Identification of medication-related attendances at an A & E department

Adverse drug reactions, multimorbidity and polypharmacy: a prospective analysis of 1 month of medical admissions

OBJECTIVE

To ascertain the burden and associated cost of adverse drug reactions (ADRs), polypharmacy and multimorbidity through a prospective analysis of all medical admissions to a large university teaching hospital over a 1-month period.

DESIGN

Prospective observational study.

SETTING

Liverpool University Hospital Foundation National Health Service (NHS) Trust, England.

PARTICIPANTS

All medical admissions with greater than 24-hour stay over a 1-month period.

MAIN OUTCOME MEASURES

Prevalence of admissions due to an ADR and associated mortality, prevalence and association of multimorbidity and polypharmacy with ADRs, and estimated local financial cost of admissions where an ADR was a contributing or main reason for admission with projected costs for NHS in England.

RESULTS

There were 218 identified patient admissions with an ADR giving a prevalence of 18.4%. The majority of these (90.4%) were ADRs that directly resulted in or contributed to admission. ADRs thus accounted for 16.5% of total admissions. Those with an ADR were on average taking more medicines (10.5 vs 7.8, p<0.01) and had more comorbidities than those without an ADR (6.1 vs 5.2, p<0.01). Drugs most commonly implicated were diuretics, steroid inhalers, anticoagulants and antiplatelets, proton pump inhibitors, chemotherapeutic agents and antihypertensives. 40.4% of ADRs were classified avoidable or possibly avoidable. The mortality rate due to an ADR was 0.34%. The average length of stay for those with an ADR was 6 days. Direct 1-month cost to the Trust from ADR admissions was £490 716. Extrapolated nationally, the projected annual cost to the NHS in England is 2.21 billion.

CONCLUSION

The local prevalence of admission and mortality from ADRs is higher than previously reported. Important factors that could be contributing to this include polypharmacy and multimorbidity. ADRs place a significant burden on patients and healthcare services with associated financial implications. Reducing inappropriate polypharmacy should be a major aim for preventing ADRs.

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.

Prevalence of Drug-Related Emergency Department Visits at a Teaching Hospital in Malaysia

BACKGROUND

Data on the prevalence of adverse drug event (ADE)-related emergency department (ED) visits in developing countries are limited. Malaysia is located in South-East Asia, and, to our knowledge, no information exists on ADE-related ED visits.

OBJECTIVE

The objective of this study was to determine the prevalence, preventability, severity, and outcome of drug-related ED visits.

METHODOLOGY

A cross-sectional study was conducted in consenting patients who visited the ED of Hospital Universiti Sains Malaysia over a 6-week period. The ED physician on duty determined whether or not the visit was drug related according to set criteria. Other relevant information was extracted from the patient's medical folder by a clinical pharmacist.

RESULTS

Of the 434 consenting patients, 133 (30.6 %; 95 % confidence interval [CI] 26-35 %) visits were determined to be ADE related; 55.5 % were considered preventable, 11.3 % possibly preventable, and 33.1 % not preventable. Severity was classed as mild in 1.5 %, moderate in 67.7 %, and severe in 30.8 %. The most common ADEs reported were drug therapeutic failure (55.6 %) and adverse drug reactions (32.3 %). The most frequently implicated drugs were antidiabetics (n = 31; 23.3 %), antihypertensives (n = 28; 21.1 %), antibiotics (n = 13; 9.8 %), and anti-asthmatics (n = 11; 8.3 %). A total of 93 patients (69.9 %) were admitted to the ED for observation, 25 (18.8 %) were discharged immediately after consultation, and 15 (11.3 %) were admitted to the ward through the ED.

CONCLUSION

The prevalence of ADE-related ED visits was high; more than one-half of the events were considered preventable and one-third was classed as severe. As such, preventive measures will minimize future occurrences and increase patient safety.

Development of an Aggregated System for Classifying Causes of Drug-Related Problems

Background: More than 20 different types of classification systems for drug-related problems (DRPs) and their causes have been developed. Classification is necessary to describe and assess clinical, organizational, and economic impacts of DRPs through documentation of collected data. However, many researchers have judged classification systems incomplete when describing their data, and have modified them or developed their own. This variability between systems has made study comparisons difficult. Objectives: To perform a category-by-category comparison of the content of selected DRP classification systems to construct an aggregated cause-of-DRP classification system containing the content of all systems. Method: DRP classification systems were identified after a literature review, with 7 chosen based on their use in varied health care settings, geographical diversity, frequency of use, and method of development. These systems were critically analyzed, and the content of each category was compared and aggregated where appropriate. A hierarchy of categories was constructed to include all content from all systems. Any modifications that previous studies may have made to the 7 systems were also cross-referenced to ensure that no concepts were missing from the newly aggregated system. Clinical examples to optimize application, and instructions for when or when not to use categories, were developed. Interrater agreement for classification of the causes of DRPs from 10 medication reviews was performed between 3 clinical pharmacists and the authors’ gold standard. Results: We found variation in developmental methods, category descriptions, number and types of categories, and validation methods between the 7 selected systems, together with intermingling of categories identified as causes of DRPs with DRPs themselves. A hierarchical classification system was constructed consisting of 9 cause-of-DRP categories, 33 subcategories, and 58 sub-subcategories, for which interrater agreements were 82.5%, 74.6%, and 58.8%, respectively. Conclusion: An aggregated classification system was constructed through a unique and transparent developmental process that may provide the most comprehensive description of causes of DRPs to date. This may facilitate teaching of pharmaceutical care, comparisons of clinical practice, and measurement of the effectiveness of pharmaceutical care interventions.

Risk factors for hospital admissions associated with adverse drug events

STUDY OBJECTIVE

To identify predictors of hospital admissions associated with adverse drug events (ADEs) and to determine the preventability of ADEs in patients admitted to two hospitals.

DESIGN

Prospective observational study.

SETTING

Medical admission units at two British National Health Service hospitals in the United Kingdom.

PATIENTS

3904 adults age 16 years or older who were admitted to the two hospitals between June 2006 and November 2007.

MEASUREMENTS AND MAIN RESULTS

Clinical pharmacists identified hospital admissions associated with drug-related problems by using medical record review, supplemented by patient interview for those identified as having an ADE. The contribution of ADEs to hospital admission and the causality, severity, and preventability of the events were independently assessed by a multidisciplinary clinical team. Multivariate logistic regression was used to identify predictors of hospital admissions associated with ADEs, and a maximum-likelihood multinomial model was used to examine predictors of the preventability of ADEs. Of the 3904 patients included in the analysis, 439 (11.2%) were judged by the review panel to have experienced ADEs. Of these, 209 patients (47.6%) experienced preventable ADEs. Four independent variables were found to have significant relationships with ADE admissions and preventability of ADEs: patient age, length of time since starting new drug, total number of prescription drugs, and hospital site. Drug classes most commonly associated with preventable ADEs were antiplatelet drugs, anticoagulants, diuretics (loop and thiazide diuretics), angiotensin-converting enzyme inhibitors, and antiepileptic drugs.

CONCLUSION

Adverse drug events are an important cause of hospital admission. Better systems for health care practitioners to identify patients at high risk of preventable hospital admissions associated with ADEs (e.g., age > 65 years old, receiving more than five drugs, and starting new high-risk drugs) should be implemented in order to minimize the risks to patients and the burden on the health care system.

Drug-related emergency department visits by elderly patients presenting with non-specific complaints

Background

Since drug-related emergency department (ED) visits are common among older adults, the objectives of our study were to identify the frequency of drug-related problems (DRPs) among patients presenting to the ED with non-specific complaints (NSC), such as generalized weakness and to evaluate responsible drug classes.

Methods

Delayed type cross-sectional diagnostic study with a prospective 30 day follow-up in the ED of the University Hospital Basel, Switzerland. From May 2007 until April 2009, all non-trauma patients presenting to the ED with an Emergency Severity Index (ESI) of 2 or 3 were screened and included, if they presented with non-specific complaints. After having obtained complete 30-day follow-up, two outcome assessors reviewed all available information, judged whether the initial presentation was a DRP and compared their judgment with the initial ED diagnosis. Acute morbidity (“serious condition”) was allocated to individual cases according to predefined criteria.

Results

The study population consisted of 633 patients with NSC. Median age was 81 years (IQR 72/87), and the mean Charlson comorbidity index was 2.5 (IQR 1/4). DRPs were identified in 77 of the 633 cases (12.2%). At the initial assessment, only 40% of the DRPs were correctly identified. 64 of the 77 identified DRPs (83%) fulfilled the criteria “serious condition”. Polypharmacy and certain drug classes (thiazides, antidepressants, benzodiazepines, anticonvulsants) were associated with DRPs.

Conclusion

Elderly patients with non-specific complaints need to be screened systematically for drug-related problems.

Trial Registration

ClinicalTrials.gov: NCT00920491

Prevalence of medication-related problems among patients with renal compromise in an Indian hospital

WHAT IS KNOWN AND OBJECTIVE

Patients suffering from renal dysfunction often have multiple medical conditions either as a cause or as a consequence of their renal disease. These patients receive an average of 10-12 medications daily leading to complex dosing schedules and are more likely to develop medication-related problems (MRPs). The objectives of this study were to determine the nature and extent of MRPs in renally compromised patients and to explore the potential clinical significance of the MRPs. The potential for a clinical pharmacist to contribute towards resolving or preventing some of these MRPs was also explored.

METHODS

A prospective study was conducted for a period of 9 months in the renal unit of Jagadguru Shri Shivaratheeshwara (JSS) Medical College Hospital, Mysore, India. Patients undergoing dialysis on outpatient basis and patients who were admitted under the care of or referred to the nephrologists for renal dysfunction from other specialties were reviewed. Patterns of the MRPs were identified using an adapted Hepler and Strand criteria. The potential clinical significance of the MRPs and the contribution of the clinical pharmacist in resolving or minimizing some of the MRPs were also explored.

RESULTS AND DISCUSSION

Three hundred and twenty-seven MRPs were identified with 308 patients reviewed. The incidence of MRPs was found to be 1·06 ± 0·85 per patient reviewed. The most common MRP identified in our study was overdose (19·3%) followed by adverse drug reactions (19·0%). Cardiovascular agents (33·6%) followed by anti-infective agents (26·3%) were the most common therapeutic classes of medication implicated in causing MRPs. Twenty-six per cent of the MRPs identified were explored to be potentially moderate or major in clinical significance. The clinical pharmacists' recommendations were accepted in 97% of the cases, which resulted in a change in therapy in 83% of the cases.

WHAT IS NEW AND CONCLUSION

Medication-related problems are frequent in renally compromised patients in our patient population. The high level of acceptance of clinical pharmacist's recommendations by the nephrologists demonstrates that clinical pharmacists may help improve overall patient care in this setting.

[Incidence rate of adverse drug effects in a hospital emergency unit and its associated factors]

INTRODUCTION

Adverse drug effects (ADEs) are the reason for 0.86% to 38.2% of hospital emergency admissions, and a large percentage of them are avoidable. Rational prescription and pharmacotherapy monitoring decrease the appearance of such health problems.

METHOD

Study performed in a tertiary hospital emergency unit with patients selected using a two-phase random sample. The information was obtained from a validated questionnaire and from the clinical history. The data were grouped according to the following cause-effect schema: 1-Potential risk factors for an ADE. 2-Effects likely to be caused by drugs. 3-Consequences of ADEs. 4-Potential confounding factors. The information obtained was evaluated by four independent evaluators using the Dader method.

RESULTS

840 patients were included in the study, and 33% of them came to the emergency unit due to an ADE. ADEs were more frequently observed in female patients, those with higher drug consumption, older patients, those with an underlying illness and in those from underprivileged backgrounds. The factors determining risk of an ADE are the quantity of drugs consumed, sex and the health practices index.

DISCUSSION

One third of hospital emergency admissions were due to ADEs, and these were associated with the same factors found in other studies (number of drugs consumed, female sex, age and social background). In addition, we observed that ADEs are predominant in patients with low values on the health practices index, and in those with underlying illnesses.