Renewal rates of filled antidepressant and antidementive prescriptions in the total population of Austria: A record linkage study 1 Katschnig ,
2 Endel ,
1 Straßmayr ,
3 Endel
Heinz Florian Christa Gottfried 1Ludwig Boltzmann Institute for Social Psychiatry and IMEHPS.research, Vienna, Austria, 2Technical University of Vienna, 3Main Association of Austrian Social Security Institutions Correspondence:
[email protected]
Abstract Background Psychotropic prescriptions are dramatically on the increase in industrialized countries. However, this does not necessarily mean that more persons receive psychopharmacological treatments, it could also be that they are more correctly prescribed, i.e. not just as once-only acts, but as repeated prescriptions, which is necessary to see whether they work. This is especially true for antidepressant and antidementia drugs, were single prescriptions make no sense from a clinical perspective. Objective To elucidate renewal rates of first filled prescriptions for antidepressant and antidementia prescription for the total population of the country of Austria by using record linkage methods. Methods Austria (population 8.3 million) has a mandatory health insurance system with more than 95% of the population covered, however, with 19 different health insurance organisations with different reimbursement and data recording systems. Data are in the process of being harmonized for the years since 2006 into a single data base, in order to carry out record linkage studies. For the present study two patient cohorts for filled prescriptions in the 4th quarter 2006 (antidepressants ATC N06A, antidementives N06D) were selected and analysed in terms of further prescriptions until the end of 2007.
Background Psychopharmacological prescriptions are on the increase worldwide. For antidementia compounds the aging population can explain some of the increase in prescribing. It is not so easy to explain why the consumption of antidepressants has doubled since 2000 (OECD 2013). The US National Centre for Health Statistics reported that 11% of Americans aged 12 and above were taking antidepressants in 2005-2008 (Pratt et al 2011).
Results 424.281 persons (=5% of the total Austrian population) were identified as having had at least one antidepressant prescription in Q4/2006, and for 144.557 patients this was the case for antidementives. In the antidepressant group an astonishingly high percentage of patients (4.6%) had died before the end of 2007 (antidementives: 6%) and were excluded from follow up. For patients who had no previous prescriptions in 2006 ("new prescriptions" of antidepressants: N=61.357; antidementives: N=26.148), the main finding was that the non-renewal rates are very high, 33% in the antidepressant and 38% in the antidementive group. Only a small proportion of patients had prescriptions refilled over several months, which would be the only clinically meaningful use of these compounds. The old tricyclic antidepressants had higher discontinuation rates than the serotoninereuptake inhibitors, the acetylcholinesterase inhibitors had the lowest non-renewal rates. Psychiatrist and general practitioners had by and large similar rates, non-psychiatric specialists had the highest rates for all types of medication studied here. Conclusion The analysis of large administrative data sets by record linkage can significantly supplement knowledge based on clinical studies. The low rates of repetition of filled prescriptions for drugs meant to be applied for longer time periods need further analyses of determining factors, both on the prescriber and the patient side. Whether this situation has changed recently and the rise in psychotropic prescriptions can at least be partly explained by a higher rate of continuous prescriptions rather than by more people being put on psychotropics, will be the topic of a follow-up study of the present research.
Methods
Results
Austria (population 8.3 millions) has a mandatory health insurance system with more than 95% of the population covered. Primary care and specialist outpatient services are provided by single-handed doctors who have contracts with some or all of the 19 mandatory health insurance companies and are mostly paid by feefor-service. UPI data are collected electronically for all visits to these doctors and for filled pharmaceutical prescriptions since 2006. Hospital episodes (paid by a DRG-System) are electronically documented without UPIs. In an ongoing process these records are being linked by deterministic, probabilistic and other linkage methods. For the present study a full linked data set was available for the years 2006 and 2007. The database contains all types of providers. The Austrian Linked Health Service Utilization Data Base (GAP-DRG) 2006-2007 covers all relevant health care domains
Primary care data Specialist OP care data
GAP-DRG data base
1. Overall results The main finding is that the non-renewal rate is very high: For 33,2% patients in the antidepressant group and 38% in the antidementive group no single further specific prescription was filled during the subsequent 12 to 15 months. If 1 and 2 additional prescriptions are included (which would also be far away from a clinically meaningful practice), these percentages rise to 55.8% in the antidepressant and 57.4% in the antidementive group. In sum, less than one third of patients have received their medication as suggested in clinical guidelines over several months..
2. Subtypes of medication Among the antidepressants the old tricyclic ones (which still made up 5% of all antidepressants in 2006) had nearly double the rate of no further prescriptions than the SSRIs and other antidepressants (if up to 2 further prescriptions were added, discontinuation rates reaches over 80%). The bulk of antidementives were Gingko prescriptions (reimbursed by the Austrian mandatory health insurance) which had more than twice the non-renewal rate of the core antidementives (acetylcholinesteraseinhibitors and memantine).
Hospital episode data Filled prescription data 57,4
For antidepressants cost concerns and issues of the appropriateness of the pharmacological approach are topics of an ongoing discussion related to the dramatic increase of prescriptions (e.g. Kirsch et al 2008, Goodle 2013, Dowrick & Frances 2013, Adli & Hegerl 2013). However, It has been suggested recently that much of the increase in prescriptions of antidepressants does not necessarily mean that more people are treated, but that the adherence to guidelines has increased, which require repeated prescription over a certain time period (Moore et al 2009).
For the present study two patient cohorts with first filled prescriptions in the 4th quarter 2006 (one for antidepressants=ATC:N06A, one for antidementives=ATC: N06D) were selected and analysed in terms of the numbers of subsequently filled prescriptions for the same type of drug for each patient until the end of 2007 (12 to 15 months follow-up), excluding patients who had died before the end of follow-up. Type of the first prescribing physician and main subtypes of antidepressant (tricyclic = TCA, vs selective serotoninreuptakeinhibitors etc. = SSRI etc.) and antidementives (Acetylcholinesterase-Inhibitors/Memantin = AChEI/MEM vs Ginkgo) were included in the analysis. Co-prescriptions between antidepressants and antidementives were not studied here.
Objectives
Study populations
The study attempts to contribute data of prescribing patterns from a large countrywide routine database in Austria to inform the recently heated up controversy on the rising prescriptions of psychotropic medication. The objective was to identify and compare prescription patterns for antidepressant and antidementia medication by outpatient psychiatrists and general practitioners in a country with free access to both types of doctors working in single handed practices (without a gatekeeping system) and elucidate the renewal rates for such prescriptions after the first prescription in a defined time period.
424.281 persons (6% of the Austrian population aged 15+) were identified as having had at least one antidepressant prescription filled between 1 October and 31 December 2006, and for 144.557 patients this was the case for antidementives. (nearly 10% of the population aged 65+). 404.281 patients with antidepressant and 135.861 with antidementia prescriptions did not die before the end of 2007 and were included in the follow-up study. Results are reported here only for patients who had a first prescription in the last quarter of 2006 (antidepressants: N=61.357; antidementives: N=26.148).
Conclusion Record linkage of prescription data for the total population of Austria showed that in 2006/2007 non-renewal rates of first prescriptions of antidepressant and antidementives were extremely high. The bulk of these prescriptions came from general practitioners, whose non-renewal rates, however, were only slightly higher than those of psychiatrists, with non-psychiatric specialists having by far the highest discontinuation rates. It is unclear what the reason for the high non-renewal rate is. A follow up of this study is planned which will show whether the recent increase of antidepressant prescriptions can at least partly be explained by an increase of continued prescription of these drugs.
3. Prescribing physicians More than two third of the prescriptions for both antidepressants and antidementives came from general practitioners. Contrary to expectation they had only slightly higher discontinuation rates than the psychiatrists. However, we found that non-psychiatric specialists (consultants) who in Austria are mostly working in single-handed practices and have high prescriptions numbers of psychotropics have the highest non-renewal rates.
References Adli M & Hegerl U: Do we underestimate the benefits of antidepressants? The Lancet 2014;383:1361-1362 Godlee F: Don’t keep taking the tablets. BMJ 2013;347:f7438 (11 December) Dowrick C, Frances A: Medicalising unhappiness: new classification of depression risks more patients being put on drug treatment from which they will not benefit. BMJ 2013;347:f7140 (9 December) Kirsch I, Deacon BJ, Huedo-Medina TB , Scoboria A, Moore TJ, Johnson BT: Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration. PLoS Med 2008;5(2):e45. Moore M, Yuen HM, Dunn N, Mullee MA, Maskell J, Kendrick T: Explaining the rise in antidepressant prescribing: a descriptive study using the general practice research database. BMJ 2009;339:b3999 OECD: Pharmaceutical consumption, in Health at a Glance 2013: OECD Indicators, OECD Publications Pratt LA, Brody DJ, Gu Q: Antidepressant Use in Persons Aged 12 and Over: United States, 20052008. NCHS Data Brief. 2011:76
