Under-representation of older adults in pharmacokinetic and pharmacodynamic studies: a solvable problem?

Temporal changes in characteristics and external validity of randomized controlled trials in older people from 2012 to 2019

BACKGROUND

Older individuals are often underrepresented in clinical trials. In 2012 only 7% of RCT's specifically studied older people and their geriatric characteristics were poorly reported. The aim of this review was to investigate temporal changes in characteristics and external validity of randomized controlled trials in older people from 2012 to 2019.

METHODS

PubMed was searched for randomized clinical trials (RCTs) published in 2019. Firstly, the proportion of RCTs specially designed for older people were determined by the following criteria: a reported mean age of ≥ 70 years or a lower age cutoff of ≥ 55. Secondly, the trials with a majority of older people, defined by a reported mean age of ≥ 60 years, were screened for reporting of geriatric assessments. Both parts were compared with identical reviews performed in 2012.

RESULTS

From a 10% random sample, 1446 RCTs were included in this systematic review. First, 8% of trials were specifically designed for older people in 2019 compared to 7% in 2012. Secondly, 25% of the trials included a majority of older people in 2019, compared to 22% in 2012. Thirdly, in 52% of these trials in 2019 one or more of the geriatric assessments were reported compared to 34% in 2012.

CONCLUSIONS

Although in 2019 the proportion of published RCTs specifically designed for older people remains low, more characteristics on geriatric assessments were reported compared to 2012. Continued efforts should be paid to increase both the number and the validity of trials for older people.

Polypharmacy and precision medicine

Precision medicine is an approach to maximise the effectiveness of disease treatment and prevention and minimise harm from medications by considering relevant demographic, clinical, genomic and environmental factors in making treatment decisions. Precision medicine is complex, even for decisions about single drugs for single diseases, as it requires expert consideration of multiple measurable factors that affect pharmacokinetics and pharmacodynamics, and many patient-specific variables. Given the increasing number of patients with multiple conditions and medications, there is a need to apply lessons learned from precision medicine in monotherapy and single disease management to optimise polypharmacy. However, precision medicine for optimisation of polypharmacy is particularly challenging because of the vast number of interacting factors that influence drug use and response. In this narrative review, we aim to provide and apply the latest research findings to achieve precision medicine in the context of polypharmacy. Specifically, this review aims to (1) summarise challenges in achieving precision medicine specific to polypharmacy; (2) synthesise the current approaches to precision medicine in polypharmacy; (3) provide a summary of the literature in the field of prediction of unknown drug-drug interactions (DDI) and (4) propose a novel approach to provide precision medicine for patients with polypharmacy. For our proposed model to be implemented in routine clinical practice, a comprehensive intervention bundle needs to be integrated into the electronic medical record using bioinformatic approaches on a wide range of data to predict the effects of polypharmacy regimens on an individual. In addition, clinicians need to be trained to interpret the results of data from sources including pharmacogenomic testing, DDI prediction and physiological-pharmacokinetic-pharmacodynamic modelling to inform their medication reviews. Future studies are needed to evaluate the efficacy of this model and to test generalisability so that it can be implemented at scale, aiming to improve outcomes in people with polypharmacy.

Population Pharmacokinetics of Piperacillin/Tazobactam Across the Adult Lifespan

BACKGROUND AND OBJECTIVE

Piperacillin/tazobactam is one of the most frequently used antimicrobials in older adults. Using an opportunistic study design, we evaluated the pharmacokinetics of piperacillin/tazobactam as a probe drug to evaluate changes in antibacterial drug exposure and dosing requirements, including in older adults.

METHODS

A total of 121 adult patients were included. The population pharmacokinetic models that best characterized the observed plasma concentrations of piperacillin and tazobactam were one-compartment structural models with zero-order input and linear elimination.

RESULTS

Among all potential covariates, estimated creatinine clearance had the most substantial impact on the elimination clearance for both piperacillin and tazobactam. After accounting for renal function and body size, there was no remaining impact of frailty on the pharmacokinetics of piperacillin and tazobactam. Monte Carlo simulations indicated that renal function had a greater impact on the therapeutic target attainment than age, although these covariates were highly correlated. Frailty, using the Canadian Study of Health and Aging Clinical Frailty Scale, was assessed in 60 patients who were ≥ 65 years of age.

CONCLUSIONS

The simulations suggested that adults ≤ 50 years of age infected with organisms with higher minimum inhibitory concentrations may benefit from continuous piperacillin/tazobactam infusions (12 g/day of piperacillin component) or extended infusions of 4 g every 8 hours. However, for a target of 50% fT + minimum inhibitory concentration, dosing based on renal function is generally preferable to dosing by age, and simulations suggested that patients with creatinine clearance ≥ 120 mL/min may benefit from infusions of 4 g every 8 hours for organisms with higher minimum inhibitory concentrations.

Intensive vs. conventional blood pressure goals in older patients with type 2 diabetes: a systematic review and meta-analysis

PURPOSE

Assess the effect of intensive vs conventional blood pressure goals on patient-important outcomes in older adults with type 2 diabetes.

METHODS

A comprehensive search was performed using electronic databases. Randomized controlled trials comparing intensive vs conventional blood pressure goals in adults over 60 years of age with type 2 diabetes were included. Events were evaluated using a modified Mantel-Haenszel meta-analysis with Peto's method. Study selection and data extraction were performed independently and in duplicate.

RESULTS

Seven trials were included. A 19% risk reduction (OR 0.81; 95% CI 0.69-0.95; I² = 8%; p = 0.35) in the occurrence of major adverse cardiovascular events (MACE) and 37% risk reduction (OR 0.63; 95% CI 0.51-0.79; I² = 0%; p = 0.56) in the occurrence of fatal or non-fatal stroke was documented in the intensive treatment group. There were no differences in the occurrence of all-cause mortality, cardiovascular mortality, non-fatal myocardial infarction, and peripheral vascular disease. Data regarding treatment adverse effects and microvascular outcomes was scarce.

CONCLUSIONS

Intensive blood pressure goals in older patients with diabetes were associated with a lower risk of stroke and MACE, but not with all-cause mortality, cardiovascular mortality, non-fatal myocardial infarction, and peripheral vascular disease.

A novel simulation-based approach to training for recruitment of older adults to clinical trials

BACKGROUND

The need to engage adults, age 65 and older, in clinical trials of conditions typical in older populations, (e.g. hypertension, diabetes mellitus, Alzheimer's disease and related dementia) is exponentially increasing. Older adults have been markedly underrepresented in clinical trials, often exacerbated by exclusionary study criteria as well as functional dependencies that preclude participation. Such dependencies may further exacerbate communication challenges. Consequently, the evidence of what works in subject recruitment is less generalizable to older populations, even more so for those from racial and ethnic minority and low-income communities.

METHODS

To support capacity of research staff, we developed a virtual, three station simulation (Group Objective Structured Clinical Experience-GOSCE) to teach research staff communication skills. This 2-h course included a discussion of challenges in recruiting older adults; skills practice with Standardized Participants (SPs) and faculty observer who provided immediate feedback; and debrief to highlight best practices. Each learner had opportunities for active learning and observational learning. Learners completed a retrospective pre-post survey about the experience. SP completed an 11-item communication checklist evaluating the learner on a series of established behaviorally anchored communication skills (29).

RESULTS

In the research staff survey, 92% reported the overall activity taught them something new; 98% reported it provided valuable feedback; 100% said they would like to participate again. In the SP evaluation there was significant variation: the percent well-done of items by case ranged from 25-85%.

CONCLUSIONS

Results from this pilot suggest that GOSCEs are a (1) acceptable; (2) low cost; and (3) differentiating mechanism for training and assessing research staff in communication skills and structural competency necessary for participant research recruitment.

Clinical Trial Diversity: An Opportunity for Improved Insight into the Determinants of Variability in Drug Response

Although the number of countries participating in pivotal trials submitted to enable drug registration has nearly doubled over the past 25 years, there has not been a substantial increase in the diversity of clinical trial populations. In parallel, our understanding of factors that influence medicine response and variability has continued to evolve. The notion of intrinsic and extrinsic sources of variability has been embedded into different regulatory guidelines, including the recent guideline on the importance of enhancing the diversity of clinical trial populations.

In addition to presenting the clinical and scientific reasons for ensuring that clinical trial populations represent the demographics of patient populations, this overview outlines the efforts of regulatory agencies, patient advocacy groups and clinical researchers to attain this goal through strategies to meet representation in recruitment targets and broaden eligibility criteria. Despite these efforts, challenges to participation in clinical trials remain, and certain groups continue to be underrepresented in development programmes. These challenges are amplified when the representativeness of specific groups may vary across countries and regions in a global clinical programme.

Whilst enhanced trial diversity is a critical step towards ensuring that results will be representative of patient populations, a concerted effort is required to characterise further the factors influencing interindividual and regional differences in response for global populations. Quantitative clinical pharmacology principles should be applied to allow extrapolation of data across groups or regions as well as provide insight into the effect of patient‐specific characteristics on a medicine's dose rationale and efficacy and safety profiles.

Attitudes of ambulatory care older Nepalese patients towards deprescribing and predictors of their willingness to deprescribe

INTRODUCTION

Older adults continue to receive potentially inappropriate medications necessitating the need for medication optimization, by deprescribing. To ensure a holistic approach to deprescribing, it is essential to understand the perception of older adults towards deprescribing. This study aimed to assess the attitude of older ambulatory patients towards deprescribing and to identify factors predicting their willingness to deprescribe.

METHODS

A cross-sectional survey was conducted in central Nepal between March and September 2019 among 385 older ambulatory care patients (aged ⩾65 years) who were taking at least one regular medicine. The perception of patients towards deprescribing was assessed using the revised Patients' Attitudes Towards Deprescribing (rPATD) questionnaire via a face-to-face interview method. Descriptive statistics were performed to describe patients' characteristics and their attitudes towards deprescribing. A multivariate logistic regression analysis was used to determine predictors of the willingness of older ambulatory patients towards deprescribing.

RESULTS

The median [interquartile range (IQR)] age of patients was 72 (8) years. Nearly three in five patients (64.9%) had hypertension, with 11.2% having polypharmacy. More than half of the patients (57.4%) would be willing to stop one or more of their regular medicines if their doctor said it was possible to do so. Regression analysis showed that age [odds ratio (OR) 0.946; 95% CI 0.913, 0.981; p = 0.003] and concerns about stopping medicine score (OR 0.541; 95% CI 0.334, 0.876; p = 0.013) were predictors of the willingness of the older patients towards deprescribing.

CONCLUSION

One in two older ambulatory care patients in Nepal would be willing to have one or more of their medicines deprescribed. The factors predicting their willingness to deprescribe are their age and concerns about stopping medicines. Clinicians should consider discussing the possibility of deprescribing with older patients for the prevention of potential medication-related harms.

PLAIN LANGUAGE SUMMARY

What do older Nepalese patients think about withdrawal or dose reduction of an inappropriate medication?Introduction: Research suggests that older adults (aged ⩾65 years) continue to receive medications that have the potential for harm rather than a benefit. This necessitates the need for withdrawal or dose reduction of such inappropriate medications, the process known as deprescribing. Understanding what older patients think about this process could be a stepping-stone to the general approach for its implementation. Data on deprescribing is lacking from Nepal. Therefore, we designed a survey to explore the attitude of older patients towards deprescribing and factors that could predict their willingness to deprescribe.Methods: This study was conducted between March to September 2019 among 385 older patients who were taking at least one regular medicine and were visiting selected hospitals of Nepal for outpatient services. We performed a face-to-face interview to assess the attitude of patients towards deprescribing using a validated tool called revised Patients' Attitudes Towards Deprescribing (rPATD) questionnaire that quantified the response through scoring. The data were subjected to statistical analysis to determine the attitudes of Nepalese older patients towards deprescribing and to develop a model to predict their willingness to deprescribe.Results: The average age of the participant was 72 years with 65% having hypertension and 11% using more than five medications. Our data suggested that one in two older Nepalese patients would be willing to stop one or more of their regular medications if their doctors said it was possible to do so. Their willingness to deprescribe could be predicted from their age and concerns about stopping medications.Conclusion: Clinicians should consider discussing the possibility of deprescribing with older patients for the prevention of potential medication-related harms.

Incorporating pharmacokinetic data into personalised prescribing for older people: challenges and opportunities

PURPOSE

We discuss the known age-associated changes in drug metabolism and elimination, the potential use of this information when selecting specific therapeutic strategies in older patients, and the steps required to fill the knowledge gap in this field.

METHODS

We conducted a narrative review that encapsulates the current knowledge regarding the main age-associated changes in drug metabolism and elimination and discusses their possible inclusion in current and future personalised prescribing tools for the older patient population.

RESULTS

Despite some progress in this field, the lack of specific information regarding the impact of frailty, pharmacogenomics, and drug-drug, drug-disease, and organ-organ interactions, particularly in subjects > 80 years, currently prevents the routine incorporation of pharmacokinetic data, barring measures of renal function, into personalised prescribing tools.

CONCLUSIONS

The incorporation of pharmacokinetic data into personalised prescribing, an approach based on the consideration of a number of patient's characteristics when selecting the right drug(s) and dose regimen(s) to maximize effectiveness and limit toxicity, remains a hypothetical construct in geriatric care. Pending the inclusion of frail and complex older patients in pre- and post-marketing studies, a better understanding of the key pharmacokinetic alterations of common medications in "real-life" patients, together with the implementation of effective strategies tackling inappropriate prescribing, is likely to improve clinical outcomes and reduce healthcare utilization in the older population.

Medication Management in Frail Older People: Consensus Principles for Clinical Practice, Research, and Education

Frailty is a geriatric condition associated with increased vulnerability to adverse drug events and medication-related harm. Existing clinical practice guidelines rarely provide medication management recommendations specific to frail older people. This report presents international consensus principles, generated by the Optimizing Geriatric Pharmacotherapy through Pharmacoepidemiology Network, related to medication management in frail older people. This consensus comprises 7 principles for clinical practice, 6 principles for research, and 4 principles for education. Principles for clinical practice include (1) perform medication reconciliation and maintain an up-to-date medication list; (2) assess and plan based on individual's capacity to self-manage medications; (3) ensure appropriate prescribing and deprescribing; (4) simplify medication regimens when appropriate to reduce unnecessary burden; (5) be alert to the contribution of medications to geriatric syndromes; (6) regularly review medication regimens to align with changing goals of care; and (7) facilitate multidisciplinary communication among patients, caregivers, and healthcare teams. Principles for research include (1) include frail older people in randomized controlled trials; (2) consider frailty status as an effect modifier; (3) ensure collection and reporting of outcome measures important in frailty; (4) assess impact of frailty on pharmacokinetics and pharmacodynamics; (5) encourage frailty research in under-researched settings; and (6) utilize routinely collected linked health data. Principles for education include (1) provide undergraduate and postgraduate education on frailty; (2) minimize low-value care related to medication management; (3) improve health and medication literacy; and (4) incorporate evidence in relation to frailty into clinical practice guidelines. These principles for clinical practice, research and education highlight different considerations for optimizing medication management in frail older people. These principles can be used in conjunction with existing best practice guidelines to help achieve optimal health outcomes for this vulnerable population. Implementation of the principles will require multidisciplinary collaboration between healthcare professionals, researchers, educators, organizational leaders, and policymakers.

Risks and Benefits of Attention-Deficit/Hyperactivity Disorder Medication on Behavioral and Neuropsychiatric Outcomes: A Qualitative Review of Pharmacoepidemiology Studies Using Linked Prescription Databases

Attention-deficit/hyperactivity disorder (ADHD) medication is one of the most commonly prescribed medication classes in child and adolescent psychiatry, and its use is increasing rapidly in adult psychiatry. However, major questions and concerns remain regarding the benefits and risks of ADHD medication, especially in real-world settings. We conducted a qualitative systematic review of studies that investigated the effects of ADHD medication on behavioral and neuropsychiatric outcomes using linked prescription databases from the last 10 years and identified 40 studies from Europe, North America, and Asia. Among them, 18 used within-individual designs to account for confounding by indication. These studies suggested short-term beneficial effects of ADHD medication on several behavioral or neuropsychiatric outcomes (i.e., injuries, motor vehicle accidents, education, substance use disorder), with estimates suggesting relative risk reduction of 9% to 58% for these outcomes. The within-individual studies found no evidence of increased risks for suicidality and seizures. Replication studies are needed for several other important outcomes (i.e., criminality, depression, mania, psychosis). The available evidence from pharmacoepidemiology studies on long-term effects of ADHD medication was less clear. We discuss time-varying confounding and other limitations that should be considered when interpreting results from pharmacoepidemiology studies. Furthermore, we highlight several knowledge gaps to be addressed in future research and implications for research on mechanisms of outcomes of ADHD medications.

Under-representation of elderly in clinical trials: An analysis of the initial approval documents in the Food and Drug Administration database

Aims

To evaluate the availability of pharmacokinetic, safety and efficacy analyses specifically targeted at elderly, prior to the authorization of drugs.

Methods

A cross‐sectional, structured review of publicly available initial approval documents of Food and Drug Administration‐approved drugs was performed. The 10 most frequently on‐label prescribed drug classes, drugs with known pharmacokinetic differences in the elderly or drugs that are relatively contraindicated in elderly (e.g. anticholinergics or benzodiazepines) were included in the analyses.

Results

In total, 1129 unique active pharmaceutical ingredients were found eligible for the analyses, of these, 506 were found in the Food and Drug Administration database (45%). The initial approval documents were available for 182 drugs. For the majority of the drugs, the initial approval documents in the database showed information on pharmacokinetics in elderly (n = 113; 62%). Furthermore, over time, the availability of information with regard to elderly increased statistically significantly from 0% in the period 1970–1979 to 76% for the period 2010–2018. Information on safety and efficacy was less frequently present, i.e. 42% and 45%, respectively and, moreover, the availability of information did not improve over time.

Conclusion

The under‐representation of elderly in clinical trials thereby challenging the external validity of benefit/risk assessments of launched drugs was confirmed. Priority should be given to a study population that is representative for the target population.

Efficacy and safety of praziquantel in preschool-aged and school-aged children infected with Schistosoma mansoni: a randomised controlled, parallel-group, dose-ranging, phase 2 trial

Background

Praziquantel has been the drug of choice for schistosomiasis control for more than 40 years, yet surprisingly, the optimal dose for children younger than 4 years is not known. We aimed to assess the efficacy and safety of escalating praziquantel dosages in preschool-aged children (PSAC).

Methods

We did a randomised controlled, parallel-group, single-blind, dose-ranging, phase 2 trial in PSAC (2–5 years) and school-aged children (SAC; aged 6–15 years) as a comparator group in southern Côte d'Ivoire. Children were randomly assigned (1:1:1:1) to 20 mg/kg, 40 mg/kg, or 60 mg/kg praziquantel or placebo. Participants, investigators, and laboratory technicians were masked to group assignment, while the investigator providing treatment was aware of the treatment group. The primary objective was to estimate the nature of the dose–response relation in terms of cure rate using the Kato Katz technique. Dose–response curves were estimated using E_max models. Available case analysis was done including all participants with primary endpoint data. This trial is registered with International Standard Randomised Controlled Trial, number ISRCTN15280205.

Findings

Between Nov 11, 2014, and Feb 18, 2015, 660 PSAC and 225 SAC were assessed for eligibility; of whom 161 (24%) PSAC and 180 (80%) SAC had a detectable Schistosoma mansoni infection. 161 PSAC were randomly allocated of whom 154 received treatment: 42 were assigned to 20 mg/kg praziquantel, of whom 40 received treatment; 38 were assigned to 40 mg/kg praziquantel, of whom 38 received treatment; 41 were assigned to 60 mg/kg praziquantel, of whom 39 received treatment; and 40 were assigned to placebo, of whom 37 received placebo. 180 SAC were randomly allocated of whom 177 received treatment: 49 were assigned to 20 mg/kg praziquantel, of whom 47 received treatment; 46 were assigned to 40 mg/kg praziquantel, of whom 46 received treatment; 42 were assigned to 60 mg/kg praziquantel, of whom 42 received treatment; and 43 were assigned to placebo, of whom 43 received treatment. Follow-up (available-case) data were available for 143 PSAC and 174 SAC. In PSAC, the 20 mg/kg dose resulted in cure in 23 children (62%; 95% CI 44·8–77·5), 40 mg/kg in 26 children (72%; 54·8–85·8), 60 mg/kg in 25 children (71%; 53·7–85·4), and placebo in 13 children (37%; 21·5–55·1). In SAC, the 20 mg/kg dose resulted in cure in 14 children (30%; 95% CI 17·7–45·8), 40 mg/kg in 31 children (69%; 53·4–81·8), 60 mg/kg in 34 children (83%; 67·9–92·8), and placebo in five children (12%; 4·0–25·6). For both age groups, the number of adverse events was similar among the three praziquantel treatment groups, with fewer adverse events observed in the placebo groups. The most common adverse events in PSAC were diarrhoea (11 [9%] of 124) and stomach ache (ten [8%]) and in SAC were diarrhoea (50 [28%] of 177), stomach ache (66 [37%]), and vomiting (26 [15%]) 3 h post treatment. No serious adverse events were reported.

Interpretation

Praziquantel shows a flat dose-response and overall lower efficacy in PSAC compared with in SAC. In the absence of treatment alternatives, a single dose of praziquantel of 40 mg/kg, recommended by the WHO for S mansoni infections in SAC can be endorsed for PSAC in preventive chemotherapy programmes.

Funding

European Research Council.

Optimal management of ADHD in older adults

BACKGROUND

The manifestation of attention-deficit/hyperactivity disorder (ADHD) among older adults has become an interesting topic of interest due to an increasing number of adults aged 50 years and older (≥50 years) seeking assessment for ADHD. Unfortunately, there is a lack of research on ADHD in older adults, and until recently only a few case reports existed.

METHOD

A systematic search was conducted in the databases Medline/PubMed and PsycINFO in order to identify studies regarding ADHD in adults ≥50 years.

RESULTS

ADHD persists into older ages in many patients, but the prevalence of patients fulfilling the criteria for the diagnosis at age ≥50 years is still unknown. It is reason to believe that the prevalence is falling gradually with age, and that the ADHD symptom level is significantly lower in the age group 70-80 years than the group 50-60 years. There is a lack of controlled studies of ADHD medication in adults ≥50 years, but this review suggests that many patients aged ≥50 years experience beneficial effects of pharmacological treatment. The problem with side effects and somatic complications may rise to a level that makes pharmacotherapy for ADHD difficult after the age of 65 years. Physical assessment prior to initiation of ADHD medication in adults ≥50 years should include a thorough clinical examination, and medication should be titrated with low doses initially and with a slow increase. In motivated patients, different psychological therapies alone or in addition to pharmacotherapy should be considered.

CONCLUSION

It is essential when treating older adult patients with ADHD to provide good support based on knowledge and understanding of how ADHD symptoms have affected health, quality of life, and function through the life span. Individualized therapy for each elderly patient should be recommended to balance risk-benefit ratio when pharmacotherapy is considered to be a possible treatment.

New drugs and patient-centred end-points in old age: setting the wheels in motion

Older patients with various degrees of frailty and disability, a key population target of pharmacological interventions in acute and chronic disease states, are virtually neglected in pre-marketing studies assessing the efficacy and safety of investigational drugs. Moreover, aggressively pursuing established therapeutic targets in old age, e.g. blood pressure, serum glucose or cholesterol concentrations, is not necessarily associated with the beneficial effects, and the acceptable safety, reported in younger patient cohorts. Measures of self-reported health and functional status might represent additional, more meaningful, therapeutic end-points in the older population, particularly in patients with significant frailty and relatively short life expectancy, e.g. in the presence of cancer and/or neurodegenerative disease conditions. Strategies enhancing early knowledge about key pharmacological characteristics of investigational drugs targeting older adults are discussed, together with the rationale for incorporating non-traditional, patient-centred, end-points in this ever-increasing group.

Potentially Inappropriate Prescribing in Older Patients Discharged From Acute Care Hospitals to Residential Aged Care Facilities

Background: The frequency of prescribing potentially inappropriate medications (PIMs) in older patients remains high despite evidence of adverse outcomes from their use. Little is known about whether admission to hospital has any effect on appropriateness of prescribing. Objectives: This study aimed to identify the prevalence and nature of PIMs and explore the association of risk factors for receiving a PIM. Methods: This was a prospective study of 206 patients discharged to residential aged care facilities from acute care. All patients were at least 70 years old and were admitted between July 2005 and May 2010; their admission and discharge medications were evaluated. Results: Mean patient age was 84.8 ± 6.7 years; the majority (57%) were older than 85 years, and mean (SD) Frailty Index was 0.42 (0.15). At least 1 PIM was identified in 112 (54.4%) patients on admission and 102 (49.5%) patients on discharge. Of all medications prescribed at admission (1728), 10.8% were PIMs, and at discharge, of 1759 medications, 9.6% were PIMs. Of the total 187 PIMs on admission, 56 (30%) were stopped and 131 were continued; 32 new PIMs were introduced. Of the potential risk factors considered, in-hospital cognitive decline and frailty status were the only significant predictors of PIMs. Conclusions: Although admission to hospital is an opportunity to review the indications for specific medications, a high prevalence of inappropriate drug use was observed. The only associations with PIM use were the frailty status and in-hospital cognitive decline. Additional studies are needed to further evaluate this association.