Hospitalisations caused by adverse drug reactions (ADR): a meta-analysis of observational studies

Modelling drug-related morbidity in Sweden using an expert panel of pharmacists'

BACKGROUND

Drug-related morbidity (DRM) is common and to some extent preventable, and associated with considerable costs in patients attending hospital. In outpatients and in the general public corresponding data are limited, but pharmacists' expert opinion has suggested high rates of DRM also in US ambulatory care. It is unknown if the results are applicable in Sweden today.

OBJECTIVE

To estimate the proportions of patients with DRM and preventable DRM and the cost-of-illness (COI) of DRM in Sweden based on pharmacists' expert opinion.

SETTING

Swedish healthcare.

METHOD

The study applied a conceptual model of DRM based on a decision tree. An expert panel of pharmacists determined the probabilities of therapeutic outcomes of medication therapy. The COI analysis included direct costs from the healthcare perspective. Sensitivity analyses were performed for variations in probabilities and pathway costs.

MAIN OUTCOME MEASURE

DRM included new medical problems (adverse drug reactions, drug dependence and intoxications) and therapeutic failures (insufficient effects of medicines and morbidity due to untreated indication).

RESULTS

The expert panel estimated that 61 ± 14 % (mean ± SD) of all patients attending healthcare suffered from DRM, of which 29 ± 8 % suffered from new medical problems, 18 ± 6 % from therapeutic failures, and 15 ± 7 % from a combination of both. The DRM was considered preventable in 45 ± 15 % of the patients with DRM. The estimated COI was EUR 997 per patient attending healthcare, corresponding to an annual cost of EUR 6,600 million to the Swedish healthcare system. The COI ranged from EUR 490 to EUR 1,314 when varying the participants' probabilities of DRM and clinical outcomes from the first to the third quartile. Of the pathway costs, the COI was most sensitive to variation in the cost of prolonged hospital stay (COI range EUR 953-1,306).

CONCLUSION

According to pharmacists' expert opinion, a large proportion of patients in Sweden experience DRM and preventable DRM, and the estimated COI of DRM is extensive. Since observational studies have not addressed the burden of DRM to the general public, this study adds the pharmacists' perception on DRM. Other healthcare professionals' perceptions on DRM need to be investigated in future studies.

Clinical pharmacology in old persons

The epidemiological transition, with a rapid increase in the proportion in the global population aged over 65 years from 11% in 2010 to 22% in 2050 and 32% in 2100, represents a challenge for public health. More and more old persons have multimorbidities and are treated with a large number of medicines. In advanced age, the pharmacokinetics and pharmacodynamics of many drugs are altered. In addition, pharmacotherapy may be complicated by difficulties with obtaining drugs or adherence and persistence with drug regimens. Safe and effective pharmacotherapy remains one of the greatest challenges in geriatric medicine. In this paper, the main principles of geriatric pharmacology are presented.

Drug induced interstitial lung disease

With an increasing number of therapeutic drugs, the list of drugs that is responsible for severe pulmonary disease also grows. Many drugs have been associated with pulmonary complications of various types, including interstitial inflammation and fibrosis, bronchospasm, pulmonary edema, and pleural effusions. Drug-induced interstitial lung disease (DILD) can be caused by chemotherapeutic agents, antibiotics, antiarrhythmic drugs, and immunosuppressive agents. There are no distinct physiologic, radiographic or pathologic patterns of DILD, and the diagnosis is usually made when a patient with interstitial lung disease (ILD) is exposed to a medication known to result in lung disease. Other causes of ILD must be excluded. Treatment is avoidance of further exposure and systemic corticosteroids in patients with progressive or disabling disease.

Adverse drug reactions in older patients: an Italian observational prospective hospital study

Background

In adults over 65 years of age, the frequency of adverse drug reaction (ADRs) related hospital admissions is higher than in younger adults, and the frequency of ADRs occurring during hospital stay highly ranges. The review was designed to evaluate the frequency of ADRs, both resulting in hospital admission and occurring during the hospital stay of older patients, while identifying the types of reactions and the associated drugs.

Methods

Age, sex, date, and diagnosis of admission of all patients aged 65 and over admitted in three geriatric wards of University Hospital of Verona, Italy, from February to July 2009 were registered by nurses on a special form. In the specific cases of admissions caused by an ADR as well as in the cases of an ADR occurring during the hospital stay, the type of reactions and the suspected drugs were also registered by nurses and physicians involved in the study.

Results

During the six months of the study, 1023 patients matched the inclusion criteria and were included in the study. One hundred fourteen hospital admissions (11.1%) were caused by ADRs, while 256 patients (25.0%) had an ADR during their hospital stay. The duration of hospital stay was significantly longer in patients who developed an ADR during their time in hospital, 18.7 (95% CI: 17.2–20.1) days versus 12.6 (95% CI: 11.9–13.3) days. Electrolyte disorders, gastrointestinal disorders, anemia, and International Normalized Ratio increase were the more frequent observed ADRs, with diuretics, antithrombotic agents, and antibacterials as the main involved drugs. Our study confirms that ADRs are an important cause of hospitalization in older patients. In addition, the frequency of ADRs occurring during hospital stay is high and causes prolonged hospitalization.

Adverse drug reaction-related hospitalizations in persons aged 55 years and over: a population-based study in the Netherlands

BACKGROUND

Elderly individuals appear to be particularly at risk of developing adverse drug reactions (ADRs) because of higher rates of polypharmacy, age-related pharmacokinetic changes, pharmacodynamic variations and substantial co-morbidity levels. Thus, the increasing contribution of elderly individuals to the total population means ADR-related hospitalizations are expected to become more frequent. However, a recent study conducted in the Netherlands found that ADR-related hospitalizations had stabilized during the years 1997-2007. Nonetheless, this study did not take into account the number of medicines used.

OBJECTIVES

Therefore, the objectives of this study were to describe the association between age and sex, and the risk of an adverse drug reaction (ADR)-related hospitalization in persons aged 55 years and over in the Netherlands and to correlate these ADR-related hospitalizations with the number of dispensed medicines over the same period.

METHODS

Data on hospital admissions were obtained from the Dutch nationwide registry of hospital discharges. Data from Statistics Netherlands were used to obtain population demographics. Data on dispensed medicinal products were obtained from the Dutch Foundation for Pharmaceutical Statistics. Analyses were performed by calculating relative risks (RRs).

RESULTS

Those aged ≥75 years were at a more than 4-fold increased risk of being hospitalized in comparison with those aged 55-64 years (RR 4.15; 95% CI 4.12, 4.18). In addition, female sex was associated with an increased risk of an ADR-related hospitalization (RR 1.05; 95% CI 1.03, 1.08) in comparison with males. When taking into account the number of dispensings, elderly ≥75 years of age were at an increased risk of being hospitalized for an ADR due to anticoagulants (RR 2.20; 95% CI 2.12, 2.28), antidiabetic agents (RR 3.53; 95% CI 3.39, 3.66), salicylates (RR 1.70; 95% 1.54, 1.86) and antirheumatics (RR 2.19; 95% CI 2.06, 2.33).

CONCLUSION

In our study, we showed that elderly aged ≥75 years were at increased risk of an ADR-related hospitalization. Given that the number of elderly and very old will continue to grow, it is of pivotal importance to further endorse drug safety in this vulnerable patient group.

Frequency of adverse drug reactions in hospitalized patients: a systematic review and meta-analysis

PURPOSES

To perform a comprehensive systematic review of prospective studies about frequency of adverse drug reactions (ADRs) occurring during hospitalization (ADR(In) ), including a thorough study quality assessment, meta-analysis and heterogeneity evaluation.

METHODS

Systematic review of several databases: Pubmed, EMBASE, CINAHL, Cochrane, ISI, International Pharmaceutical Abstracts, Scirus, NHS economic, and others, as well as manual search. Inclusion criteria were: prospective studies (assessing all patients before discharge, by a specialized team, at least once a week); with data about ADRs occurring during hospitalization, using WHO's or similar definition of ADR. Two independent reviewers assessed eligibility criteria, extracted data, and evaluated risk of bias.

RESULTS

From 4139 studies initially found, 22 were included. Meta-analysis indicate that ADRs may occur in 16.88% (CI95%: 13.56,20.21%) of patients during hospitalization; however, this estimate has to be viewed with caution because there was significant heterogeneity (I²  = 99%). The most significant moderators of heterogeneity were risk of bias, population, ward, and methodology for ADR identification. Low risk of bias studies adjusted for population (pediatric versus adult) had I²  = 0%.

CONCLUSIONS

These data are useful as a broad characterization of in-hospital ADRs and their frequency. However, due to heterogeneity, our estimates are crude indicators. The wide variation in methodologies was one of the most important moderators of heterogeneity (even among studies using intensive monitoring). We suggest criteria to standardize methodologies and reduce the risk of bias.

Minimizing inappropriate medications in older populations: a 10-step conceptual framework

The increasing burden of harm resulting from the use of multiple drugs in older patient populations represents a major health problem in developed countries. Approximately 1 in 4 older patients admitted to hospitals are prescribed at least 1 inappropriate medication, and up to 20% of all inpatient deaths are attributable to potentially preventable adverse drug reactions. To minimize this drug-related iatrogenesis, we propose a quality use of medicine framework that comprises 10 sequential steps: 1) ascertain all current medications; 2) identify patients at high risk of or experiencing adverse drug reactions; 3) estimate life expectancy in high-risk patients; 4) define overall care goals in the context of life expectancy; 5) define and confirm current indications for ongoing treatment; 6) determine the time until benefit for disease-modifying medications; 7) estimate the magnitude of benefit versus harm in relation to each medication; 8) review the relative utility of different drugs; 9) identify drugs that may be discontinued; and 10) implement and monitor a drug minimization plan with ongoing reappraisal of drug utility and patient adherence by a single nominated clinician. The framework aims to reduce drug use in older patients to the minimum number of essential drugs, and its utility is demonstrated in reference to a hypothetic case study. Further studies are warranted in validating this framework as a means for assisting clinicians to make more appropriate prescribing decisions in at-risk older patients.

Targeting outpatient drug safety: recommendations of the Dutch HARM-Wrestling Task Force

BACKGROUND

Two Dutch observational studies (HARM [Hospital Admissions Related to Medication] and IPCI [Integrated Primary Care Information]) have shown that approximately 5% of all unplanned hospital admissions are associated with adverse drug events (ADEs), of which 40-46% are potentially preventable. These studies prompted the initiation of a Dutch multidisciplinary task force, which was assigned to reduce the number of prescriber-related hospital admissions related to medications (HARMs) in a quick-win way.

OBJECTIVE

The aim of the study was to identify the most relevant ADEs and to develop a limited number of recommendations for concrete interventions, which should be feasible and relatively easy to convert into computerized drug safety alerts.

METHOD

To identify the major ADEs, crude data of HARM and IPCI were reanalysed and compared with different international studies, followed by structured literature searches for further characterization of the identified ADEs, their risk factors and potential risk-reduction strategies. Based on this information, the Task Force drew up general and drug-specific recommendations. As the recommendations of the Task Force are a mixture of evidence- and expert-based risk-reducing strategies, they have been graded in accordance with the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology.

RESULTS

Seven pharmacologically predictable ADEs associated with ten drug classes were responsible for more than half of all potentially preventable hospital admissions in the IPCI and HARM studies, which was comparable to the results of international studies. Gastrointestinal and other bleedings were the most frequent ADE, followed by disturbances of diabetes mellitus control, electrolyte disturbances, fractures, renal insufficiency and heart failure. Nine general and 34 drug-specific recommendations were developed.

CONCLUSIONS

As HARMs constitute a significant public health problem, the Task Force underlines the need to implement its recommendations as soon as possible. They do not replace existing guidelines, but reinforce, complement and fine-tune existing Dutch and international guidelines. Further research is still required to assess the cost consequences and cost effectiveness of some recommendations, and to monitor the implementation of the recommendations and their effect on the incidence of potentially preventable HARMs.

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.

Year in review: medication mishaps in the elderly

OBJECTIVE

This paper reviews articles from 2010 that examined medication mishaps (ie, medication errors and adverse drug events [ADEs]) in the elderly.

METHODS

The MEDLINE and EMBASE databases were searched for English-language articles published in 2010 using a combination of search terms including medication errors, medication adherence, medication compliance, suboptimal prescribing, monitoring, adverse drug events, adverse drug withdrawal events, therapeutic failures, and aged. A manual search of the reference lists of the identified articles and the authors' article files, book chapters, and recent reviews was conducted to identify additional publications. Five studies of note were selected for annotation and critique. From the literature search, this paper also generated a selected bibliography of manuscripts published in 2010 (excluding those previously published in the American Journal of Geriatric Pharmacotherapy or by one of the authors) that address various types of medication errors and ADEs in the elderly.

RESULTS

Three studies focused on types of medication errors. One study examined underuse (due to prescribing) as a type of medication error. This before-and-after study from the Netherlands reported that those who received comprehensive geriatric assessments had a reduction in the rate of undertreatment of chronic conditions by over one third (from 32.9% to 22.3%, P < 0.05). A second study focused on reducing medication errors due to the prescribing of potentially inappropriate medications. This quasi-experimental study found that a computerized provider order entry clinical decision support system decreased the number of potentially inappropriate medications ordered for patients ≥ 65 years of age who were hospitalized (11.56 before to 9.94 orders per day after, P < 0.001). The third medication error study was a cross-sectional phone survey of managed-care elders, which found that more blacks than whites had low antihypertensive medication adherence as per a self-reported measure (18.4% vs 12.3%, respectively; P < 0.001). Moreover, blacks used more complementary and alternative medicine (CAM) than whites for the treatment of hypertension (30.5% vs 24.7%, respectively; P = 0.005). In multivariable analyses stratified by race, blacks who used CAM were more likely than those who did not to have low antihypertensive medication adherence (prevalence rate ratio = 1.56; 95% CI, 1.14-2.15; P = 0.006). The remaining two studies addressed some form of medication-related adverse patient events. A case-control study of Medicare Advantage patients revealed for the first time that the use of skeletal muscle relaxants was associated significantly with an increased fracture risk (adjusted odds ratio = 1.40; 95% CI, 1.15-1.72; P < 0.001). This increased risk was even more pronounced with the concomitant use of benzodiazepines. Finally, a randomized controlled trial across 16 centers in France used a 1-week educational intervention about high-risk medications and ADEs directed at rehabilitation health care teams. Results indicated that the rate of ADEs in the intervention group was lower than that in the usual care group (22% vs 36%, respectively, P = 0.004).

CONCLUSION

Information from these studies may advance health professionals' understanding of medication errors and ADEs and may help guide research and clinical practices in years to come.

Adverse drug reaction-related hospitalizations in persons aged 55 years and over: a population-based study in the Netherlands

BACKGROUND

Elderly individuals appear to be particularly at risk of developing adverse drug reactions (ADRs) because of higher rates of polypharmacy, age-related pharmacokinetic changes, pharmacodynamic variations and substantial co-morbidity levels. Thus, the increasing contribution of elderly individuals to the total population means ADR-related hospitalizations are expected to become more frequent. However, a recent study conducted in the Netherlands found that ADR-related hospitalizations had stabilized during the years 1997-2007. Nonetheless, this study did not take into account the number of medicines used.

OBJECTIVES

Therefore, the objectives of this study were to describe the association between age and sex, and the risk of an adverse drug reaction (ADR)-related hospitalization in persons aged 55 years and over in the Netherlands and to correlate these ADR-related hospitalizations with the number of dispensed medicines over the same period.

METHODS

Data on hospital admissions were obtained from the Dutch nationwide registry of hospital discharges. Data from Statistics Netherlands were used to obtain population demographics. Data on dispensed medicinal products were obtained from the Dutch Foundation for Pharmaceutical Statistics. Analyses were performed by calculating relative risks (RRs).

RESULTS

Those aged ≥75 years were at a more than 4-fold increased risk of being hospitalized in comparison with those aged 55-64 years (RR 4.15; 95% CI 4.12, 4.18). In addition, female sex was associated with an increased risk of an ADR-related hospitalization (RR 1.05; 95% CI 1.03, 1.08) in comparison with males. When taking into account the number of dispensings, elderly ≥75 years of age were at an increased risk of being hospitalized for an ADR due to anticoagulants (RR 2.20; 95% CI 2.12, 2.28), antidiabetic agents (RR 3.53; 95% CI 3.39, 3.66), salicylates (RR 1.70; 95% 1.54, 1.86) and antirheumatics (RR 2.19; 95% CI 2.06, 2.33).

CONCLUSION

In our study, we showed that elderly aged ≥75 years were at increased risk of an ADR-related hospitalization. Given that the number of elderly and very old will continue to grow, it is of pivotal importance to further endorse drug safety in this vulnerable patient group.

Prevalence of potentially preventable unplanned hospitalizations caused by therapeutic failures and adverse drug withdrawal events among older veterans

Background. Studies of drug-related hospitalizations have focused on adverse drug reactions, but few data are available on therapeutic failures (TFs) and adverse drug withdrawal events (ADWEs) leading to hospitalization among community-dwelling older adults. Thus, we sought to describe the prevalence of unplanned hospitalizations caused by TFs and ADWEs. In addition, we evaluated factors associated with these events in a nationally representative sample of older Veterans. Methods. This study included 678 randomly selected unplanned hospitalizations of older (age ≥ 65 years) Veterans between December 1, 2003, and November 9, 2006. The main outcomes were hospitalizations caused by a TF and/or an ADWE as determined by a pair of health professionals from review of medication charts and application of the Therapeutic Failure Questionnaire and/or Naranjo ADWE algorithm, respectively. Preventability (ie, medication error) of the admission was also assessed. Results. Thirty-four TFs and eight ADWEs involving 54 drugs were associated with 40 (5.9%) Veterans' hospitalizations; of these admissions, 90.0% (36/40) were rated as potentially preventable mostly due to medication nonadherence and suboptimal prescribing. The most common TFs that occurred were heart failure exacerbations (n = 8), coronary heart disease symptoms (n = 6), tachyarrhythmias (n = 3), and chronic obstructive pulmonary disease exacerbations (n = 3). Half (4/8) of the ADWEs that occurred were cardiovascular in nature. Multivariable logistic regression modeling indicated that black Veterans (adjusted odds ratio 2.92, 95% CI 1.25-6.80) were significantly more likely to experience a TF-related admission compared with white Veterans. Conclusions. TF-related unplanned hospitalizations occur more frequently than ADWE-related admissions among older Veterans. Almost all TFs and/or ADWEs are potentially preventable.

[Results of integrating pharmaceutical care in an Acute Geriatric Unit]

OBJECTIVE

To evaluate whether the integration of pharmaceutical care in an acute geriatric unit can promote the detection of potentially inappropriate drug prescriptions (PIP) and adverse drug events (ADE), and if this can improve patient and caregiver information at hospital discharge.

METHOD

Descriptive prospective study in older patients admitted for acute care in the Geriatric Department of a university hospital. On admission, a pharmacist recorded a comprehensive drug history from the patient, caregiver and other available sources, and reviewed preadmission treatments in order to detect adverse drug events (using the 3(rd) Granada consensus criteria) and potentially inappropriate prescriptions (using STOPP-START criteria). At hospital discharge, the pharmacist informed patients and caregivers about the treatment and gave them computer generated written information for all drugs prescribed.

RESULTS

In a 9 month period 189 patients (84.7% of all admissions) were included in the pharmaceutical care program (71.9% women, mean age 87.2±5.5 years). After analysing 1523 prescriptions (mean drugs/patient 8.1±3.3), 356 (23.4%) potentially inappropriate prescriptions and 580 (38.1%) adverse drug events were detected (1.9 PIP and 3.2 ADE per patient). Almost three-quarters (74.2%) of the patients had at least one PIP: STOPP (48.9%) and START (26.9%). The most frequent adverse drug event was an untreated health problem. The pharmacist offered verbal and written information to 74.7% of the discharged patients.

CONCLUSION

Adding pharmaceutical care to the multidisciplinary activity of an acute geriatric care unit enables a great number of potentially inappropriate prescriptions and adverse drug events to be detected, and increases patient and caregiver information at hospital discharge.

Outcomes of polypharmacy in nursing home residents

This article provides a comprehensive review of the outcomes of polypharmacy in nursing homes. Our review had some limitations. First, we only included studies beginning in 1990, and significant earlier studies are not included. Only English language articles were included. We only researched studies from MEDLINE, and may have missed studies based on our search terms and search tools. There are many definitions of polypharmacy in the literature, including number of medications or inappropriate medications. In this review, we defined polypharmacy as a high number of medications, but not inappropriate medications. It was not surprising that polypharmacy was consistently associated with an increased number of potentially inappropriate drugs. The majority of studies were viewed showed that polypharmacy was associated with increased ADEs, increased DDIs, and increased hospitalizations. We were surprised that polypharmacy was not consistently linked with falls, fractures, and mortality. For the mortality studies, it has been postulated that perhaps some patients receiving 10 or more medications may have been moribund or receiving end-of-life or hospice care. It is possible that the number of medications is not as important as the number of potentially in appropriate drugs. There need to be more studies on these outcomes, using different definitions of polypharmacy. Polypharmacy was associated with increased costs. The drug-related morbidity and mortality, including those resulting from inappropriate medications and increased staff time, led to increased costs. Use of consultant pharmacists has been shown to decrease polypharmacy costs.

Applicability of an adapted medication appropriateness index for detection of drug-related problems in geriatric inpatients

BACKGROUND

High drug consumption by older patients and the presence of many drug-related problems require careful assessment of drug therapy, for which a structured approach is recommended.

OBJECTIVE

The purpose of our study was to evaluate the applicability of an adapted version of the Medication Appropriateness Index (MAI) in 50 geriatric inpatients at the time of admission.

METHODS

We reviewed, for 432 prescribed drugs, indication, right choice, dosage, directions, drug-disease interactions, drug-drug interactions, and duration of therapy. In addition, adverse drug reactions were evaluated, resulting in 8 questions per drug. MAI scores were attributed independently by a geriatrician and by a clinical pharmacist, and differences between them were assessed. Furthermore, the relationship between MAI score and drug-related hospital admission was explored.

RESULTS

Mean summed MAI scores of 13.7 according to the geriatrician and 13.6 according to the pharmacist were obtained. The highest scores were found for drugs for the central nervous and the urinary tract system; the highest scores per question were detected for right choice, adverse drug reactions, and drug-drug interactions. A good agreement between the scores of the geriatrician and the pharmacist was found: intraclass correlation coefficient was 0.91 and overall κ value was 0.71. A significantly higher MAI score was found for drug-related hospital admissions (P = 0.04 for the geriatrician and P = 0.03 for the pharmacist).

CONCLUSIONS

This adapted MAI score seems useful for detection of drug-related problems in geriatric inpatients and reliable with a low inter-rater variability and positive correlation between high score and drug-related hospital admission. We consider further application of the adapted MAI for teaching and training of clinical pharmacists, and as a systematic approach for detection of drug-related problems by the clinical pharmacists in our hospital.

Prevalence of unplanned hospitalizations caused by adverse drug reactions in older veterans

OBJECTIVES

To describe the prevalence of unplanned hospitalizations caused by adverse drug reactions (ADRs) in older veterans and to examine the association between this outcome and polypharmacy after controlling for comorbidities and other patient characteristics.

DESIGN

Retrospective cohort.

SETTING

Veterans Affairs Medical Centers.

PARTICIPANTS

Six hundred seventy-eight randomly selected unplanned hospitalizations of older (aged ≥ 65) veterans between October 1, 2003, and September 30, 2006.

MEASUREMENTS

Naranjo ADR algorithm, ADR preventability, and polypharmacy (0-4, 5-8, and ≥9 scheduled medications).

RESULTS

Seventy ADRs involving 113 drugs were found in 68 (10%) hospitalizations of older veterans, of which 25 (36.8%) were preventable. Extrapolating to the population of more than 2.4 million older veterans receiving care during the study period, 8,000 hospitalizations may have been unnecessary. The most common ADRs that occurred were bradycardia (n = 6; beta-blockers, digoxin), hypoglycemia (n = 6; sulfonylureas, insulin), falls (n = 6; antidepressants, angiotensin-converting enzyme inhibitors), and mental status changes (n = 6; anticonvulsants, benzodiazepines). Overall, 44.8% of veterans took nine or more outpatient medications and 35.4% took five to eight. Using multivariable logistic regression and controlling for demographic, health-status, and access-to-care variables, polypharmacy (≥9 and 5-8) was associated with greater risk of ADR-related hospitalization (adjusted odds ratio (AOR) = 3.90, 95% confidence interval (CI) = 1.43-10.61 and AOR = 2.85, 95% CI = 1.03-7.85, respectively).

CONCLUSION

ADRs, determined using a validated causality algorithm, are a common cause of unplanned hospitalization in older veterans, are frequently preventable, and are associated with polypharmacy.

Potentially inappropriate prescribing in elderly: assessing doctor knowledge, confidence and barriers

INTRODUCTION

Inappropriate medication prescribing by doctors is an important preventable cause of morbidity and mortality in the elderly. This study investigates doctor knowledge about potentially inappropriate prescribing (PIP) in elderly, their confidence in prescribing for the elderly and explores perceived barriers.

METHODS

Family and Internal Medicine resident and attending doctors at three teaching hospitals were asked to complete a survey. Six clinical vignettes based on the 2003 Beers criteria were used to evaluate doctor knowledge about medications to avoid in the elderly. Confidence in prescribing for the elderly and perceived barriers to appropriate prescribing in elderly was assessed using a 5-point Likert scale.

RESULTS

Eighty-nine doctors completed the survey, for a response rate of 45%. Forty-four per cent of surveyed doctors estimated that over 25% of their practice consisted of patients 65 years or older. When knowledge of PIP was assessed via vignettes, the mean correct response was 3.9 (SD: 1.1, min = 1, max = 6). Only 14% of those doctors scoring ≤4 vignettes correctly had used the Beers criteria for prescribing; 31% of the doctors answering ≥5 vignettes correctly had used the Beers criteria (P = 0.08). Overall, 75% of doctors felt confident about their prescribing irrespective of their knowledge scores. Seventy per cent of surveyed doctors cited at least seven different barriers to appropriate prescribing in elderly.

CONCLUSIONS

Many primary care doctors possess a poor knowledge of PIP and are unaware of prescribing guidelines such as the Beers criteria. Our survey indicates that doctor usage of the Beers criteria might correlate with improved judgement in prescribing for the elderly. Most doctors report multiple barriers to appropriate prescribing in the elderly. Lack of formal education about prescribing guidelines was the only barrier that correlated with the doctors' level of training.

Criteria for drug selection in frail elderly persons

BACKGROUND

Elderly patients with multiple morbidities and polypharmacy are at an increased risk of adverse drug events (ADEs). Appropriate prescribing, preserving the balance between drug effectiveness and safety, and treatment adherence may prevent these ADEs. In this study, we investigated which drug properties, such as effectiveness, safety, clinical experience and convenience, are relevant to the choice of medicine most appropriate for frail elderly patients.

OBJECTIVES

The primary aim of this study was to develop a set of criteria to assist in the selection of the most appropriate drug within a drug class for the treatment of frail elderly patients. A secondary goal was to test the usefulness of the set of criteria in the prescription of antipsychotics for delirium and behavioural and psychological symptoms of dementia (BPSD).

METHODS

Thirty-one criteria potentially relevant to the choice of appropriate drugs for frail elderly patients were selected on the basis of a literature search in MEDLINE (1966-2008), EMBASE (1947-2008) and the Cochrane Library (1993-2008). This list was reviewed by 46 experts (24 physicians, 22 pharmacists), who scored each item for relevance in clinical practice on a scale from 1 to 10 (where 1 is not important and 10 is very important). By consensus, the authors selected the most relevant criteria for the final set of criteria. The usefulness of the final set of criteria was assessed with regard to the prescription of antipsychotics for delirium and BPSD.

RESULTS

The final set of 23 items consisted of 3 items on effectiveness, 14 on safety, including pharmacokinetic and pharmacodynamic criteria, 3 on clinical experience and 3 on convenience. Assessment using these criteria of the appropriateness of antipsychotics prescribed for delirium and BPSD revealed that certain drugs should be prescribed with caution to patients with Parkinson's disease and Lewy body dementia.

CONCLUSIONS

The criteria identified in this study, selected on the basis of a literature review and clinical expert opinion, represent a promising approach for determining the appropriateness of a drug for use in frail elderly individuals relative to alternative drugs for the same indication or from the same class.

Allergic diseases in the elderly

Demographic distribution of the population is progressively changing with the proportion of elderly persons increasing in most societies. This entails that there is a need to evaluate the impact of common diseases, such as asthma and other allergic conditions, in this age segment. Frailty, comorbidities and polymedication are some of the factors that condition management in geriatric patients. The objective of this review is to highlight the characteristics of allergic diseases in older age groups, from the influence of immunosenescence, to particular clinical implications and management issues, such as drug interactions or age-related side effects.

Prescribing quality for older people in Norwegian nursing homes and home nursing services using multidose dispensed drugs

PURPOSE

To examine and compare the quality of drug prescribing for older patients in nursing homes and home nursing services.

METHODS

Cross-sectional study comprising 11,254 patients aged ≥ 65 years in nursing homes (n = 2986) and home nursing services (n = 8268). Potentially inappropriate medications were identified by using the Norwegian General Practice criteria and drug-drug interactions through a Norwegian Web-based tool. The impact of care setting on exposure to selected drug groups, potentially inappropriate medications, and drug interactions was calculated, adjusting for patients' age, gender, and number of drugs used.

RESULTS

Patients in nursing homes and home nursing services used on average 5.7 (SD = 2.6) multidose dispensed regular drugs. Twenty-six percent used at least one potentially inappropriate medication, 31% in nursing homes and 25% in home nursing services, p < .001. Concomitant use of three or more psychotropic and/or opioid drugs was the criterion most commonly identified in nursing homes (18%) and home nursing services (9%), p < .001. Compared with nursing homes, more patients in home nursing services used cardiovascular drugs and fewer patients used psychotropic drugs. Altogether, 8615 drug-drug interactions were identified in 55% of patients, 48% in nursing homes and 57% in home nursing services, p < .001.

CONCLUSIONS

There are significant differences in the quality of drug prescribing in nursing homes compared with home nursing services. Explanations as to why these differences exist need to be further explored.

The prevalence of herbal medicine home use and concomitant use with pharmaceutical medicines in Jamaica

ETHNOPHARMACOLOGICAL RELEVANCE

The work described in this paper aimed to study the prevalence of herbal medicine use in treating illness and concomitant use with pharmaceutical medicines in Jamaica.

MATERIALS AND METHODS

A survey using a structured questionnaire was administered by a trained interviewer to randomly selected adults in systematically selected households within randomly selected urban and rural clusters. Categorical data analysis was performed using Stata version 10 software.

RESULTS

91.4%(372/407) of selected people agreed to participate. 72.6%(270/372) self-medicated with herbs within the previous year. Commonly treated were illnesses of the respiratory system (RS, 77.8%(210/270)), gastro-intestinal tract (GIT, 53.3%(144/270)) and health maintenance using tonics (29.6%(80/270)). 26.7%(72/270) of respondents used pharmaceuticals concomitantly with medicinal plants. Commonly treated were illnesses of the RS (20.4%(55/270)), GIT (13.7%(37/270)) and hypertension (10.0%(27/270)). 19.4% (14/72) of physicians knew of such practices. There was significant association of herb use with/without drugs with age (p<0.001), employment status (p<0.001), religion (p=0.004), gender (p=0.02) and educational level (p=0.031). Thus prevalence of herb use alone was greatest amongst people aged 35-44 and 45-54 years; those employed; Rastafarians; those without health insurance; males and people who had completed secondary education. Whilst prevalence of concomitant herb-drug use was greater amongst people aged 65 years and older; those retired; those of religions other than Rastafarians and Christians, females and people who had attained primary education and below.

CONCLUSIONS

Self-medication with herbs in Jamaica is highly prevalent and highest for self-limiting conditions of the RS, GIT and health maintenance with tonics. Concomitant herb and drug use is highest for self-limiting conditions of the RS, GIT and hypertension, and the use of combined therapy highlights the need for investigations on potential drug-herb interactions. Physicians have limited awareness and knowledge of such concomitant usage, further highlighting the need for increased dialogue with patients, knowledge of medicinal plants and their uses and a heightened pharmacovigilance to avoid adversities that may arise from potential drug-herb interactions.

Pharmacogenomic technologies: a necessary "luxury" for better global public health?

BACKGROUND

Pharmacogenomic technologies aim to redirect drug development to increase safety and efficacy of individual care. There is much hope that their implementation in the drug development process will help respond to population health needs, particularly in developing countries. However, there is also fear that novel pharmacogenomic drugs will remain too costly, be designed for the needs of the wealthy nations, and so constitute an unnecessary "luxury" for most populations. In this paper, we analyse the promise that pharmacogenomic technologies hold for improving global public health and identify strategies and challenges associated with their implementation.

DISCUSSION

This paper evaluates the capacity of pharmacogenomic technologies to meet six criteria described by the University of Toronto Joint Centre for Bioethics group: 1) impact of the technology, 2) technology appropriateness, 3) capacity to address local burdens, 4) feasibility to be implemented in reasonable time, 5) capacity to reduce the knowledge gap, and 6) capacity for indirect benefits. We argue that the implementation of pharmacogenomic technologies in the drug development process can positively impact population health. However, this positive impact depends on how and for which purposes the technologies are used. We discuss the potential of these technologies to stimulate drug discovery in the case of rare (orphan diseases) or neglected diseases, but also to reduce acute adverse drug reactions in infectious disease treatment and prevention, which promises to improve global public health.

CONCLUSIONS

The implementation of pharmacogenomic technologies may lead to the development of drugs that appear to be a "luxury" for populations in need of numerous interventions that are known to have a demonstrable impact on population health (e.g., secure access to potable water, reduction of social inequities, health education). However, our analysis shows that pharmacogenomic technologies do have the potential to redirect drug development and distribution so as to improve the health of vulnerable populations. Strategies should thus be developed to better direct their implementation towards meeting the needs and responding to the realities of populations of the developing world (i.e., social, cultural and political acceptability, and local health burdens), making pharmacogenomic technologies a necessary "luxury" for global public health.

Use of potentially inappropriate medicines in elderly: A prospective study in medicine out-patient department of a tertiary care teaching hospital

Objective:

The present study was undertaken with the aim to detect extent of drug use in elderly at medicine outpatient department at tertiary care hospital and to evaluate inappropriate prescribing with the help of Beers' criteria 2002.

Materials and Methods:

The study was carried out at medicine out patient department of our hospital. 407 geriatric patients were included during the study period of three and half months. The data was collected in a proforma which included the patients' details and the prescriptions.

Results:

The results reveal that 7.42% of total drugs were prescribed in an inappropriate manner and 23.59% of total patients received at least one inappropriate drug prescription. Administration of a drug which is avoided in elderly forms a common category of inappropriate drug use. Antihistamines, anticholinergic, sedatives and hypnotics and cardiac glycosides are the most common drug groups prescribed in inappropriate manner.

Conclusion:

To conclude, this study shows high prevalence of inappropriate use of drugs in geriatric practice suggesting urgent need for sincere efforts to improve the situation.

An easy intervention to improve short-term adherence to medications in community-dwelling older outpatients. A pilot non-randomised controlled trial

Background

Complex interventions to improve compliance to pharmacological treatment in older people have given mixed results and are not easily applicable in clinical practice. The aim of this study was to test the short-term efficacy on self-reported medication adherence of an easy intervention in which the patient or caregiver was asked to transcribe the pharmacological treatment while it was dictated to him/her by the doctor.

Methods

Pilot non-randomised controlled trial involving 108 community-dwelling outpatients aged 65+ (54 in the intervention arm, 54 controls) referred to a geriatric service from May to July 2009 and prescribed by the geriatrician a change in therapy. The intervention was applied at the end of the visit to the person managing the medications, be it the elder or his/her caregiver. Outcome of the study was the occurrence of any adherence error, assessed at a one-month follow-up by means of a semi-structured interview.

Results

The socio-demographic, functional and clinical characteristics of the two compared groups were similar at baseline. At a one-month follow-up 43 subjects (40%) had made at least one adherence error, whether unintentional or intentional. In the intervention group the prevalence of adherence errors was lower than in controls (20% vs 59%; adjusted odds ratio 0.16, 95% confidence interval 0.07 - 0.39; p < 0.001) after adjusting for the person managing the medications, the adherence errors at baseline and for the number of prescribed drugs.

Conclusions

In an older outpatient population the intervention considered was effective in reducing the prevalence of adherence errors in the month following the visit.

Trial registration

Australian and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000347965

Determinants of patient-reported medication errors: a comparison among seven countries

OBJECTIVE

Medication errors are a frequent cause of adverse drug events and a major concern for patient safety. This study compared the predictors of error among seven countries (Australia, Canada, New Zealand, the United Kingdom, the United States, Germany and the Netherlands).

METHODS

We conducted a cross-sectional study using the 2007 Commonwealth Fund International Health Policy Survey data. The outcome was patient-reported error in the past 2 years. Possible predictors were studied using logistic regression.

RESULTS

Eleven thousand nine hundred and ten respondents were included in this analysis, of which 1291 respondents (11%) had experienced error. Poor coordination of care was a shared concern of all seven countries [adjusted odds ratios (ORs) ranged from 2.1 (95% CI: 1.3-3.5) to 3.0 (95% CI: 2.1-4.5)]. Cost-related barriers to medical services/medicines was also a predictor in six countries [ORs ranged from 1.9 (95% CI: 1.5-2.6) to 2.6 (95% CI: 1.5-4.6)]. Other common risk factors across countries included seeing multiple specialists, multiple chronic conditions, hospitalisation and multiple emergency room visits. Cross-country heterogeneity in contributing factors included age and specific chronic condition. Number of medications, number of doctor visits, household income and education level were not associated with error in most countries.

CONCLUSION

Poor coordination of care is a key risk factor in all seven countries. Cost-related barriers were also associated with an increased likelihood of error. The major challenge for all countries for error prevention is better communication among multiple healthcare providers and more structured organisation of care across healthcare settings.

Quality of drug prescribing in older patients: is there a problem and can we improve it?

Older patients are at high risk of suboptimal prescribing (overuse, underuse and misuse of drugs), which can lead to serious adverse drug reactions (ADR). About one in four patients admitted to hospital are prescribed at least one inappropriate medication and up to 20% of all inpatient deaths are attributed to potentially preventable ADR. Lists of drugs to avoid (unnecessary or where risks outweigh benefits) and drugs not to be omitted (strong indications if there are no contraindications) can assist in identifying suboptimal prescribing although, to date, no trials have established the ability of such screening, by itself, to improve prescribing quality. Remedial strategies proven to be effective in randomized trials include detailed appraisal of medication lists by multidisciplinary teams, which involve geriatricians and close liaison with specialist clinical pharmacists. A multifaceted quality improvement strategy is proposed that includes an aspirational target of no more than five different drugs be regularly prescribed to vulnerable older patients. Achieving this target involves prioritizing drug selection on the basis of strength of indication which may run counter to current disease-specific clinical guideline recommendations based on trials that have excluded most older patients. Such a strategy is worthy of further evaluation in a multicentre randomized trial.

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.

Public pharmacovigilance communication: a process calling for evidence-based, objective-driven strategies

As a contribution to the debate on how best to communicate information on the effective and safe use of medicines to patients, healthcare professionals and the general public, this article proposes to distinguish between communication and transparency purposes, and to test a strategic health communication approach. Any organization aiming to improve medicines use could adapt this approach to its remits and legal obligations. The approach includes agreeing measurable communication objectives through shared problem ownership of all concerned parties, evidence-based design and a cyclic process for planning, implementation and evaluation of communication as a public health intervention. The evidence base, which supplements risk assessment for product- and situation-specific communication on safety concerns, would be derived from research into drug utilization, medical decision making and risk perception, as well as from the participation of patients and healthcare professionals. It is crucial to address the practical questions and concerns of medicine users and to find out why unfavourable patterns of medicine use persist, in order to develop behaviour change models for overcoming these obstacles. For this purpose, appropriate models for facilitating the participation of medicine users in the risk management process will need to be explored. Such two-way communication would inform risk assessment as well as the analysis of risk minimization options, allow for agreement upon communication objectives and enable understandable, attractive communication materials to be designed. The communication programme should use mixed media and repetition of messages for long-term success. This would require cooperation within healthcare and medical information systems. An evaluation of the effectiveness of the communication should support the sustainability of the programme and provide lessons for the future. Given its mission, the pharmacovigilance community has the standing and duty to expand its scale of action and take the initiative in advancing risk management through a scientific approach to improving public communication for the safety of patients.

Sex-related differences in hospital admissions attributed to adverse drug reactions in the Netherlands

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Women are more at risk for developing adverse drug reactions (ADRs) due to differences in pharmacokinetics, pharmacodynamics and drug use. ADRs regularly lead to hospital admissions.

WHAT THIS STUDY ADDS

There are differences between the sexes in hospital admissions attributed to ADRs. The risk of being hospitalized with an ADR varies between the sexes in the type of reaction and the causative drug.

AIM

Adverse drug reactions (ADRs) are a major burden in health care, regularly leading to hospital admission, morbidity or death. Women tend to have a higher risk of adverse drug reactions with a 1.5 to 1.7-fold greater risk than men. Our primary aim was to study differences in ADR-related hospitalizations between the sexes.

METHODS

We conducted a nationwide study of all ADR-related hospitalizations in the period between 2000 and 2005 in the Netherlands, which were selected from all 9,287,162 hospital admissions in this period. ADR-drug group combinations with at least 50 admissions in one of the sexes were selected. Relative risks and confidence intervals were calculated with respect to total admissions and total prescriptions with men as reference.

RESULTS

In total, 0.41% of the 4,236,368 admissions in men (95% CI 0.40, 0.42%) and 0.47% of the 5,050,794 admissions in women (95% CI 0.46, 0.48%) were attributed to an ADR by medical specialists (57% of all ADR-related admissions were in women). Differences between the sexes in risk for ADR-related hospitalization were found for antineoplastic and immunosuppressive drugs, antirheumatics, anticoagulants and salicylates, cardiovascular and neurological drugs, steroids and antibiotics. In certain drug categories, risks for hospitalization changed after taking into account total drug prescriptions.

CONCLUSION

In all different drug classes, significant differences exist between the sexes in ADR-related hospital admissions. Cardiovascular drugs account for the most pronounced differences between men and women. More research is needed to explain the clear sex differences in ADR-related hospital admissions.

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.

Pharmacy counselling models: a means to improve drug use

BACKGROUND AND OBJECTIVE

Failure to achieve the intended benefit of medical treatment is recognized as an immense problem. The study objective was to examine the usefulness of counselling models containing key questions to facilitate the identification of drug-related problems (DRPs), and to follow up on both pharmacy practitioner and patient experiences.

METHODS

Fifty-one pharmacies in Sweden were recruited, along with matching controls. Patients of six therapeutic groups were selected for the counselling model intervention. DRPs were documented in the Swedish DRP database. A telephone follow-up with the patients and a questionnaire survey with the pharmacy practitioners were conducted. An additional follow-up was made in patients sending a representative to pick up their prescribed medications at the pharmacy.

RESULTS AND DISCUSSION

In all, 880 DRPs were documented in patients with 8100 prescriptions (10·9%). The DRP documentation rates in study pharmacies were, in general, superior to the control pharmacy rates. DRPs were identified in 24·8% of the non-steroidal anti-inflammation drug (NSAID) patients using a representative to pick up their medications, compared with 9·2% in patients visiting the pharmacy themselves. Of the patients who took part in the follow-up, 94% said that they received suggestions on problem resolution, and twice as many DRPs were reported resolved vs. unresolved. Most patients and pharmacy practitioners were pleased with the new practice.

CONCLUSION

The practice of counselling models appears to be a means to improve drug use. More DRPs were found in patients sending a representative to pick up their medications than in patients visiting the pharmacy themselves.

Inverting compliance, increasing concerns: aging, mental health, and caring for a trustful patient

Why, after 40 years of intensive research, is adherence to treatment still an issue? This paper suggests a possible solution to an apparently unsolvable problem: reconceptualizing adherence. To understand how adherence can affect key personnel in any western health system, this study focuses on community nurses working with older mental health patients in Quebec. When they spoke about adherence, nurses presented an idealized image of the nurse-patient relationship, namely, the caring nurse and the trustful patient. However, this idealization cannot be reduced only to questions of power and paternalism. By reconceptualizing adherence as a 'matter of concern', health professionals and researchers alike might come to understand individual care situations within a broader notion of conflicts in patient care.

[Pharmacologically-induced neurocatastrophes]

Drug-induced adverse reactions represent a significant health problem in developed countries. These events cause 5% of hospital admissions and are one of the main causes of mortality. Neurological manifestations are among the most frequent. This article reviews catastrophic cerebrovascular situations and confusional syndromes, as well as epilepsy, structural encephalopathy, neuromuscular disorders, catastrophic movement disorders and infections, all of which can be drug-induced.

Impact of sample size on variation of adverse events and preventable adverse events: systematic review on epidemiology and contributing factors

OBJECTIVES

To perform a systematic review of the frequency of (preventable) adverse events (AE/PAE) and to analyse contributing factors, such as sample size, settings, type of events, terminology, methods of collecting data and characteristics of study populations.

REVIEW METHODS

Search of Medline and Embase from 1995 to 2007. Included were original papers with data on the frequency of AE or PAE, explicit definition of study population and information about methods of assessment. Results were included with percentages of patients having one or more AE/PAE. Extracted data enclosed contributing factors. Data were abstracted and analysed by two researchers independently.

RESULTS

156 studies in 152 publications met our inclusion criteria. 144/156 studies reported AE, 55 PAE (43 both). Sample sizes ranged from 60 to 8,493,876 patients (median: 1361 patients). The reported results for AE varied from 0.1% to 65.4%, and for PAE from 0.1% to 33.9%. Variation clearly decreased with increasing sample size. Estimates did not differ according to setting, type of event or terminology. In studies with fewer than 1000 patients, chart review prevailed, whereas surveys with more than 100,000 patients were based mainly on administrative data. No effect of patient characteristics was found.

CONCLUSIONS

The funnel-shaped distribution of AE and PAE rates with sample size is a probable consequence of variation and can be taken as an indirect indicator of study validity. A contributing factor may be the method of data assessment. Further research is needed to explain the results when analysing data by types of event or terminology.

Trends of adverse drug reactions related-hospitalizations in Spain (2001-2006)

Background

Adverse drug reactions (ADR) are a substantial cause of hospital admissions. We conducted a nationwide study to estimate the burden of hospital admissions for ADRs in Spain during a six-year period (2001-2006) along with the associated total health cost.

Methods

Data were obtained from the national surveillance system for hospital data (Minimum Basic Data Set) maintained by the Ministry of Health and Consumer Affairs, and covering more than 95% of Spanish hospitals. From these admissions we selected all hospitalization that were code as drug-related (ICD-9-CM codes E), but intended forms of overdoses, errors in administration and therapeutics failure were excluded. The average number of hospitalizations per year, annual incidence of hospital admissions, average length of stay in the hospital, and case-fatality rate, were calculated.

Results

During the 2001-2006 periods, the total number of hospitalized patients with ADR diagnosis was 350,835 subjects, 1.69% of all acute hospital admissions in Spain. The estimated incidence of admissions due to ADR decreased during the period 2001-2006 (p < 0.05). More than five percent of patients (n = 19,734) died during an ADR-related hospitalization. The drugs most commonly associated with ADR-related hospitalization were antineoplastic and immunosuppressive drugs (n = 75,760), adrenal cortical steroids (n = 47,539), anticoagulants (n = 26,546) and antibiotics (n = 22,144). The costs generated by patients in our study increased by 19.05% between 2001 and 2006.

Conclusions

Approximately 1.69% of all acute hospital admissions were associated with ADRs. The rates were much higher for elderly patients. The total cost of ADR-related hospitalization to the Spanish health system is high and has increased between 2001 and 2006. ADRs are an important cause of admission, resulting in considerable use of national health system beds and a significant number of deaths.

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.

Qualitative insights into general practitioners views on polypharmacy

Background

Polypharmacy is common among older people. The purpose of this study is to describe GPs' views and beliefs on polypharmacy in order to identify the role of the GP in relation to improving prescribing behaviour. The awareness of these often established beliefs is key for understanding behaviour and promoting change which can guide action towards more rational prescribing.

Methods

A qualitative descriptive methodology was used with semi-structured interviews. Interviews were conducted with 65 GPs from the region of Aalst, a district of a mixed urban and rural population in Belgium. The aim of the study was to describe the GPs' perspectives on polypharmacy in primary care.

Results

GPs acknowledge that polypharmacy is a problem in their older patient population, especially because of the risk of adverse drug reactions, interactions and lowered adherence. GPs mention that difficulties in keeping an overview of the exact medication intake is an important problem caused by polypharmacy. The patients' strong belief in their medication and self-medication are seen as important barriers in reducing the number of drugs taken. Next to these patient related factors, there are some factors related to the prescriber, such as the lack of regular evaluation of the medication schedule by GPs and the involvement of several prescribers, especially in a hospital setting. According to the respondents, prevention and evidence based medicine guidelines often induce polypharmacy.

Conclusions

GPs point out that polypharmacy is an important problem in their older patient population. They see an important role for themselves in optimizing drug regimens for their patients. However, they do not have a readymade solution for polypharmacy. The limited set of options for addressing polypharmacy leave GPs feeling powerless to tackle the problem. There is a need for simple GP friendly tools and access to pharmacotherapeutic advice. Future research in this area and interventions seeking to improve prescribing for the elderly will have to focus on practical tools and take into account the GPs' sense of helplessness.