Adverse drug reactions causing hospital admissions in childhood: a prospective, observational, single-centre study

The epidemiology of drug-related hospital admissions in paediatrics - a systematic review

BACKGROUND

Despite previous efforts, medication safety in paediatrics remains a major concern. To inform improvement strategies and further research especially in outpatient care, we systematically reviewed the literature on the frequency and nature of drug-related hospital admissions in children.

METHODS

Searches covered Embase, Medline, Web of Science, grey literature sources and relevant article citations. Studies reporting epidemiological data on paediatric drug-related hospital admissions published between 01/2000 and 01/2024 were eligible. Study identification, data extraction, and critical appraisal were conducted independently in duplicate using templates based on the 'Joanna Briggs Institute' recommendations.

RESULTS

The review included data from 45 studies reporting > 24,000 hospitalisations for adverse drug events (ADEs) or adverse drug reactions (ADRs). Due to different reference groups, a total of 52 relative frequency values were provided. We stratified these results by study characteristics. As a percentage of inpatients, the highest frequency of drug-related hospitalisation was found with 'intensive ADE monitoring', ranging from 3.1% to 5.8% (5 values), whereas with 'routine ADE monitoring', it ranged from 0.2% to 1.0% (3 values). The relative frequencies of 'ADR-related hospitalisations' ranged from 0.2% to 6.9% for 'intensive monitoring' (23 values) and from 0.04% to 3.8% for 'routine monitoring' (8 values). Per emergency department visits, five relative frequency values ranged from 0.1% to 3.8% in studies with 'intensive ADE monitoring', while all other eight values were ≤ 0.1%. Heterogeneity prevented pooled estimates. Studies rarely reported on the nature of the problems, or studies with broader objectives lacked disaggregated data. Limited data indicated that one in three (median) drug-related admissions could have been prevented, especially by more attentive prescribing. Besides polypharmacy and oncological therapy, no other risk factors could be clearly identified. Insufficient information and a high risk of bias, especially in retrospective and routine observational studies, hampered the assessment.

CONCLUSION

Given the high frequency of drug-related hospitalisations, medication safety in paediatrics needs to be further improved. As routine identification appears unreliable, clinical awareness needs to be raised. To gain more profound insights especially for generating improvement strategies, we have to address under-reporting and methodological issues in future research.

TRIAL REGISTRATION

PROSPERO (CRD42021296986).

Changing patterns in the epidemiology of drug allergy

Drug allergy (DA) remains a complex and unaddressed problem worldwide that often deprives patients of optimal medication choices and places them at risk for life-threatening reactions. Underdiagnosis and overdiagnosis are common and due to the lack of standardized definitions and biomarkers. The true burden of DA is unknown, and recent efforts in data gathering through electronic medical records are starting to provide emerging patterns around the world. Ten percent of the general population engaged in health care claim to have a DA, and the most common label is penicillin allergy. Up to 20% of emergency room visits for anaphylaxis are due to DA and 15%-20% of hospitalized patients report DA. It is estimated that DA will increase based on the availability and use of new and targeted antibiotics, vaccines, chemotherapies, biologicals, and small molecules, which are aimed at improving patient's options and quality of life. Global and regional variations in the prevalence of diseases such as human immunodeficiency virus and mycobacterial diseases, and the drugs used to treat these infections have an impact on DA. The aim of this review is to provide an update on the global impact of DA by presenting emerging data on drug epidemiology in adult and pediatric populations.

Development and Adjustment of an Algorithm for Identifying Drug-Related Hospital Admissions in Pediatrics

OBJECTIVE

Adverse drug events (ADEs) in the outpatient pediatric pharmacotherapy can be serious and lead to inpatient admissions. Recent research only focused on ADE identification during hospitalization. The aim of the present study was to develop an algorithm to identify drug-related hospital admissions in pediatrics.

METHODS

A systematic literature research was performed, and a pediatric trigger tool for identifying drug-related inpatient admissions was built. The initial version was tested in a sample of 292 patients admitted to a German university children's hospital. Subsequently, the tool was further improved by combining different modules as a novel approach.

RESULTS

The obtained algorithm with 39 triggers in 5 modules identified drug-related inpatient admissions at a sensitivity of 95.5% (95% confidence interval [CI], 89.3%-100%) and a specificity of 16.5% (95% CI, 11.9%-21.2%), respectively. After modifications including trigger activation requiring a combination of different modules, specificity increased to 56.9% (95% CI, 50.7%-63.0%). Identifying 36 of 44 ADEs leading to admission, sensitivity remained high (81.8% [95% CI, 70.4%-93.2%]). The overall positive predictive value was 25.2% (95% CI, 18.1%-32.3%).

CONCLUSIONS

The algorithm is the first trigger tool to identify ambulant acquired ADEs leading to hospital admission in pediatrics. However, the underlying patient sample is small.Using a larger population for refinement will allow further specifications and reduction in the total amount of triggers and thus signals.

Drug-Related Hospital Admissions via the Department of Emergency Medicine: A Cross-Sectional Study From the Czech Republic

Background: Drug-related hospital admissions (DRAs) represent a significant problem affecting all countries worldwide. This study aimed to determine the prevalence and preventability of DRAs, identify the most common medications involved in DRAs, the most common clinical manifestations of DRAs and describe the preventability aspects of DRAs.

Methods: This cross-sectional study examined unplanned hospital admissions to the University Hospital Hradec Králové via the department of emergency medicine in August–November 2018. Data were obtained from electronic medical records. The methodology of DRA identification was adapted from the OPERAM DRA adjudication guide.

Results: Out of 1252 hospital admissions, 195 DRAs have been identified (145 related to treatment safety, 50 related to treatment effectiveness). The prevalence of DRAs was 15.6% (95% CI 13.6–17.6). The most common medication classes involved in DRAs related to treatment safety were Antithrombotic agents, Antineoplastic agents, Diuretics, Corticosteroids for systemic use, and Beta blocking agents. The most common medication classes involved in DRAs related to treatment effectiveness included Diuretics, Antithrombotic agents, Drugs used in diabetes, Agents acting on the renin-angiotensin system, and Lipid modifying agents. Gastrointestinal disorders were the leading causes of DRAs related to treatment safety, while Cardiac disorders were the leading causes of DRAs related to treatment effectiveness. The potential preventability of DRAs was 51%. The highest share of potential preventability in medication classes repeatedly involved in DRAs related to treatment safety was observed for Anti-inflammatory and antirheumatic products, Psycholeptics, and Drugs used in diabetes. Potentially preventable DRAs related to treatment safety were most commonly associated with inappropriate drug selection, inappropriate monitoring, inappropriate dose selection, and inappropriate lifestyle measures. On the contrary, DRAs related to treatment effectiveness were more commonly associated with medication nonadherence.

Conclusion: It should be emphasized that in most DRAs, medications were only a contributory reason of hospital admissions and that benefits and risks have to be carefully balanced. It is highlighted by the finding that the same medication classes (Antithrombotic agents and Diuretics) were among the most common medication classes involved in DRAs related to treatment safety and simultaneously in DRAs related to treatment effectiveness. The study highlighted that apart from problems related to prescribing, problems related to monitoring and patient-related problems represent significant preventability aspects.

Adverse Drug Reactions in Pediatric Oncohematology: A Systematic Review

Introduction: Adverse drug reactions (ADR) are an important cause of morbidity and mortality in pediatric patients. Due to the disease severity and chemotherapy safety profile, oncologic patients are at higher risk of ADR. However, there is little evidence on pharmacovigilance studies evaluating drug safety in this specific population.

Methods: In order to assess the incidence and characteristics of ADR in pediatric patients with oncohematogical diseases and the methodology used in the studies, a systematic review was carried out using both free search and a combination of MeSH terms. Data extraction and critical appraisal were performed independently using a predefined form.

Results: Fourteen studies were included, of which eight were prospective and half focused in inpatients. Sample size and study duration varied widely. Different methods of ADR identification were detected, used alone or combined. Causality and severity were assessed frequently, whereas preventability was lacking in most studies. ADR incidence varied between 14.4 and 67% in inpatients, and 19.6–68.1% in admissions, mainly in the form of hematological, gastrointestinal and skin toxicity. Between 11 and 16.4% ADR were considered severe, and preventability ranged from 0 to 74.5%.

Conclusion: ADR in oncohematology pediatric patients are frequent. A high variability in study design and results has been found. The use of methodological standards and preventability assessment should be reinforced in order to allow results comparison between studies and centers, and to detected areas of improvement.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=96513, identifier CRD42018096513.

Model Based Evaluation of Hypersensitivity Adverse Drug Reactions to Antimicrobial Agents in Children

Drug use in children is-in most cases-supported by extrapolation of data generated from clinical trials in adult populations. This puts children at higher risk of developing adverse drug reactions (ADRs) due to "off-label" use of drugs and dosing issues. Major types of ADRs are drug hypersensitivity reactions, an idiosyncratic type of ADRs that are largely unpredictable and can cause high morbidity and mortality in a hard-to-identify specific population of patients. Lack of a complete understanding of the pathophysiology of DHRs and their unpredictive nature make them problematic in clinical practice and in drug development. In addition, ethical and legal obstacles hinder conducting large clinical trials in children, which in turn make children a "therapeutic orphan" where clear clinical guidelines are lacking, and practice is based largely on the personal experience of the clinician, hence making modeling desirable. This brief review summarizes the current knowledge of model-based evaluation of diagnosis and management of drug hypersensitivity reactions (DHRs) to antimicrobial drugs in the pediatric population. Ethical and legal aspects of drug research in children and the effect of different stages of child development and other factors on the risk of DHRs are discussed. The role of animal models, in vitro models and oral provocation test in management of DHRs are examined in the context of the current understanding of the pathophysiology of DHRs. Finally, recent changes in drug development legislations have been put forward to encourage drug developers to conduct trials in children clearly indicate the urgent need for evidence to support drug safety in children and for modeling to guide these clinical trials.

Hospital admissions to geriatric ward related to adverse drug events: a cross-sectional study from the Czech Republic

Background Geriatric patients represent a vulnerable population in terms of adverse drug events (ADEs). Objective The aims of this study were to determine the prevalence and preventability of hospital admissions to a geriatric ward related to ADEs, to identify medications involved in these ADEs and to describe potential preventability aspects of ADE-related admissions. Setting University Hospital Hradec Králové, Czech Republic. Methods This cross-sectional study evaluated acute hospital admissions to the geriatric ward of University Hospital Hradec Králové over a period of nine months (April-December 2017). Medication reviews were performed in order to identify ADE-related hospital admissions. Causality was assessed using the World Health Organization-Uppsala Monitoring Centre criteria. Modified Schumock-Thornton algorithm was used to assess the preventability of ADEs. Main outcome measure 9-month-prevalence of ADE-related hospital admissions. Results A total of 366 hospital admissions were included. The 9-month-prevalence of ADE-related hospital admissions was 11.75% [95% confidence interval 8.45-15.05]. Antithrombotic agents and diuretics represented the most common medication classes associated with ADEs (30.2% each). Electrolyte disturbances and gastrointestinal haemorrhages and ulcerations were the most frequently observed ADEs associated with hospital admission. Out of 43 ADE-related hospitalisations, 23 (53.5%) were considered potentially preventable. Conclusion The contribution of ADEs to hospital admission to the geriatric ward was not negligible. Our results also suggest that 53.5% of identified ADE-related admissions could be potentially prevented. This finding demonstrates just how important the research on the preventability of medication-related hospitalisations is. Further studies and implementations are still needed aiming to minimize the risk of medication-related harm.

Adverse Drug Reactions in Children: Pediatric Pharmacy and Drug Safety

An underappreciated problem in child health is the risk for adverse drug reactions (ADRs). While there is an impression that children are at a lower risk than adults for ADRs, in fact a number of factors germane to pediatric therapy place certain groups of children at a high risk for adverse events associated with therapy. Given the importance of drug safety, an understanding of a diagnostic classification for ADRs and of how to approach a possible ADR clinically are key skills for pediatric pharmacists. As drug therapy for children evolves, becomes more complex, and begins to use novel molecules and biologicals there will be an increasing need for pediatric pharmacists to be more involved in clinical care, education, and research specific to drug safety.

Confidence and accuracy in identification of adverse drug reactions reported by outpatients

Background Patient reporting of adverse drug reactions (ADRs) could supplement the existing reporting system and contribute to early detection of ADRs. The confidence in ADR identification and their attribution of ADRs were limited to outpatients. Objective To determine the type and frequency of ADRs reported by outpatients, to evaluate confidence and accuracy in ADR identification as well as contributing factors. Setting University hospital in northeastern Thailand Method Cross-sectional study using questionnaires distributed to 500 outpatients who claimed to have experienced an ADR. Confidence in identifying ADRs was measured by visual analogue score (VAS), while accuracy of reported ADRs was determined using Naranjo algorithm and WHO criteria. Main outcome measure Number and type of ADRs, confidence rating and accuracy category. Results In total, 390 outpatients completed the questionnaire (response rate = 78.0%). Rash (19.0%), nausea/vomiting (7.4%), and dizziness (5.8%) were the top three reported ADRs. Sixty-one percent of respondents rated their level of confidence in identifying ADRs as high (VAS 9.2 ± 0.95), which was associated with having underlying diseases (OR 1.93), low number of reported symptoms (OR 0.38) and severe ADRs (OR 1.33). Causality assessment was classified as true ADRs in 90.0% and 88.9% of cases, using Naranjo algorithm and WHO criteria, respectively. Respondents with low number of reported symptoms (OR 0.27) and high level of confidence had greater accuracy in ADR identification (OR 1.11). Conclusion The outpatients reported a high proportion of potential ADRs with high confidence and accuracy. Patient reporting of ADRs has potential to support the pharmacovigilance system.

Characterization of serious adverse drug reactions as cause of emergency department visit in children: a 5-years active pharmacovigilance study

Background

To describe frequency, preventability and seriousness of adverse drug reactions (ADRs) in children as cause of emergency department (ED) admission and to evaluate the association between specific factors and the reporting of ADRs.

Methods

A retrospective analysis based on reports of suspected ADRs collected between January 1st, 2012 and December 31st, 2016 in the ED of Meyer Children’s Hospital (Italy). Demographics, clinical status, suspected drugs, ADR description, and its degree of seriousness were collected. Logistic regression was used to estimate the reporting odds ratios (RORs) with 95% confidence intervals (CIs) of potential predictors of ADR seriousness.

Results

Within 5 years, we observed 834 ADRs (1100 drug-ADR pairs), of whom 239 were serious; of them, 224 led to hospitalization. Patients were mostly treated with one drug. Among patients treated with more than one drug, 78 ADRs presented a potential interaction. The most frequently reported ADRs involved gastrointestinal system. The most frequently reported medication class was antinfectives. Risk of serious ADR was significantly lower in children and infants compared to adolescents (ROR 0.41 [95% CI: 0.27–0.61] and 0.47 [0.32–0.71], respectively), and it was significantly increased in subjects exposed to more than one drug (ROR 1.87 [1.33–2.62] and 3.01 [2.07–4.37] for subjects exposed to 2 and 3 or more drugs, respectively). Gender, interactions and off-label drug use did not influence the risk of serious ADRs.

Conclusion

Active surveillance in pharmacovigilance might represent the best strategy to estimate and characterize the clinical burden of ADRs in children.

Electronic supplementary material

The online version of this article (10.1186/s40360-018-0207-4) contains supplementary material, which is available to authorized users.

Mortality among patients due to adverse drug reactions that lead to hospitalization: a meta-analysis

PURPOSE

The aim of this study was to estimate the prevalence of mortality among patients due to adverse drug reactions that lead to hospitalisation (fatal ADR_Ad), to explore the heterogeneity in its estimation through subgroup analysis of study characteristics, and to identify system-organ classes involved and causative drugs for fatal ADR_Ad.

METHODS

We identified prospective ADR_Ad-related studies via screening of the PubMed and Google Scholar databases with appropriate key terms. We estimated the prevalence of fatal ADR_Ad using a double arcsine method and explored heterogeneity using the following study characteristics: age groups, wards, study region, ADR definitions, ADR identification methods, study duration and sample size. We examined patterns of fatal ADR_Ad and causative drugs.

RESULTS

Among 312 full-text articles assessed, 49 studies satisfied the selection criteria and were included in the analysis. The mean prevalence of fatal ADR_Ad was 0.20% (95% CI: 0.13-0.27%; I² = 93%). The age groups and study wards were the important heterogeneity modifiers. The mean fatal ADR_Ad prevalence varied from 0.01% in paediatric patients to 0.44% in the elderly. Subgroup analysis showed a higher prevalence of fatal ADR_Ad in intensive care units, emergency departments, multispecialty wards and whole hospitals. Computer-based monitoring systems in combination with other methods detected higher mortality. Intracranial haemorrhage, renal failure and gastrointestinal bleeding accounted for more than 50% of fatal ADR_Adcases. Warfarin, aspirin, renin-angiotensin system (RAS) inhibitors and digoxin accounted for 60% of fatal ADR_Ad.

CONCLUSIONS

ADR_Ad is an important cause of mortality. Strategies targeting the safer use of warfarin, aspirin, RAS inhibitors and digoxin could reduce the large number of fatal ADR_Adcases.

Categorization and association analysis of risk factors for adverse drug events

PURPOSE

Adverse drug events (ADE) are among the leading causes of morbidity and hospitalization. This review analyzes risk factors for ADE, particularly their categorizations and association patterns, the prevalence, severity, and preventability of ADE, and method characteristics of reviewed studies.

METHODS

Literature search was conducted via PubMed, Science Direct, CINAHL, and MEDLINE. A review was conducted of research articles that reported original data about specific risk factors for ADE since 2000. Data analyses were performed using Excel and R.

RESULTS

We summarized 211 risk factors for ADE, and grouped them into five main categories: patient-, disease-, medication-, health service-, and genetics-related. Among them, medication- and disease-related risk factors were most frequently studied. We further classified risk factors within each main category into subtypes. Among them, polypharmacy, age, gender, central nervous system agents, comorbidity, service utilization, inappropriate use/change use of drugs, cardiovascular agents, and anti-infectives were most studied subtypes. An association analysis of risk factors uncovered many interesting patterns. The median prevalence, preventability, and severity rate of reported ADE was 19.5% (0.29%~86.2%), 36.2% (2.63%~91%), and 16% (0.01%~47.4%), respectively.

CONCLUSIONS

This review introduced new categories and subtypes of risk factors for ADE. The broad and in-depth coverage of risk factors and their association patterns elucidate the complexity of risk factor analysis. Managing risk factors for ADE is crucial for improving patient safety, particularly for the elderly, comorbid, and polypharmacy patients. Some under-explored risk factors such as genetics, mental health and wellness, education, lifestyle, and physical environment invite future research.

Interrater agreement of two adverse drug reaction causality assessment methods: A randomised comparison of the Liverpool Adverse Drug Reaction Causality Assessment Tool and the World Health Organization-Uppsala Monitoring Centre system

Introduction

A new method to assess causality of suspected adverse drug reactions, the Liverpool Adverse Drug Reaction Causality Assessment Tool (LCAT), showed high interrater agreement when used by its developers. Our aim was to compare the interrater agreement achieved by LCAT to that achieved by another causality assessment method, the World Health Organization-Uppsala Monitoring Centre system for standardised case causality assessment (WHO-UMC system), in our setting.

Methods

Four raters independently assessed adverse drug reaction causality of 48 drug-event pairs, identified during a hospital-based survey. A randomised design ensured that no washout period was required between assessments with the two methods. We compared the methods’ interrater agreement by calculating agreement proportions, kappa statistics, and the intraclass correlation coefficient. We identified potentially problematic questions in the LCAT by comparing raters’ responses to individual questions.

Results

Overall unweighted kappa was 0.61 (95% CI 0.43 to 0.80) on the WHO-UMC system and 0.27 (95% CI 0.074 to 0.46) on the LCAT. Pairwise unweighted Cohen kappa ranged from 0.33 to 1.0 on the WHO-UMC system and from 0.094 to 0.71 on the LCAT. The intraclass correlation coefficient was 0.86 (95% CI 0.74 to 0.92) on the WHO-UMC system and 0.61 (95% CI 0.39 to 0.77) on the LCAT. Two LCAT questions were identified as significant points of disagreement.

Discussion

We were unable to replicate the high interrater agreement achieved by the LCAT developers and instead found its interrater agreement to be lower than that achieved when using the WHO-UMC system. We identified potential reasons for this and recommend priority areas for improving the LCAT.

An assessment of reported adverse drug reactions in a Tertiary Care Hospital in South India: A retrospective cross-sectional study

Objective:

The primary objective of this study was to assess the causality of ADRs using World Health Organization-Uppsala Monitoring Centre (WHO–UMC), Naranjo and Liverpool ADR Causality Assessment Tool (LCAT). Other primary objective was to assess the agreement between the WHO-UMC criterion, Naranjo algorithm and LCAT. The secondary objective was to assess the reported adverse drug reactions in a tertiary care hospital in South India.

Materials and Methods:

This was a cross-sectional retrospective study. All the ADRs which were reported by the Pharmacovigilance Unit between July 2016 and March 2017 were assessed. Causality assessment was performed by two well-trained independent pharmacologists by applying the three methods–WHO, Naranjo and LCAT. Concurrence between the two algorithms was compared using the Cohen's weighted kappa statistic.

Results:

Causality assessment of adverse reactions according to Naranjo criteria shows that 81% cases were of probable type, 9.5% cases were possible and 9.5% cases were unlikely. Causality assessment of adverse reactions according to WHO-UMC criteria shows that 85.7% cases were of probable type, 4.8% cases were possible, 4.8% cases were unlikely and 4.8% cases were definite. Causality assessment of adverse reactions according to Liverpool criteria shows that 61.9% cases were of probable type, 4.8% cases were possible and 33.3% cases were definite. Cohen's kappa test shows that negative and poor concurrence was seen between WHO and Naranjo causality comparison (κ = −0.161). Positive but poor concurrence based on kappa values was seen between Liverpool and Naranjo's causality comparison (κ = 0.133). Negative and poor concurrence based on kappa values was seen between WHO and Liverpool causality comparison (κ = −0.161).

Conclusion:

The most frequent causality category observed by the WHO-UMC criteria, Naranjo as well as the Liverpool algorithm was “Probable.” Full concurrence was not found between any of two scales of causality assessment.