Methods in pharmacoepidemiology

Assessing the benefit-risk balance of drugs. Some lessons from the COVID pandemic

INTRODUCTION

Drug efficacy and effectiveness are assessed respectively through clinical trials and pharmaco-epidemiological studies. However, relative and absolute benefits of drugs are distinct measures that must be considered in relation to the baseline risk of disease incidence, complication or progression. On the other hand, adverse drug reactions are independent of the basic risk but depend on the characteristics of the population treated. Given these prerequisites, how can we balance the benefits and risks of drugs?

AREAS COVERED

We use the example of therapeutics evaluated during Covid to describe how assessing the benefit-risk balance of drugs is a complex process.

EXPERT OPINION

Clinical trials are not designed to identify rare adverse events, underscoring the necessity for a pharmacovigilance system. Evaluating the balance between the benefits and risks of drugs is an ongoing process, demanding the simultaneous analysis of data from clinical trials, potential drug-drug interactions, pharmacovigilance monitoring and pharmaco-epidemiological studies, to identify potential safety concerns. In addition, pharmacologists must play a major role in educating the general public about drugs, aiding in the accurate interpretation of the benefit-risk balance and preventing misinformation.

Use of psychotropic drugs in the elderly in France: Are we condemned to remain at high tide?

Psychotropics are widely used drugs, especially in the elderly, especially in France. This, and the risks associated to their use, logically led to concerns that resulted in numerous studies, reports, and regulatory actions intending to limit this use. This review objective was to provide an overview of psychotropic use in elderly subjects in France for antipsychotics, antidepressants, and benzodiazepines and related drugs. The narrative review performed is structured in two parts. The first reminds the initial steps of psychotropic use monitoring in the general French population. The second provides information on psychotropic use in elderly in France using the latest open data released by the French Health Insurance system and processed using the dedicated DrugSurv tool developed within the DRUGS-SAFE® and DRUGS-SAFE® programs. This was completed examining the most recent studies regarding psychotropic use in elderly in France, whether they consisted in publications or reports. At least before the COVID-19 epidemic, decreases in psychotropic prevalence of use among the elderly in France could be observed, mostly for antipsychotics or benzodiazepines (e.g. antipsychotics, 2006-2013: 10.3% decrease and benzodiazepines 2012-2020: decrease from 30.6% to 24.7% in subjects aged ≥65). Psychotropic prevalence of use remained however very high overall (e.g. antidepressants, 2013: 13% in subjects aged 65-74 and 18% in aged ≥65), exceeding that of most other countries, with a significant proportion of inappropriate use (e.g. in 30% of benzodiazepine users, all ages) carrying a clearly identified risks for uncertain benefit. Initiatives have been multiplied at the national level to reduce psychotropic overuse in the elderly. The reported prevalences demonstrate their effectiveness is obviously insufficient. This limited effectiveness is not specific to psychotropics and might reside in a failure to create strong adherence to messages and recommendations. Other levels should be considered, especially regional, for interventions coupled with pharmacoepidemiologic monitoring allowing impact assessment.

Drug Therapy and Adherence in Patients With Coronary Heart Disease: Results of the Russian Part of the EUROASPIRE V International Multicenter Study

Aim      To study the practice of drug treatment of ischemic heart disease (IHD) and the consistency of this practice with the established guidelines.Material and methods  Results of the Russian part of the EUROASPIRE V study were compared with the general European population of the study. At ≥6 mos. and <2 years after the discharge from the hospital, patients were invited to visit the site for an interview. The drug therapy recommended upon discharge and taken by patients in the long-term as well as the patients' compliance with the treatment were analyzed. In Russian centers, 699 patients were registered, and 399 of them visited the centers for the interview.Results             Upon discharge from the hospital, patients of the Russian cohort and of the entire study population were prescribed acetylsalicylic acid or other antiplatelet drugs (99.2% and 94.1%, respectively); beta-blockers (87.2 and 81.6%, respectively); angiotensin-converting enzyme (ACE) inhibitors (69.9% and 61.1%, respectively); sartans (16.5% and 14.2 %, respectively); calcium channel blockers (19.3 and 19.4 %, respectively); nitrates (8.0% and 22.5 %, respectively); diuretics (31.1 and 32.5 %, respectively); statins (98.0% and 85.0 %, respectively); and anticoagulants (6.6 and 8.3 %, respectively). For the long-term treatment, patients of the Russian cohort and of the entire study population took antiplatelets (94.7 % and 92.5 %, respectively); beta-blockers (83.2% and 81.0 %, respectively); ACE inhibitors (60.2% and 57.3 %, respectively); sartans (19.3% and 18.4 %, respectively); calcium antagonists (21.1% and 23.0 %, respectively); nitrates (9.0% and 18.2 %, respectively); diuretics (31.8% and 33.3 %, respectively); statins (88.2% and 80.8 %, respectively); and anticoagulants (8.8% and 8.2 %, respectively). High intensity hypolipidemic therapy was prescribed to 54.0 % of patients in Russian centers and 60.3 % of patients in the entire study. Both Russian and international patients evaluated their compliance with the prescribed medication as high.Conclusion      According to results of the EUROASPIRE V study as compared to earlier studies, the practice of drug therapy in Russian patients with IHD has significantly approached European indexes. Further optimization is possible by a more extensive use of high intense hypolipidemic treatment and antidiabetic drugs with a documented positive effect on prognosis of cardiovascular diseases.

Evaluation of Covid-19 vaccines: Pharmacoepidemiological aspects

The marketing authorization granted to SARS-Cov-2 vaccines was accompanied by reinforced safety monitoring plans. These plans' implementation was part of the usual logic of post-marketing surveillance of new and innovative health products. It was especially adapted to the context of post-marketing monitoring of drugs developed according to the usual scientific quality standards but in an accelerated schedule. In Europe, the reinforced surveillance system relies on the complementary strengths of pharmacovigilance and pharmacoepidemiology. If the performances of pharmacovigilance monitoring are incomparable for the detection of safety signals relating to rare events of atypical presentation, it needs to be completed with pharmacoepidemiology activities for more common events, either multifactorial or frequently classified as idiopathic. The pharmacoepidemiological monitoring developed in Europe was elaborated before the first SARS-Cov-2 vaccines where marketed, taking into account the lessons learned from the vaccination campaign against 2009 A (H1N1) influenza. It includes numerous academic studies as well as studies performed within vaccines risk management plans. In terms of safety, those defined a priori mostly concerns a list of pre-established health events of specific interest. Aside of these planned activities, ad-hoc studies will be latter developed on purpose to investigate safety signals or potential signals that could be identified as the result of pharmacovigilance activities. Aside of these regulated activities, as for today, very few studies have been published regarding SARS-Cov-2 vaccines; most of the existing consist in preprints that should be considered with caution. Pharmacoepidemiology of vaccines is thought to allow near-real time monitoring that needs sufficient time to provide with valid results. In the constant urge for information that accompanies COVID-related science, it is important not to make haste the enemy of speed and to let pharmacoepidemiology provides with what it is expected to do: rock-solid scientific information contributing to evidence-based decision-making.

Drug safety in multiple sclerosis: From reporting to signal detection and benefit-risk management

BACKGROUND

Pharmacovigilance (PV) rules emerged in the late 60s-early 70s. Since that time, the World Health Organization Center for International Drug Monitoring carries out the corresponding tasks. Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system that generally starts in young adults between 20 and 40 years of age. Over the last 25 years, MS patients have benefited from the development of a plethora of disease modifying drugs (DMD). These changes in the therapeutic armamentarium have been associated with some serious adverse reactions challenging health authorities and neurologists involved in treatment and care for MS patients.

METHODS

The present review aims to describe, for MS DMDs, how adverse drug reactions are reported during clinical trials and the post-marketing period and how important signal detection and benefit-risk management have been in this disease until now. Several examples are reported to illustrate the different steps of PV processes.

CONCLUSION

Improvement of the PV system procedures has led to significant progress in the detection of signals, allowing better assessment of the benefit-risk balance and the implementation of risk management plans for MS treatments. The involvement of neurologists is essential to improve knowledge on the benefit-risk balance of these drugs. In addition, adverse drug reactions reporting by persons with MS should be encouraged.

An ontology of Pharmaceutical Services in the pages of Journal Ciência & Saúde Coletiva

Pharmaceutical Services (PS) is a growing field which has established itself over the last 25 years in Brazil through scientific publications. This work investigates the evolution of the field in the Brazilian periodical Journal Ciência & Saúde Coletiva. We conducted a scoping review of relevant literature produced in four separate periods (1996-2003, 2004-2010, 2011-2015, and 2016-2019). A search for articles that contained one or more of the pre-established key words in the title was performed by separate pairs of reviewers. The search resulted in 307 articles, 260 of which were included. The findings show that the number of publications increased steadily over the study period. The papers were predominantly open-topic and original articles and written in Portuguese. Most of the lead authors were from the South and Southeastern regions of Brazil and from public universities and Fiocruz. The predominant primary theme was medicine utilization (161 articles), followed by management (56), and tangential aspects of the PM cycle (43). An ontology of PS was created based on the classification of the articles. The findings show that the field of PS encompasses public policy and management and frontline activities involved in the delivery of health care to the population. It is hoped that the diverse range of interrelations in the field of PS will be increasingly addressed in future publications.

Pharmacovigilance - The next chapter

The discovery and quantification of adverse drug reactions has long relied on the careful analysis of spontaneously reported cases. Causality assessment (imputation) was a fundamental feature of individual case report analysis. This was complemented by analysis of aggregated cases, and of disproportionality analyses in spontaneous reports databases. In the absence of more specific information sources, these have resulted in the discovery of many new adverse reactions, altering drug information. It has led to the withdrawal from the market of many drugs, but its use for risk quantification remains fraught with uncertainty. The recent access to population-wide claims or electronic health records databases have confirmed for spontaneous reporting a predominant role in hypothesis generation for serious adverse drug reactions, notably those that result in hospital admission or death. In these cases, the events are identifiable at the population level, and can be quantified precisely using the tools of modern pharmacoepidemiology, to generate specific benefit-risk analyses. Spontaneous reporting remains irreplaceable in signal and alert generation in drug safety, despite its inherent limitations. For signal strengthening and assessment, more systematic and quantitative methods should be sought, such as claims databases for reactions resulting in hospital admissions.