[Use of the health insurance database by the centres for evaluation and information on pharmacodependance: examples, interests and future prospects]

Early Detection of Prescription Drug Abuse Using Doctor Shopping Monitoring From Claims Databases: Illustration From the Experience of the French Addictovigilance Network

Opioid analgesics and maintenance treatments, benzodiazepines and z-drugs, and other sedatives and stimulants are increasingly being abused to induce psychoactive effects or alter the effects of other drugs, eventually leading to dependence. Awareness of prescription drug abuse has been increasing in the last two decades, and organizations such as the International Narcotics Control Board has predicted that, worldwide, prescription drug abuse may exceed the use of illicit drugs. Assessment of prescription drug abuse tackles an issue that is hidden by nature, which therefore requires a specific monitoring. The current best practice is to use multiple detection systems to assess prescription drug abuse by various populations in a timely, sensitive, and specific manner. In the early 2000's, we designed a method to detect and quantify doctor shopping for prescription drugs from the French National Health Data System, which is one of the world's largest claims database, and a first-class data source for pharmacoepidemiological studies. Doctor shopping is a well-known behavior that involves overlapping prescriptions from multiple prescribers for the same drug, to obtain higher doses than those prescribed by each prescriber on an individual basis. In addition, doctor shopping may play an important role in supplying the black market. The paper aims to review how doctor shopping monitoring can improve the early detection of prescription drug abuse within a multidimensional monitoring. The paper provides an in-depth overview of two decades of development and validation of the method as a complementary component of the multidimensional monitoring conducted by the French Addictovigilance Network. The process accounted for the relevant determinants of prescription drug abuse, such as pharmacological data (e.g., formulations and doses), chronological and geographical data (e.g., impact of measures and comparison between regions), and epidemiological and outcome data (e.g., profiles of patients and trajectories of care) for several pharmacological classes (e.g., opioids, benzodiazepines, antidepressants, and methylphenidate).

[Safety signal detection by the French Addictovigilance Network: Innovative methods of investigation, examples and usefulness for public health]

The French Addictovigilance Network aims to monitor all psychoactive substances with abuse potential including prescription drugs and other legal and illegal substances such as new psychoactive substances (NPS) and its consequences in humans. Created in 1990 through a network of regional addictovigilance centres covering the entire country, these pharmacologists with expertise in addictovigilance have developed interface with different partners (physicians, toxicologists, network of community pharmacies, addictology care centers…) and implemented several original tools of pharmacosurveillance (such as DRAMES [death related to the abuse of medicines] in strong collaboration with toxicologists or such OPPIDUM [observation of illegal products and misuse of psychotropic medications]), complementary to the spontaneous reporting. A such multidimensional approach including proactive surveillance by these tools and also among several heterogenous data sources (such as data from hospitals or claims database) is able to detect early addictovigilance signals and warnings as illustrated with three following examples: cannabis use and acute serious cardiovascular disorders, new synthetic opioids (ocfentanil, carfentanil) and severe opiate overdose or deaths, the diverted use of psychoactive drugs (codeine analgesics or sedative H1 antihistamines called purple drank) by adolescents and young adults. The choice of a broad strategy and the multifaceted system implemented by the French Addictovigilance Network using elements of pharmacology (fundamental, clinical, pharmacoepidemiology) expertise is an innovative method to detect early addictovigilance signals, and to describe its characteristics in order to increase awareness of psychoactive substances by patients, users and health professionals.

Drug abuse monitoring: which pharmacoepidemiological resources at the European level?

Monitoring the potential for abuse and dependence of psychoactive substances falls within the scope of international conventions on narcotic drugs. At the European level, this monitoring is based on activities controlled by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) for substance abuse in general and by the European Medicines Agency (EMA) for marketed drugs, in the context of pharmacovigilance. If France has set up in the early 1990s an original system to assess potential for abuse of psychoactive substances, with specific tools combining both the evaluation of the use of these substances (illicit substances or diverted drugs), and the consequences of that use in terms of morbidity and mortality, there is no equivalent in other European countries. Indeed, unlike the USA, who, for several decades, organized this type of surveillance, with a multisource approach (sentinel systems, databases, medical and administrative data, databases for seeking care in relation abuse), we have not found in other European countries integrated system for identifying a signal of drug abuse, or to assess the impact of measures for minimizing the risk of abuse. However, some recent examples show a growing concern about drug addiction, based on a pharmacoepidemiological approach using pharmacovigilance databases or medical administrative data. These examples illustrate the interest of these approaches in the field of drug of abuse.

[Post-marketing surveillance systems for psychoactive prescription drug abuse]

Drugs affecting the central nervous system form a unique group of products for surveillance because they could be misused, abused or diverted. Considering the characteristics of this behaviour that is often concealed, specific post-marketing surveillance systems have been developed to monitor abuse of prescription drugs in some countries. The purpose of this review is to list and to describe post-marketing surveillance systems, according their methodology, in France and in foreign countries. These programs are based on adverse effect notifications, medical or legal consequences of abuse, general or specific population-based survey, professional networks or medication databases. Some programs use simultaneously several information sources. In conclusion, the multifaceted nature, the diversity and the inventiveness of post-marketing surveillance systems reflects the complexity of the abuse issue.

Patterns of methylphenidate use and assessment of its abuse and diversion in two French administrative areas using a proxy of deviant behaviour determined from a reimbursement database: main trends from 2005 to 2008

BACKGROUND

Methylphenidate is a psychostimulant drug indicated for the treatment of attention-deficit hyperactivity disorder (ADHD). Its abuse and diversion have been previously described in specific populations, such as students; however, few studies investigating abuse and diversion among the overall population are available.

OBJECTIVES

The aim of this study was to describe patterns of methylphenidate use and to explore the magnitude of its abuse and diversion in two French administrative areas using data from a reimbursement database. A proxy of 'deviant behaviour' was used for the abuse and diversion of methylphenidate, defined using the following parameters: total number of defined daily doses (DDDs) of methylphenidate dispensed; number of different pharmacies seen for dispensing of methylphenidate; number of prescribers consulted for a prescription of methylphenidate; and number of dispensings of methylphenidate. Data from the reimbursement database were analysed by clustering methods. These data were assessed from 2005 to 2008.

METHOD

The French General Health Insurance System (GHIS) database was used to obtain data on methylphenidate use in two French administrative areas. Individuals affiliated to the GHIS who had a prescription for methylphenidate reimbursed between 1 January and 31 March of 4 selected years (2005, 2006, 2007 and 2008) were included. After the first dispensing of methylphenidate for these individuals, all their dispensings (including methylphenidate and other psychoactive drugs) were monitored over a 9-month period. Following a descriptive analysis, a clustering method was used to identify different subgroups of subjects according to the methylphenidate consumer profile characteristics.

RESULTS

With regard to the number of patients who had a dispensing for methylphenidate during the first quarter of the year, an 84% increase was observed between 2005 (n = 640) and 2008 (n = 1175). The clustering method identified two subgroups. One of them was characterized by a higher number of dispensings, different prescribers and pharmacies and a greater total dispensed quantity, suggesting a deviant behaviour and, thus, possible abuse and diversion of methylphenidate. These subjects were older (aged 35.4 ± 11.3 years) and were more frequently patients receiving benzodiazepines, antidepressants, antipsychotics and maintenance opioid treatment. The proportion of subjects with a deviant behaviour increased from 0.5% in 2005 to 2% in 2007 and then decreased to 1.2% in 2008.

CONCLUSION

This method was able to assess the magnitude of methylphenidate abuse liability and to follow its evolution. The decrease in methylphenidate abuse and diversion seen between 2007 and 2008 can be explained by the enactment in April 2008 of specific regulations for prescription drugs (such as methylphenidate) that are deemed by the French government to have the potential for misuse; these regulations require the establishment of a 'contract of care' between the GHIS, prescriber and patient.

Which indicators can public health authorities use to monitor prescription drug abuse and evaluate the impact of regulatory measures? Controlling High Dosage Buprenorphine abuse

BACKGROUND

Two methods have been recently developed from a drug reimbursement database to provide useful indicators for public health authorities concerning the abuse potential of psychotropic drugs. The doctor-shopping indicator (DSI) measures the proportion of the drug obtained by doctor shopping among the overall quantity of the drug reimbursed and the clustering method reveals subgroups of deviant patients.

OBJECTIVE

The objective of the study was to analyze and compare indicators resulting from these two methods, applied to High Dosage Buprenorphine (HDB) (a product well-known to be diverted in France), in order to determine which public health authorities needs they answer.

DATA ANALYSIS

The patients with reimbursed HDB were grouped using the clustering method in terms of drug dispensations characteristics over a nine month period. The characteristics of the resulting subgroups, including their DSI, were then compared.

RESULTS

4787 Patients (73.4%) had no measurable doctor-shopping behaviour. But the comparison of the two methods demonstrated that the more a patient's profile was characterized by deviant behavior, the higher was the DSI: from 0.4% in a subgroup with a median profile to 72% in a subgroup with a deviant profile.

CONCLUSION

These two methods are useful surveillance tools for public health authorities: the clustering method may help devise pertinent intervention strategies to reduce prescription drug abuse while the DSI method provides quantitative information demonstrating whether these strategies are useful. We discuss the advantages and disadvantages of using these two methods as useful indicators for public health authorities.

Evidence of clonazepam abuse liability: results of the tools developed by the French Centers for Evaluation and Information on Pharmacodependence (CEIP) network

Recent observations suggest the existence of clonazepam abuse. To determine its importance in France, a quantitative and systematic synthesis of all clonazepam data of several epidemiological tools of the Centers for Evaluation and Information on Pharmacodependence (CEIP) network has been performed in comparison with data on others benzodiazepines (BZD). Data on clonazepam and other BZD have been analysed from different epidemiological tools: OSIAP survey that identifies drugs obtained by means of falsified prescriptions, Observation of Illegal Drugs and Misuse of Psychotropic Medications (OPPIDUM) survey that describes modalities of use and data from regional French health reimbursement system. In OSIAP survey, the proportion of clonazepam falsified prescriptions among all BZD falsified prescriptions increased. During the 2006 OPPIDUM survey, the analysis of the BZD modalities of use highlights clonazepam abuse liability (for example 23% of illegal acquisition), in second rank after flunitrazepam. Studies based on data from the French health reimbursed system show that 1.5% of subjects with clonazepam dispensing had a deviant behaviour. Among BZD, clonazepam has the second most important doctor-shopping indicator (3%) after flunitrazepam. All these data provide some arguments in favour of clonazepam abuse liability in real life and the necessity to reinforce its monitoring.

Pharmacoepidemiological research using French reimbursement databases: yes we can!

PURPOSE

To describe the reimbursement databases available in France for pharmacoepidemiological research and their use.

METHODS

France has a publicly funded health system that systematically covers the population. Within this system, three main insurance schemes provide health services to citizens in France and each have their own reimbursement database. Together these three databases cover almost 97% of the French population (respectively for 54.5, 3.6, and 3.3 million individuals, and a total of 61.4 million individuals). Data in these concern patients, prescribers, all the medical acts reimbursed, prescription and undertaking of laboratory tests (but without results), private hospital data, partial public hospital data and vital status. Their use is regulated but access is free and the data are anonymous. PubMed and Scopus were searched for relevant studies published from January 1988 to June 2009.

RESULTS

110 published studies were included. The topics and the study characteristics were extremely wide-ranging. The studies assessed patterns of drug use, have tested interventions, supported or improved prescribing practices, tested compliance with the French governmental Health guidelines, assessed physicians' prescribing practices and performed economic and cost-effectiveness assessments. The number of articles published increased greatly between 2002 and 2003.

CONCLUSIONS

The French reimbursement databases were greatly used over the last 20 years. They can provide data on exposure to drugs and can be used to study patterns of drug utilization although their limitations must be considered.

Estimation of clonazepam abuse liability: a new method using a reimbursed drug database

Some observations suggest the existence of clonazepam abuse. The aim of this study was to assess its magnitude in real life by a new method, using a prescription database, and to assess its evolution between 2001 and 2006. Individuals from a region affiliated to the French health reimbursement system, who had a prescription of clonazepam reimbursed between 1 January and 15 February of two selected years were included. Their deliveries were monitored over a 9-month period. After a descriptive analysis, a clustering method illustrated by a factorial analysis was used to identify different subgroups of clonazepam consumers. An increase of 82% in participants who had a delivery of clonazepam between 2001 and 2006 was observed. Using the clustering method, this study identified some deviant participants. This group comprises a higher proportion of males, benzodiazepine users, and buprenorphine users. The number of deliveries by different prescribers and pharmacies are higher. The proportion of deviant participants increased between 2001 and 2006 (from 0.86 to 1.38%). Our method can be used to assess the magnitude of abuse liability of clonazepam and is also interesting for following its evolution, two important keys for assessing patterns of abuse.

[Creating and validating a tool able to detect fraud by prescription falsification from health insurance administration databases]

GOAL

Make it possible to spot falsified prescriptions which were delivered and reimbursed.

METHOD

1- Use health insurance administration data bases to single patients liable to suspicion of fraud (repeated presentations of the same prescription to several pharmacies the same day) 2- Attribution of a diagnosis of fraud, by the CEIP (Center of Evaluation and Information about Pharmacodependence) based on transferred data, and by the medical department analysis of the complete file, and convocation when applicable 3- Calculation of quantitative performance of the tool.

RESULTS

We have singled 2030 patients. Among them 25 were able to get 553 deliveries out of 288 pharmacies from 114 prescriptions in one year. Our tool specificity is 99.5% and its sensitivity 69.4%.

CONCLUSION

Creating this tool which can become automatic and used on a large scale, brings a new light in the evaluation, by making hindsight fraud detection possible.

Survey of Forged Prescriptions to Investigate Risk of Psychoactive Medications Abuse in France

OBJECTIVE

To describe patterns of drug diversion from 2001 to 2004 in France and to define different profiles of forged prescriptions.

METHODS

Data from a national cross sectional survey carried out each year since 2001 were analysed. A national network of community pharmacies is requested to collect suspect prescriptions during two periods each year in May and November. Data included were date, age and sex of the patient, type of prescription form, drugs and criteria of suspicion.

RESULTS

Between 2001 and 2004, a sample of 1710 abnormal prescription forms were analysed. These concerned women in 54% of cases. The average age of those sampled was 47 years. Sixty-one percent of the 597 varieties of medication belonged to the anatomic therapeutic chemical (ATC) nervous system class. The most frequently involved drugs were benzodiazepines and benzodiazepine analogues (flunitrazepam, zolpidem) or opioids (buprenorphine, morphine). Multiple correspondence analysis underlined two opposite profiles for suspicious prescriptions: (i) specific prescription forms for scheduled drugs presented by men aged <45 years involving drugs for the nervous system and presenting the criteria of stolen, falsified and abnormal prescriptions; and (ii) prescription forms presented by women aged >45 years involving cardiovascular and muscular-skeletal system drugs, presenting the criteria of alteration to the prescription.

CONCLUSION

Analysis of data collected from community pharmacies in the OSIAP (Ordonnances Suspectes Indicateur d'Abus et de Pharmacodépendance) survey gives information about patterns of diversion of medication in France. This system is able to evaluate the impact of measures implemented in order to decrease the misuse of drugs and able to identify new patterns of drug diversion. Identification of profiles of suspicious 'prescription forms' could help pharmacists to better identify abnormal prescriptions. A European project has recently been implemented to extend this kind of survey to other countries in Europe.

Détournement d’usage du clonazépam (Rivotril®) : tendances récentes

Recent observations suggest the existence of clonazepam abuse. In order to determine the importance of this practice and the characteristics of these consumers, a study has been carried out, based on data from the Provence-Alpes-Côte-d'Azur and Corsica health reimbursement system. Individuals from these regions affiliated to the French health reimbursement system, who have had a prescription of clonazepam reimbursed between January 1, 2001 and February 15, 2001, have been selected. The deliveries have been monitored over a 9 month-period. 9381 subjects have been selected. A sub-group of 1.5 per cent subjects with a deviant behaviour has been identified by factorial analysis and has been compared to the sub-group without deviant behaviour. The subjects with deviant behaviour are younger and mostly male. The dosage of clonazepam is higher (10.8 mg per day versus 2.1 mg per day) with a significantly higher proportion of benzodiazepine and high-dose buprenorphine. The number of deliveries is higher (19.4 versus 5.9) as well as the number of different physicians (4.5 versus 1.5) and pharmacies (5.9 versus 1.3). This study provides some arguments in favor of the potential of abuse and dependence of clonazepam and the necessity to reinforce its monitoring. This information requires to be relayed to health professionals.