Estimating the number of problem opioid users in Poland

Alkoholizm i Narkomania 2012, Tom 25, nr 4, E1 E8 2012, Instytut Psychiatrii i Neurologii ORIGINAL ARTICLE Estimating the number of problem opioid users in Poland Janusz Sierosławski Institute of Psychiatry and Neurology, Department of Studies on Alcoholism and Drug Dependence Polish version of this article Oszacowanie liczby problemowych użytkowników opioidów w Polsce was published in the quarterly Alkoholizm i Narkomania, 2012, 25, 4, 347 356. Abstract Introduction. The aim of the study was to estimate the number of problem opioid users in Poland. Methods. The estimation was performed using the benchmark method on the basis of treatment data and data on problem opioid users collected in a population survey. Results. The number of problem opioid users in Poland in 2009 is estimated at between 10,400 19,800 persons. This estimation is lower than that for 2005, applying the same method. More than half the problem opioid users reside in three regions: Mazowieckie, Śląskie and Dolnośląskie. Conclusions. A comparison of the number of patients in substitution treatment with the estimated number of problem opioid users leads to the conclusion that the needs of substitution treatment are not satisfied, therefore the scaling-up of substitution treatment programmes ought to remain on the agenda. Key words: problem opioid use, estimation, substitution treatment INTRODUCTION The purpose of estimating the number of problem opiate users is to provide a basis for the assessment of dependency treatment requirements, including the substitution treatment addressed to that specific dependency group. This type of treatment remains behind requirements in Poland, its availability is highly unsatisfactory and, suffice it to say, we are way behind most of the rest of Europe in this area (1). An estimation of requirements here may therefore act to stimulate the development of substitution treatment availability. By problem opioid user, we mean a person who regularly uses substances from the opioid group (mainly heroin), experiencing serious problems as a result (2). One might say that this definition basically goes along with that of a person dependent on opioids if strictly medical criteria are not applied in the process of definition. Source of financing: statutory funding of the Institute of Psychiatry and Neurology and the National Bureau for Drug Prevention funding Translated into English by Emil Tchorek E1

Janusz Sierosławski Many local estimations have been conducted in Poland (3 8), with the first on a national scale carried out in 1994 (9). The number of problem opioid users for 1993 was estimated using the capture-recapture method in two regions: Wrocław and Kielce. The results for the two regions were extrapolated to the level of the whole country with estimation indicators defined using residential treatment as well as police data as a basis. The residential treatment data indicator was 4.6; that is, the estimated number was 4.6 times larger than the number of patients, and for the police data it was 2.4. Using these indicators, the estimated number of problem opioid users on a national scale came out as between 20 and 40 thousand people (9, 10). It ought to be mentioned that, at the time, opioid users (mainly Polish heroin ) made up the vast majority of all problem drug users (9, 10). Therefore, one can accept that the number of problem opioid users did not much differ from that of the problem drug users. Further estimates of the number of problem drug users were carried out for 2001 with the benchmark method (5). Residential and outpatient treatment data as well as that from a general population survey on problem drug users known to respondents were used. The results of this estimate indicated that the number of problem opioid users in 2001 was between 14 and 28 thousand (5). Research on the general population was repeated and data was once again gathered on problem drug users known to respondents. Here the estimates for 2005 were between 25 and 29 thousand (5). Estimates for 2005 and 2001 did not, therefore, differ a great deal as far as their upper limit was concerned. Also, it ought to be mentioned that the research for 2005 was conducted in exactly the same way as in 2001, with particular care taken to ensure comparability of results. The object of this article is the estimated number of problem opioid users for 2009 on the basis of 2010 survey data and relevant statistics. METHOD The number of problem opioid users in Poland in 2009 was estimated with the benchmark method (11), which belongs to a wider group of multiplayer method tools (12) that define the proportion of subjects featuring a characteristic on which data is being gathered (e.g. undertaking treatment, HIV infection) through the survey. This proportion serves to calculate the multiplier after multiplication by the statistically derived number, giving the estimated quantity. The estimate employed data that were gathered in a population survey conducted by the National Bureau for Drug Prevention in 2010 on a thousand-person random sample of Polish residents between the age of 15 and 64. The surveyors employed a face-to-face interview approach, with General Projekt Sp. z o.o. conducting the field data collection. Special forms were used to gather data on problem drug users personally known to respondents. In particular, information was gained on the undertaking of residential or outpatient treatment in 2009 using the nomination method (11, 12, 13). Data was gathered not on the actual respondents but on the problem drug users they knew, thus E2

Estimating the number of problem opioid users in Poland gathering more information than if the personal experience of respondents was the object of the questions. Moreover, the probability of coming across problem opioid users in a general population survey, even one that is very large, is too low. Information on the undertaking of residential or outpatient treatment by people indicated by the respondents was gathered on special nomination forms that recorded also the gender, age, and type of drug used. The estimate benchmarks derived from medical statistics were the number of resi dential and outpatient patients treated in 2009 for abuse or dependency on opioids (14). As far as the use of medical statistics as a reference point is concerned, the biggest difficulty is identifying the opiate users. Medical statistics in our country do not contain data on drug use patterns, with only International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnosis information available. According to this classification, opioid users appear in category F11 (opioids) and F19 (other and mixed). While the first category does not raise doubts, the second does not allow for the identification of opioid users. In the 2001 and 2005 estimations, it was assumed, on the basis of local studies, that the share of opioid users among residential patients was around 60%, and 50% among outpatient patients. Now, thanks to data from a pilot programme that reported registration for treatment conducted by the National Bureau for Drug Prevention in accordance with European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) methodology (15), a better basis to this estimate has been gained. The proportion of opioid users among F19 diagnosis patients was defined thanks to these data because their range does indeed include information on drug use patterns as well as diagnosis data. Therefore, analysis of this data allows the estimation of the percentage of opioid users in the F19 diagnosis category, which in 2009 was 22% and 32% for residential and outpatient patients respectively. The estimation of the number of opioid users for each of both types of treatment was gained by summing the number of F11 diagnosis category patients and the estimated number of opioid users in the F19 diagnosis category. Analysis of the territorial distribution of the estimation was conducted by region (województwo the largest Polish regional administrative unit) on the basis of territorial allocation of patient numbers for separately residential and outpatient treatment. Data was aggregated by patient place of residence, not treatment, in the case of for residential treatment statistical data while, because of its local character, it was assumed that the region of treatment is the same as that of residence for outpatient treatment statistical data. RESULTS In table 1 we present the figures for all registered patients in the medical statistics, patient numbers from F11 and F19 diagnosis category according to the same source, with the percentage of opioid users diagnosed as F19 estimated on the basis of data from a pilot registration-for-treatment data-gathering programme of as well as the E3

Janusz Sierosławski Table 1. Estimation of problem opioid users in treatment in 2009 Total number of patients (ICD-10: F11-F16, F18, F19) Number of patients with diagnosis F11 Number of patients with diagnosis F19 Percentage of opioid users among patients with diagnosis F19 Total number of opioid users in treatment Residential treatment 15,412 2353 9985 21.6% 4510 Outpatient treatment* 29,889 4380 13,294 32.3% 8674 Source: Own calculations * Data were applied from table 1.35. Number of patients with mental disorders caused by psychoactive substance use in 2009. Diagnosis, gender and age (14). estimated number of opioid problem patients being treated in Poland. The data serving to calculate the proportion of opioid users among F19 diagnosis patients came from 13 outpatient (328 people) and 16 residential (454 people) clinics, and were gathered in 2009. The estimate effectively defined the number of residential treatment opioid users at 4510 and outpatient at 8674. These figures were accepted as a reference point for estimations of the number of problem opioid users in the country as a whole. In the general population survey, 215 respondents out of 5782 knew at least one problem opioid user and so could provide essential information. From the 299 nominations gathered at this source, the estimated residential treatment percentage was 43.2%, with outpatient patients at 43.8% (table 2). Table 2. Estimation of problem opioid users in Poland in 2009 Statistical data (IPiN) Percentage of patients in the survey sample Estimate coefficient Estimates Residential treatment 4510 43.2 2.32 10,444 Outpatient treatment 8674 43.8 2.28 19,794 Since 43.2% of opioid users undertake residential treatment, it is possible to calculate that there are all opioid users together 2.32 times more than those in residential treatment. When we apply the ratio of opioid users in treatment and all affected by the problem to the statistical data of residential treatment for 2009 (4510 people), we gain an estimate of 10,444 people. The analogical multiplier for outpatient treatment data was 2.28, and applied to data from clinics in 2009, it yielded estimates of 19,794 people. It is therefore possible to assume that the number of problem opiate users lies in the range between 10,444 and 19,794, with the middle of the range at 15,119. Data on the territorial distribution of problem opiate use is presented in table 3, with concentrations in three regions, above all in Mazowieckie (4760), then Dolno- E4

Estimating the number of problem opioid users in Poland Table 3. Regional distribution of estimates of problem opioid users in Poland in 2009 Region Estimates on the basis Estimates on the basis of residential treatment of outpatient treatment benchmark benchmark Range midpoint Number Rate per 100,000 population Mazowieckie 3344 6175 4760 91.1 Dolnośląskie 1054 2721 1888 65.6 Lubuskie 672 596 634 62.8 Zachodniopomorskie 427 1092 760 44.9 Pomorskie 441 1252 847 38.0 Łódzkie 736 872 804 31.6 Kujawsko-pomorskie 281 989 635 30.7 Warmińsko-mazurskie 380 491 436 30.6 Podlaskie 363 330 347 29.2 Śląskie 615 1746 1181 25.4 Lubelskie 254 818 536 24.8 Wielkopolskie 693 785 739 21.7 Małopolskie 256 1080 668 20.3 Opolskie 132 204 168 16.3 Świętokrzyskie 115 254 185 14.6 Podkarpackie 118 389 254 12.1 Missing data 282 śląskie (1888) and Śląskie (1181). The lowest numbers are in Opolskie (168), Świętokrzyskie (185) and Podkarpackie (254). Figures perfectly useful for the assessment of therapeutic requirements do not give a good reading of the extent of the threat as they depend on population size. Rates per 100,000 population that eliminate this discrepancy indicate Mazowieckie (91.1), Dolnośląskie (65.6) and Lubuskie (62.8) as the most threatened. DISCUSSION The estimate presented here is subject to reservation and attention should be paid to its limitations. Above all it is necessary to strongly underline that estimates never provide a precise and certain figure for the actual amount of problem drug users. Drug use, especially in a problem manner, belongs to a socially unacceptable category of behaviours on the fringes of the law, hence our having to deal with a hidden population. Therefore, any attempt to define its extent must have an indirect character. Among the various methods applied to this end, the benchmark method does not stand out all that badly in terms of thoroughness and precision (13, 16, 17). Its advantages include its simplicity and low cost of data collection, which may be gained, for example, in the course of general population survey. The quality of the estimate, to a great extent, depends on the quality of data used for this purpose. Residential treatment data do not raise any serious doubts as E5

Janusz Sierosławski a reference point in terms of comprehensiveness. Also, the system of collecting and processing data eliminates the problem of double counting of people if they register for treatment more than once a year. Outpatient treatment data are prone to the double counting error in the case of a patient using more than one outpatient clinic per year. Furthermore, not all clinics offering outpatient treatment are covered by the statistics system, hence the completeness of the data leaves a lot to be desired. It is however worth noting that each of these limitations have opposing influences on the estimation results, so may at least be partly tolerated. The making of reliable estimations of the extent of problem opioid use faces obstacles as far as data availability is concerned. While in survey information on opioid use is gained through users being indicated by respondents, data of this kind is not available in medical statistics, which are treated as a benchmark to conduct estimations. Medical statistics include information only on medical diagnosis, which does not give a basis for unambiguous identification of opioid users, hence the necessity of further estimation, and this increases the margin for possible error. As many authors have pointed out, estimates of problem drug user numbers ought to be treated with great caution, and be seen more as an identification of the scale of the problem, and less as a reading of concrete numerical values (18). The 2009 estimate of 10,400 19,800 problem opioid users is less than the 25,000 29,000 estimate of 2005, suggesting a fall in the number of problem opioid users in the last four years, with a similar tendency observed in the majority of European countries (19). Despite the noted falling tendency, it ought to be stressed that the number of problem users of these substances is still significant, with over half of the population remaining outside any kind of treatment. The results of the estimation convince us that the level of treatment requirement satisfaction, especially for substitution treatment, is far from optimal. In 2009, substitution treatment availability in Poland amounted to 22 programmes, five of which were conducted at penitentiary units; 1945 people received treatment within these programmes in 2009 (20) which means that only around 13% (10 19%) of problem opioid users benefitted from substitution treatment. European Union countries that provide estimates of problem opioid users have an analogical average of 50% (1, 21). In Germany, at the head of the ranking, probably more than 80% of problem opioid users received substitution treatment. Despite the declining tendency in the incidence of problem opioid use, there still remains a need to increase both the number of substitution treatment programmes and the number of places in these programmes. Opioid substitution treatment is recommended by the World Health Organisation and other specialised UN agencies like UNAIDS, UNODC, as well as European Commission agencies, as a method the effectiveness of which is well documented (22). The priority position substitution treatment enjoys in international organisation policy, as it does in the majority of developed countries, was established during the HIV epidemic, which in many countries of our region appeared earliest among injecting opioid users. Experience gained internationally over the last decades confirms E6

Estimating the number of problem opioid users in Poland the effectiveness of this method, especially as far as limiting the risk of infection and death from HIV and HCV (23, 24, 25) is concerned. Conclusion and recommendation. The number of problem opioid users in Poland, according to 2009 estimates, is in the range of 10,400 and 19,800. The number of patients receiving substitution treatment is 2000, indicating a lack of requirement satisfaction in this area. Further development of the substitution treatment availability therefore seems to be necessary. The 2009 estimation does not stand out as especially accurate. Further work on estimation with the aim of increasing result accuracy and reliability is therefore recommended. A promising direction of development is working out a dynamic model that takes into account changes in the size of the researched population (26). REFERENCES 1. EMCDDA (2010) Annual Report 2010. The state of the drug problem in Europe. Lisbon: European Monitoring Centre for Drugs and Drug Addiction. (http://www.emcdda.europa.eu/) 2. Okruhlica L, Sierosławski J (2006) Definitions of dependency and recreational, regular, problematic, harmful drug use. In: Young People and Drugs. Care and Treatment. Strasbourg: Council of Europe Pompidou Group, 15 35. 3. Sierosławski J (2000) Problem drug use in Poznań, Poland: a qualitative approach to needs assessment. In: Fountain J (ed.) Understanding and responding to drug use: the role of qualitative research. Lisbon: EMCDDA, 243 248. 4. Sierosławski J (2006) Problem narkotyków i narkomanii w Warszawie część I [Drugs and drug abuse problems in Warsaw. Part one]. Remedium, 12 (166), 26 27. 5. Sierosławski J (2007) Oszacowanie liczby problemowych użytkowników narkotyków i analiza wzorów używania narkotyków oraz związanych z tym problemów [Estimating the numbers of problem drug users and analysis of patterns of use and related problems]. Warszawa: Instytut Psychiatrii i Neurologii. (http://www.kbpn.gov.pl) 6. Moskalewicz J, Bujalski M, Sierosławski J (2006) Dostępność programów substytucyjnych w Warszawie [The availability of substitution programmes in Warsaw]. Warszawa: Instytut Psychiatrii i Neurologii. (Raport opracowany na zleceniu Urzędu Miasta st. Warszawy) 7. Bujalski M (2006) Lecznictwo substytucyjne w Warszawie. Wybrane działania Samorządu Warszawskiego w zakresie przeciwdziałania narkomanii oraz HV/AIDS wśród dzieci i młodzieży [Substitution treatment in Warsaw: selected activity of the Warsaw City Council in the area of drug abuse and HIV/AIDS prevention among children and young people]. Remedium, special edition, 22 23. 8. Sierosławski J (2010) Oszacowanie popytu na leczenie substytucyjne buprenorfiną w Warszawie [Estimating demand for buprenorfina substitution therapy in Warsaw]. Serwis Informacyjny Narkomania [Drug-Addiction Information Service], 1 (49), 28 36. 9. Moskalewicz J, Sierosławski J (1995) Zastosowanie nowych metod szacowania rozpowszechnienia narkomanii [Application of new methods of estimating the prevalence of drug addiction]. Alkoholizm i Narkomania, 4 (21), 91 102. 10. Sierosławski J, Zieliński A (1997) Comparison of Different Estimation Methods in Poland. In: Stimson GW, Hickman M, Quirk A, Fischer M, Taylor C (eds) Estimating the Prevalence of Problem Drug Use in Europe. Lisbon: EMCDDA, 231 240. 11. Taylor C (1997) Estimating the prevalence of drug use using nomination techniques: an overview. In: Stimson GW, Hickman M, Quirk A, Fischer M, Taylor C (eds) Estimating the Prevalence of Problem Drug Use in Europe. Lisbon: EMCDDA, 157 170. E7

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