Adverse drug reactions in elderly: a five-year review of spontaneous reports to the Portuguese pharmacovigilance system

Potential inappropriate medications and drug-drug interactions in adverse drug reactions in the elderly: a retrospective study in a pharmacovigilance database

Introduction

Potential inappropriate medications (PIMs) and potential drug-drug interactions (pDDIs) are important factors leading to adverse drug reactions (ADRs) in the elderly. This study aimed to evaluate the incidence and pattern of PIMs and pDDIs in the elderly based on a real-world pharmacovigilance database and identify the variables associated with them.

Methods

This retrospective study evaluated PIMs and pDDIs by updated Beers criteria and Lexi-Interact online, respectively, using ADRs reported for those aged ≥65 years submitted between 2011 and 2023 from a real-world database of a tertiary care teaching hospital. Correlation factors were investigated by binary and multiple logistic regression analyses.

Results

A total of 1,423 ADRs were included and involved 2,238 prescribed drugs; 54.11% of the total were men, and 23.47% were classified as serious. The most commonly implicated pharmacological group was antimicrobial agents. Aspirin and clopidogrel emerged as the drugs causing the majority of ADRs. PIMs were detected in 32.04% of all ADR reports. Aspirin and diclofenac were the most common active pharmaceutical ingredients involved, and gastrointestinal bleeding was the primary clinical manifestation of severe ADRs caused by PIMs or involved in PIM-related risk factors. Age, number of diagnosed diseases and prescribed drugs, ADR severity and preventability, hypertension, coronary heart disease, and arthritis were independent influencing factors of PIMs. Among 498 ADR reports with ≥2 prescribed drugs, 202 cases (14.20%) had pDDIs. Blood and hematopoietic organ and cardiovascular agents were the most commonly involved categories. The most frequent drug combinations in classes C, D, and X were aspirin-clopidogrel, aspirin-heparin, and potassium chloride-promethazine, respectively. The majority of pDDIs increased the risk of bleeding through pharmacodynamic mechanisms. The number of prescribed drugs and diagnosed diseases, ADR severity and preventability, stroke, diabetes, and coronary heart disease, along with PIM use, were independent predictors of pDDIs.

Conclusion

The incidence of PIMs and pDDIs was found to be relatively high in the elderly, especially in the treatment of cardiovascular and cerebrovascular diseases and non-steroidal anti-inflammatory drugs (NSAIDs), and relevant factors have been identified. Healthcare institutions should reinforce the management of rational drug use in the elderly to mitigate the occurrence of PIMs and pDDIs, thereby enhancing medication safety.

Spontaneous adverse drug reactions reported in a thirteen-year pharmacovigilance program in a tertiary university hospital

Objectives

We aimed to assess the characteristics of adverse drug reactions (ADRs) collected in a university hospital.

Methods

A retrospective analysis of ADRs spontaneously reported in the Hospital Pharmacovigilance Program database (RutiRAM) over a 13-year period was conducted. The analysis included a description of ADRs [System Organ Class (SOC)] and their seriousness, the drugs involved [level 1 of the Anatomical Therapeutic Chemical (ATC) Classification System], drug-drug interactions, medication errors, drugs 'under additional monitoring', positive rechallenge, and the 'pharmacovigilance interest' of ADRs. An ADR was considered of 'pharmacovigilance interest' when it was serious, and/or produced sequelae, and/or affected the paediatric population, and/or when the suspected drug was 'under additional monitoring'. Additionally, an exploratory analysis for bivariate associations through an automated method was performed.

Results

A total of 2,148 spontaneous ADRs were registered in the RutiRAM database, with 92.5% recorded by medical doctors. The mean age of cases was 59.2 years (SD 20.9), range 1 day-99 years; 5.7% were paediatric, 46.2% adults, and 48.1% elderly. The drugs most often involved were anti-infectives (ATC group J), mainly amoxicillin-clavulanic acid. 'Blood system disorders' were the most frequent SOC ADRs, and skin rashes were the most frequent ADRs. The 63.2% of ADRs were considered of 'pharmacovigilance interest'. Almost half of ADRs were hospital-acquired, and these were related to medication error; serious ADRs were related to drug-drug interactions and elderly patients, and involved drugs 'under additional monitoring' were related to younger ones.

Conclusion

This is the first study to overview of ADRs reported in an HPVP over more than a decade. Almost two-thirds of the ADRs collected in the RutiRAM database are of sufficient quality to be classified as 'pharmacovigilance interest', and thus can contribute to signal detection and the issuing of drug alerts by pharmacovigilance systems. Analysing ADRs in hospitals contributes to patient safety by implementing relevant actions to prevent medication errors or ADRs, some of which can be applied to other centres.

Impact of Vanessa's Law on the Reporting of Serious Adverse Events: A Retrospective Study Among Antiplatelet Users in a Tertiary-Care Cardiology Centre

Background

Antiplatelet drugs, such as clopidogrel, ticagrelor, prasugrel, and acetylsalicylic acid, may be associated with a risk of adverse events (AEs). Vanessa's Law was enacted to strengthen regulations to protect Canadians from drug-related side effects (with mandatory reporting of serious adverse events [SAEs]).

Objective

To determine whether Vanessa's Law has led to an increase in SAE reporting among antiplatelet users.

Methods

This descriptive retrospective study was conducted from January, 2018-December, 2021. Included are 260 adult antiplatelet users (cohorts: 2018 [n = 64]; 2019 [n = 79]; 2020 [n = 73]; 2021 [n = 44]) hospitalized at the Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval. The main diagnostic of hospitalization was coded using the International Classification of Diseases,10th revision, Canadian version, and data related to demographic characteristics, hospitalization length-of-stay, drugs administered, and AEs were extracted.

Results

The 260 antiplatelet users were hospitalized mainly for diseases of the circulatory system (codes [I00-I99]; 2018, 75 %; 2019, 71 %; 2020, 71 %; 2021, 77 %) or diseases of the respiratory system (codes [J00-J99]; 2018, 6 %; 2019, 8 %; 2020, 4 %; 2021, 7 %). The median age was 70 years. The median duration of hospital stay was 3 days. Among the 1395 AEs recorded during the study, 12 % were SAEs. None of the SAEs (or AEs) was reported to Health Canada, either before or after Vanessa's Law implementation.

Conclusions

These results provide the first picture of reporting trends for SAEs among antiplatelet users in Canada. Investigation of the underreporting of SAEs is needed, as the implementation of a mandatory policy does not seem to have had a favourable impact.

Clinical Trial Registration

135263.

Insight into Risk Factors, Pharmacogenetics/Genomics, and Management of Adverse Drug Reactions in Elderly: A Narrative Review

The European Medicine Agency (EMA) has defined Adverse Drug Reactions (ADRs) as "a noxious and unintended response to a medicine", not including poisoning, accidental, or intentional overdoses. The ADR occurrence differs based on the approach adopted for defining and detecting them, the characteristics of the population under study, and the research setting. ADRs have a significant impact on morbidity and mortality, particularly among older adults, and represent a financial burden for health services. Between 30% and 60% of ADRs might be predictable and preventable, emerging as a result of inappropriate prescription, drug chemistry inherent toxicity, cell-specific drug toxicity, age- and sex-related anomalies in drug absorption, distribution, metabolism, and elimination (ADME), and drug-drug interactions (DDIs) in combination therapies or when a patient is treated with different drugs for concomitant disorders. This is particularly important in chronic diseases which require long-term treatments. Rapid developments in pharmacogenetics/genomics have improved the understanding of ADRs accompanied by more accurate prescriptions and reduction in unnecessary costs. To alleviate the burden of ADRs, especially in the elderly, interventions focused on pharmaceutical principles, such as medication review and reconciliation, should be integrated into a broader assessment of patients' characteristics, needs, and health priorities. Digital health interventions could offer valuable solutions to assist healthcare professionals in identifying inappropriate prescriptions and promoting patient adherence to pharmacotherapies.

Adverse Drug Reactions and Potentially Inappropriate Medication in Older Patients: Analysis of the Portuguese Pharmacovigilance Database

Criteria have been developed to identify potentially inappropriate medications that can enhance adverse reactions, highly prevalent in older patient’s therapy. This study aimed to identify potentially inappropriate medications within the adverse drug reactions reported in the Portuguese pharmacovigilance system, characterizing the reports where inappropriate medications were identified. INFARMED, I.P. provided all adverse drug reactions reported from January to December 2019 in 65-year-old and older patients. Adverse drug reactions were characterized according to the System Organs Classes, seriousness, and medications with the Anatomical Therapeutical Classification. Potentially inappropriate medications were identified by applying the EU-(7)-PIM and the Beers criteria. A p value < 0.05 was considered statistically significant. From the 2337 reports considered for the analysis, PIMs were found in 12.8% of these, and 64.7% of all adverse reaction reports were classified as serious. Within the group of reports including at least one PIM, 71.4% were classified as serious, with hospitalization the most common criteria (35.1%). From the 3170 suspected medicines identified, 10.6% were classified as PIMs. Amiodarone was the most frequent PIM identified in the study (10.1%). Reports including at least one PIM were more associated with a higher number of ADRs (p = 0.025) reported in the same record, higher number of suspected medicines identified (p < 0.001), seriousness (p = 0.005), and hospitalization (p < 0.001). Potentially inappropriate medications are important enhancers of serious adverse drug reactions, increasing the likelihood of hospitalizations. This reinforces the importance of improving medication appropriateness in the older population.

Risk factors for adverse drug reactions associated with clopidogrel therapy

This study aimed to investigate the possible influence of genetic and non-genetic factors on the incidence of clopidogrel adverse drug reactions (ADRs) in cardiology patients, including the most important CYP2C19 alleles, namely *2 and *17, as well as compliance, dose, drug interactions, and clinical factors. A total of 102 clopidogrel-treated adult Caucasian patients hospitalized at the Cardiology Department of the Clinical Center of Montenegro were enrolled in the study. Data on clinical outcomes of interest were obtained by intensive monitoring ADRs during hospitalization and one year after hospital discharge. Genotyping for CYP2C19*2 and *17 was conducted using the real-time polymerase chain reaction method. ADRs were characterized using the Rawlins and Thompson classification and the World Health Organization criteria. Causality was assessed using the Naranjo probability scale. ADRs to clopidogrel were observed in 9 of 102 patients (8.8%). The observed frequencies of CYP2C19*2 and *17 were 13.2 and 25.5%, respectively. Our study, which is the first to report the frequency of CYP2C19 polymorphism in the Montenegrin population, as well as to link the pharmacovigilance of clopidogrel with CYP2C19 gene variability, shows that the incidence of ADRs of clopidogrel in cardiac patients is high and depends on CYP2C19 polymorphisms, comedication/drug interactions, and gastrointestinal comorbidity.

Safety of Non-Steroidal Anti-Inflammatory Drugs in the Elderly: An Analysis of Published Literature and Reports Sent to the Portuguese Pharmacovigilance System

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most frequently used agents to treat musculoskeletal disorders (principally by the elderly), thus raising the risk of adverse drug reactions (ADRs). This work aims to monitor NSAIDs safety profile in older people by using literature and pharmacovigilance data. Published clinical studies reporting the NSAIDs safety in elderly patients (age ≥ 65) were identified by a literature search and were then deeply analyzed. In addition, suspected ADRs reports submitted to the Portuguese Pharmacovigilance System (PPS) involving patients aged ≥65 with at least one NSAID as suspected drug were explored in detail. Most studies concluded that the risk of gastrointestinal, cardiovascular, and renal ADRs was significantly lower with cyclooxygenase-2 (COX-2)-selective NSAIDs use than with nonselective NSAIDs. The PPS data analysis showed that serious gastrointestinal ADRs occurred mostly in patients taking more than one NSAID and/or another concomitant drug that increases the incidence of these events, in the absence of gastroprotection. The results suggest that while NSAID toxicity is well understood, their safe use needs to be monitored in clinical practice. Furthermore, the pharmacovigilance data analyzed also showed that monitoring NSAIDs use in elderly remains essential to mitigate the associated risks, especially in those with comorbidities and under polytherapy.

ADENet: a novel network-based inference method for prediction of drug adverse events

Identification of adverse drug events (ADEs) is crucial to reduce human health risks and improve drug safety assessment. With an increasing number of biological and medical data, computational methods such as network-based methods were proposed for ADE prediction with high efficiency and low cost. However, previous network-based methods rely on the topological information of known drug-ADE networks, and hence cannot make predictions for novel compounds without any known ADE. In this study, we introduced chemical substructures to bridge the gap between the drug-ADE network and novel compounds, and developed a novel network-based method named ADENet, which can predict potential ADEs for not only drugs within the drug-ADE network, but also novel compounds outside the network. To show the performance of ADENet, we collected drug-ADE associations from a comprehensive database named MetaADEDB and constructed a series of network-based prediction models. These models obtained high area under the receiver operating characteristic curve values ranging from 0.871 to 0.947 in 10-fold cross-validation. The best model further showed high performance in external validation, which outperformed a previous network-based and a recent deep learning-based method. Using several approved drugs as case studies, we found that 32-54% of the predicted ADEs can be validated by the literature, indicating the practical value of ADENet. Moreover, ADENet is freely available at our web server named NetInfer (http://lmmd.ecust.edu.cn/netinfer). In summary, our method would provide a promising tool for ADE prediction and drug safety assessment in drug discovery and development.

Assessment of suspected adverse drug reactions in elderly patients with diabetes mellitus based on a Portuguese spontaneous reporting database: analysis of reporting from 2008 to 2018

BACKGROUND

Age is one of the most important risk factors in the development of diabetes mellitus and certain drug classes indicated for this condition may be associated with clinically important adverse drug reactions (ADRs). The aim of this study was to analyze the suspected ADRs in older patients with diabetes mellitus, reported to the Portuguese Pharmacovigilance System from 2008 to 2018.

RESEARCH DESIGN AND METHODS

A retrospective analysis of suspected ADRs reports was performed, involving patients aged ≥65 years.

RESULTS

Of a total of 751 reports collected, 439 were considered serious, 199 led to hospitalization and in 19 of them occurred a fatal outcome. Most of them were observed in females (n = 393) and involved patients belonging mainly to the age group 65-74 years (n = 405). Taking into account a total of 2134 suspected ADRs, the most frequent were hypoglycemia (2.67%) and lactic acidosis (2.62%). The drugs specifically indicated for glycemic control were the most frequently involved in ADRs.

CONCLUSIONS

Most of the ADRs were reported as serious and were mainly associated to drugs in diabetes mellitus. In addition, the majority of them, such as hypoglycemia, are preventable, highlighting the importance to identify possible factors that determine this occurrence, especially in the elderly.

Headache as an Adverse Reaction to the Use of Medication in the Elderly: A Pharmacovigilance Study

There is a consensus that elderly individuals are quite vulnerable to adverse drug reactions (ADRs), and headaches are one of the most frequent clinical presentations of central nervous system problems in the general population, which can be an ADR. The purpose of our work was to analyze reports of "headache" associated ADRs in the elderly sent to the Portuguese Pharmacovigilance System (PPS), and also which drugs were more frequently associated with this adverse reaction. A retrospective analysis of suspected ADR reports involving patients aged 65 years or older received by the PPS in the last 10 years was conducted. A search of all the terms associated with the High Level Term "headache" was performed. All duplicate reports were excluded from the analysis. A total of 155 ADRs reports were included, in which 15 reported isolated "headache" as suspected ADR, while the remaining 140 ADRs reports reported "headache" together with several other adverse reactions. Most reports of "headache" ADR occurred in women (74.8%; n = 116). About half (46.5%; n = 72) of the ADR reports were considered serious. Anti-viral medication, anti-depressants, anti-dyslipidemic agents and central nervous system-acting analgesics were the most frequent drugs associated with "headache" ADR reports in this population. In elderly patients, most ADR reports involving headaches occurred in women and a high percentage (46.5%) were considered serious. Thus, it is important that healthcare professionals pay more attention to headaches reported as ADRs in the elderly and drugs suspected to cause them, in order to increase knowledge about this type of reaction and contribute towards safely using drugs in this age group.