Discussion
In this study, we have examined drug-related deaths in the southern Swedish county of Skåne as the level of access to OST has increased sharply following the introduction of a patient choice reform in 2014, in parallel with a gradual shift towards increased symptom tolerance and a more harm reduction-oriented approach in OST treatment. In summary, OST in Skåne is now conducted more in accordance with a low-threshold paradigm than was previously the case [
16,
19].
One aim of the implementation of the patient choice reform was that deaths due to opioids would decrease in the region as a result of increased access to OST for individuals in need of such treatment [
19,
45]. OST provision has previously been under-dimensioned both in the region and in the rest of the country [
46,
47]. In absolute numbers, there has been an increase in deaths in Skåne due to intoxication with the opioids examined in the study, although analyses of the number of deaths in the region adjusted for population estimates show no significant increase in the mortality rate between the data collection periods. However, the analysis based on national data from the NBHW’s Cause of Death Register for 2011–2017 showed a reduction in unintentional drug intoxications in Skåne after 2014 relative to the rest of the country. The differences in these results can be attributed to the two analyses’ different inclusion criteria for the study populations of interest (with regard to substances and causes of death), different time periods (the forensic material from Skåne includes 2 years that do not run per calendar year), and the fact that the data from the NBHW cover more years. However, taken together, the results from these analyses suggest that there has not been a significant increase in opioid-related deaths in Skåne following the implementation of the patient choice reform. At the same time, support for the expectation that the reform would be associated with a reduction in opioid deaths in Skåne is weak.
The proportion of individuals who at the time of death were registered as resident in municipalities with unchanged access to OST increased between the data collection periods. The expansion in the number of patients receiving OST may have helped to restrain opioid-related mortality in municipalities with improved access to OST, where opioid-dependent individuals are able to initiate OST more easily and may now also remain in treatment regardless of relapses. A previous evaluation has shown proximity to the clinic to be important for patients in OST when choosing a treatment facility [
19]. In recent years, there has been a shift in several western countries towards an increasing number of opioid deaths in less densely populated communities outside metropolitan areas [
48‐
50]. In this study, the three larger municipalities in Skåne were the places in which access to OST had increased the most and no increase in the proportion of deaths was noted in these. Municipalities with unchanged access to OST, on the other hand, are largely comprised of areas with longer geographical distances to an OST clinic. This group mainly consists of a large number of smaller municipalities. It is possible that the results in the present study in a way reflect this shift towards opioid use and deaths being more common in smaller communities. In this context, however, it should be clarified that a shortcoming in the current analysis is the premise that proximity to treatment, i.e. that OST is available in the municipality, is desirable in order to reach the aim of a reduction in opioid-related deaths. At the same time, it is unrealistic for most of the smaller communities in Skåne to have an OST-clinic located in each municipality.
Prior to the introduction of the patient choice reform, a concern was raised that an expansion of the number of patients in treatment, and thus an increase in individuals receiving medication in the form of methadone and buprenorphine, could lead to increased diversion of these medications to people not in OST. This is something that has been observed in other studies where access to OST has increased [
17,
18,
27,
30,
51,
52]. The analyses in this study show that there was no significant increase in deaths caused by methadone or buprenorphine in general in Skåne between periods examined. There has been a change in which opioids cause the most deaths in many western countries since the turn of the millennium, from heroin to prescription opioids, including methadone and buprenorphine [
53‐
56]. This trend has also been noted in Sweden [
8,
40,
57]. In a recently published study Fugelstad and colleagues showed that methadone-related deaths have increased among Swedish 15–29-year olds between 2006 and 2015. Only a few individuals had been prescribed methadone the year before the death, which indicates that the increasing trend was mainly a result of an increased exposure to non-prescribed methadone among younger opioid users [
57]. Another recent study by Mariottini and colleagues [
58] investigated buprenorphine-related deaths in Finland 2016–2019. The results show high concomitant use of primarily benzodiazepines in buprenorphine poisonings and indicate an increase in buprenorphine-related deaths, especially among younger individuals. The study did not examine the proportion among the deceased who had prescriptions of buprenorphine or experience of OST [
58]. The results of these, and other, studies illustrate a current increase in deaths related to OST-medications. In contrast to this, the increased prescription of methadone and buprenorphine linked to the patient choice reform has, in the present study, not been associated with increased regional mortality as a result of intoxication with these substances.
When patients, as in this study, are able to initiate and remain in OST even though they may have a potentially life-threatening use of other narcotic drugs, the fact that a larger proportion of patients in the present study died during ongoing treatment in the second data collection period might be viewed as a natural consequence of this. One possible explanation for this finding, in addition to the large increase in the number of patients in treatment, may be that OST-patients are not being discharged from treatment to the same extent as before the introduction of the patient choice reform, in combination with the changes in national guidelines, as presented in a previous study [
19]. In line with this, a recent study from low-threshold OST programs in Norway found that more than half of the deaths during OST over 2 years were drug-induced [
59]. The authors express concern about the large number of cases where an opioid, including the patient’s prescribed OST medication, was the main intoxicant in overdose deaths. Higher pooled concentrations of opioids were found among the drug-induced deaths compared to those who died from other causes. Among the deceased in overdose who were prescribed buprenorphine, other opioids (mainly heroin) were found to a high extent [
59]. In our study, we have not investigated the concentration of substances at death, nor do we know which opioid caused the deaths in the individuals who were on OST at time of death. Nevertheless, the findings in these studies highlight the aspect of caution related to patients with concomitant use of non-prescribed drugs in more low-threshold OST settings. It should also be noted that the ability of the OST clinics to reach patients with risky opioid use for preventive measures such as naloxone distribution and overdose information may be greater than before, with more patients with lower treatment compliance and an ongoing use of illicit or prohibited drugs remaining in treatment [
17,
34,
60].
Strengths and limitations
Possible strengths of the present study include the fact that the forensic data cover a complete regional population of individuals subject to forensic examination and that the manual searches reduce the risk of missing cases that should be included in the study. The unique personal identification number provides easy linkage between patient registers. The national level data from the NBHW’s Cause of Death Register are of high quality in terms of their level of completeness with regard to the inclusion of the total number of deaths that occur in Sweden annually.
One of the study’s limitations is that we lack data for the prevalence and development of illicit use of opioids and opioid dependence in Skåne and Sweden during the years covered by the study.
The number of opioid-related deaths examined forensically has increased continuously in Sweden in the last two decades. Concern has been raised if this increase to a substantial degree could be attributed to improvements and changes in forensic toxicology [
61]. This has been thoroughly analyzed by Leifman [
8], who concludes that the increase in the presence of drugs in forensically investigated deaths mainly is due to an increase in the actual number of opioid-related deaths, even when taking into consideration factors such as lowered threshold values in forensic toxicology analyses and an increasing screening for drugs. Almost all changes in toxicological analyses and screening took place before 2012, which means that they cannot have affected our regional level data. However, it cannot be ruled out that the changes to a minor extent may have affected the national level data.
Another limitation of the study concerns the fact that both data sets consist of relatively few cases, which diminishes the possibility of drawing general conclusions regarding opioid-related deaths on the basis of the study’s results. Another weakness is the shortness of the time that elapsed between the two data collection periods, and that a gradual change towards a more tolerant attitude towards relapse and the exclusion criteria employed in OST practice had begun prior to and continued during the period in which the empirical data were collected. However, the major impact of the examined intervention, i.e. a sharp increase in the number of treatment places and patients in OST, can be attributed to the implementation of the patient choice reform [
19]. The choice of study design by division into time periods rather than analyzing year by year was made in order to best address the research questions concerning the effects of the introduction of the reform on opioid deaths in the region.
Conclusion
Increased access to and lower treatment thresholds in OST have not led to a reduction in opioid-induced deaths in the short term in Skåne County in southern Sweden. There has been an increase in the actual number of such deaths in the county, but this increase was not significant when adjusted for population size. An analysis of national death data, however, shows a relative decrease in unintentional drug intoxication deaths in Skåne compared to the rest of Sweden following the implementation of the patient choice reform for OST in Skåne. This discrepancy between the results from these different analyses calls for more research to further elucidate this matter.
Deaths due to intoxication with the OST drugs methadone and buprenorphine showed no increase between the data collected prior to and after the introduction of the patient choice reform, indicating that the hypothesis that a higher number of patients in OST might lead to increased mortality due to the diversion of such medications was not supported.
A geographical comparison between individuals who at the time of death were registered as resident in municipalities with increased or unchanged access to OST showed an increase in the proportion of deaths in municipalities with unchanged access to OST.
Following the increase in access to and in the number of patients in OST in Skåne, a larger proportion of patients died during ongoing OST following the introduction of the reform. This can probably be attributed to the greater number of OST clinics and the increase in the number of patients in treatment, and to the policy change which has meant that non-compliance with treatment, in terms of illicit drug use during treatment, no longer necessarily leads to discharge. One implication of the results relating to the increase in deaths among individuals receiving OST at the time of death is the significance of the way in which OST staff work with patients with an ongoing use of illicit or prohibited drugs. OST should therefore be highlighted as an important area for overdose prevention measures aimed at this group of problematic opioid users, such as naloxone distribution and information on safer drug use.
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