A comparison of benzodiazepine and related drug use in Nova Scotia and Australia

Translating Benzodiazepine Utilization Data into Meaningful Population Exposure: Integration of Two Metrics for Improved Reporting

Drug utilization research on benzodiazepines remains important for measuring trends in consumption within and across borders over time for the sake of monitoring prescribing patterns and identifying potential population safety concerns. The defined daily dose (DDD) system by the World Health Organization (WHO) remains the internationally accepted standard for measuring drug consumption; however, beyond consumption, DDD-based results are difficult to interpret when individual agents are compared with one another or are pooled into a total class-based estimate. The diazepam milligram equivalent (DME) system provides approximate conversions between benzodiazepines and Z-drugs (i.e. zopiclone, zolpidem, zaleplon) based on their pharmacologic potency. Despite this, conversion of total dispensed benzodiazepine quantities into DME values retains diazepam milligrams as the total unit of measurement, which is also impractical for population-level interpretation. In this paper, we propose the use of an integrated DME-DDD metric to obviate the limitations encountered when the component metrics are used in isolation. Through a case example, we demonstrate significant change in results between the DDD and DME-DDD method. Unlike the DDD method, the integrated DME-DDD metric offers estimation of population pharmacologic exposure, and enables superior interpretation of drug utilization results, especially for drug class summary reporting.

Differences in utilisation of gastroprotective drugs between 2001 and 2005 in Australia and Nova Scotia, Canada

PURPOSE

This study aimed to compare use of histamine H2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs), 2001-2005, in the elderly and social security beneficiaries in Australia (AUS) and Nova Scotia, Canada (NS).

METHODS

Prescription dispensing data were collected for all subsidised H2RAs and PPIs. In AUS, dispensing data for concession beneficiaries were obtained from the Pharmaceutical Benefits Scheme database. In NS, data were sourced from the Pharmacare database. Relevant population data were used to convert to World Health Organisation Anatomic Therapeutic Chemical defined daily doses (2005) per 1000 beneficiaries per day (DDD/1000/day).

RESULTS

Overall use of gastroprotective agents was similar and rising in NS and AUS (100-160 DDD/1000/day) over this 5-year time window. However, the proportion of this use accounted for by PPIs was far higher in AUS (over 85% by 2005) than in NS (23% rising to 35% over the 5 years). In AUS, PPI use rose from 50 to about 140 DDD/1000/day over the 5 years, whereas PPI use in NS rose slowly to less than 60 DDD/1000/day by 2005. H2RA use in NS was always high (over 100 DDD/1000/day), whereas in AUS, H2RA use fell from 54 to around 24 DDD/1000/day over this period.

CONCLUSIONS

AUS had much higher use of PPIs than NS over 2001-2005. The proportion of PPIs in all gastroprotective agents rose in AUS to be nearly 90%. The differences in utilisation during this time window could lead to differences in health outcomes from either lower gastro-intestinal bleeding risk or higher long-term adverse effects of PPIs.

Benzodiazepines revisited--will we ever learn?

AIMS

To re-examine various aspects of the benzodiazepines (BZDs), widely prescribed for 50 years, mainly to treat anxiety and insomnia. It is a descriptive review based on the Okey Lecture delivered at the Institute of Psychiatry, King's College London, in November 2010.

METHODS

A search of the literature was carried out in the Medline, Embase and Cochrane Collaboration databases, using the codeword 'benzodiazepine(s)', alone and in conjunction with various terms such as 'dependence', 'abuse', etc. Further hand-searches were made based on the reference lists of key papers. As 60,000 references were found, this review is not exhaustive. It concentrates on the adverse effects, dependence and abuse.

RESULTS

Almost from their introduction the BZDs have been controversial, with polarized opinions, advocates pointing out their efficacy, tolerability and patient acceptability, opponents deprecating their adverse effects, dependence and abuse liability. More recently, the advent of alternative and usually safer medications has opened up the debate. The review noted a series of adverse effects that continued to cause concern, such as cognitive and psychomotor impairment. In addition, dependence and abuse remain as serious problems. Despite warnings and guidelines, usage of these drugs remains at a high level. The limitations in their use both as choice of therapy and with respect to conservative dosage and duration of use are highlighted. The distinction between low-dose 'iatrogenic' dependence and high-dose abuse/misuse is emphasized.

CONCLUSIONS

The practical problems with the benzodiazepines have persisted for 50 years, but have been ignored by many practitioners and almost all official bodies. The risk-benefit ratio of the benzodiazepines remains positive in most patients in the short term (2-4 weeks) but is unestablished beyond that time, due mainly to the difficulty in preventing short-term use from extending indefinitely with the risk of dependence. Other research issues include the possibility of long-term brain changes and evaluating the role of the benzodiazepine antagonist, flumazenil, in aiding withdrawal.

The utilization of antidepressants and benzodiazepines among people with major depression in Canada

OBJECTIVE

Although clinical guidelines recommend monotherapy with antidepressants (ADs) for major depression, polypharmacy with benzodiazepines (BDZs) remains an issue. Risks associated with such treatments include tolerance and dependence, among others. We assessed the prevalence and determinants of AD and BDZ utilization among Canadians who experienced a major depressive episode (MDE) in the previous 12 months, and determined the association of seeing a psychiatrist on the utilization of ADs and BDZs.

METHOD

Data were drawn from the 2002 Canadian Community Health Survey: Health and Well-Being, a nationally representative sample of Canadians aged 15 years and older. Descriptive statistics quantified utilization, while logistic regression identified factors associated with utilization, such as sociodemographic characteristics or type of physician seen. Sampling weights and bootstrap variance estimations were used for all analysis.

RESULTS

The overall prevalence of AD and BDZ utilization was 49.3% of respondents who experienced an MDE in the past 12 months and reported AD use. Key determinants of utilization were younger age and unemployment in the past week (OR 2.6; P < 0.001). Being seen by a psychiatrist increased utilization (OR 2.5; P < 0.001), possibly because psychiatrists were seeing patients with severe depression.

CONCLUSION

A large proportion of people with past-year MDEs utilized ADs and BDZs. It is unclear how much of this is appropriate given that evidence-based clinical guidelines recommend monotherapy with ADs in the treatment of major depression.

Improving the use of benzodiazepines--is it possible? A non-systematic review of interventions tried in the last 20 years

Background

Benzodiazepines are often used on a long term basis in the elderly to treat various psychological disorders including sleep disorders, some neurological disorders and anxiety. This is despite the risk of dependence, cognitive impairment, and falls and fractures. Guidelines, campaigns and prescribing restrictions have been used to raise awareness of potentially inappropriate use, however long term use of benzodiazepine and related compounds is currently increasing in Australia and worldwide. The objective of this paper is to explore interventions aimed at improving the prescribing and use of benzodiazepines in the last 20 years.

Methods

Medline, EMBASE, PsychINFO, IPA were searched for the period 1987 to June 2007.

Results

Thirty-two articles met the study eligibility criteria (interventions solely focusing on increasing appropriate prescribing and reducing long term use of benzodiazepines) and were appraised. Insufficient data were presented in these studies for systematic data aggregation and synthesis, hence critical appraisal was used to tabulate the studies and draw empirical conclusions. Three major intervention approaches were identified; education, audit and feedback, and alerts.

Conclusions

Studies which used a multi-faceted approach had the largest and most sustained reductions in benzodiazepines use. It appears that support groups for patients, non-voluntary recruitment of GPs, and oral delivery of alerts or feedback may all improve the outcomes of interventions. The choice of outcome measures, delivery style of educational messages, and requests by GPs to stop benzodiazepines, either in a letter or face to face, showed no differences on the success rates of the intervention.

The contribution of injecting drug users in Sydney, Melbourne and Brisbane to rising benzodiazepine use in Australia 2000 to 2006

OBJECTIVE

To determine whether the increased utilisation of benzodiazepines in Australia from 2000 to 2006 could be accounted for by the increased use of benzodiazepines among those who inject heroin

METHOD

Areas known to have high numbers of injecting drug users, (IDU) in Sydney, Melbourne and Brisbane, Australia were identified. Data were obtained from the Medicare and the Drug Utilization Sub-Committee databases on all benzodiazepines dispensed to concession beneficiaries in the chosen areas and Australia as a whole. The utilisation of benzodiazepines was calculated in defined daily dose per 1000 (DDD/1000) beneficiaries and for IDU/day using the estimated numbers of IDU, from 2000-2006.

RESULTS

The utilisation of benzodiazepines increased by 22% for all Australian concession beneficiaries but in areas with a high proportion of IDU, the utilisation of benzodiazepines decreased.

CONCLUSIONS

In areas known to have a high proportion of IDU, the concession beneficiary use of benzodiazepines was estimated to be largely accounted for IDU usage. However, the overall increase in benzodiazepine utilisation by Australian concession beneficiaries from 2000 to 2006 was not primarily driven by use among IDU who only accounted for a small proportion of total benzodiazepines use.

IMPLICATIONS

It appears that sub-groups of the populations, other than IDU may be responsible for the increase in benzodiazepine use by concession beneficiaries.

An intervention to improve benzodiazepine use--a new approach

OBJECTIVE

To design, implement and evaluate a novel intervention, utilizing electronic media, to improve benzodiazepine use in specific geographical areas in Australia.

METHODS

An educational intervention about benzodiazepine use, using email, a website and bookmarks, targeted consumers, GPs, nurses (in aged care facilities) and pharmacists in two areas in Australia over a 6-month period. Two control areas, which received no aspect of the intervention, were used to compare and contrast. A drug use evaluation was conducted in aged care facilities before and after the study (in the intervention areas) and after the intervention (in the control areas) to assess quality of benzodiazepine use. Benzodiazepine dispensing data were obtained for each area before, during and after the intervention to quantitate use. Interviews were conducted with nurses and pharmacists involved in the intervention and website statistics were recorded.

RESULTS

A significantly smaller number of aged care residents were on benzodiazepines for 6 months or more (P < 0.05) after the intervention compared with before. However, other indices, such as number of residents taking benzodiazepines or taking them for a long time, did not change significantly before compared to after the intervention and there were no significant differences between the control and intervention areas after the intervention. Quantitative use of benzodiazepines did not change after the intervention. Many health care professionals in the intervention areas remembered seeing the electronic educational material for benzodiazepines. The website was viewed 115 times during the study.

CONCLUSIONS

The study was easy and inexpensive to administer and attracted high participation rates by health care professionals. There was a change in the use of benzodiazepines in aged care facilities (less long-term benzodiazepine use) in the intervention areas. The electronic educational materials (emails and website) were read and informations (especially the key messages) were able to be recalled after the intervention. However, no large changes in benzodiazepine overall use (either between control and intervention areas or before and after the intervention) were recorded.

Usage of benzodiazepines: A review

Abstract Purpose. The use of benzodiazepines remains a source of controversy. Some prescribers believe that they are beneficial and espouse their use; others regard their risk:benefit ratio as too adverse for any but occasional use. This review considers these viewpoints based on the appropriate literature. Survey. The recent English-language literature relating to this topic was surveyed. The publications proved too heterogeneous for a formal meta-analysis, so a descriptive review is provided. Overview. Surveys of benzodiazepine use provide data mainly from the UK, Europe and North America. Prescribing patterns varied widely but long-term usage is common and sometimes the norm. Conclusions. Long-term prescription of benzodiazepines still takes place despite general warnings from the medical and other professions and drug regulatory bodies that long-term use is unjustified both from the lack of a systemic database establishing such efficacy and a large literature documenting the risks of long-term usage, such as dependence. The young and the old are particularly at risk. Continued monitoring is essential, but the regulatory authorities may need to take a more active role in curbing such undesirable practice.

Patterns in the use of benzodiazepines in British Columbia: examining the impact of increasing research and guideline cautions against long-term use

OBJECTIVE

We examined changes in patterns of benzodiazepine use in British Columbia over a period of increasing evidence of harms associated with long-term use.

METHODS

Using linked administrative databases for the years 1996 and 2006, we performed logistic regression to examine how socio-economic and health factors affect the likelihood of benzodiazepine use and long-term use, and to test for changes in rates of use and long-term use over time.

RESULTS

In 2006, 8.4% of British Columbians used benzodiazepines, 3.5% long-term. Use was positively related with being female, lower income, older, and of poorer health status. Long-term use was positively associated with being in the lowest income quintile, of poorest health, and over the age of 65. While the rate of long-term use decreased from 1996 to 2006 for those over age 70, it increased in middle-aged populations.

CONCLUSIONS

Our results suggest, despite increased awareness of and cautions regarding risks associated with long-term use of benzodiazepines, rates of potentially inappropriate use have changed very little over a decade. Given that early use of benzodiazepines is positively associated with later long-term use, policies targeting populations younger than conventionally studied (i.e. those under age 65) may be needed to decrease rates of long-term use.

How do different age groups use benzodiazepines and antidepressants? Analysis of an Australian administrative database, 2003-6

BACKGROUND

The use of antidepressants and benzodiazepines is increasing in Australia and worldwide, and it is thought that some of the prescribing of these classes of drugs may be inappropriate. However, the demographic characteristics of the subgroups of the population responsible for this increase remain unexplored.

OBJECTIVE

The aim of this study was to examine changes in the utilization of antidepressants and benzodiazepines between different age groups within Australia from 2003 to 2006.

METHODS

The Australian Pharmaceutical Benefits Scheme administrative database was used to obtain dispensing data for all antidepressants and publicly subsidized benzodiazepines. Changes in utilization (amounts and patterns of use of different compounds) were compared between different age groups from 2003 to 2006. The WHO Anatomic Therapeutic Chemical/Defined Daily Dose system was used.

RESULTS

Use of antidepressants increased from 2003 to 2006, and in each year increased with age, with those > or = 65 years having the greatest use. Differences were seen in the antidepressant most utilized, with the elderly using more tricyclic antidepressants than those who are younger. The utilization of benzodiazepines decreased from 2003 to 2006 in elderly individuals and those receiving social welfare benefits. Individuals aged > or = 85 years had the highest use of benzodiazepines and used more long-acting benzodiazepines compared with those aged 35-44 years.

CONCLUSION

The elderly still account for most use per capita of benzodiazepines. Some of this use may be inappropriate (e.g. use of long-acting benzodiazepines) and, hence, may represent a useful target for future educational intervention. The elderly also still account for the largest per capita use of antidepressants.