Results
First of all, it can be noticed that the reformulation of the OxyContin will affect its misuse.
Indeed, it is shown graphically that in the states with the highest initial OxyContin misuse, the rate of
OxyContin misuse declined, while OxyContin misuse actually increased slightly in states with the
lowest rate of initial OxyContin misuse.
Secondly, it is examined whether the heroine mortality has changed by the decrease in
OxyContin misuse. According to the study conducted and the results, we can see that the reformulation
has a high impact on the heroin overdose. Indeed, the event study coefficients are close to zero and
statistically insignificant before the reformulation. It shows that there were no differences in per capita
heroin-related death trends before the reformulation between states with high initial rates of OxyContin
abuse and those with low rates of misuse.
In fact, the correlation between the OxyContin misuse and the heroin deaths per capita before the
reformulation is only 0,019.
But after the reformulation in 2010, we can observe a statistically net increase in death from
heroin overdose in states with the highest initial rates of OxyContin misuse and in addition to this fact
we also observe that this effect grows larger in 2012 and 2013. These two last statements allow us to
suggest that there is a causal relationship between the OxyContin reformulation and the significant
increase in heroin deaths.
Moreover, we can notice that in the relationship between OxyContin misuse and changes in
heroin death rates that a 1 percentage point higher rate of initial OxyContin misuse leads to an additional
2,2 heroin deaths per 100.000. If we add policy variables as prescription drug monitoring programs or
the presence of a medical marijuana law and pain clinic law, we observe that the estimate is not greatly
affected by these additional controls. Furthermore, when initial pain relievers are added to the equation,
we can see an increase in heroin deaths by 3,6 deaths per 100.000 in 2013, this proves us that the two
variables are correlated. We find the same results for the heroin mortality on the exclusive presence of
heroin at the time of death.
Another table shows us that the largest increase in heroin death occurs for individuals ages 25
to 64, also the effect is greater for men than for woman and the rise in heroin deaths is mostly focused
among whites. It is also statistically found that there is an increase in heroin deaths for the more educated
people. In short, the rise in heroin deaths is concentrated among white middle-aged working men.
The effect of the reformulation on opioid death is also studied. It is shown that opioid deaths
per capita were increasing faster in states with high initial OxyContin misuse. But after the reformulation
in 2010, we observe a leveling off and a small decrease in opioid deaths in states with higher initial
OxyContin misuse.
However, when we estimated the effect of OxyContin misuse and pain reliever misuse together,
we can observe that high OxyContin misuse is related with a statistically insignificant increase in opioid
deaths after reformulation.
Then we consider the effects of the reformulation on natural opioid mortality (excluding heroin,
methadone and synthetic opioids). Following that we can see that the linear estimates are increasing in
magnitude but in result the opioid mortality are noisy. Nonetheless these results are suggestive of a
reduction in natural opioids deaths.
In the same case as the natural opioids, we examine the effects that the reformulation of the
OxyContin might have on the substitution to synthetic opioids. After review, we can estimate that the
effect of reformulation is positive but not statistically significant
Finally, we review the effect of OxyContin reformulation on total drug overdose deaths. First,
as said before, the reformulation increased heroin deaths but it also decreased (mostly insignificant)
natural opioid mortality. But on the other hand, we can observe a growing trend in the coefficients before
the reformulation, the same thing happens for all drug overdose.
It is found that the initial nonmedical use of OxyContin is not statistically significantly
associated to changes in drug overdoses. However, there is too much noise to estimate the exact effects.
Globally, results imply that the rise in death from heroin and fentanyl counterbalance any
decrease in natural opioid deaths, which lead to no net reduction in total overdose from the
reformulation.
In addition, we can consider alternative explanations for the relationship between the rise in
heroin deaths overdose and the reformulation of the OxyContin and its initial misuse. To do so we
included time-varying indicator variable. First of all, the PDMP, including this variable doesn’t vary
that much the effect on the estimate. Secondly, we examine if the state has medical marijuana laws
(MMLs) and find that this also has little effect on the estimate.
Another issue is the case of pill mill laws in Florida. Pill mills are pain clinics that illicitly sell
prescription medication. As Florida’s lax regulation it has allowed a serious rise in opioid supply in the
2000s. If we exclude Florida from the sample, the estimate rises slightly.
It is also said that a reduction in heroin price could explain the increase in heroin overdose, but
it is found that the state-level heroin price changes are not correlated with the initial OxyContin misuse,
so they are implausible to describe the differential increase in heroin death. It is also said that previous
work concluded that opioid deaths rise during time period with high unemployment rates
(Hollingsworth, Ruhm and Simon 2017).
As a conclusion, it can be stated that the reformulation can explain 0,37 heroin deaths per
100.000 in 2011, 0,94 deaths in 2012 and 1,10 deaths in 2013. Between 2010 and 2013 the heroin deaths
rate has doubled and if there hadn’t been the reformulation, we would have observed only a 21%
increase. Therefore, it implies that the reformulation counts for 80% of the recent growth in heroin
deaths