Clinical implications from drug-drug and drug-disease interactions in older people

Associations of polypharmacy with frailty severity and each frailty phenotype in community-dwelling older adults: Itabashi Longitudinal Study on Aging

AIM

Although polypharmacy and frailty are concerns in older adults, there is limited understanding of their association, particularly regarding frailty severity and its phenotypes within this population. This study aimed to examine the association between polypharmacy and frailty severity or frailty phenotypes in community-dwelling older Japanese adults.

METHODS

This cross-sectional study included 1021 older adults from the Itabashi Longitudinal Study on Aging. Men accounted for 45.4%, and the mean age (standard deviation) was 77.9 (5.1) years. Participants were classified into frail (n = 67), pre-frail (n = 543), and robust (n = 411) groups using the revised Japanese Cardiovascular Health Study criteria. Polypharmacy was defined as using five or more self-reported prescription drugs. Ordinal and binomial logistic regression analyses examined the association between polypharmacy and frailty severity or frailty phenotypes (weight loss, weakness, exhaustion, slowness, and low activity). These models were adjusted for age, sex, body mass index, number of comorbidities, living status, employment status, years of education, as well as drinking and smoking habits.

RESULTS

The prevalence of frailty in participants with and without polypharmacy was 10.1% and 5.0%, respectively. Participants with polypharmacy were more likely to have frailty (adjusted odds ratio [95% confidence interval], 1.89 [1.40-2.57]), weight loss (1.81 [1.00-3.27]), weakness (1.50 [1.08-2.09]), and slowness (2.25 [1.29-3.94]) compared with the no-polypharmacy group.

CONCLUSIONS

Polypharmacy was associated with frailty severity and three frailty phenotypes. Longitudinal studies are required to investigate whether polypharmacy can predict the development and progression of frailty. Geriatr Gerontol Int 2024; 24: 196-201.

Common gastrointestinal drug-drug interactions in geriatrics and the importance of careful planning

INTRODUCTION

Polypharmacy, which uses multiple medications to treat chronic illnesses, is common among elderly patients. However, it can lead to drug interactions, especially with gastrointestinal (GI) medicines that are extensively used. These drug interactions can have severe consequences and pose a significant challenge to healthcare providers. Therefore, it is crucial to identify the underlying mechanisms of these interactions and develop strategies to minimize medication errors.

AREAS COVERED

We analyzed databases on GI illnesses common in older adults, including GERD, peptic ulcer disease, IBS, IBD, constipation, and diarrhea. Our research identified noteworthy drug interactions and utilized major electronic databases such as USFDA, PubMed, Scopus, and Google Scholar until 15 May 202315 May 2023, along with a review of reference lists.

EXPERT OPINION

Aging can affect how the body processes drugs, leading to an increased risk of drug interactions. Therefore, healthcare professionals must carefully evaluate a patient's medical history and health condition to design personalized treatment plans.

Disease-Drug Interactions Requiring Special Attention

This short review addresses disease-drug interactions requiring special attention, namely interactions between common conditions and over-the-counter medication and interactions between rare conditions and drugs that are absolutely contraindicated. We specifically examine over-the-counter analgesics, antiemetics and drugs used to treat allergy symptoms and underlying disease conditions they can exacerbate. Resources for avoiding disease-drug interactions in patients with rare conditions, such as myasthenia gravis, glucose-6-phosphate deficiency, mitochondriopathies and long QT-syndrome are given. We also discuss methods for avoiding disease-drug interactions in clinical practice. These include awareness, regular diagnosis- and drug-history taking, consulting the product information, good communication between healthcare providers and patient education. Furthermore, pharmacovigilance activities help in the early identification and characterization of adverse drug reactions resulting from disease-drug interactions.

The association between polypharmacy, frailty and disability-free survival in community-dwelling healthy older individuals

OBJECTIVES

Polypharmacy and frailty are two common geriatric conditions. In community-dwelling healthy older adults, we examined whether polypharmacy is associated with frailty and affects disability-free survival (DFS), assessed as a composite of death, dementia, or persistent physical disability.

METHODS

We included 19,114 participants (median age 74.0 years, IQR: 6.1 years) from ASPirin in Reducing Events in the Elderly (ASPREE) clinical trial. Frailty was assessed by a modified Fried phenotype and a deficit accumulation Frailty Index (FI). Polypharmacy was defined as concomitant use of five or more prescription medications. Multinomial logistic regression was used to examine the cross-sectional association between polypharmacy and frailty at base line, and Cox regression to determine the effect of polypharmacy and frailty on DFS over five years.

RESULTS

Individuals with polypharmacy (vs. <5 medications) were 55% more likely to be pre-frail (Relative Risk Ratio or RRR: 1.55; 95%Confidence Interval or CI:1.44, 1.68) and three times more likely to be frail (RRR: 3.34; 95%CI:2.64, 4.22) according to Fried phenotype. Frailty alone was associated with double risk of the composite outcome (Hazard ratio or HR: 2.16; 95%CI: 1.56, 2.99), but frail individuals using polypharmacy had a four-fold risk (HR: 4.24; 95%CI: 3.28, 5.47). Effect sizes were larger when frailty was assessed using the FI.

CONCLUSION

Polypharmacy was significantly associated with pre-frailty and frailty at baseline. Polypharmacy-exposed frailty increased the risk of reducing disability-free survival among older adults. Addressing polypharmacy in older people could ameliorate the impact of frailty on individuals' functional status, cognition and survival.

Newly initiated cardiovascular medication and short-term risk of unintentional poisoning among Swedish middle-aged and older adults: A national register-based case-crossover study

BACKGROUND

Although some studies have shown the average side effects of cardiovascular medication, the short-term effect after newly initiated cardiovascular medications has not been studied in any detail. We aim to determine the effect of newly initiated cardiovascular medications resulting in unintentional poisoning and to identify those at high risk.

METHODS

A case-crossover design was used. From the Swedish National Patient Register, a total of 9,354 persons aged ≥ 50 and hospitalized with a first event of unintentional poisoning between July 2006 and September 2018 were identified. Through linkage to the Prescribed Drug Register, exposure to newly initiated cardiovascular medication during the case period (1-28 days prior to the onset date of unintentional poisoning) was compared with that in a corresponding control period (113-140 days prior to the onset date). Conditional logistic regression was used to determine the associations in total, for different time periods as well as by age, sex, underlying comorbidity, and use of other medications.

RESULTS

Newly initiated cardiovascular medications were associated with a higher risk of unintentional poisoning, especially during the first week after initiation (odds ratio [OR]=1.39), (95% confidence interval [CI]=1.08-1.79). The risk of unintentional poisoning was comparable across age groups, sex, underlying comorbidities, and medications with OR (95% CI) ranging from 1.15 (0.75-1.74) to 2.00 (1.15-3.47).

CONCLUSION

This large population-based case-crossover study showed that newly initiated cardiovascular medication is associated with an increased risk of unintentional poisoning, particularly during the first week after initiation. The risk is comparable across age, sex, underlying comorbidity, and medications.

Drug interactions in hospital prescriptions in Denmark: Prevalence and associations with adverse outcomes

Purpose

While the beneficial effects of medications are numerous, drug–drug interactions may lead to adverse drug reactions that are preventable causes of morbidity and mortality. Our goal was to quantify the prevalence of potential drug–drug interactions in drug prescriptions at Danish hospitals, estimate the risk of adverse outcomes associated with discouraged drug combinations, and highlight the patient types (defined by the primary diagnosis of the admission) that appear to be more affected.

Methods

This cross‐sectional (descriptive part) and cohort study (adverse outcomes part) used hospital electronic health records from two Danish regions (~2.5 million people) from January 2008 through June 2016. We included all inpatients receiving two or more medications during their admission and considered concomitant prescriptions of potentially interacting drugs as per the Danish Drug Interaction Database. We measured the prevalence of potential drug–drug interactions in general and discouraged drug pairs in particular during admissions and associations with adverse outcomes: post‐discharge all‐cause mortality rate, readmission rate and length‐of‐stay.

Results

Among 2 886 227 hospital admissions (945 475 patients; median age 62 years [IQR: 41–74]; 54% female; median number of drugs 7 [IQR: 4–11]), patients in 1 836 170 admissions were exposed to at least one potential drug–drug interaction (659 525 patients; median age 65 years [IQR: 49–77]; 54% female; median number of drugs 9 [IQR: 6–13]) and in 27 605 admissions to a discouraged drug pair (18 192 patients; median age 68 years [IQR: 58–77]; female 46%; median number of drugs 16 [IQR: 11–22]). Meropenem‐valproic acid (HR: 1.5, 95% CI: 1.1–1.9), domperidone‐fluconazole (HR: 2.5, 95% CI: 2.1–3.1), imipramine‐terbinafine (HR: 3.8, 95% CI: 1.2–12), agomelatine‐ciprofloxacin (HR: 2.6, 95% CI: 1.3–5.5), clarithromycin‐quetiapine (HR: 1.7, 95% CI: 1.1–2.7) and piroxicam‐warfarin (HR: 3.4, 95% CI: 1–11.4) were associated with elevated mortality. Confidence interval bounds of pairs associated with readmission were close to 1; length‐of‐stay results were inconclusive.

Conclusions

Well‐described potential drug–drug interactions are still missed and alerts at point of prescription may reduce the risk of harming patients; prescribing clinicians should be alert when using strong inhibitor/inducer drugs (i.e. clarithromycin, valproic acid, terbinafine) and prevalent anticoagulants (i.e. warfarin and non‐steroidal anti‐inflammatory drugs ‐ NSAIDs) due to their great potential for dangerous interactions. The most prominent CYP isoenzyme involved in mortality and readmission rates was 3A4.

Prevalence of drug-drug interactions in older people before and after hospital admission: analysis from the OPERAM trial

Background

Drug-drug interactions (DDIs) are highly prevalent in older patients but little is known about prevalence of DDIs over time. Our main objective was to assess changes in the prevalence and characteristics of drug-drug interactions (DDIs) during a one-year period after hospital admission in older people, and associated risk factors.

Methods

We conducted a sub-study of the European OPERAM trial (OPtimising thERapy to prevent Avoidable hospital admissions in Multimorbid older people), which assessed the effects of a structured medication review (experimental arm) compared to usual care (control arm) on reducing drug-related hospital readmissions. All OPERAM patients (≥70 years, with multimorbidity and polypharmacy, hospitalized in four centers in Bern, Brussels, Cork and Utrecht between December 2016 and October 2018, followed over 1 year) who were alive at hospital discharge and had full medication data during the index hospitalization (at baseline i.e., enrolment at admission, and at discharge) were included. DDIs were assessed using an international consensus list of potentially clinically significant DDIs in older people. The point-prevalence of DDIs was evaluated at baseline, discharge, and at 2, 6 and 12 months after hospitalization. Logistic regression models were performed to assess independent variables associated with changes in DDIs 2 months after baseline.

Results

Of the 1950 patients (median age 79 years) included, 1045 (54%) had at least one potentially clinically significant DDI at baseline; point-prevalence rates were 58, 57, 56 and 57% at discharge, and 2, 6 and 12 months, respectively. The prevalence increased significantly from baseline to discharge (P < .001 [significant only in the control group]), then remained stable over time (P for trend .31). The five most common DDIs –all pharmacodynamic in nature– accounted for 80% of all DDIs and involved drugs that affect potassium concentrations, centrally-acting drugs and antithrombotics. At 2 months, DDIs had increased in 459 (27%) patients and decreased in 331 (19%). The main factor predictive of a change in the prevalence of DDIs was hyperpolypharmacy (≥10 medications).

Conclusions

DDIs were very common; their prevalence increased during hospitalization and tended to remain stable thereafter. Medication review may help control this increase and minimize the risk of adverse drug events.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02532-z.

Prevalence and Factors Associated with Potential Drug-Drug Interactions in Older Community-Dwelling Adults: A Prospective Cohort Study

Background

Older patients are at increased risk of drug-drug interactions (DDIs) due to polypharmacy. Cardiovascular and central nervous system (CNS) drugs are commonly implicated in serious DDIs.

Objectives

This study aimed to determine the prevalence and factors associated with potential ‘severe’ cardiovascular and CNS DDIs among older (≥ 70 years) community-dwellers.

Methods

This was a prospective cohort study using linked data from a national pharmacy claims database and waves 1 and 2 of The Irish LongituDinal study on Ageing (TILDA). ‘Severe’ cardiovascular and CNS DDIs were identified using the British National Formulary 77 and Stockley’s Drug Interactions. The prevalence of ‘severe’ DDIs (any DDI vs. none) was calculated. Logistic regression was used to examine the association between sociodemographic, functional ability, and medication-related factors and the risk of DDI exposure between waves 1 and 2.

Results

A total of 1466 patients were included [mean age (standard deviation) = 78 (5.5) years; female n = 795, 54.2%]. In total, 332 community-dwellers aged ≥ 70 years [22.65%, 95% confidence interval (CI) 20.58–24.86] were potentially exposed to at least one ‘severe’ cardiovascular or CNS DDI, with more than half (54.82%) of this cohort dispensed the same DDI for a prolonged time (≥ 3 consecutive claims). Aspirin-warfarin was the most frequently dispensed (co-prescribed) DDI (n = 34, 10.24%, 95% CI 7.39–14.00), followed by atorvastatin-clarithromycin (n = 19, 5.72%, 95% CI 3.64–8.81). Polypharmacy [≥ 10 vs. < 5 drugs, odds ratio (OR) 13.40, 95% CI 8.22–21.85] and depression (depressed vs. not, OR 2.12, 95% CI 1.34–3.34) were significantly associated with these DDIs, after multivariable adjustment.

Conclusion

‘Severe’ cardiovascular and CNS DDIs are prevalent in older community-dwellers in Ireland, and those with polypharmacy and depression are at a significantly increased risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40266-021-00898-8.

Development and evaluation of a physiologically based pharmacokinetic model to predict carvedilol-paroxetine metabolic drug-drug interaction in healthy adults and its extrapolation to virtual chronic heart failure patients for dose optimization

Purpose: The metabolic drug-drug interactions (mDDIs) are one of the most important challenges faced by the pharmaceutical industry during the drug development stage and are frequently associated with labeling restrictions and withdrawal of drugs. The capacity of physiologically based pharmacokinetic (PBPK) models to absorb and upgrade with the newly available information on drug and population-specific parameters, makes them a preferred choice over the conventional pharmacokinetic models for predicting mDDIs.Method: A PBPK model capable of predicting the stereo-selective disposition of carvedilol after administering paroxetine by incorporating mechanism (time) based inhibition of CYP2D6 and CYP3A4 was developed by using the population-based absorption, distribution, metabolism and elimination (ADME) simulator, Simcyp®.Results: The model predictions for both carvedilol enantiomers were in close agreement with the observed PK data, as the ratios for observed/predicted PK parameters were within the 2-fold error range. The developed PBPK model was successful in capturing an increase in exposures of R and S-carvedilol, due to the time-based inhibition of CYP2D6 enzyme caused by paroxetine.Conclusion: The developed model can be used for exploring complex clinical scenarios, where multiple drugs are given concurrently, particularly in diseased populations where no clinical trial data is available.

An International Consensus List of Potentially Clinically Significant Drug-Drug Interactions in Older People

OBJECTIVES

We aimed to establish an explicit list of potentially clinically significant drug-drug interactions (DDIs) in people aged ≥65 years.

DESIGN

A preliminary list of potentially clinically significant DDIs was compiled, based on 154 DDIs identified from literature review. Subsequently, a 2-round online Delphi survey was undertaken with a multidisciplinary expert panel. A consensus meeting and a final round were conducted to validate the final DDI list and the scope of information provided.

SETTING AND PARTICIPANTS

Twenty nine experts, including geriatricians and clinical pharmacists from 8 European countries.

MEASURES

For each DDI, in the first 2 rounds, experts were asked to score the severity of potential harm on a 5-point Likert-type scale. DDIs were directly included on the final list if the median score was 4 (major) or 5 (catastrophic). DDIs with a median score of 3 (moderate) were discussed at a consensus meeting and included if ≥75% of participants voted for inclusion in the final round.

RESULTS

Consensus was achieved on 66 potentially clinically significant DDIs (28 had a median score of 4/5 and 48 of 3 in the Delphi survey). Most concerned cardiovascular, antithrombotic, and central nervous system drugs. The final list includes information on the mechanism of interaction, harm, and management. Treatment modification is recommended for three-quarters of DDIs.

CONCLUSION AND IMPLICATIONS

We validated a list of potentially clinically significant DDIs in older people, which can be used in clinical practice and education to support identification and management of DDIs or to assess prevalence in epidemiologic and intervention studies.

Factors Associated with Frailty According to Gender of Older Adults Living Alone

This study was conducted to identify the factors associated with frailty according to gender of older adults living alone in Korea. Data from the National Survey of the Living Conditions of Korean Elderly in 2017 were used. Participants were 2340 older adults who live alone. Frailty was determined based on the frailty criteria developed by van Kan et al. that consist of fatigue, resistance, ambulation, and illness. The collected data were analyzed using descriptive statistics, chi-squared test, t-test, Jonckheere–Terpstra test and multinomial logistic regression. Among the older men living alone, 47.7% were in the pre-frail and 5.1% were in the frail. On the other hand, 51.8% were in the pre-frail and 12.2% were in the frail among the older women living alone. The factors associated with frailty according to gender are as follows. In males, depressive symptoms, limitation in IADL, and number of medications in pre-frail; BMI, limitation in IADL, and number of chronic diseases in frail. In females, depressive symptoms, number of chronic diseases, age, and nutritional status in pre-frail; limitation in IADL, depressive symptoms, age, number of chronic diseases, number of medications, nutritional status in frail. Based on the findings of this study, it is considered necessary to approach frailty management considering gender as well as the classification of frailty.

Risk Prediction Method for Anticholinergic Action Using Auto-quantitative Structure-Activity Relationship and Docking Study with Molecular Operating Environment

Lower urinary tract symptoms (LUTS) induced by anticholinergic drug action impair the QOL of patients and are associated with a poor prognosis. Therefore, it is expedient to develop methods of predicting the anticholinergic side effects of drugs, which we aimed to achieve in this study using a quantitative structure-activity relationship (QSAR) and docking study with molecular operations environment (MOE; Molecular Simulation Informatics Systems [MOLSIS], Inc.) In the QSAR simulation, the QSAR model built using the partial least squares regression (PLS) and genetic algorithm-multiple linear regression (GA-MLR) methods showed remarkable coefficient of determination (R²) and XR² values. In the docking study, a specific relationship was identified between the adjusted docking score (-S) and bioactivity (pKi) values. In conclusion, the methods developed could be useful for in silico risk assessment of LUTS, and plans are potentially applicable to numerous drugs with anticholinergic activity that induce serious side effects, limiting their use.

The Prevalence and Characteristics of Psychotropic-Related Hospitalizations in Older People: A Systematic Review and Meta-Analysis

OBJECTIVES

To assess the prevalence and characteristics of psychotropic medication-related hospitalizations in older people.

DESIGN

Systematic review with meta-analysis.

SETTING AND PARTICIPANTS

Older adults (≥65 years of age) with psychotropic-related hospitalizations.

METHODS

A search of published literature was performed in Medline, Embase, CINAHL, and Scopus from 2010 to March 2020. Three authors independently screened titles, abstracts, and full texts of relevant studies for relevance. Two authors independently extracted full text data, including characteristics, measures of causality, prevalence data, and performed quality assessment. A meta-analysis was conducted to estimate pooled prevalence and 95% confidence intervals (CIs) of psychotropic-related hospitalizations using random effects models. Heterogeneity was explored using subgroup analyses.

RESULTS

Of 815 potentially relevant studies, 11 were included in the final analysis. Five studies were cross-sectional studies, 5 were cohort studies, and 1 was a case control study. The majority of studies were rated as good quality. Psychotropic medications contributed to 2.1% (95% CI 1.2%-3.3%) of total hospitalizations and 11.3% (95% CI 8.2%-14.8%) of adverse drug event-related hospitalizations. The main psychotropic medications attributable to hospitalizations were antidepressants, hypnotics, sedatives, and antipsychotics.

CONCLUSIONS AND IMPLICATIONS

Psychotropic medications are a significant contributor to hospitalizations in older adults. The risk of hospitalization was greatest for those taking antidepressants, antipsychotics, hypnotics, and sedatives. Future studies should aim to address specific medication subgroups and implement uniform adverse drug event-related classification systems to improve comparability across studies.

Medication Use Quality and Safety in Older Adults: 2019 Update

Improving the quality of medication use and medication safety are important priorities for prescribers who care for older adults. The objective of this article was to identify four exemplary articles with this focus in 2019. We selected high-quality studies that moved the field of research forward and were not merely replication studies. The chosen articles cover domains related to aspects of suboptimal prescribing and medication safety. The first study used a nationally representative sample of Medicare beneficiaries to examine the continuation of medications with limited benefit in patients admitted for cancer and non-cancer diagnoses in hospice (domain: potentially inappropriate medications). The second study, a retrospective cohort study of older adults in Ontario, Canada, assessed the association between prescribing oral anticoagulants in an emergency department relative to not prescribing anticoagulants in the emergency department and their persistence at 6 months (domain: underuse of medications). The third study, a cluster randomized trial in Quebec, Canada, evaluated the effect of conducting electronic medication reconciliation on several outcomes including adverse drug events and medication discrepancies (domain: medication safety). Lastly, the fourth study, a retrospective study using national inpatient and outpatient Veteran Health Administration combined with clinical and Medicare Claims data, examined the effects of intensification of antihypertensive medications on older adults' likelihood for hospital re-admission and other important clinical outcomes (domain: medication safety). Collectively, this review succinctly highlights pertinent topics related to promoting safe use of medications and promotes awareness of optimizing older adults' medication regimens.

Development, validation and performance of a newly designed tool to evaluate functional medication literacy in Slovenia

Background Medication literacy refers to the ability of individuals to safely and appropriately access, understand and act on basic medication information. It is vital for correctly and safely using medications. General health literacy measures do not adequately address specific skills for medication literacy, and there are no general, self-administered, performance-based instruments for assessing patients' medication literacy. Objective The aim was to develop and validate a self-administered performance-based questionnaire measuring functional medication literacy and to evaluate functional medication literacy among the Slovenian general population. Setting A random sample of adult Slovenian residents received the questionnaires at their home addresses. Method The initial content was derived from medication counselling literature. Thirteen patients and 14 healthcare professionals provided feedback about its comprehensibility, comprehensiveness, and difficulty thus supporting content and face validity. The developed questionnaire, comprising 30 items divided into 5 categories (dosage, adverse effects, interactions, precautions, and other information), was sent to a random sample of 1500 adult Slovenian residents. The overall validity of the questionnaire was assessed via reliability, criterion and discriminant validity using the Kuder-Richardson Formula 20, multiple linear regression and Mann-Whitney test. Descriptive statistics were used to evaluate medication literacy. Main outcome measure The psychometric properties of the questionnaire (reliability, content, face, criterion, and discriminant validity); level of functional medication literacy. Results A total of 402 residents returned eligible questionnaires (26.8% response rate). The Kuder-Richardson Formula 20 reliability coefficient for the whole questionnaire was 0.823. One item that did not demonstrate discriminant validity was deleted. Criterion validity was supported by a significant association between age and medication literacy (β = - 0.303). Income (β = 0.243) and current self-perceived health (β = 0.187) also were associated with medication literacy. The median of medication literacy score was 24 out of 29 points. Dosage-related items requiring understanding of long text instructions and the use of numeracy skills received the most incorrect answers. Conclusion A performance-based questionnaire measuring functional medication literacy among a general population with supported validity was developed. Slovenian residents encountered difficulties when dealing with items requiring prose literacy and numeracy skills, especially related to dosing. Special attention should be paid to low-income elderly with poor self-perceived health.

Drug-disease interactions in Swedish senior primary care patients were dominated by non-steroid anti-inflammatory drugs and hypertension - a population-based registry study

OBJECTIVE

Drug-disease interactions (DDSIs) are present when a drug prescribed for one disease worsens a concomitant disease. The prevalence of DDSIs in older patients in primary care is largely unknown, as well as to what extent physicians individualize drug prescribing in relation to concomitant diseases. We therefore analysed the prevalence of DDSIs in older patients in primary care and explored to what extent physicians take possible DDSIs into account when prescribing. Design and Setting: Cross-sectional population-based register study in primary care in Region Stockholm, Sweden. Thirty-one DDSIs derived from Irish STOPP-START-Criteria were assessed. We derived data from a regional administrative healthcare database including information on all healthcare consultations and dispensed prescription drugs in the region. Data on demography, diagnoses, drug dispensations and healthcare consumption were extracted. Drugs were assessed during 2016.

SUBJECTS

A total of 336,295 patients aged ≥65 registered with one of the 206 primary care practices in Region Stockholm.

MAIN OUTCOME MEASURES

Prevalence and prevalence differences for DDSIs.

RESULTS

In 10.8% of older patients, at least one DDSI was observed. Non-steroidal anti-inflammatory drugs (NSAIDs) were implicated in more than 75% of cases. The most common DDSI was NSAID/hypertension (8.1%), followed by NSAID/cardiovascular disease and loop diuretics/urinary incontinence (both 0.7%). The use of NSAIDs among patients with heart failure or impaired renal function was 15% lower than among patients without these diseases.

CONCLUSION

DDSIs were present in every tenth older patient in primary care. Patients with cardiovascular disease receive NSAIDs to a lower extent, possibly indicating physician awareness of DDSI. Key points Evidence on the prevalence of drug-disease interactions in older patients in primary care is sparse despite their potential to cause harm. In this study, we found that every 10th older patient attending primary care had at least one drug-disease interaction. Interactions with NSAIDs were far more common than interactions with other drugs. The use of NSAIDs among patients with heart failure or impaired renal function was 15% lower than among patients without these diseases.

Cytochrome P450-mediated drug interactions in COVID-19 patients: Current findings and possible mechanisms

At the end of 2019, the entire world has witnessed the birth of a new member of coronavirus family in Wuhan, China. Ever since, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has swiftly invaded every corner on the planet. By the end of April 2020, almost 3.5 million cases have been reported worldwide, with a death toll of about 250,000 deaths. It is currently well-recognized that patient’s immune response plays a pivotal role in the pathogenesis of Coronavirus Disease 2019 (COVID-19). This inflammatory element was evidenced by its elevated mediators that, in severe cases, reach their peak in a cytokine storm. Together with the reported markers of liver injury, such hyperinflammatory state may trigger significant derangements in hepatic cytochrome P450 metabolic machinery, and subsequent modulation of drug clearance that may result in unexpected therapeutic/toxic response. We hypothesize that COVID-19 patients are potentially vulnerable to a significant disease-drug interaction, and therefore, suitable dosing guidelines with therapeutic drug monitoring should be implemented to assure optimal clinical outcomes.

Medicamentos potencialmente inapropriados prescritos a pacientes de um Centro de Referência em Atenção à Saúde da Pessoa Idosa

Resumo Objetivo Analisar o perfil farmacoterapêutico dos idosos atendidos em um Centro de Referência em Atenção à Saúde da Pessoa Idosa quanto ao uso de medicamentos potencialmente inapropriados (MPI) por meio de três critérios de rastreamento e determinar fatores associados à prescrição de MPI. Método Estudo transversal com dados obtidos por revisão retrospectiva dos prontuários de idosos, atendidos entre 2017 e 2018 por médico geriatra. Para identificar os MPI, utilizaram-se os Critérios de Beers, o Screening Tool of Older Persons’ Potentially Inappropriate Prescriptions (STOPP) e o Consenso Brasileiro de Medicamentos Potencialmente Inapropriados para Idosos. Características relacionadas ao perfil sociodemográfico (idade e sexo), de hábitos de vida (tabagismo e consumo de álcool), clínico (doenças) e farmacoterapêutico (medicamentos e Índice de Complexidade da Farmacoterapia - ICFT) foram avaliadas. Resultados Foram analisados 406 prontuários e identificados 3.059 medicamentos prescritos, dos quais 32,1% são MPI segundo Critérios STOPP, 14,4% pelo Consenso Brasileiro e 11,7% pelos Critérios de Beers. No total, 81,1% dos idosos apresentaram ao menos um MPI. Regressão de Poisson demonstrou associação entre a prescrição de MPI com polifarmácia, maior número de sinais e sintomas e maior valor de ICFT em ao menos um dos critérios. A força de concordância entre os critérios de MPI foi moderada. Conclusões A maioria dos prontuários analisados possuíam ao menos um MPI prescrito, sendo que os Critérios STOPP identificaram uma maior quantidade de MPI. Estratégias devem ser implementadas para melhorar a farmacoterapia dos idosos com atenção para os que apresentam fatores associados a MPI em seu perfil.

Onco-cardiology: Drug-drug interactions of antineoplastic and cardiovascular drugs

Cardiovascular diseases (CVD) and cancer are still the leading causes of death. There are many common etiologic factors, especially smoking and obesity. Therefore, it is not uncommon for CVD and cancer to coexist. Drug-drug interactions (DDIs) inevitably occur in this group of patients, where polypharmacy is increasing due to older age and multiple comorbidities. However, multidisciplinary studies, especially close collaboration of medical oncologists and cardiologists, who deals with the diagnosis and treatment of these diseases, awareness and preventive approaches to DDIs may reduce serious morbidity and mortality. In this review, information about the common treatments used in cardiology and oncology and possible DDIs are discussed.

Influence of pharmacist intervention on drug safety of geriatric inpatients: a prospective, controlled trial

BACKGROUND

Demographic shift leads to an increasing number of geriatric patients suffering from multimorbidity and resulting polypharmacy. Polypharmacy is shown to be associated with drug-related problems (DRPs) and increased morbidity. For Germany, a hospital-based intervention may be successful optimizing of polypharmacy. The aim of this study was to reduce DRPs in geriatric inpatients by a structured pharmacist's intervention and to measure the acceptance rate of pharmaceutical recommendations.

METHODS

This study followed an open, prospective, quasi-randomized, controlled design and was conducted in a geriatric department in a teaching hospital in Germany. Patients of all sexes were included, with a minimum age of 70 years, a written informed consent and a regular intake of at least five drugs daily. Primary outcome was the percentage of patients having a DRP at admission and discharge. A DRP was defined as a prescription without indication or a relevant drug-drug interaction or prescription of a potentially inappropriate medication or presence of an adverse drug reaction. Recommendations were classified and discussed face to face. Statistical analyses were performed using a full-set analysis and a matched-pairs design.

RESULTS

Within 12 months, 411 patients were recruited with median age of 82 years (intervention: n = 209; control: n = 202). Median number of drugs at admission was 10 (range 5-24), at discharge 9 (range 3-21). In the intervention group, the percentage of patients with a DRP was reduced from 86.6% to 56.0%; in the control group, from 76.7% to 76.2% (p value < 0.001). Medication appropriateness index score was reduced by 56% in the intervention group and by 0.2% in the control group (p value < 0.001). Implementation rate of the pharmaceutical recommendation was 80%.

CONCLUSION

This prospective controlled trial showed that a pharmacist's intervention was successful in optimizing polypharmacy in geriatric inpatients.

Interactions between drugs and geriatric syndromes in nursing home and home care: results from Shelter and IBenC projects

AIM

Drugs may interact with geriatric syndromes by playing a role in the continuation, recurrence or worsening of these conditions. Aim of this study is to assess the prevalence of interactions between drugs and three common geriatric syndromes (delirium, falls and urinary incontinence) among older adults in nursing home and home care in Europe.

METHODS

We performed a cross-sectional multicenter study among 4023 nursing home residents participating in the Services and Health for Elderly in Long-TERm care (Shelter) project and 1469 home care patients participating in the Identifying best practices for care-dependent elderly by Benchmarking Costs and outcomes of community care (IBenC) project. Exposure to interactions between drugs and geriatric syndromes was assessed by 2015 Beers criteria.

RESULTS

790/4023 (19.6%) residents in the Shelter Project and 179/1469 (12.2%) home care patients in the IBenC Project presented with one or more drug interactions with geriatric syndromes. In the Shelter project, 288/373 (77.2%) residents experiencing a fall, 429/659 (65.1%) presenting with delirium and 180/2765 (6.5%) with urinary incontinence were on one or more interacting drugs. In the IBenC project, 78/172 (45.3%) participants experiencing a fall, 80/182 (44.0%) presenting with delirium and 36/504 (7.1%) with urinary incontinence were on one or more interacting drugs.

CONCLUSION

Drug-geriatric syndromes interactions are common in long-term care patients. Future studies and interventions aimed at improving pharmacological prescription in the long-term care setting should assess not only drug-drug and drug-disease interactions, but also interactions involving geriatric syndromes.

Analysis of Drug-Drug Interactions in Swiss Claims Data Using Tizanidine and Ciprofloxacin as a Prototypical Contraindicated Combination

BACKGROUND

Potential drug-drug interactions (pDDIs) are described in various case reports, but few studies have evaluated the impact of specific combinations on a population level.

OBJECTIVE

To analyze the type and frequency of multiple contraindicated (X-pDDIs) and major interactions (D-pDDIs) and to subsequently assess the impact of the particular combination of tizanidine and ciprofloxacin on outpatient physician visits and hospitalizations.

METHODS

Anonymized Swiss claims data from 524 797 patients in 2014-2015 were analyzed. First, frequencies of X- and D-pDDIs were calculated. Next, a retrospective cohort study was conducted among patients prescribed tizanidine and ciprofloxacin (exposed, n = 199) or tizanidine and other antibiotics (unexposed, n = 960). Hospitalizations and outpatient physician visits within 7, 14, and 30 days after initiation of antibiotic therapy were evaluated using multiple binary logistic regression and multiple linear regression.

RESULTS

The relative frequencies of X- and D-pDDIs were 0.4% and 6.65%, respectively. In the cohort study, significant associations between exposure to tizanidine and ciprofloxacin and outpatient physician visits were identified for 14 and 30 days (odds ratio [OR] = 1.61 [95% CI = 1.17-2.24], P = 0.004, and OR = 1.59 [95% CI = 1.1-2.34], P = 0.016). A trend for increased risk of hospitalization was found for all evaluated time periods (OR = 1.68 [95% CI = 0.84-3.17], OR = 1.52 [95% CI = 0.63-3.33], and OR = 2.19 [95% CI = 0.88-5.02]). Conclusion and Relevance: The interaction between tizanidine and ciprofloxacin is not only relevant for individual patients, but also at the population level. Further investigation of the impact of other clinically relevant DDIs is necessary to improve patient safety and reduce avoidable health care utilization.

Drug-drug interactions and their harmful effects in hospitalised patients: a systematic review and meta-analysis

PURPOSE

Drug-drug interactions (DDIs) are often avoidable and, if undetected, can lead to patient harm. This review aimed to determine the prevalence of potential DDIs (pDDIs), clinically relevant DDIs (DDIs that could lead to measurable patient harm, taking into account the patient's individual clinical profile) and DDIs that resulted in actual patient harm during hospitalisation.

METHOD

Four databases were scanned for English papers published from 2000 to 2016. Papers that reported prevalence of DDIs in the outpatient setting, at admission or discharge, involving only specific drugs, or in specific disease populations or age groups were excluded.

RESULTS

Twenty-seven papers met the inclusion criteria and were graded for quality using the Critical Appraisal Skills Programme (CASP) cohort study checklist. Ten papers were rated as 'poor', 14 as 'fair' and only three papers as 'good'. Overall, the meta-analysis revealed that 33% of general patients and 67% of intensive care patients experienced a pDDI during their hospital stay. It was not possible to determine the prevalence of clinically relevant DDIs or DDIs that resulted in actual patient harm as data on these categories were limited. Of the very few studies that reported on harm, only a small proportion of DDIs were found to have resulted in actual patient harm.

CONCLUSIONS

Standardisation of DDI definitions and research methods are required to allow meaningful prevalence rates to be obtained and compared. Studies that go further than measuring pDDIs are critically needed to determine the impact of DDIs on patient safety.

Oleanolic Acid-Mediated Inhibition of Pregnane X Receptor and Constitutive Androstane Receptor Attenuates Rifampin-Isoniazid Cytotoxicity

Interactions between transcriptional inducers of cytochrome P450 (CYP450) and pharmacological agents might decrease drug efficacy and induce side effects. Such interactions could be prevented using an antagonist of the pregnane X receptor (PXR) and constitutive androstane receptor (CAR). Here, we aimed to determine the antagonistic effect of oleanolic acid (OA) on PXR and CAR. OA attenuated the promoter activities, expressions, and enzyme catalytic activities of CYP3A4 and CYP2B6 mediated by rifampin (RIF) and CITCO. Moreover, OA displayed species specificity for rodent PXR. Interaction of coregulators with PXR and transcriptional complexes on the CYP3A4 promoter was disrupted by OA. Additionally, OA reversed the cytotoxic effects of isoniazid induced by RIF. These data demonstrate that OA inhibited the transactivation of PXR and CAR, reduced the expression and function of CYP3A4 and CYP2B6, and may therefore serve as an effective agent for reducing probability adverse interactions between transcriptional inducers of CYP450 and therapeutic drugs.

Impact of Drug-Drug and Drug-Disease Interactions on Gait Speed in Community-Dwelling Older Adults

BACKGROUND

Gait speed decline, an early marker of functional impairment, is a sensitive predictor of adverse health outcomes in older adults. The effect of potentially inappropriate medications, including drug-disease and drug-drug interactions, on gait speed decline is not well known.

OBJECTIVE

The aim of this study was to determine if drug interactions impair functional status as measured by gait speed.

METHODS

The sample included 2402 older adults with medication and gait speed data from the Health, Aging and Body Composition study. The independent variable was the frequency of drug-disease and/or drug-drug interactions at baseline and 3 additional years. The main outcome was a clinically meaningful gait speed decline of ≥0.1 m/s the year following drug interaction assessment. Adjusted odds ratios and 95 % confidence intervals (CIs) were calculated using multivariate generalized estimating equations for both the overall sample and a sample stratified by gait speed at time of drug interaction assessment.

RESULTS

The prevalence of drug-disease and drug-drug interactions ranged from 7.6 to 9.3 and 10.5 to 12.3 %, respectively, with few participants (3.8-5.7 %) having multiple drug interactions. At least 22 % of participants had a gait speed decline of ≥0.1 m/s annually. Drug interactions were not significantly associated with gait speed decline overall or in the stratified sample of fast walkers. There was some evidence, however, that drug interactions increased the risk of gait speed decline among those participants with slower gait speeds, though p values did not reach statistical significance (adjusted odds ratio 1.22; 95 % CIs 0.96-1.56; p = 0.11). Moreover, a marginally significant dose-response relationship was seen with multiple drug interactions and gait speed decline (adjusted odds ratio 1.40; 95 % CIs 0.95-2.04; p = 0.08).

CONCLUSIONS

Drug interactions may increase the likelihood of gait speed decline among older adults with evidence of preexisting debility. Future studies should focus on frail elders with less physiological reserve who may be more susceptible to the harms associated with potentially inappropriate medications.

Clinically relevant potential drug-drug interactions among outpatients: A nationwide database study

BACKGROUND

Adverse drug events due to drug-drug interactions (DDIs) represent a considerable public health burden, also in Slovenia. A better understanding of the most frequently occurring potential DDIs may enable safer pharmacotherapy and minimize drug-related problems.

OBJECTIVES

The aim of this study was to evaluate the prevalence and predictors of potential DDIs among outpatients in Slovenia.

METHODS

An analysis of potential DDIs was performed using health claims data on prescription drugs from a nationwide database. The Lexi-Interact Module was used as the reference source of interactions. The influence of patient-specific predictors on the risk of potential clinically relevant DDIs was evaluated using logistic regression model.

RESULTS

The study population included 1,179,803 outpatients who received 15,811,979 prescriptions. The total number of potential DDI cases identified was 3,974,994, of which 15.6% were potentially clinically relevant. Altogether, 9.3% (N = 191,213) of the total population in Slovenia is exposed to clinically relevant potential DDIs, and the proportion is higher among women and the elderly. After adjustment for cofactors, higher number of medications and older age are associated with higher odds of clinically relevant potential DDIs. The burden of DDIs is highest with drug combinations that increase risk of bleeding, enhance CNS depression or anticholinergic effects or cause cardiovascular complications.

CONCLUSION

The current study revealed that 1 in 10 individuals in the total Slovenian population is exposed to clinically relevant potential DDIs yearly. Taking into account the literature based conservative estimate that approximately 1% of potential DDIs result in negative health outcomes, roughly 1800 individuals in Slovenia experience an adverse health outcome each year as a result of clinically relevant potential interactions alone.

Potential drug-drug and drug-disease interactions in well-functioning community-dwelling older adults

WHAT IS KNOWN AND OBJECTIVE

There are few studies examining both drug-drug and drug-disease interactions in older adults. Therefore, the objective of this study was to describe the prevalence of potential drug-drug and drug-disease interactions and associated factors in community-dwelling older adults.

METHODS

This cross-sectional study included 3055 adults aged 70-79 without mobility limitations at their baseline visit in the Health Aging and Body Composition Study conducted in the communities of Pittsburgh PA and Memphis TN, USA. The outcome factors were potential drug-drug and drug-disease interactions as per the application of explicit criteria drawn from a number of sources to self-reported prescription and non-prescription medication use.

RESULTS

Over one-third of participants had at least one type of interaction. Approximately one quarter (25·1%) had evidence of had one or more drug-drug interactions. Nearly 10·7% of the participants had a drug-drug interaction that involved a non-prescription medication. % The most common drug-drug interaction was non-steroidal anti-inflammatory drugs (NSAIDs) affecting antihypertensives. Additionally, 16·0% had a potential drug-disease interaction with 3·7% participants having one involving non-prescription medications. The most common drug-disease interaction was aspirin/NSAID use in those with history of peptic ulcer disease without gastroprotection. Over one-third (34·0%) had at least one type of drug interaction. Each prescription medication increased the odds of having at least one type of drug interaction by 35-40% [drug-drug interaction adjusted odds ratio (AOR) = 1·35, 95% confidence interval (CI) = 1·27-1·42; drug-disease interaction AOR = 1·30; CI = 1·21-1·40; and both AOR = 1·45; CI = 1·34-1·57]. A prior hospitalization increased the odds of having at least one type of drug interaction by 49-84% compared with those not hospitalized (drug-drug interaction AOR = 1·49, 95% CI = 1·11-2·01; drug-disease interaction AOR = 1·69, CI = 1·15-2·49; and both AOR = 1·84, CI = 1·20-2·84).

WHAT IS NEW AND CONCLUSION

Drug interactions are common among community-dwelling older adults and are associated with the number of medications and hospitalization in the previous year. Longitudinal studies are needed to evaluate the impact of drug interactions on health-related outcomes.

Is Polypharmacy Associated with Frailty in Older People? Results From the ESTHER Cohort Study

OBJECTIVES

To investigate the relationship between polypharmacy and frailty.

DESIGN

Longitudinal, observational cohort study.

SETTING

Saarland, Germany.

PARTICIPANTS

3,058 community-dwelling adults aged between 57 and 84 years.

MEASUREMENTS

Frailty was assessed according to the frailty phenotype, described by Fried et al. Polypharmacy and hyperpolypharmacy were defined as the concomitant use of five or more and 10 or more drugs, respectively. We assessed associations between polypharmacy and prevalent and incident frailty within 3 years of follow-up by logistic regression models controlled for multiple potential confounders including comorbidity. Additionally, cubic splines were used to assess dose-response associations.

RESULTS

Polypharmacy was reported in 39.1% (n = 1,194), and hyperpolypharmacy in 8.9% (n = 273) of participants. Prevalent frailty was present in 271 (8.9%) participants; 186 (9.3%) of 1,998 non-frail participants with follow-up data became frail within 3 years. After adjustment, polypharmacy and hyperpolypharmacy were associated with prevalent frailty with adjusted odds ratios (95% confidence interval) of 2.30 (1.60-3.31) and 4.97 (2.97-8.32), respectively. Polypharmacy (odds ratio (OR) 1.51 (1.05-2.16)) and hyperpolypharmacy (OR 1.90 (1.10-3.28)) were also independent predictors of incident frailty. Furthermore, there was a moderate exposure-response relationship between the number of medicines and prevalent as well as incident frailty.

CONCLUSION

Our study showed that polypharmacy is associated with frailty. Further research should address the potential benefit of reducing of inappropriate polypharmacy and better pharmacotherapeutic management for preventing medication-associated frailty.

Effects of Changes in Number of Medications and Drug Burden Index Exposure on Transitions Between Frailty States and Death: The Concord Health and Ageing in Men Project Cohort Study

OBJECTIVES

To investigate the effects of number of medications and Drug Burden Index (DBI) on transitions between frailty stages and death in community-dwelling older men.

DESIGN

Cohort study.

SETTING

Sydney, Australia.

PARTICIPANTS

Community-dwelling men aged 70 and older (N=1,705).

MEASUREMENTS

Self-reported questionnaires and clinic visits were conducted at baseline and 2 and 5 years. Frailty was assessed at all three waves according to the modified Fried frailty phenotype. The total number of regular prescription medications and DBI (a measure of exposure to sedative and anticholinergic medications) were calculated over the three waves. Data on mortality over 9 years were obtained. Multistate modeling was used to characterize the transitions across three frailty states (robust, prefrail, frail) and death.

RESULTS

Each additional medication was associated with a 22% greater risk of transitioning from the robust state to death (adjusted 95% confidence interval (CI)=1.06-1.41). Every unit increase in DBI was associated with a 73% greater risk of transitioning from the robust state to the prefrail state (adjusted 95% CI=1.30-2.31) and a 2.75 times greater risk of transitioning from the robust state to death (adjusted 95% CI=1.60-4.75). There was no evidence of an adjusted association between total number of medications or DBI and the other transitions.

CONCLUSION

Although the possibility of confounding by indication cannot be excluded, additional medications were associated with greater risk of mortality in robust community-dwelling older men. Greater DBI was also associated with greater risk of death and transitioning from the robust state to the prefrail state.

Prevalence of Potential and Clinically Relevant Statin-Drug Interactions in Frail and Robust Older Inpatients

BACKGROUND

A significant proportion of older people are prescribed statins and are also exposed to polypharmacy, placing them at increased risk of statin-drug interactions.

OBJECTIVE

To describe the prevalence rates of potential and clinically relevant statin-drug interactions in older inpatients according to frailty status.

METHODS

A cross-sectional study of patients aged ≥65 years who were prescribed a statin and were admitted to a teaching hospital between 30 July and 10 October 2014 in Sydney, Australia, was conducted. Data on socio-demographics, comorbidities and medications were collected using a standardized questionnaire. Potential statin-drug interactions were defined if listed in the Australian Medicines Handbook and three international drug information sources: the British National Formulary, Drug Interaction Facts and Drug-Reax(®). Clinically relevant statin-drug interactions were defined as interactions with the highest severity rating in at least two of the three international drug information sources. Frailty was assessed using the Reported Edmonton Frail Scale.

RESULTS

A total of 180 participants were recruited (median age 78 years, interquartile range 14), 35.0% frail and 65.0% robust. Potential statin-drug interactions were identified in 10% of participants, 12.7% of frail participants and 8.5% of robust participants. Clinically relevant statin-drug interactions were identified in 7.8% of participants, 9.5% of frail participants and 6.8% of robust participants. Depending on the drug information source used, the prevalence rates of potential and clinically relevant statin-drug interactions ranged between 14.4 and 35.6% and between 14.4 and 20.6%, respectively.

CONCLUSION

In our study of frail and robust older inpatients taking statins, the overall prevalence of potential statin-drug interactions was low and varied significantly according to the drug information source used.

A Delphi process to address medication appropriateness for older persons with multiple chronic conditions

Background

Frameworks exist to evaluate the appropriateness of medication regimens for older patients with multiple medical conditions (MCCs). Less is known about how to translate the concepts of the frameworks into specific strategies to identify and remediate inappropriate regimens.

Methods

Modified Delphi method involving iterative rounds of input from panel members. Panelists (n = 9) represented the disciplines of nursing, medicine and pharmacy. Included among the physicians were two geriatricians, one general internist, one family practitioner, one cardiologist and two nephrologists. They participated in 3 rounds of web-based anonymous surveys.

Results

The panel reached consensus on a set of markers to identify problems with medication regimens, including patient/caregiver report of non-adherence, medication complexity, cognitive impairment, medications identified by expert opinion as inappropriate for older persons, excessively tight blood sugar and blood pressure control among persons with diabetes mellitus, patient/caregiver report of adverse medication effects or medications not achieving desired outcomes, and total number of medications. The panel also reached consensus on approaches to address these problems, including endorsement of strategies to discontinue medications with known benefit if necessary because of problems with feasibility or lack of alignment with patient goals.

Conclusions

The results of the Delphi process provide the basis for an algorithm to improve medication regimens among older persons with MCCs. The algorithm will require assessment not only of medications and diagnoses but also cognition and social support, and it will support discontinuation of medications both when risks outweigh benefits and when regimens are not feasible or do not align with goals.

National indicators for quality of drug therapy in older persons: the Swedish experience from the first 10 years

Inappropriate drug use is an important health problem in elderly persons. Beginning with the Beers’ criteria in the early 1990s, explicit criteria have been extensively used to measure and improve quality of drug use in older people. This article describes the Swedish indicators for quality of drug therapy in the elderly, introduced in 2004 and updated in 2010. These indicators were designed to be applied to people aged 75 years and over, regardless of residence and other characteristics. The indicators are divided into drug specific, covering choice, indication and dosage of drugs, polypharmacy, drug–drug interactions (DDIs), drug use in decreased renal function and in some symptoms; and diagnosis specific, covering the rational, irrational and hazardous drug use in common disorders in elderly people. During the 10 years since introduction, the Swedish indicators have several applications. They form the basis for recommendations for drug therapy in older people, are implemented in prescribing supports and drug utilisation reviews, are used in national benchmarking of the quality of Swedish healthcare and have contributed to initiatives from pensioner organisations. The indicators have also been used in several pharmacoepidemiological studies. Since 2005, there have been signs of improvement of the quality of drug prescribing to elderly persons in Sweden. For example, the prescribing of drugs that should be avoided in older persons decreased by 36 % between 2006 and 2012 in persons aged 80 years and older. Similarly, drug combinations that may cause DDIs decreased by 26 % and antipsychotics by 41 %. The indicators have likely contributed to this.

Prevalence of statin-drug interactions in older people: a systematic review

PURPOSE

Statins are among the most frequently prescribed medications internationally. Older people are commonly prescribed multiple medications and are at an increased risk of drug-drug interactions, including statin-drug interactions. The aim of this study was to conduct a systematic review of current evidence on the prevalence of statin-drug interactions in older people.

METHODS

A systematic search of observational studies in Embase, Medline, and PubMed was conducted. Articles were included if they were published in English during the period July 2000-July 2014 and reported on the prevalence of statin-drug interactions in people over 65 years of age. Two reviewers independently assessed the articles for eligibility and extracted the data.

RESULTS

The search returned 1556 eligible articles. A total of 19 articles met the inclusion criteria. In studies (n = 7) that focused on statin users only, the prevalence of potential statin-drug interactions assessed using different measures ranged from 0.19 to 33.0 %. In studies that examined drug interactions across a population of both statin users and non-users (n = 12), the prevalence of potential statin-drug interactions ranged from 0.1 to 7.1 % (n = 8), and the prevalence of clinically relevant statin-drug interactions ranged from 1.5 to 4 % (n = 4).

CONCLUSIONS

Current published evidence suggests substantial variations in the prevalence of statin-drug interactions and their clinical relevance. Further studies are necessary to provide a better understanding of the prevalence of clinically significant statin-drug interactions, the medications most frequently contributing to statin-drug interactions, and impact on relevant clinical outcomes in older people.

Statin utilisation patterns in older Australians living in residential care: 1-year prevalence study

Despite controversy over the risks and benefits of statin therapy, statins continue to be commonly used medicines by older people. In a cohort study of participants aged ≥70 years (n = 540) living in residential care, Sydney, we found that the proportion of statin users decreased gradually from the baseline of 33.1% to 31.3% at 6 months (P = 0.13) and to 28.7% over 1 year (P = 0.002). Prevalence of statin use decreased with increasing age, with individuals aged ≥90 years being more likely to discontinue or deprescribe statins. The patterns of statin use did not change according to increasing baseline dose or baseline indication.

Prescription rate of medications potentially contributing to lower urinary tract symptoms and detection of adverse reactions by prescription sequence symmetry analysis

Background

The lower urinary tract symptoms (LUTS) increases with age and can have a significant effect on the quality of life of the patients. Elderly patients, who are often characterized by a decline in physiological functional and polypharmacy, are susceptible to adverse drug reactions to pharmacotherapy. LUTS can also be a side effect of medication. The purpose of this study was to investigate the possible association between the initiation of LUTS-causing drug therapy and the onset of LUTS.

Methods

Drug dispensing data at the individual level were retrieved from the CISA (Platform for Clinical Information Statistical Analysis: http://www.cisa.jp) database. A retrospective study was conducted by reviewing patients with LUTS who were dispensed drugs that increased the risk of LUTS between April 2011 and March 2012. Prescription sequence symmetry analysis (PSSA) was employed to investigate the associations between the dispensing of medicines of LUTS and that of LUTS-causing drugs.

Results

LUTS-causing drugs were frequently dispensed to patients with LUTS. The use of medications potentially contributing to LUTS was associated with polypharmacy [number of prescription drugs:12.13 ± 6.78 (user) vs. 5.67 ± 5.24 (nonuser)] but not patient age [ age: (71.38 ± 13.28 (user) vs. 70.45 ± 14.80 (nonuser)]. Significant adverse drug events were observed the use of donepezil, cyclophosphamide, antiparkinson drugs, antidepressant, diazepam, antipsychotic drugs for peptic ulcer, tiotropium bromide, and opioids.

Conclusions

The use of prescription LUTS-causing drugs was correlated with polypharmacy. The adverse drug events associated with LUTS-causing drugs were highly prevalent in elderly patients. To prevent of adverse drug events in patients with LUTS, pharmacists and physicians should regularly review medication lists and reduce the prescribed medicines.

Electronic supplementary material

The online version of this article (doi:10.1186/s40780-014-0004-1) contains supplementary material, which is available to authorized users.

Epidemiology of drug-disease interactions in older veteran nursing home residents

OBJECTIVES

To describe the prevalence of and factors associated with drug-disease interactions (DDIs) in older nursing home residents according to the American Geriatrics Society 2012 Beers Criteria.

DESIGN

Cross-sectional.

SETTING

Fifteen Veterans Affairs Community Living Centers.

PARTICIPANTS

Individuals aged 65 and older with a diagnosis of dementia or cognitive impairment, a history of falls or hip fracture, heart failure (HF), a history of peptic ulcer disease (PUD), or Stage IV or V chronic kidney disease (CKD).

MEASUREMENTS

Medications that could exacerbate the above conditions (DDIs).

RESULTS

Three hundred sixty-one of 696 (51.9%) eligible residents had one or more DDIs. None involved residents with a history of PUD, one involved a resident with CKD, and four occurred in residents with HF. Of 540 residents with dementia or cognitive impairment, 50.7% took a drug that could exacerbate these conditions; the most commonly involved medications were antipsychotics (35.4%) and benzodiazepines (14.4%). Of 267 with a history of falls or hip fracture, 67.8% received an interacting medication, with selective serotonin reuptake inhibitors (33.1%), antipsychotics (30.7%), and anticonvulsants (25.1%) being most commonly involved. Using separate multivariable logistic regression models, factors associated with DDIs in dementia or cognitive impairment and falls or fractures included age 85 and older (adjusted odds ratio (aOR) = 0.38, 95% confidence interval (CI) = 0.24-0.60 and aOR = 0.48, 95% CI = 0.24-0.96, respectively), taking five to eight medications (aOR = 2.06, 95% CI = 1.02-4.16 and aOR = 4.76, 95% CI = 1.68-13.5, respectively), taking nine or more medications (aOR = 1.99, 95% CI = 1.03-3.85 and aOR = 3.68, 95% CI = 1.41-9.61, respectively), and being a long-stay resident (aOR = 1.80, 95% CI = 1.04-3.12 and aOR = 2.35, 95% CI = 1.12-4.91, respectively).

CONCLUSION

DDIs were common in older nursing home residents with dementia or cognitive impairment or a history of falls or fractures.

Prevalence and impact of fall-risk-increasing drugs, polypharmacy, and drug-drug interactions in robust versus frail hospitalised falls patients: a prospective cohort study

BACKGROUND

Several measures of medication exposure are associated with adverse outcomes in older people. Exposure to and the clinical outcomes of these measures in robust versus frail older inpatients are not known.

OBJECTIVE

In older robust and frail patients admitted to hospital after a fall, we investigated the prevalence and clinical impact of fall-risk-increasing drugs (FRIDs), total number of medications, and drug-drug interactions (DDIs).

METHODS

Patients ≥60 years of age admitted with a fall to a tertiary referral teaching hospital in Sydney were recruited and frailty was assessed. Data were collected at admission, discharge, and 2 months after admission.

RESULTS

A total of 204 patients were recruited (mean age 80.5 ± 8.3 years), with 101 robust and 103 frail. On admission, compared with the robust, frail participants had significantly higher mean ± SD number of FRIDs (frail 3.4 ± 2.2 vs. robust 1.6 ± 1.5, P < 0.0001), total number of medications (9.8 ± 4.3 vs. 4.4 ± 3.3, P < 0.0001), and DDI exposure (35 vs. 5 %, P = 0.001). Number of FRIDs on discharge was significantly associated with recurrent falls [odds ratio (OR) 1.7 (95 % confidence interval [CI] 1.3-2.1)], which were most likely to occur with 1.5 FRIDs in the frail and 2.5 FRIDs in the robust. Number of medications on discharge was also associated with recurrent falls [OR 1.2 (1.0-1.3)], but DDIs were not.

CONCLUSION

Exposure to FRIDs and other measures of high-risk medication exposures is common in older people admitted with falls, especially the frail. Number of FRIDs and to a lesser extent total number of medicines at discharge were associated with recurrent falls.

Medication misadventures in older adults: literature from 2013

The objective of this paper is to review articles published in 2013 examining drug-related problems in the elderly and comment on their potential impact on clinical practice. To identify articles, we did a systematic search of the English-language literature restricted to those aged 65 + from January 2013 to December 2013 using Medline and Google Scholar and a combination of the following search terms: drug-related problems, medication-related problems, medication errors, suboptimal prescribing, inappropriate prescribing, underutilization, polypharmacy, medication monitoring, medication dispensing, medication administration, medication adherence, adverse drug events, and adverse drug withdrawal events. A manual search of major general medicine and clinical pharmacology journals was also conducted to identify additional articles. A total of 51 articles were identified of which 20 were chosen to highlight. Three were annotated and critiqued and the additional 17 articles were summarized in an appendix. One article reported the results of a randomized controlled trial that showed that a pharmacist intervention successfully reduced suboptimal prescribing in older hospital patients. Another paper from this group previously reported data from the same study showing that the intervention also reduced medication related readmissions to the hospital. An observational study compared the use of two thiazide diuretics in older outpatients. They found that chlorthalidone was more likely to cause hypokalemia than hydrochlorothiazide. Finally, in a randomized controlled trial a pharmacist intervention resulted in the reduction of anticholinergic burden but did result in an improvement in cognition. These studies highlight that medication errors and adverse drug events continue to be important issues for health care professionals caring for older adults.