assessed the robustness of our findings to the inclusion of state-specific linear time trends that can be used to adjust for differential factors that changed linearly over the study period (eg, hard-to-measure attitudes or cultural changes). Fourth, we tested whether trends in opioid analgesic overdose mortality predated the implementation of medical cannabis laws by including indicator variables in a separate regression model for the 2 years before the passage of the law.24 Finally, to test the specificity of any association found between medical cannabis laws and opioid analgesic overdose mortality, we examined the association between state medical cannabis laws and age-adjusted death rates of other medical conditions without strong links to cannabis use: heart disease (ICD-10 codes I00-I09, I11, I13, and I20-I51)25 and septicemia (A40-A41). All analyses were performed using SAS, version 9.3 (SAS Institute Inc).

[shlver]

the confidence interval is still pretty wide so more states legalizing would give more meaningful data but I do think more legalization would yield similar results.

[Dresta]

I wonder if this has to do partly with people taking opiates and cannabis together. The problem is, if you're really in pain, cannabis is not anything like as effective as an opiate, and i mean, it's not even close. So i don't see how this could reduce overdoses in people suffering from serious pain, unless it is due to the effective mixing of the two drugs. Thus it seems likely to me that the fakers and minor pain sufferers (who become drug abusers) are the one's mostly benefitting from this, though i don't know how the two could be effectively delineated.

Cannabis synergises really well with opiates, and i find, that once the opiate starts wearing off, smoking some really halts the desire to keep chasing the high, and to take more opiates (which is what those who od are likely doing, as are they likely mixing it with booze). It is a really depressing feeling when opiates start to wear off (particularly when you are hooked), and that makes some people act recklessly. That might be part of what is happening here, though it is impossible to know for sure.

[~primetime~]

This is evidence that legalization INCREASES use though.

One of the biggest arguing points for those wanting to legalize anything is that legalization doesn't increase use...that users can get it on the black market just as easy, etc.

[Dresta]

Of course easier access is going to lead to increased use, particularly in the short-term.

Maybe it will reduce use among the underage, if it is policed effectively.

[Dresta]

Also, for pain relief there's an opiate-like substance called Kratom that is, i think, nearly impossible to od from. It'd be good if more people knew about this, as it is likely to be banned at some point on the future (already has been in a bunch of states, is going to be in the UK's blanket ban on legal highs and such), and really there's no sensible reason for doing so.

It is an effective and cheap way to treat pain, so it probably won't last.