Lack of awareness of community-acquired adverse drug reactions upon hospital admission : dimensions and consequences of a dilemma

A prospective intervention study to identify drug-related emergency department visits comparing a standard care group and a pharmaceutical care group

BACKGROUND AND IMPORTANCE

Adverse drug reactions impose a major burden. Those adverse drug reactions might lead to hospitalization but are often not correctly identified in the emergency department (ED). Clinical pharmacists, although not routinely implemented, can help identify adverse drug reactions.

OBJECTIVE

The primary objective was to examine the drug association of ED visits in a pharmaceutical group with a clinical pharmacist integrated in the ED team compared with a standard group without additional support.

DESIGN/SETTING/PARTICIPANTS

This prospective intervention study was performed in the ED of a tertiary care university hospital in Leipzig, Germany. Patients who were ≥50 years old were included. From 1 March 2020 to May 31, 2020 patients were enrolled in the standard group. From 1 March 2021 to 31 May 2021, the pharmaceutical group was enrolled. The clinical pharmacist supported the ED team with patient´s detailed medication history and medication analysis. In both groups, patients were evaluated whether their ED visit was drug-related.

OUTCOME MEASURES AND ANALYSIS

The number of identified drug-related ED presentations were compared between the two groups. Interventions performed on adverse drug reaction management, causative drugs and patient characteristics were evaluated.

MAIN RESULTS

A total of 798 patients were enrolled in the standard group and 827 patients in the pharmaceutical group. Patients whose ED visit was drug-related had a median age of 77 years [(Q25-Q75) 63.5-83.5] and took 7 [(Q25-Q75) 5-8] drugs in standard group. In the pharmaceutical group median age was 78 years [(Q25-Q75) 66-83] and number of drugs taken was 9 [(Q25-Q75) 5.25-11]. 31 (3.9%) drug-related ED visits were identified in the standard group compared to 104 (12.6%) in the pharmaceutical group (OR 3.56; 95% CI 2.35-5.38). An intervention on the patient's pharmacotherapy was performed in 16 drug-related ED visits in standard group compared to 77 in the pharmaceutical group.

CONCLUSION

In this study the implementation of a clinical pharmacist was associated with improved identification of drug-related ED visits. Discontinuations of causal medications and dose reductions were significantly higher in the pharmaceutical group compared to the standard care group.

[Adverse drug reactions as cause of nonspecific symptoms in patients in the emergency department]

BACKGROUND

In a large proportion of patients admitted to the emergency department (ED), the initial main symptom is nonspecific. One possible reason for this, especially in older patients, may be adverse drug reactions (ADR) due to their frequent polypharmacy.

AIM

To illustrate the incidence of ADRs, the affected patient population including risk factors, and drug classes with ADRs leading to nonspecific symptoms. To provide practice recommendations for the management of ADRs in the ED.

MATERIAL AND METHODS

Presentation of the pharmacological principles on ADRs, statistics of pharmacovigilance centers as well as original literature including experiences from clinical practice and own projects.

RESULTS

In 10% of patients with nonspecific symptoms an ADR is responsible for presentation in the ED. In 60% of cases these ADRs are not correctly identified in the ED setting. A small number of drug classes are responsible for most of these referrals. Databases, risk stratification, clinical pharmacists, or clinical decision support systems are available to improve ADR identification and management. As these options are partly associated with considerable costs or the validation for German EDs is missing, a widespread application does not take place.

CONCLUSION

Correct identification of ADRs in patients with nonspecific symptoms in the ED is necessary to initiate adequate treatment. These ADRs are often overlooked because processes and tools for identification and management are not applied in the ED, leading to a lack of awareness. For high-risk patients in the ED, the focus should be on drug history, ideally considering patient-specific risk factors and specific drug classes.

Epidemiological investigation of emergency infusion adverse drug reactions in Nanjing, China: a prospective cross-sectional study

OBJECTIVE

Little is known about the morbidity and mortality of infusion Adverse drug reactions (ADRs) in the emergency department. We sought to evaluate the epidemiology of emergency infusion ADRs.

MATERIALS AND METHODS

This was a prospective study of infusion ADRs in the emergency infusion unit (EIU) of a tertiary hospital from 1 January 20201 January 2020, to 31 December 2021w31 December 2021. Emergency infusion ADRs were identified as intravenous drug-related ADRs that the causality was determined using the Naranjo algorithm. The incidence, severity and preventability of these ADRs were assessed using other standard criteria.

RESULTS

A total of 327 ADRs were recorded for 320 participants, antibiotics were the class of drugs most commonly involved, and 76.15% of ADRs occurred within the first hour. The most common symptoms observed were skin manifestations, accounting for 46.04% of ADRs. Mild reactions accounted for 85.32% based on the Hartwig and Siegel scale. In 89.30% of the reports, the ADRs were evaluated as not preventable based on the modified Schumock and Thornton scale. The causality and severity of ADRs were related to Charlson Comorbidity Index score and age (P < 0.05).

CONCLUSION

This epidemiological study described the pattern of emergency infusion ADRs in East China in detail. These findings may be useful to compare patterns among different centers.

An inter-professional student-run medication review programme. Reducing adverse drug reactions in a memory outpatient clinic: a controlled clinical trial

BACKGROUND

We investigated if the addition of an inter-professional student-led medication review team (ISP-team) to standard care can increase the number of detected ADRs and reduce the number of ADRs 3 months after an outpatient visit.

RESEARCH DESIGN AND METHODS

In this controlled clinical trial, patients were allocated to standard care (control group) or standard care plus the ISP team (intervention group). The ISP team consisted of medical and pharmacy students and student nurse practitioners. The team performed a structured medication review and adjusted medication to reduce the number of ADRs. Three months after the outpatient visit, a clinical pharmacologist who was blinded for allocation performed a follow-up telephone interview to determine whether patients experienced ADRs.

RESULTS

During the outpatient clinic visit, significantly more (p < 0.001) ADRs were detected in the intervention group (n = 48) than in the control group (n = 10). In both groups, 60-63% of all detected ADRs were managed. Three months after the outpatient visit, significantly fewer (predominantly mild and moderately severe) ADRs related to benzodiazepine derivatives and antihypertensive causing dizziness were detected in the patients of the intervention group.

CONCLUSIONS

An ISP team in addition to standard care increases the detection and management of ADRs in elderly patients resulting in fewer mild and moderately severe ADRs.

Exploring the prevalence and characteristics of adverse drug events among older adults in South Korea using a national health insurance database

Background: Adverse drug events (ADEs) in the elderly frequently occur because of their multiple chronic diseases and complexity of drug therapy. To better understand adverse drug events, the prevalence and characteristics of adverse drug events in elderly South Korean patients were assessed.

Methods: The National Health Insurance databases for 2015 and 2016 were used for the analysis. We included patients aged ≥65 years that had at least one claim with the diagnosis codes ‘drug-induced,’ ‘poisoning by drug,’ and ‘vaccine-associated’ each year for the base-case analysis. To minimize the underestimation of adverse drug event prevalence, we also used an extended definition analysis by adding the ‘adverse drug event very likely’ codes. We estimated the prevalence of adverse drug events by sex, age group, and type of insurance and examined the frequent types of adverse drug events in 2015 and 2016.

Results: In the base-case analysis, adverse drug event prevalence in individuals aged 65 years and older was 2.75% in 2015 and 2.77% in 2016. With advanced age, the prevalence of adverse drug event tended to increase, peaking in the age group of 75–79 years. In addition, the adverse drug event prevalence was higher in females and Medical Aid enrollees. The most frequently occurring adverse drug event was ‘allergy, unspecified,’ followed by ‘other drug-induced secondary parkinsonism,’ and ‘generalized skin eruption due to drugs and medicaments.’ When we examined the extended definition analysis, the prevalence of adverse drug events was 4.47% in 2015 and 4.52% in 2016, which significantly increased from those estimated in the base-case analysis.

Conclusion: Among the older adults, the prevalence of adverse drug event was higher in advanced age, females, and Medical Aid enrollees. In particular, allergy and drug-induced secondary parkinsonism frequently occurred. This study provides evidence that health policies addressing the prevention and management of adverse drug events should be a priority for the most vulnerable elderly patients.

Ali S, Ting KN, Boardman H. Pharmacists’ experiences on adverse drug reaction: 10 years later

Adverse drug reaction (ADR) is one of the leading public health concerns associated with high mortality rate. Healthcare professionals, particularly pharmacists, have a significant role in monitoring and preventing ADRs. This study was conducted on Malaysian Pharmaceutical Society (MPS) pharmacists who worked at the hospitals, health clinics, and community pharmacies to determine if pharmacists’ experiences on ADRs are still the same 10 years later. In 2010, a postal survey and in 2020, an online survey were conducted among these pharmacists. A total of 472 pharmacists and 208 participated in 2010 and 2020, respectively. About 82% and 90% of hospital/health clinic pharmacists (HCPs) observed an ADR over the last 6 months in 2010 and 2020, while 60% and 100% community pharmacists in 2010 and 2020 observed an ADR, respectively. Perindopril was the top drug (HCPs: p = 0.657; CPs: p = 0.98), and rash was the top ADR reported by the pharmacists in both years (HCPs: p &lt; 0.001; CPs: p = 0.679). The most common actions taken by HCPs in 2010 were to report the ADR (p = 0.343), while in 2020, most HCPs explained to patients regarding the reaction (p = 0.061), which was also the same in the CP group in 2020 (p = 0.958). The top factor encouraging ADR reporting in both years and both pharmacist groups was the high degree of severity of the reaction (HCPs: p &lt; 0.001; CPs: p = 0.769). While the top factors discouraging ADR reporting were a lack of information from the affected patients (HCPs: p = 0.2; CPs: p = 0.656), reaction is widely known (HCPs: p = 0.001; CPs: p = 0.144) and uncertainty of the causal relationship (HCPs: p = 0.169; CPs: p = 0.609). Majority of the pharmacists agreed that severe reactions should be reported (HCPs: p = 0.158; CPs: p = 0.501) and the main aim for reporting is to measure the incidence of ADRs (HCPs: p = 0.148; CPs: p = 0.762). Despite being able to identify ADRs during the daily practice, many pharmacists especially community pharmacists are not reporting them. There is a misconception on the purpose of reporting ADRs. An interventional program and ADR reporting training would be a useful step in improving ADR reporting practice.

Adverse drug events leading to emergency department visits: A multicenter observational study in Korea

Adverse drug events are significant causes of emergency department visits. Systematic evaluation of adverse drug events leading to emergency department visits by age is lacking. This multicenter retrospective observational study evaluated the prevalence and features of adverse drug event-related emergency department visits across ages. We reviewed emergency department medical records obtained from three university hospitals between July 2014 and December 2014. The proportion of adverse drug events among total emergency department visits was calculated. The cause, severity, preventability, and causative drug(s) of each adverse drug event were analyzed and compared between age groups (children/adolescents [<18 years], adults [18–64 years], and the elderly [≥65 years]). Of 59,428 emergency department visits, 2,104 (3.5%) were adverse drug event-related. Adverse drug event-related emergency department visits were more likely to be female and older. Multivariate logistic regression analysis revealed that compared to non- adverse drug event-related cases, adverse drug event-related emergency department visitors were more likely to be female (60.6% vs. 53.6%, p<0.001, OR 1.285, 95% CI 1.025–1.603) and older (50.8 ± 24.6 years vs. 37.7 ± 24.4 years, p<0.001, OR 1.892, 95% CI: 1.397–2.297). Comorbidities such as diabetes, chronic kidney disease, chronic liver disease, and malignancies were also significantly associated with adverse drug event-related emergency department visits. Side effects were the most common type of adverse drug events across age groups, although main types differed substantially depending on age. Serious adverse drug events, hospitalizations, and adverse drug event-related deaths occurred more frequently in the elderly than in adults or children/adolescents. The proportion of adverse drug event-related emergency department visits that were preventable was 15.3%. Causative drugs of adverse drug events varied considerably depending on age group. Adverse drug event features differ substantially according to age group. The findings suggest that an age-specific approach should be adopted in the preventive strategies to reduce adverse drug events.

Medical students as adverse drug event managers, learning about side effects while improving their reporting in clinical practice

Managing adverse drug reactions (ADRs) is a challenge, especially because most healthcare professionals are insufficiently trained for this task. Since context-based clinical pharmacovigilance training has proven effective, we assessed the feasibility and effect of a creating a team of Junior-Adverse Drug Event Managers (J-ADEMs). The J-ADEM team consisted of medical students (1st-6th year) tasked with managing and reporting ADRs in hospitalized patients. Feasibility was evaluated using questionnaires. Student competence in reporting ADRs was evaluated using a case-control design and questionnaires before and after J-ADEM program participation. From Augustus 2018 to Augustus 2019, 41 students participated in a J-ADEM team and screened 136 patients and submitted 65 ADRs reports to the Netherlands Pharmacovigilance Center Lareb. Almost all patients (n = 61) found it important that "their" ADR was reported, and all (n = 62) patients felt they were taken seriously by the J-ADEM team. Although attending physicians agreed that the ADRs should have been reported, they did not do so themselves mainly because of a "lack of knowledge and attitudes" (50%) and "excuses made by healthcare professionals" (49%). J-ADEM team students were significantly more competent than control students in managing ADRs and correctly applying all steps for diagnosing ADRs (control group 38.5% vs. intervention group 83.3%, p < 0.001). The J-ADEM team is a feasible approach for detecting and managing ADRs in hospital. Patients were satisfied with the care provided, physicians were supported in their ADR reporting obligations, and students acquired relevant basic and clinical pharmacovigilance skills and knowledge, making it a win-win-win intervention.

Medical students as junior adverse drug event managers facilitating reporting of ADRs

The Junior Adverse Drug Event Manager (J-ADEM) team is a multifaceted intervention focusing on real-life education for medical students that has been shown to assist healthcare professionals in managing and reporting suspected adverse drug reactions (ADRs) to the Netherlands Pharmacovigilance Centre Lareb. The aim of this study was to quantify and describe the ADRs reported by the J-ADEM team and to determine the clinical potential of this approach. The J-ADEM team consisted of medical students tasked with managing and reporting ADRs in hospitalized patients. All ADRs screened and reported by J-ADEM team were recorded anonymously, and categorized and analysed descriptively. From August 2018 through January 2020, 209 patients on two wards in an academic hospital were screened for ADR events. The J-ADEM team reported 101 ADRs. Although most ADRs (67%) were first identified by healthcare professionals and then reported by the J-ADEM team, the team also reported an additional 33 not previously identified serious ADRs. In 10% of all reported ADRs, the J-ADEM team helped optimize ADR treatment. The ADR reports were largely well-documented (78%), and ADRs were classified as type A (66%), had a moderate or severe severity (85%) and were predominantly avoidable reactions (69%). This study shows that medical students are able to screen patients for ADRs, can identify previously undetected ADRs and can help optimize ADR management. They significantly increased (by 300%) the number of ADR reports submitted, showing that the J-ADEM team can make a valuable clinical contribution to hospital care.

Detection of adverse drug events in e-prescribing and administrative health data: a validation study

BACKGROUND

Administrative health data are increasingly used to detect adverse drug events (ADEs). However, the few studies evaluating diagnostic codes for ADE detection demonstrated low sensitivity, likely due to narrow code sets, physician under-recognition of ADEs, and underreporting in administrative data. The objective of this study was to determine if combining an expanded ICD code set in administrative data with e-prescribing data improves ADE detection.

METHODS

We conducted a prospective cohort study among patients newly prescribed antidepressant or antihypertensive medication in primary care and followed for 2 months. Gold standard ADEs were defined as patient-reported symptoms adjudicated as medication-related by a clinical expert. Potential ADEs in administrative data were defined as physician, ED, or hospital visits during follow-up for known adverse effects of the study medication, as identified by ICD codes. Potential ADEs in e-prescribing data were defined as study drug discontinuations or dose changes made during follow-up for safety or effectiveness reasons.

RESULTS

Of 688 study participants, 445 (64.7%) were female and mean age was 64.2 (SD 13.9). The study drug for 386 (56.1%) patients was an antihypertensive, and for 302 (43.9%) an antidepressant. Using the gold standard definition, 114 (16.6%) patients experienced an ADE, with 40 (10.4%) among antihypertensive users and 74 (24.5%) among antidepressant users. The sensitivity of the expanded ICD code set was 7.0%, of e-prescribing data 9.7%, and of the two combined 14.0%. Specificities were high (86.0-95.0%). The sensitivity of the combined approach increased to 25.8% when analysis was restricted to the 27% of patients who indicated having reported symptoms to a physician.

CONCLUSION

Combining an expanded diagnostic code set with e-prescribing data improves ADE detection. As few patients report symptoms to their physician, higher detection rates may be achieved by collecting patient-reported outcomes via emerging digital technologies such as patient portals and mHealth applications.

[Efficacy of decision support systems to improve medication safety - results of the evaluation of the "Arzneimittelkonto NRW"]

Polypharmacy increases the risk of adverse drug reactions, especially in the elderly. Therefore, the reduction of potentially inadequate medication (PIM), an improvement in drug therapy safety and, in general, a more rational use of drugs is an objective of various interventions. The aim of this prospective single-arm interventional study is to investigate the potential of a decision support system (DSS; "Arzneimittelkonto NRW") to improve medication safety in outpatient care. 15 primary care physicians participating in the study recruited 874 patients. Prescription data and results of medication safety tests were available for 654 patients. Data of at least 12 months were available for 86% of these patients. PIM prevalence declined within 12 months (-11.3%), but not at a statistically significant level. The number of prescriptions after the introduction of the DSS is significantly below the prescription volume before the introduction of the DSS (-14.1%). Constantly high alteration rates of up to 85% were observed, for example, on drug interaction system warnings made by the DSS. Technical decision support systems have the potential to support a safer and cost-saving drug use. For the first time, this pilot study provides evidence for this in the context of standard outpatient care in Germany. However, further investigations are necessary to establish a robust body of evidence. A particular focus should be on the qualitative monitoring of the studies and the involvement of other actors in the care process.

Impact of the 2016 Policy Change on the Delivery of MedsCheck Services in Ontario: An Interrupted Time-Series Analysis

MedsCheck (MC) is an annual medication review service delivered by community pharmacists and funded by the government of Ontario since 2007 for residents taking three or more medications for chronic conditions. In 2010, MC was expanded to include patients with diabetes (MCD), home-bound patients (MCH), and residents of long-term care homes (MCLTC). The Ontario government introduced an abrupt policy change effective 1 October 2016 that added several components to all MC services, especially those completed in the community. We used an interrupted time series design to examine the impact of the policy change (24 months pre- and post-intervention) on the monthly number of MedsCheck services delivered. Immediate declines in all services were identified, especially in the community (47%–64% drop MC, 71%–83% drop MCD, 55% drop MCH, and 9%–14% drop MCLTC). Gradual increases were seen over 24 months post-policy change, yet remained 21%–76% lower than predicted for MedsCheck services delivered in the community, especially for MCD. In contrast, MCLTC services were similar or exceeded predicted values by September 2018 (from 5.1% decrease to 3.5% increase). A more effective implementation of health policy changes is needed to ensure the feasibility and sustainability of professional community pharmacy services.

Adverse Drug Reactions (ADR) and Emergencies

BACKGROUND

Adverse drug reactions (ADR) are a common reason for emergency room visits and for hospitalization. An ADR is said to have occurred when the patient's symptoms and signs are considered to be possibly, probably, or definitely related to the intake of a drug.

METHODS

In four large hospital emergency departments, one in each of four German cities ( Ulm, Fürth, Bonn, and Stuttgart), the percentage of suspected ADR cases among all patients presenting to the emergency room was determined during a 30-day period of observation. ADRs were ascertained by screening the digital records of all patients seen in the emergency room; causality was assessed as specified by the WHO-UMC (Uppsala Monitoring Center).

RESULTS

ADR were sought in a total of 10 174 emergency department visits. 665 cases of suspected ADR were found, yielding a prevalence of 6.5%. The prevalence of ADR among patients with documented drug intake was 11.6%. Among the patients with documented suspected ADRs, 89% were hospitalized (in contrast to the 43.7% hospitalization rate in the entire group of 10 174 emergency department visits). A possible causal relationship between the patient's symptoms and signs and the intake of a drug was found in 74-84% of cases. Patients with ADR were found to be taking a median of 7 different drugs simultaneously.

CONCLUSION

Adverse drug reactions are a relevant cause of emergency department visits, accounting for 6.5% of the total visits in this study, and often lead to hospital admission. The ADRED (Adverse Drug Reactions in Emergency Departments) study, which is now being conducted, is intended to shed further light on their causes, patient risk factors, and potential avoidability.

Development of a mortality score to assess risk of adverse drug reactions among hospitalized patients with moderate to severe chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a significant health burden that increases the risk of adverse events. Currently, there is no validated models to predict risk of mortality among CKD patients experienced adverse drug reactions (ADRs) during hospitalization. This study aimed to develop a mortality risk prediction model among hospitalized CKD patients whom experienced ADRs.

METHODS

Patients data with CKD stages 3-5 admitted at various wards were included in the model development. The data collected included demographic characteristics, comorbid conditions, laboratory tests and types of medicines taken. Sequential series of logistic regression models using mortality as the dependent variable were developed. Bootstrapping method was used to evaluate the model's internal validation. Variables odd ratio (OR) of the best model were used to calculate the predictive capacity of the risk scores using the area under the curve (AUC).

RESULTS

The best prediction model included comorbidities heart disease, dyslipidaemia and electrolyte imbalance; psychotic agents; creatinine kinase; number of total medication use; and conservative management (Hosmer and Lemeshow test =0.643). Model performance was relatively modest (R square = 0.399) and AUC which determines the risk score's ability to predict mortality associated with ADRs was 0.789 (95% CI, 0.700-0.878). Creatinine kinase, followed by psychotic agents and electrolyte disorder, was most strongly associated with mortality after ADRs during hospitalization. This model correctly predicts 71.4% of all mortality pertaining to ADRs (sensitivity) and with specificity of 77.3%.

CONCLUSION

Mortality prediction model among hospitalized stages 3 to 5 CKD patients experienced ADR was developed in this study. This prediction model adds new knowledge to the healthcare system despite its modest performance coupled with its high sensitivity and specificity. This tool is clinically useful and effective in identifying potential CKD patients at high risk of ADR-related mortality during hospitalization using routinely performed clinical data.

Personal genome testing on physicians improves attitudes on pharmacogenomic approaches

In this era of clinical genomics, the accumulation of knowledge of pharmacogenomics (PGx) is rising dramatically and attempts to utilize it in clinical practice are also increasing. However, this advanced knowledge and information have not yet been sufficiently utilized in the clinical field due to various barriers including physician factors. This study was conducted to evaluate the attitudes of physicians to PGx services by providing them their own genomic data analysis report focusing on PGx. We also tried to evaluate the clinical applicability of whole exome sequencing (WES)-based functional PGx test. In total 88 physicians participated in the study from September 2015 to August 2016. Physicians who agreed to participate in the study were asked to complete a pre-test survey evaluating their knowledge of and attitude toward clinical genomics including PGx. Only those who completed the pre-test survey proceeded to WES and were provided with a personal PGx analysis report in an offline group meeting. Physicians who received these PGx reports were asked to complete a follow-up survey within two weeks. We then analyzed changes in their knowledge and attitude after reviewing their own PGx analysis results through differences in their pre-test and post-test survey responses. In total, 70 physicians (79.5%) completed the pre-test and post-test surveys and attended an off-line seminar to review their personal PGx reports. After physicians reviewed the report, their perception of and attitude towards the PGx domain and genomics significantly changed. Physician’ awareness of the likelihood of occurrence of adverse drug reactions and genetic contribution was also changed significantly. Overall, physicians were very positive about the value and potential of the PGx test but maintained a conservative stance on its actual clinical use. Results revealed that physicians’ perception and attitude to the utility of PGx testing was significantly changed after reviewing their own WES results.

Psychiatrists' and dentists' knowledge and attitudes regarding adverse drug reactions of psychotropic drugs

Psychotropic drugs may induce impairments in the mouth, jaw and face area. Currently, appropriate pharmacoepidemiologic data are missing. Therefore, a questionnaire-based telephone survey of two non-representative samples of psychiatrists and dentists was conducted. Most of the psychiatrists (79.7%) and dentists (76.5%) indicated that psychotropic drugs may induce dental adverse drug reactions (ADR); in both samples there was an approximately equally sized, relevant proportion of participants who did not believe in the risk of dental ADR of psychotropic drugs (psychiatrists 20.3%; dentists 23.5%). About one third of the participants of both samples (psychiatrists 34.9%; dentists 35.9%) felt that dental ADRs of psychotropic drugs are a serious health problem. The majority of both groups (psychiatrists 97.8%; dentists 97.0%) had never reported a dental ADR. Most psychiatrists and dentists appeared to be aware of the risk of dental ADRs by psychotropic drugs. A relevant proportion of participants of both groups considered psychotropic drugs to be irrelevant regarding dental ADRs; therefore, there may be information needs in both groups. The willingness to report dental ADRs of psychotropic drugs was low in both groups; the evaluation of the actual relevance of this drug-related risk is impeded by the absence of reports of suspected ADRs.

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 ADRAd), 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 ADRAd.

METHODS

We identified prospective ADRAd-related studies via screening of the PubMed and Google Scholar databases with appropriate key terms. We estimated the prevalence of fatal ADRAd 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 ADRAd 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 ADRAd 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 ADRAd prevalence varied from 0.01% in paediatric patients to 0.44% in the elderly. Subgroup analysis showed a higher prevalence of fatal ADRAd 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 ADRAdcases. Warfarin, aspirin, renin-angiotensin system (RAS) inhibitors and digoxin accounted for 60% of fatal ADRAd.

CONCLUSIONS

ADRAd 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 ADRAdcases.

Adverse drug events-Analysis of a decade. A Portuguese case-study, from 2004 to 2013 using hospital database

PURPOSE

The goal of this study was to characterise adverse drug events (ADE), including both adverse drug reaction (ADR) and accidental poisoning by drugs (AP), considering age, gender, length of stay (LOS), number of deaths and year, during the period 2004-2013. Additionally distributions of the ten's most frequent ADR and AP were characterized, considering age-group and gender.

METHODS

A retrospective descriptive nationwide study was conducted, based on the hospital discharges database in Portugal from 2004 to 2013, using ICD-9. Events were identified based on the following codes: from E930 to E949.9 and from E850 to E858.9.

RESULTS

A total of 9 320 076 patients were discharged within this period, with 133 688 patients (1.46%) having at least one ADE, 4% of them related with AP. The mean age of these patients was 63.79 years (SD 21.31), 54.50% were female and the mean LOS was 14.05 days (SD 22.19). Patient with AP had a mean age of 41.06 years (SD 34.05), 54.70% were female and LOS was 7.15 days (SD 19.42). We have identified 10.691 deaths that represent 8.00% from the total of patients with an ADE. The patients above 65 years were more affected by ADR and children below 18 were more affected by AP.

CONCLUSION

In the last decade an increasing trend of ADR were observed and an AP pattern relatively stable. Elderly people and children were the age groups most affected. Antibiotics (in ADR) and benzodiazepine-based tranquilizers (in AP) were the major problems. This is a huge, increasing and challenging problem. Further research, using individual and contextual risk factors should be developed to understand spatiotemporal variability, promoting tailored interventions, within and across countries.

Hospitalizations due to preventable adverse reactions-a systematic review

PURPOSE

The study aimed to measure the percentage of preventable adverse drug reactions that lead to the hospitalization (PADRAd) and to explore the heterogeneity in its estimation through subgroup analysis of study characteristics.

METHODS

Two investigators independently searched in electronic databases and related bibliography for prospective studies involving PADRAd. We excluded studies investigating medication errors and spontaneous and retrospective reporting. The primary outcome was PADRAd percentage. To explore the heterogeneity, we performed subgroup analysis based on study region, wards, age groups, adverse drug reaction (ADR) definitions, preventability assessment, ADR identification methods, study duration and sample size. We explored fatal PADRAd and causative drugs as a secondary outcome. We used the generic inverse variance method with random effect model to compute meta-analytic summary.

RESULTS

Of the 68 full-text articles assessed, we included 22 studies. The mean PADRAd percentage was 45.11 % (95 % CI = 33.06-57.15; I 2 = 99 %). Studies including elderly (63.31 %) and all age groups (49.03 %) showed higher percentages than paediatric population (16.40 %). Studies examining all hospital populations showed higher percentages than specific wards. We observed high percentages in studies using Edwards and Aronson as an ADR definition and Hallas et al. as a preventability assessment tool. After age group adjustment, ADR detection methods did not show significant difference. The fatal PADRAd percentage was 1.58 % (95 % CI = -0.60 to 3.76; I 2 = 47 %). Paediatric and elderly studies showed a different causative drug pattern.

CONCLUSION

Variation in PADRAd across the studies can be explained by difference in study populations and data collection methods. Extrapolation of preventable reactions should be carried out considering all these factors with caution.

Development of the Liverpool Adverse Drug Reaction Avoidability Assessment Tool

Aim

To develop and test a new tool to assess the avoidability of adverse drug reactions that is suitable for use in paediatrics but which is also applicable to a variety of other settings.

Methods

The study involved multiple phases. Preliminary work involved using the Hallas scale and a modification of the existing Hallas scale, to assess two different sets of adverse drug reaction (ADR) case reports. Phase 1 defined, modified and refined a new tool using multidisciplinary teams. Phase 2 involved the assessment of 50 ADR case reports from a prospective study of paediatric inpatients by individual assessors. Phase 3 compared assessments with the new tool for individuals and groups in comparison to the ‘gold standard’ (the avoidability outcome set by a panel of senior investigators: an experienced clinical pharmacologist, paediatrician and pharmacist).

Main Outcome Measures

Inter-rater reliability (IRR), measure of disagreement and utilization of avoidability categories.

Results

Preliminary work—Pilot phase: results for the original Hallas cases were fair and pairwise kappa scores ranged from 0.21 to 0.36. Results for the modified Hallas cases were poor, pairwise kappa scores ranged from 0.06 to 0.16.

Phase 1: on initial use of the new tool, agreement between the two multidisciplinary groups was found on 13/20 cases with a kappa score of 0.29 (95% CI -0.04 to 0.62).

Phase 2: the assessment of 50 ADR case reports by six individual reviewers yielded pairwise kappa scores ranging from poor to good 0.12 to 0.75 and percentage exact agreement (%EA) ranged from 52–90%.

Phase 3: Percentage exact agreement ranged from 35–70%. Overall, individuals had better agreement with the ‘gold standard’.

Conclusion

Avoidability assessment is feasible but needs careful attention to methods. The Liverpool ADR avoidability assessment tool showed mixed IRR. We have developed and validated a method for assessing the avoidability of ADRs that is transparent, more objective than previous methods and that can be used by individuals or groups.

Epidemiology of adverse drug reactions in Europe: a review of recent observational studies

Adverse drug reactions (ADRs) cause considerable mortality and morbidity but no recent reviews are currently available for the European region. Therefore, we performed a review of all epidemiological studies quantifying ADRs in a European setting that were published between 1 January 2000 and 3 September 2014. Included studies assessed the number of patients who were admitted to hospital due to an ADR, studies that assessed the number of patients who developed an ADR during hospitalization, and studies that measured ADRs in the outpatient setting. In total, 47 articles were included in the final review. The median percentage of hospital admissions due to an ADR was 3.5 %, based on 22 studies, and the median percentage of patients who experienced an ADR during hospitalization was 10.1 %, based on 13 studies. Only five studies were found that assessed ADRs occurring in the outpatient setting. These results indicate that the occurrence of ADRs in the European hospital setting—both ADRs that result in hospitalization and ADRs that occur during the hospital stay—is significant. Furthermore, the limited number of studies that were performed in the outpatient setting identify a lack of information regarding the epidemiology of ADRs in this setting.

Identifying adverse drug reactions and drug-induced diseases using network-based drug mapping

Drugs are essential for the prevention and treatment of diseases. However, co-administration of multiple drugs may cause serious adverse drug reactions, which are usually known but sometimes unknown. Package inserts of prescription drugs are supposed to contain risks and side effects, but such information is not necessarily complete. At the core of efforts to improve prescription quality, there is reliance on the extent and quality of information used for decision of a medical doctor. To address this on-going need, GraphSAW provides users a comprehensive view on drug-related pharmacological and molecular information. The features of GraphSAW allow users to analyze drug cocktails for adverse drug reactions and drug-induced diseases. Network visualization by drug mapping enables exploring associative networks of drugs, pathways, and diseases to fully understand effects of drugs in an intuitive way. GraphSAW is meant to be a platform and starting point for health professionals and researchers for educational and scientific research in order to achieve substantial improvements in patient safety.

Comparing characteristics of adverse drug events between older and younger adults presenting to a Taiwan emergency department

To compare the proportion, seriousness, preventability of adverse drug events (ADEs) between the older adults (≥ 65 years old) and younger adults (<65 years old) presenting to the emergency department (ED), we conducted a prospective observational cohort study of patients 18 years and older presenting to the ED. For all ED visits between March 1, 2009, and Feb 28, 2010, investigators identified ADEs and assessed cases using the Naranjo adverse drug reaction probability scale. Outcomes (proportion, seriousness, and preventability of ADE, length of ED stay, and hospitalization) and associated variables were measured and compared between younger and older adults. The results showed that of 58,569 ED visits, 295 older adults, and 157 younger adults were diagnosed as having an ADE and included in our analysis. The proportion of ADEs leading to ED visits in the older group, 14.3 per 1000  (295/20,628), was significantly higher than the younger group of 4.1 per 1000  (157/37,941). The older group with ADE had a longer ED stay (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.9-6.4 for stay ≥ 24 hours) and larger proportion of preventable ADEs (OR 2.2, 95% CI 1.4-3.6) than the younger group, but there was no significant difference in terms of serious ADEs (OR 0.6, 95% CI 0.3-1.3 for fatal and life threatening) and hospitalization (OR 1.5, 95% CI 0.9-2.6) between the 2 groups. In addition, patients in the older group were more likely to be male, to have symptoms of fatigue or altered mental status, to involve cardiovascular, renal, and respiratory systems, and to have higher Charlson comorbidity index scores, higher number of prescription medications, and higher proportion of unintentional overdose. In conclusion, the proportion of ADE-related ED visits in older adults was higher than younger adults, and many of these were preventable. The most common drug categories associated with preventable ADEs in the older adults were antithrombotic agents, antidiabetic agents, and cardiovascular agents.

A systematic review of the prevalence and risk factors for adverse drug reactions in the elderly in the acute care setting

Adverse drug reactions (ADRs) are an important health issue. While prevalence and risk factors associated with ADRs in the general adult population have been well documented, much less is known about ADRs in the elderly population. The aim of this study was to review the published literature to estimate the prevalence of ADRs in the elderly in the acute care setting and identify factors associated with an increased risk of an ADR in the elderly. A systematic review of studies published between 2003 and 2013 was conducted in the Cochrane Database of Systematic Reviews, EMBASE, Google Scholar and MEDLINE. Key search terms included: “adverse drug reactions”, “adverse effects”, “elderly patients and hospital admission”, “drug therapy”, “drug adverse effects”, “drug related”, “aged”, “older patients”, “geriatric”, “hospitalization”, and “emergency admissions”. For inclusion in the review, studies had to focus on ADRs in the elderly and had to include an explicit definition of what was considered an ADR and/or an explicit assessment of causality, and a clear description of the method used for ADR identification, and had to describe factors associated with an increased risk of an ADR. Fourteen hospital-based observational studies exploring ADRs in the elderly in the acute care setting were eligible for inclusion in this review. The mean prevalence of ADRs in the elderly in the studies included in this review was 11.0% (95% confidence interval [CI]: 5.1%–16.8%). The median prevalence of ADRs leading to hospitalization was 10.0% (95% CI: 7.2%–12.8%), while the prevalence of ADRs occurring during hospitalization was 11.5% (95% CI: 0%–27.7%). There was wide variation in the overall ADR prevalence, from 5.8% to 46.3%. Female sex, increased comorbid complexity, and increased number of medications were all significantly associated with an increased risk of an ADR. Retrospective studies and those relying on identification by the usual treating team reported lower prevalence rates. From this review, we can conclude that ADRs constitute a significant health issue for the elderly in the acute care setting. While there was wide variation in the prevalence of ADRs in the elderly, based on the findings of this study, at least one in ten elderly patients will experience an ADR leading to or during their hospital stay. Older female patients and those with multiple comorbidities and medications appear to be at the highest risk of an ADR in the acute care setting.

Adverse drug reactions as a cause of admission to a Dublin-based university teaching hospital

BACKGROUND

A meta-analysis of 25 international studies suggests that 4.2-6.0% of medical admissions are the result of an adverse drug reaction (ADR). One Irish study has found that 8.8% of admissions to a university teaching hospital were attributable to ADRs.

AIM

To develop and evaluate a process to detect ADR-related medical admissions to a university teaching hospital in North Dublin.

METHODS

A screening process was developed to detect ADR-related admissions based on a previous Scottish study. Having evaluated the accuracy of the screening process in a large Dublin-based university teaching hospital, the same methodology was then applied to medical admissions occurring over a 9-day period.

RESULTS

The sensitivity and specificity of the screening process were 100 and 97%, respectively. The incidence of ADR-related hospitalization from 137 admissions was 5.1% (95% CI 1.4-8.8%). Of the ADRs, six were type A (predictable and preventable) and one was a type B (uncommon ADRs) reaction. Of the seven ADRs, two were considered to be unavoidable while five were potentially avoidable. High-risk medications namely anticoagulants, antiplatelets and antihypertensives were identified as causative medications.

CONCLUSIONS

This study outlines the feasibility of screening for ADR-related admission in the hospital setting. ADRs constitute an important and avoidable cause of hospital admission.

ADRIC: Adverse Drug Reactions In Children – a programme of research using mixed methods

Aims

To comprehensively investigate the incidence, nature and risk factors of adverse drug reactions (ADRs) in a hospital-based population of children, with rigorous assessment of causality, severity and avoidability, and to assess the consequent impact on children and families. We aimed to improve the assessment of ADRs by development of new tools to assess causality and avoidability, and to minimise the impact on families by developing better strategies for communication.

Review methods

Two prospective observational studies, each over 1 year, were conducted to assess ADRs in children associated with admission to hospital, and those occurring in children who were in hospital for longer than 48 hours. We conducted a comprehensive systematic review of ADRs in children. We used the findings from these studies to develop and validate tools to assess causality and avoidability of ADRs, and conducted interviews with parents and children who had experienced ADRs, using these findings to develop a leaflet for parents to inform a communication strategy about ADRs.

Results

The estimated incidence of ADRs detected in children on admission to hospital was 2.9% [95% confidence interval (CI) 2.5% to 3.3%]. Of the reactions, 22.1% (95% CI 17% to 28%) were either definitely or possibly avoidable. Prescriptions originating in the community accounted for 44 out of 249 (17.7%) of ADRs, the remainder originating from hospital. A total of 120 out of 249 (48.2%) reactions resulted from treatment for malignancies. Off-label and/or unlicensed (OLUL) medicines were more likely to be implicated in an ADR than authorised medicines [relative risk (RR) 1.67, 95% CI 1.38 to 2.02;p < 0.001]. When medicines used for the treatment of oncology patients were excluded, OLUL medicines were not more likely to be implicated in an ADR than authorised medicines (RR 1.03, 95% CI 0.72 to 1.48;p = 0.830). For children who had been in hospital for > 48 hours, the overall incidence of definite and probable ADRs based on all admissions was 15.9% (95% CI 15.0 to 16.8). Opiate analgesic drugs and drugs used in general anaesthesia (GA) accounted for > 50% of all drugs implicated in ADRs. The odds ratio of an OLUL drug being implicated in an ADR compared with an authorised drug was 2.25 (95% CI 1.95 to 2.59;p < 0.001). Risk factors identified were exposure to a GA, age, oncology treatment and number of medicines. The systematic review estimated that the incidence rates for ADRs causing hospital admission ranged from 0.4% to 10.3% of all children [pooled estimate of 2.9% (95% CI 2.6% to 3.1%)] and from 0.6% to 16.8% of all children exposed to a drug during hospital stay. New tools to assess causality and avoidability of ADRs have been developed and validated. Many parents described being dissatisfied with clinician communication about ADRs, whereas parents of children with cancer emphasised confidence in clinician management of ADRs and the way clinicians communicated about medicines. The accounts of children and young people largely reflected parents’ accounts. Clinicians described using all of the features of communication that parents wanted to see, but made active decisions about when and what to communicate to families about suspected ADRs, which meant that communication may not always match families’ needs and expectations. We developed a leaflet to assist clinicians in communicating ADRs to parents.

Conclusion

The Adverse Drug Reactions In Children (ADRIC) programme has provided the most comprehensive assessment, to date, of the size and nature of ADRs in children presenting to, and cared for in, hospital, and the outputs that have resulted will improve the management and understanding of ADRs in children and adults within the NHS. Recommendations for future research: assess the values that parents and children place on the use of different medicines and the risks that they will find acceptable within these contexts; focusing on high-risk drugs identified in ADRIC, determine the optimum drug dose for children through the development of a gold standard practice for the extrapolation of adult drug doses, alongside targeted pharmacokinetic/pharmacodynamic studies; assess the research and clinical applications of the Liverpool Causality Assessment Tool and the Liverpool Avoidability Assessment Tool; evaluate, in more detail, morbidities associated with anaesthesia and surgery in children, including follow-up in the community and in the home setting and an assessment of the most appropriate treatment regimens to prevent pain, vomiting and other postoperative complications; further evaluate strategies for communication with families, children and young people about ADRs; and quantify ADRs in other settings, for example critical care and neonatology.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Capture and documentation of coded data on adverse drug reactions: an overview

Allergic responses to prescription drugs are largely preventable, and incur significant cost to the community both financially and in terms of healthcare outcomes. The capacity to minimise the effects of repeated events rests predominantly with the reliability of allergy documentation in medical records and computerised physician order entry systems (CPOES) with decision support such as allergy alerts. This paper presents an overview of the nature and extent of adverse drug reactions (ADRs) in Australia and other developed countries, a discussion and evaluation of strategies which have been devised to address this issue, and a commentary on the role of coded data in informing this patient safety issue. It is not concerned with pharmacovigilance systems that monitor ADRs on a global scale. There are conflicting reports regarding the efficacy of these strategies. Although in many cases allergy alerts are effective, lack of sensitivity and contextual relevance can often induce doctors to override alerts. Human factors such as user fatigue and inadequate adverse drug event reporting, including ADRs, are commonplace. The quality of and response to allergy documentation can be enhanced by the participation of nurses and pharmacists, particularly in medication reconciliation. The International Classification of Diseases (ICD) coding of drug allergies potentially yields valuable evidence, but the quality of local and national level coded data is hampered by under-documenting and under-coding.

Implementation and evaluation of adverse drug reaction monitoring system in a tertiary care teaching hospital in Mumbai, India

Adverse drug reactions (ADR) are a significant cause of morbidity and mortality, often identified only post-marketingly. Improvement in current ADR reporting, including utility of underused or innovative methods, is crucial to improve patient safety and public health. Hospital-based monitoring is one of the methods used to collect data about drug prescriptions and adverse events. The aims of this study were to identify the most frequent ADRs recognized by the attending physicians, study their nature, and to target these ADRs in order to take future preventive measures. A prospective study was conducted over a 7-month period in an internal medicine department using stimulated spontaneous reporting for identifying ADRs. Out of the 254 admissions, 32 ADRs in 37 patients (14.56%) were validated from the total of 36 suspected ADRs in 41 patients. Female predominance was noted over males in case of ADRs. Fifty percent of total ADRs occurred due to multiple drug therapy. Dermatological ADRs were found to be the most frequent (68.75%), followed by respiratory, central nervous system and gastrointestinal ADRs. The drugs most frequently involved were antibiotics, anti-tubercular agents, antigout agents, and NSAIDs. The most commonly reported reactions were itching and rashes. Out of the 32 reported ADRs, 50% of the reactions were probable, 46.87% of the reactions were possible and 3.12% of the reactions were definite. The severity assessment done by using the Hartwig and Seigel scale indicated that the majority of ADRs were ‘Mild’ followed by ‘Moderate’ and ‘Severe’ reactions, respectively. Out of all, 75% of ADRs were recovered. The most potent management of ADRs was found to be drug withdrawal. Our study indicated that hospital based monitoring was a good method to detect links between drug exposure and adverse drug reactions. Adequate training regarding pharmacology and optimization of drug therapy might be helpful to reduce ADR morbidity and mortality.

Incidence and economic burden of adverse drug reactions among elderly patients in Ontario emergency departments: a retrospective study

Background: The rapid rise in the availability and use of pharmaceutical agents, and particularly polypharmacy, directly increases the risk for patients to experience adverse drug reactions (ADRs). There are few studies on the overall incidence and costs of ADRs.

Objective: The aim of this study was to estimate the incidence and costs of emergency department (ED) visits related to ADRs for patients greater than 65 years of age using administrative data, and to describe risk factors for experiencing severe ADRs.

Methods: We employed a retrospective cohort design based on population-based healthcare administrative clinical databases. Identification of ADR-related ED visits from the administrative database was based on International Classification of Diseases, 10th Revision-Canadian Enhancement (ICD-10-CA) codes for each ED visit. The incidence and costs of ADR-related ED visits and subsequent hospital admissions were estimated for all adults aged 66 years and above for the period April 2003–March 2008. Costs were standardized and reported in 2008 Canadian dollars. Logistic regression was used to detect risk factors for severe ADRs.

Results: Approximately 0.75% of total annual ED visits among adults aged 66 years and above were found to be ADR-related, and among these patients 21.6% were hospitalized. In 2007, the cost of ADR-related visits was $333 per ED visit and $7528 per hospitalization for a total annual cost of $13.6 million in Ontario, or an estimated $35.7 million in Canada. Severe ADRs were associated with sex, age, comorbid disease burden, multiple drugs, multiple pharmacies, newly prescribed drugs, recent ED visit, recent hospitalization and long-term care (LTC) residence.

Conclusions: ADRs are an important public health issue that threaten the safety of drug therapy and results in significant economic burden to the healthcare system. ED visits related to ADRs may be underestimated in retrospective studies using administrative data compared with prospective studies. Further research is needed to better understand the risk of experiencing severe ADRs among LTC residents.

Adverse Drug Reactions in Children--International Surveillance and Evaluation (ADVISE): a multicentre cohort study

BACKGROUND

A previous meta-analysis reported that 9.5% of hospitalized children suffered from an adverse drug reaction (ADR); however, reported incidences among studies varied.

OBJECTIVE

To enhance the knowledge of ADRs in paediatric hospitalized patients at a global level we investigated the incidence and characteristics of ADRs in hospitalized children in European and non-European countries.

METHODS

A prospective observational cohort study was conducted in academic and non-academic hospitals in five countries: Australia, Germany, Hong Kong, Malaysia and the UK. Children aged 0-18 years admitted during a 3-month period (between 1 October 2008 and 31 December 2009) were recruited. The main outcome measures were incidence, causality and outcome of ADRs.

RESULTS

A total of 1278 patients (1340 admissions) were included [Australia n = 146 (149 admissions), Germany n = 376 (407), Hong Kong n = 143 (149), Malaysia n = 300 (314) and the UK n = 313 (321)]. The median age was 2 years (interquartile range [IQR] 0-7). Patients received a total of 5367 drugs (median 3; IQR 2-5) and median length of hospital stay was 4 days (IQR 3-7). A total of 380 ADRs were identified in 211 patients. The resultant ADR incidence of 16.5% (95% CI 14.5, 18.7) varied significantly between countries (p < 0.001). The highest incidences were observed in Malaysia and the UK. 65.3% (n = 248) of ADRs were found to be probable, and 24% of the ADRs were serious, with one being fatal.

CONCLUSIONS

By comparing data from five countries in Europe, Asia and Australia we have shown that the incidence of ADRs in hospitalized children is at least as high as incidences published in adults. However, the variation between countries was mainly due to different populations and treatment strategies. Particular attention should be given to opioid use in hospitalized children.

Drug-induced blood consumption: the impact of adverse drug reactions on demand for blood components in German departments of internal medicine

Therapy for adverse drug reactions (ADRs) often results in the application of blood components. This study aims to assess the demand for blood components and the resulting economic burden (hospital perspective) in German hospitals induced by ADRs leading to admissions to departments of internal medicine. In this prospective study, ADRs leading to hospitalization were surveyed in four regional pharmacovigilance centres in Germany during the years 2000-2007. ADRs assessed as 'possible', 'likely' or 'very likely' were included. Market prices for blood components and hospitalization data were determined by desktop research. A probabilistic sensitivity analysis was performed. A total of 6099 patients were admitted to internal medicine departments because of an outpatient ADR of whom 1165 patients (19.1%; mean age, 73.0 ± 13.0 years) required treatment with blood components owing to major bleeding events. Overall consumption was 4185 erythrocyte concentrates (EC), 426 fresh frozen plasma (FFP) and 48 thrombocyte (TC) units. On the basis of statistical hospital data, we estimated a nationwide demand of approximately 132,020 EC, 13,440 FFP and 1515 TC units, resulting in total costs of €12.66 million per year for all German hospitals. Some 19.2% of all ADR cases were assessed as preventable. Theoretically, a nationwide decreased demand for blood components and a savings potential of €2.43 million per year could be achieved by preventing ADRs in Germany. Blood components are used in one-fifth (mainly gastrointestinal bleeding) of all ADRs, leading to hospitalizations in internal medicine departments. Both blood demand and hospital procurement costs can be significantly lowered by preventing ADRs.

Percentage of patients with preventable adverse drug reactions and preventability of adverse drug reactions--a meta-analysis

BACKGROUND

Numerous observational studies suggest that preventable adverse drug reactions are a significant burden in healthcare, but no meta-analysis using a standardised definition for adverse drug reactions exists. The aim of the study was to estimate the percentage of patients with preventable adverse drug reactions and the preventability of adverse drug reactions in adult outpatients and inpatients.

METHODS

Studies were identified through searching Cochrane, CINAHL, EMBASE, IPA, Medline, PsycINFO and Web of Science in September 2010, and by hand searching the reference lists of identified papers. Original peer-reviewed research articles in English that defined adverse drug reactions according to WHO's or similar definition and assessed preventability were included. Disease or treatment specific studies were excluded. Meta-analysis on the percentage of patients with preventable adverse drug reactions and the preventability of adverse drug reactions was conducted.

RESULTS

Data were analysed from 16 original studies on outpatients with 48797 emergency visits or hospital admissions and from 8 studies involving 24128 inpatients. No studies in primary care were identified. Among adult outpatients, 2.0% (95% confidence interval (CI): 1.2-3.2%) had preventable adverse drug reactions and 52% (95% CI: 42-62%) of adverse drug reactions were preventable. Among inpatients, 1.6% (95% CI: 0.1-51%) had preventable adverse drug reactions and 45% (95% CI: 33-58%) of adverse drug reactions were preventable.

CONCLUSIONS

This meta-analysis corroborates that preventable adverse drug reactions are a significant burden to healthcare among adult outpatients. Among both outpatients and inpatients, approximately half of adverse drug reactions are preventable, demonstrating that further evidence on prevention strategies is required. The percentage of patients with preventable adverse drug reactions among inpatients and in primary care is largely unknown and should be investigated in future research.

Epidemiology and characteristics of adverse drug reactions caused by drug-drug interactions

INTRODUCTION

Drug-drug interactions (DDIs) arise in numerous different ways, involving pharmacokinetic or pharmacodynamic mechanisms. Adverse drug reactions are a possible consequence of DDIs and health operators are often unaware of the clinical risks of certain drug combinations. Many papers on drug interactions have been published in recent years, but most of them focused on potential DDIs while few studies have been conducted on actual interactions.

AREAS COVERED

This paper reviews the epidemiology of actual DDIs in outpatients as well as in hospital settings and in spontaneous reporting databases. The incidence of actual DDIs is consistently lower than that of potential DDIs. However, the absolute number of patients involved is high, representing a significant proportion of adverse drug reactions. The importance of risk factors such as age, polypharmacy and genetic polymorphisms is also evaluated. The relevance and efficacy of tools for recognizing and preventing DDIs are discussed.

EXPERT OPINION

Potential DDIs far outnumber actual drug interactions. The potential for an adverse interaction to occur is often theoretical, and clinically important adverse effects occur only in the presence of specific risk factors. Several studies have shown the efficacy of computers in early detection of DDIs. However, a correct risk-benefit evaluation by the prescribing physician, together with a careful clinical, physiological and biochemical monitoring of patients, is essential. Future directions of drug interaction research include the increasing importance of pharmacogenetics in preventing DDIs and the evaluation of interactions with biological drugs.

Adverse drug reactions in Germany: direct costs of internal medicine hospitalizations

PURPOSE

German hospital reimbursement modalities changed as a result of the introduction of Diagnosis Related Groups (DRG) in 2004. Therefore, no data on the direct costs of adverse drug reactions (ADRs) resulting in admissions to departments of internal medicine are available. The objective was to quantify the ADR-related economic burden (direct costs) of hospitalizations in internal medicine wards in Germany.

METHODS

Record-based study analyzing the patient records of about 57,000 hospitalizations between 2006 and 2007 of the Net of Regional Pharmacovigilance Centers (Germany). All ADRs were evaluated by a team of experts in pharmacovigilance for severity, causality, and preventability. The calculation of accurate person-related costs for ADRs relied on the German DRG system (G-DRG 2009). Descriptive and bootstrap statistical methods were applied for data analysis.

RESULTS

The incidence of hospitalization due to at least 'possible' serious outpatient ADRs was estimated to be approximately 3.25%. Mean age of the 1834 patients was 71.0 years (SD 14.7). Most frequent ADRs were gastrointestinal hemorrhage (n = 336) and drug-induced hypoglycemia (n = 270). Average inpatient length-of-stay was 9.3 days (SD 7.1). Average treatment costs of a single ADR were estimated to be approximately €2250. The total costs sum to €434 million per year for Germany. Considering the proportion of preventable cases (20.1%), this equals a saving potential of €87 million per year.

CONCLUSIONS

Preventing ADRs is advisable in order to realize significant nationwide savings potential. Our cost estimates provide a reliable benchmark as they were calculated based on an intensified ADR surveillance and an accurate person-related cost application.

Health care use and costs of adverse drug events emerging from outpatient treatment in Germany: a modelling approach

BACKGROUND

This study's aim was to develop a first quantification of the frequency and costs of adverse drug events (ADEs) originating in ambulatory medical practice in Germany.

METHODS

The frequencies and costs of ADEs were quantified for a base case, building on an existing cost-of-illness model for ADEs. The model originates from the U.S. health care system, its structure of treatment probabilities linked to ADEs was transferred to Germany. Sensitivity analyses based on values determined from a literature review were used to test the postulated results.

RESULTS

For Germany, the base case postulated that about 2 million adults ingesting medications have will have an ADE in 2007. Health care costs related to ADEs in this base case totalled 816 million Euros, mean costs per case were 381 Euros. About 58% of costs resulted from hospitalisations, 11% from emergency department visits and 21% from long-term care. Base case estimates of frequency and costs of ADEs were lower than all estimates of the sensitivity analyses.

DISCUSSION

The postulated frequency and costs of ADEs illustrate the possible size of the health problems and economic burden related to ADEs in Germany. The validity of the U.S. treatment structure used remains to be determined for Germany. The sensitivity analysis used assumptions from different studies and thus further quantified the information gap in Germany regarding ADEs.

CONCLUSIONS

This study found costs of ADEs in the ambulatory setting in Germany to be significant. Due to data scarcity, results are only a rough indication.

Adverse drug reactions detected by stimulated spontaneous reporting in an internal medicine department in Romania

BACKGROUND

It is generally recognized that adverse drug reactions (ADRs) represent a major concern of health systems in terms of early recognition, proper management and prevention. The aims of this study were to identify the most frequent ADRs recognized by the attending physicians, study their nature and target these ADRs in order to take future preventive measures.

METHODS

A prospective study was conducted over a 12-month period in an internal medicine department using stimulated spontaneous reporting for identifying ADRs. All ADRs reported by physicians were followed up to the patient's discharge and evaluated by an independent group of pharmacologists. Causality, severity and preventability were assessed.

RESULTS

Of the 1854 admissions, 112 ADRs in 94 patients (5.07%) were validated from the total of 118 ADRs reported. The overall incidence of serious ADRs in the hospitalized patients was 4.7%. According to the MedDRA classification, the most frequent ADRs affected the gastrointestinal system, followed by metabolic and vascular systems. The drugs most frequently involved were cardiovascular agents, anticoagulants and NSAIDs. Drug interactions were responsible for 25.9% of ADRs. According to the selected preventability scale, 40.18% ADRs were classified as 'potentially preventable' and 9.82% 'definitely preventable'. Most of the ADRs were 'type A' reactions and as such could have been avoided simply by adjusting the doses or by avoiding drug interactions.

CONCLUSIONS

Serious ADRs in hospitalized patients are common and often preventable. Preventing strategies should target drug prescription. Adequate training regarding pharmacology and optimization of drug therapy might help reduce ADRs' morbidity and mortality.

[Is there an improvement of drug safety in Germany in recent years?]

The goal of drug therapy to prolong life or to improve the quality of life can be accomplished by modern drug therapy to a respectable degree. However, the risks of drug therapy have increased through more specific drugs and lead to often surprisingly multi-faceted side effects as in the case of biologicals. We have performed a systematic review of meta analyses, clinical studies, and reviews of the last five years concerned with adverse drug reactions (ADR) and adverse drug events (ADE). From these data emerges a distinct lack of reliable studies for Germany on incidence, severity and preventability of ADR and ADE; however, there are indications of their increase as is also evident from other countries. There are indications also for a better incidence management culture and better documentation. The step to utilize computerized physician order entry and decision support systems is a proven method to reduce medication related problems, leading also to reduction of in-hospital time and reduced drug expenses. Taking this decisive step to improve drug safety requires an appreciation of the magnitude of the problem and the determination to change an established but inferior system of drug administration in a fundamental way.

Adverse drug reactions in adult medical inpatients in a South African hospital serving a community with a high HIV/AIDS prevalence: prospective observational study

What is already known about this subject. Studies conducted primarily in developed countries have shown that adverse drug reactions (ADRs) are a significant cause of hospital admission, prolong hospital stay and consequently increase the cost of disease management in patients. Cardiovascular medicines, hypoglycaemic agents, nonsteroidal anti-inflammatory drugs and antibiotics are the most frequently implicated medicines in these studies. A large proportion of these ADRs have been shown to be preventable through improved drug prescribing, administration and monitoring for adverse effects. What this paper adds. This is the first Sub-Saharan African study in the HIV/AIDS era that describes the contribution of ADRs to patient morbidity, hospitalisation and mortality. Cardiovascular medicines and antiretroviral therapy contributed the most to community-acquired ADRs at the time of hospital admission while medicines used for opportunistic infections (such as antifungals, antibiotics and antituberculosis medicines were most frequently implicated in hospital acquired ADRs. ADRs in HIV-infected patients were less likely to be preventable.

AIMS

To describe the frequency, nature and preventability of community-acquired and hospital-acquired adverse drug reactions (ADRs) in a South African hospital serving a community with a high prevalence of human immunodeficiency virus (HIV)/ acquired immunodeficiency syndrome.

METHODS

A 3-month prospective observational study of 665 adults admitted to two medical wards.

RESULTS

Forty-one (6.3%) patients were admitted as a result of an ADR and 41 (6.3%) developed an ADR in hospital. Many of the ADRs (46.2%) were considered preventable, although less likely to be preventable in HIV-infected patients than in those with negative or unknown HIV status (community-acquired ADRs 2/24 vs. 35/42; P < 0.0001; hospital-acquired ADRs 3/25 vs. 14/26; P = 0.003). Patients admitted with ADRs were older than patients not admitted with an ADR (median 53 vs. 42 years, P = 0.003), but 60% of community-acquired ADRs at hospital admission were in patients <60 years old. Among patients <60 years old, those HIV infected were more likely to be admitted with an ADR [odds ratio (OR) 2.32, 95% confidence interval (CI) 1.17, 4.61; P = 0.017]. Among HIV-infected patients, those receiving antiretroviral therapy (ART) were more likely to be admitted with an ADR than those not receiving ART (OR 10.34, 95% CI 4.50, 23.77; P < 0.0001). No ART-related ADRs were fatal. Antibiotics and drugs used for opportunistic infections were implicated in two-thirds of hospital-acquired ADRs.

CONCLUSIONS

ADRs are an important, often preventable cause of hospitalizations and inpatient morbidity in South Africa, particularly among the elderly and HIV-infected. Although ART-related injury contributed to hospital admissions, many HIV-related admissions were among patients not receiving ART, and many ADRs were associated with medicines used for managing opportunistic infections.

Hospitalisations and emergency department visits due to drug-drug interactions: a literature review

PURPOSE

Our objective was to evaluate the incidence of adverse patient outcomes due to drug-drug interactions (D-DIs), the type of drugs involved and the underlying reason. As a proxy for adverse patient outcomes, emergency department (ED) visits, hospital admissions and re-hospitalisations were assessed.

METHODS

A literature search in the Medline and Embase database (1990-2006) was performed and references were tracked. An overall cumulative incidence was estimated by dividing the sum of the cases by the sum of the study populations.

RESULTS

Twenty-three studies were found assessing the relationship between D-DIs and ED-visits, hospitalisations or re-hospitalisations. The studies with a large study size showed low incidences and vice versa. D-DIs were held responsible for 0.054% of the ED-visits, 0.57% of the hospital admissions and 0.12% of the re-hospitalisations. In the elderly population, D-DIs were held responsible for 4.8% of the admissions. Drugs most often involved were NSAIDs and cardiovascular drugs. The reasons for admissions or ED-visits, which were most often found were GI-tract bleeding, hyper- or hypotension and cardiac rhythm disturbances.

CONCLUSION

This review provides information on the overall incidence of D-DIs as a cause of adverse patient outcomes, although there is still uncertainty about the impact of D-DIs on adverse patient outcomes. Our results suggest that a limited number of drugs are involved in the majority of cases and that the number of reasons for admission as a consequence of D-DIs seems to be modest.

Analysis of adverse drug reactions for preventability

Although preventability criteria have been assessed for all adverse drug reactions (ADRs) investigated at our institution over the past 12 years, a systematic evaluation of the data had not been performed. This project analysed preventability data previously collected to identify the potential areas for process improvements. A 3-year retrospective analysis was performed. All ADRs were categorised by drug, drug class, severity, probability of causality and preventability. Factors involved in preventability were assessed and tallied. Descriptive statistics was used to analyse the data. Most ADRs occurred prior to admission. In the outpatient setting, anticoagulants and anticonvulsants were associated with more preventable ADRs (pADRs) than other drug classes, followed by cardiotonic agents and non-steroidal anti-inflammatory drugs (NSAIDs). For ADRs that occurred in hospitalised patients, antibiotics and opiates were associated with approximately half of all pADRs. The preventability categories most frequently associated with ADRs prior to admission were presence of a toxic drug level and drug-drug interactions, while inappropriate dose, route or frequency was the most common preventability category for inpatient ADRs. The majority of pADRs were moderate in severity in both the in- and outpatient settings. Drugs and drug classes involved in pADRs differ in the in- and outpatient settings. Preventability categories also differ by setting. Most pADRs occur prior to admission in our healthcare system. This presents a challenge in terms of implementing the process changes to reduce the pADRs, as patients in the community are outside our control.

Anaesthetist's responses to patients' self-reported drug allergies

BACKGROUND

Patients with drug allergies are commonplace in anaesthetic practice. We investigated the incidence and nature of drug 'allergies' reported by surgical patients attending a hospital pre-admission clinic, and went on to ascertain to what degree drug allergies recorded in the records influenced drug prescribing during the patients' hospital stay and determine whether any adverse events occurred in relation to drug prescribing in this population.

METHODS

Patients attending for anaesthetic assessment at a Pre-Admission Clinic over a 30 week period were questioned concerning drug allergies. Medical records of these patients were then examined after their hospitalization to assess medications prescribed during that period.

RESULTS

Of 1260 patients attending the Pre-admission clinic during the study period 420 (33.4%) claimed to have a total of 644 individual drug 'allergies'. The most common agents implicated were antibiotics (n=272), opioid analgesics (n=118) and NSAIDs (n=62); the most common form of these reactions were dermatological (n=254) and nausea and vomiting (n=124). There were 41 self-reports specifically of anaphylaxis and a further 61 where there was significant respiratory system involvement.

CONCLUSIONS

The majority of the self-reported allergies were in fact simply accepted adverse effects of the drugs concerned. The patients' reported drug 'allergy' history was generally well respected by anaesthetists and other medical staff. There were 13 incidents, mainly involving morphine, where patients were given a drug to which they had claimed a specific allergy. There were 101 incidents in 89 patients where drugs of the same pharmacological group as that of their allergic drug were used. There were no untoward reactions in 84 patients who had claimed a prior adverse reaction to penicillin who were given cephalosporins. There were no sequelae from any other events. While anaesthetists generally respected patients self-reported 'allergies', more attention needs to be paid to the accurate recording of patients' events and a clear distinction should be made both in medical records and to the patient between true drug allergy and simple adverse drug reactions.