ThinkCascades: A Tool for Identifying Clinically Important Prescribing Cascades Affecting Older People

Detection of Potential Prescribing Cascades in Multimorbid Older Patients Hospitalised with Acute Illness-An Observational Prospective Prevalence Study

BACKGROUND

Prescribing cascades occur when a new drug is prescribed to treat an adverse drug event caused by an existing medication, resulting in unnecessary, or potentially hazardous additional drugs. To date, there are no published studies assessing the prevalence of prescribing cascades in older hospitalised adults.

OBJECTIVE

To investigate the prevalence of prescribing cascades in hospitalised older adults.

METHODS

We conducted a prospective observational study of adults aged ≥ 65 years with multimorbidity and polypharmacy presenting to hospital with acute unselected medical or surgical illness. Prescribing cascades were identified using two predefined validated explicit cascade lists, i.e. ThinkCascades, and a list derived from a recently published systematic review of prescribing cascades in community-dwelling adults, referred to here as the 'Doherty list'. Potential prescribing cascades were classified as 'definite', 'probable', 'possible', 'uncertain' or 'indeterminate' according to pre-specified criteria.

RESULTS

The study included 385 consecutive patients (55.1% female, mean age 80.2 years, standard deviation 7.3 years). A total of 281 potential prescribing cascades (drug A → drug B) were identified in 152 patients (39.4%). Probable or possible prescribing cascades were identified in 48 patients (12.4%) using the Doherty list and in 44 patients (11.4%) using ThinkCascades. Patients exposed to potential prescribing cascades experienced greater levels of polypharmacy than patients not exposed to prescribing cascades (median interquartile range [IQR] of 12 [9-14] daily drugs versus 9 [IQR 7-11], p < 0.001).

CONCLUSIONS

Potential prescribing cascades were highly prevalent in older hospitalised adults. Practical tools are needed to assist prescribers in prevention, recognition and management of inappropriate prescribing cascades.

Reducing prescribing cascades

Prescribing cascades contribute to the increasing prevalence of polypharmacy and its associated risks, where a drug-induced adverse event is misinterpreted as a new condition and treated with additional medications. Notable cascades include the use of anticholinergics leading to cognitive impairment, dyspepsia or constipation, which then prompt prescriptions for dementia medications, proton pump inhibitors or laxatives, respectively. Similarly, calcium channel blockers and gabapentinoids often induce oedema, resulting in unnecessary diuretic use. Strategies for prevention include careful review of adverse effects, deprescribing where appropriate and clinician education to improve symptom interpretation and prescribing practices. Recognising these cascades can mitigate unnecessary interventions and improve patient outcomes.

High-Throughput Screening for Prescribing Cascades Among Real-World Angiotensin-II Receptor Blockers (ARBs) Initiators

Objective

Angiotensin-II Receptor Blockers (ARBs) are commonly prescribed; however, their adverse events may prompt new drug prescription(s), known as prescribing cascades. We aimed to identify potential ARB-induced prescribing cascades using high-throughput sequence symmetry analysis.

Methods

Using claims data from a national sample of Medicare beneficiaries (2011-2020), we identified new ARB users aged ≥66 years with continuous enrollment ≥360 days before and ≥180 days after ARB initiation. We screened for initiation of 446 other (non-antihypertensive) 'marker' drug classes within ±90 days of ARB initiation, generating sequence ratios (SRs) reflecting proportions of ARB users starting the marker class after versus before ARB initiation. Adjusted SRs (aSRs) accounted for prescribing trends over time, and for significant aSRs, we calculated the naturalistic number needed to harm (NNTH); significant signals were reviewed by clinical experts for plausibility.

Results

We identified 320,663 ARB initiators (mean ± SD age 76.0 ± 7.2 years; 62.5% female; 91.5% with hypertension). Of the 446 marker classes evaluated, 17 signals were significant, and three (18%) were classified as potential prescribing cascades after clinical review. The strongest signals ranked by the lowest NNTH included benzodiazepine derivatives (NNTH 2130, 95% CI 1437-4525), adrenergics in combination with anticholinergics, including triple combinations with corticosteroids (NNTH 2656, 95% CI 1585-10074), and other antianemic preparations (NNTH 9416, 95% CI 6606-23784). The strongest signals ranked by highest aSR included other antianemic preparations (aSR 1.7, 95% CI 1.19-2.41), benzodiazepine derivatives (aSR 1.18, 95% CI 1.08-1.3), and adrenergics in combination with anticholinergics, including triple combinations with corticosteroids (aSR 1.12, 95% CI 1.03-1.22).

Conclusion

The identified prescribing cascade signals reflected known and possibly under-recognized ARB adverse events in this Medicare cohort. These hypothesis-generating findings require further investigation to determine the extent and impact of these prescribing cascades on patient outcomes.

Pharmacy-led interventions to reverse and prevent prescribing cascades in primary care: a proof-of-concept study

BACKGROUND

Prescribing cascades occur in clinical practice when a medication causes an adverse drug reaction (ADR), which is addressed by prescribing additional medication.

AIM

The aim was to provide proof-of-concept for pharmacy-led interventions to reverse or prevent prescribing cascades.

METHOD

Two community pharmacies each tested two approaches. To reverse prescribing cascades, ten cascades were selected from literature. Dispensing records were screened to identify patients with these cascades. To prevent prescribing cascades, patients who started medications associated with five of these cascades were telephoned one month after their first dispensing to discuss ADRs. Pharmacists assessed the need to intervene together with prescribers. Primary outcome was the proportion of patients with a treatment change initiated. Secondary outcomes were time investment, potential cost-savings, and pharmacists' experiences.

RESULTS

To reverse prescribing cascades, 24 patients were included. For eight the prescriber was consulted, resulting in the reversal of three cascades. Forty-four patients were included to prevent prescribing cascades. Six of them experienced an ADR that could lead to a prescribing cascade. For two patients interventions were conducted to prevent this. The estimated time investment to identify patients possibly in need of intervention was 4.5 h for the reversing approach and 4.8 h for the preventing approach, while follow-up actions required 1.8 h and 0.5 h, respectively. Both approaches could be cost-saving. Pharmacists considered both approaches relevant but identified a knowledge gap on how to intervene for some cascades.

CONCLUSION

Pharmacy-led interventions may reverse and prevent prescribing cascades, but more efficient screening methods and tools are needed before further implementation.

Cross-Cultural Adaptation and Clinical Validation of TIME Criteria to Detect Potentially Inappropriate Medication Use in Older Adults: Methodological Report from the TIME International Study Group

BACKGROUND

Various explicit screening tools, developed mostly in central Europe and the USA, assist clinicians in optimizing medication use for older adults. The Turkish Inappropriate Medication use in oldEr adults (TIME) criteria set, primarily based on the STOPP/START criteria set, is a current explicit tool originally developed for Eastern Europe and subsequently validated for broader use in Central European settings. Reviewed every three months to align with the latest scientific literature, it is one of the most up-to-date tools available. The tool is accessible via a free mobile app and website platforms, ensuring convenience for clinicians and timely integration of updates as needed. Healthcare providers often prefer to use their native language in medical practice, highlighting the need for prescribing tools to be translated and adapted into multiple languages to promote optimal medication practices.

OBJECTIVE

To describe the protocol for cross-cultural and language validation of the TIME criteria in various commonly used languages and to outline its protocol for clinical validation across different healthcare settings.

METHODS

The TIME International Study Group comprised 24 geriatric pharmacotherapy experts from 12 countries. In selecting the framework for the study, we reviewed the steps and outcomes from previous research on cross-cultural adaptations and clinical validations of explicit tools. Assessment tools were selected based on both their validity in accurately addressing the relevant issues and their feasibility for practical implementation. The drafted methodology paper was circulated among the study group members for feedback and revisions leading to a final consensus.

RESULTS

The research methodology consists of two phases. Cross-cultural adaptation/language validation phase follows the 8-step approach recommended by World Health Organization. This phase allows regions or countries to make modifications to existing criteria or introduce new adjustments based on local prescribing practices and available medications, as long as these adjustments are supported by current scientific evidence. The second phase involves the clinical validation, where participants will be randomized into two groups. The control group will receive standard care, while the intervention group will have their treatment evaluated by clinicians who will review the TIME criteria and consider its recommendations. A variety of patient outcomes (i.e., number of hospital admissions, quality of life, number of regular medications [including over the counter medications], geriatric syndromes and mortality) in different healthcare settings will be investigated.

CONCLUSION

The outputs of this methodological report are expected to promote broader adoption of the TIME criteria. Studies building on this work are anticipated to enhance the identification and management of inappropriate medication use and contribute to improved patient outcomes.

A-I-D for cascades: an application of the Behaviour Change Wheel to design a theory-based intervention for addressing prescribing cascades in primary care

BACKGROUND

Prescribing cascades, which occur when a medication is used to treat the side effect of another medication, are important contributors to polypharmacy. There is an absence of studies that evaluate interventions to address them. We describe an application of the Behaviour Change Wheel (BCW) to design theory-informed interventions for addressing prescribing cascades within interprofessional primary care teams.

METHODS

The BCW framework was applied to guide intervention development. This report describes the first seven steps. Three behaviours were developed based on data collected from two qualitative studies exploring why and how cascades occur across practice settings. A target behaviour was selected and the COM-B model was applied to identify relevant factors for interprofessional primary care teams. Relevant intervention types, policy options, and corresponding behaviour change techniques (BCTs) were identified, and intervention examples drafted. Prioritization of behaviours and intervention examples were guided by the APEASE criteria.

RESULTS

The three behaviours involved supporting: (1) healthcare providers (HCPs) to ask about, investigate and manage cascades, (2) the public to ask about prescribing cascades, and (3) the public to share medication histories and experiences with HCPs. The team selected the HCP behaviour, A-I-D (ask, investigate, deprescribe), for intervention development. Psychological capability and physical opportunity were the most relevant COM-B components. Ten intervention options comprised of BCTs were developed, which are ready for further prioritization by stakeholders. These can be grouped into: provision of educational materials for use by HCPs; provision of consultation or training to support HCPs; and knowledge mobilization strategies. Through the process, the team identified that development of a practice guidance tool, which assists HCPs to investigate and manage prescribing cascades, is needed to support further intervention development.

CONCLUSIONS

The BCW framework guided the design of intervention examples to support primary HCPs practicing in interprofessional teams to address prescribing cascades. When identifying interventions for future consultation, creation of a practice guidance tool was prioritized as it underpins all proposed interventions for addressing prescribing cascades in practice. Further research is needed to determine what primary HCPs would need in this practice guidance tool and how it will be used in practice, to support its development.

Identifying and quantifying potentially problematic prescribing cascades in clinical practice: A mixed-methods study

BACKGROUND

A prescribing cascade occurs when medication causes an adverse drug reaction (ADR) that leads to the prescription of additional medication. Prescribing cascades can cause excess medication burden, which is of particular concern in older adults. This study aims to identify and quantify potentially problematic prescribing cascades relevant for clinical practice.

METHODS

A mixed-methods study was conducted. First, prescribing cascades were identified through literature search. An expert panel (n = 16) of pharmacists and physicians assessed whether these prescribing cascades were potentially problematic. Next, a cohort study quantified potentially problematic prescribing cascades in adults using Dutch community pharmacy data for the period 2015-2020. Additionally, the influence of multiple medications potentially causing the same ADR was evaluated. Prescription sequence symmetry analysis was used to calculate adjusted sequence ratios (aSRs), adjusting for temporal prescribing trends. An aSR >1.0 indicates the occurrence of a prescribing cascade. In a subgroup analysis, aSRs were calculated for older adults.

RESULTS

Seventy-six prescribing cascades were identified in literature and three were provided by experts. Of these, 66 (83.5%) were considered potentially problematic. A significant positive aSR for the medication sequence was found for 41 (62.1%) of these prescribing cascades. The highest aSR was found for amiodarone potentially causing hypothyroidism treated with thyroid hormones (4.63 [95% confidence interval 4.40-4.85]), based on 565 incident users. The biggest population (n = 34,645) was found for angiotensin converting enzyme-inhibitors potentially causing urinary tract infections treated with antibiotics. Regarding four potential ADRs, the aSRs were higher for people using multiple medications that cause the same ADR as compared to people using only one of those medications. Among older adults the aSRs remained significant for 37 prescribing cascades.

CONCLUSION

An overview was generated of potentially problematic prescribing cascades relevant for clinical practice. These results can support healthcare providers to intervene and reduce medication burden for older adults.

Preventing Prescribing Cascades: Ensuring Medication Safety for Older Adults

PURPOSE

To define prescribing cascades (PCs) and provide tools to identify PCs, including the most common PCs described in the literature. PCs lead to the accumulation of medications prescribed to older adults, disproportionately affecting those who often have additional health care complexities, such as multiple chronic conditions and multiple transitions of care.

METHOD

Review of recent research efforts to identify and describe evolving clinical practice interventions to detect and reverse PCs.

RESULTS

Clinicians can contribute to mitigating PCs through better understanding of how PCs occur in practice. Armed with this knowledge, clinical team members can implement proposed strategies and techniques to engage in primary and secondary prevention of PCs.

CONCLUSION

Ultimately, PCs are a culprit of preventable medication harm. Several tools are presented, which are initiated through maintaining a high index of suspicion for PCs in the evaluation of a new symptom presentation by older patients. [Journal of Gerontological Nursing, 50(9), 7-11.].

Drug stewardship in chronic kidney disease to achieve effective and safe medication use

People living with chronic kidney disease (CKD) often experience multimorbidity and require polypharmacy. Kidney dysfunction can also alter the pharmacokinetics and pharmacodynamics of medications, which can modify their risks and benefits; the extent of these changes is not well understood for all situations or medications. The principle of drug stewardship is aimed at maximizing medication safety and effectiveness in a population of patients through a variety of processes including medication reconciliation, medication selection, dose adjustment, monitoring for effectiveness and safety, and discontinuation (deprescribing) when no longer necessary. This Review is aimed at serving as a resource for achieving optimal drug stewardship for patients with CKD. We describe special considerations for medication use during pregnancy and lactation, during acute illness and in patients with cancer, as well as guidance for the responsible use of over-the-counter drugs, herbal remedies, supplements and sick-day rules. We also highlight inequities in medication access worldwide and suggest policies to improve access to quality and essential medications for all persons with CKD. Further strategies to promote drug stewardship include patient education and engagement, the use of digital health tools, shared decision-making and collaboration within interdisciplinary teams. Throughout, we position the person with CKD at the centre of all drug stewardship efforts.

Community pharmacists' awareness, identification, and management of prescribing cascades: A cross-sectional survey

BACKGROUND

Prescribing cascades can lead to unnecessary medication use, healthcare costs, and patient harm. Pharmacists oversee prescriptions from multiple prescribers and are well positioned to identify such cascades, making pharmacists key stakeholders to address them.

OBJECTIVES

To evaluate community pharmacists' awareness, identification, and management of prescribing cascades and to assess behavioural determinants that may be targeted in future strategies to minimise inappropriate prescribing cascades.

METHODS

An online survey was developed using the Theoretical Domains Framework (TDF) and emailed to all registered community pharmacists in Ireland (n = 3775) in November 2021. Quantitative data were analysed using descriptive and inferential statistics. Free-text sections were given to capture reasons for non-resolution of identified prescribing cascades and suggestions to aid prescribing cascade identification and management; this text underwent content analysis.

RESULTS

Of the 220 respondents, 51% were aware of the term 'prescribing cascade' before the survey, whilst 69% had identified a potentially inappropriate prescribing cascade in practice. Over one third were either slightly confident (26.4%) or not confident at all (10%) in their ability to identify potentially inappropriate prescribing cascades in patients' prescriptions before the survey, whilst 55.2% were concerned that patients were receiving prescribing cascades they had not identified. Most respondents wanted further information/training to help prescribing cascade identification (88.3%) and management (86.1%). Four predominant TDF domains identified were common to both i) influencing non-resolution of identified prescribing cascades and ii) in the suggestions to help identify and manage prescribing cascades: 'Environmental Context and Resources', 'Social/Professional Role and Identity', 'Social Influences' and 'Memory, Attention and Decision Processes'.

CONCLUSIONS

There is a clear need to provide additional resources to help community pharmacists identify and manage prescribing cascades. These findings will support the development of theory-informed behaviour change strategies to aid the minimisation of inappropriate prescribing cascades and decrease the risk of medication-related harm for patients.

Optimising the use of electronic medical records for large scale research in psychiatry

The explosion and abundance of digital data could facilitate large-scale research for psychiatry and mental health. Research using so-called "real world data"-such as electronic medical/health records-can be resource-efficient, facilitate rapid hypothesis generation and testing, complement existing evidence (e.g. from trials and evidence-synthesis) and may enable a route to translate evidence into clinically effective, outcomes-driven care for patient populations that may be under-represented. However, the interpretation and processing of real-world data sources is complex because the clinically important 'signal' is often contained in both structured and unstructured (narrative or "free-text") data. Techniques for extracting meaningful information (signal) from unstructured text exist and have advanced the re-use of routinely collected clinical data, but these techniques require cautious evaluation. In this paper, we survey the opportunities, risks and progress made in the use of electronic medical record (real-world) data for psychiatric research.

Stakeholder perceptions of and attitudes towards problematic polypharmacy and prescribing cascades: a qualitative study

INTRODUCTION

Problematic polypharmacy is the prescribing of five or more medications potentially inappropriately. Unintentional prescribing cascades represent an under-researched aspect of problematic polypharmacy and occur when an adverse drug reaction (ADR) is misinterpreted as a new symptom resulting in the initiation of a new medication. The aim of this study was to elicit key stakeholders' perceptions of and attitudes towards problematic polypharmacy, with a focus on prescribing cascades.

METHODS

qualitative one-to-one semi-structured interviews were conducted with predefined key stakeholder groups. Inductive thematic analysis was employed.

RESULTS

Thirty-one stakeholders were interviewed: six patients, two carers, seven general practitioners, eight pharmacists, four hospital doctors, two professional organisation representatives and two policymakers. Three main themes were identified: (i) ADRs and prescribing cascades-a necessary evil. Healthcare professionals (HCPs) expressed concern that experiencing an ADR would negatively impact patients' confidence in their doctor. However, patients viewed ADRs pragmatically as an unpredictable risk. (ii) Balancing the risk/benefit tipping point. The complexity of prescribing decisions in the context of polypharmacy made balancing this tipping point challenging. Consequently, HCPs avoided medication changes. (iii) The minefield of medication reconciliation. Stakeholders, including patients and carers, viewed medication reconciliation as a perilous activity due to systemic communication deficits.

CONCLUSION

Stakeholders believed that at a certain depth of polypharmacy, the risk that a new symptom is being caused by an existing medication becomes incalculable. Therefore, in the absence of harm, medication changes were avoided. However, medication reconciliation post hospital discharge compelled prescribing decisions and was seen as a high-risk activity by stakeholders.

Classification system for primary care provider eConsults about medications for older adults with frailty

BACKGROUND

Providing primary care for people with frailty can be challenging due to an increased risk of adverse outcomes and use of potentially inappropriate medications which may exacerbate characteristics of frailty. eConsult is a service where primary care providers can receive timely specialist advice for their patients through a secure web-based application. We aimed to develop a classification system to characterize medication-focused eConsult questions for older adults with frailty and assess its usability.

METHODS

A classification system was developed and refined over three cycles of improvement through a cross-sectional study of 35 cases categorized as medication-focused from cases submitted in 2019 for patients aged 65 or older with frailty through the Champlain BASE eConsult service (Ontario, Canada). The final classification system was then applied to each case.

RESULTS

The classification system contains 5 sections: (1) case descriptives; (2) intent and type of question; (3) medication recommendations and additional information in the response; (4) medication classification; and (5) potentially inappropriate medications. Among the 35 medication-focused cases, the most common specialties consulted were endocrinology (9 cases, 26%) and cardiology (5 cases, 14%). Medication histories were available for 29 cases (83%). Many patients were prescribed potentially inappropriate medications based on explicit tools (AGS Beers Criteria®, STOPPFall, Anticholinergic Cognitive Burden Scale, ThinkCascades) yet few consults inquired about these medications.

CONCLUSION

A classification system to describe medication-related eConsult cases for patients experiencing frailty was developed and applied to 35 eConsult cases. It can be applied to more cases to identify professional development opportunities and enhancements for eConsult services.

Association of a calcium channel blocker and diuretic prescribing cascade with adverse events: A population-based cohort study

BACKGROUND

Prescribing cascades occur when a drug adverse event is misinterpreted as a new medical condition and a second, potentially unnecessary drug, is prescribed to treat the adverse event. The population-level consequences of prescribing cascades remain unknown.

METHODS

This population-based cohort study used linked health administrative databases in Ontario, Canada. The study included community-dwelling adults, 66 years of age or older with hypertension and no history of heart failure (HF) or diuretic use in the prior year, newly dispensed a calcium channel blocker (CCB). Individuals subsequently dispensed a diuretic within 90 days of incident CCB dispensing were classified as the prescribing cascade group, and compared to those not dispensed a diuretic, classified as the non-prescribing cascade group. Those with and without a prescribing cascade were matched one-to-one on the propensity score and sex. The primary outcome was a serious adverse event (SAE), which was the composite of emergency room visits and hospitalizations in the 90-day follow-up period. We estimated hazard ratios (HRs) with 95% confidence intervals (CI) for SAE using an Andersen-Gill recurrent events regression model.

RESULTS

Among 39,347 older adults with hypertension and no history of HF who were newly dispensed a CCB, 1881 (4.8%) had a new diuretic dispensed within 90 days after CCB initiation. Compared to the non-prescribing cascade group, those in the prescribing cascade group had higher rates of SAEs (HR: 1.21, 95% CI: 1.02-1.43).

CONCLUSIONS

The CCB-diuretic prescribing cascade was associated with an increased rate of SAEs, suggesting harm beyond prescribing a second drug therapy. Our study raises awareness of the downstream impact of the CCB-diuretic prescribing cascade at a population level and provides an opportunity for clinicians who identify this prescribing cascade to review their patients' medications to determine if they can be optimized.

Prescribing cascades in ambulatory care: A structured synthesis of evidence

The strength of evidence for specific ambulatory care prescribing cascades, in which a marker drug is used to treat an adverse event caused by an index drug, has not been well characterized. To perform a structured, systematic, and transparent review of the evidence supporting ambulatory care prescribing cascades. Ninety-four potential prescribing cascades identified through a previously published systematic review. Systematic search of the literature to further characterize prescribing cascades. (1) Grading of evidence based on observational studies investigating associations between index and marker drugs, including: Level I-strong evidence [i.e. multiple high-quality studies]; Level II-moderate evidence [i.e. single high-quality study]; Level III-fair evidence [no high-quality studies but one or more moderate-quality studies]; and Level IV-poor evidence [other]. (2) Listing of the adverse event associated with the index drug in the product's United States Food and Drug Administration (FDA) label. (3) Synthesis of the evidence supporting mechanisms linking index drugs and associated adverse events. Of 99 potential cascades, 94 were supported by one or more confirmatory observational studies and were therefore included in this review. The 94 cascades related to 30 types of adverse drug reactions affecting 10 different anatomic/physiologic systems and were investigated by a total of 88 confirmatory studies, including prescription sequential symmetry analysis (n = 51), cohort (n = 30), and case-control (n = 7) studies. Overall, the evidence from observational studies was strong for 18 (19.1%) prescribing cascades, moderate for 61 (64.9%), fair for 13 (13.8%), and poor for 2 (2.1%). Although the evidence supporting mechanisms that link index drugs and associated adverse events was variable, FDA labels included information about the adverse event associated with the index drug for most (n = 86) but not all of the 94 prescribing cascades. Although we identified 18 of 94 prescribing cascades supported by strong clinical evidence and most adverse events associated with index drugs are included in FDA label, the evidentiary basis for prescribing cascades varies, with many requiring further evidence of clinical relevance.

Prescribing Cascades with Recommendations to Prevent or Reverse Them: A Systematic Review

BACKGROUND

To reduce prescribing cascades occurring in clinical practice, healthcare providers require information on the prescribing cascades they can recognize and prevent.

OBJECTIVE

This systematic review aims to provide an overview of prescribing cascades, including dose-dependency information and recommendations that healthcare providers can use to prevent or reverse them.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was followed. Relevant literature was identified through searches in OVID MEDLINE, OVID Embase, OVID CINAHL, and Cochrane. Additionally, Web of Science and Scopus were consulted to analyze reference lists and citations. Publications in English were included if they analyzed the occurrence of prescribing cascades. Prescribing cascades were included if at least one study demonstrated a significant association and were excluded when the adverse drug reaction could not be confirmed in the Summary of Product Characteristics. Two reviewers independently extracted and grouped similar prescribing cascades. Descriptive summaries were provided regarding dose-dependency analyses and recommendations to prevent or reverse these prescribing cascades.

RESULTS

A total of 95 publications were included, resulting in 115 prescribing cascades with confirmed adverse drug reactions for which at least one significant association was found. For 52 of these prescribing cascades, information regarding dose dependency or recommendations to prevent or reverse prescribing cascades was found. Dose dependency was analyzed and confirmed for 12 prescribing cascades. For example, antipsychotics that may cause extrapyramidal syndrome followed by anti-parkinson drugs. Recommendations focused on dosage lowering, discontinuing medication, and medication switching. Explicit recommendations regarding alternative options were given for three prescribing cascades. One example was switching to ondansetron or granisetron when extrapyramidal syndrome is experienced using metoclopramide.

CONCLUSIONS

In total, 115 prescribing cascades were identified and an overview of 52 of them was generated for which recommendations to prevent or reverse them were provided. Nonetheless, information regarding alternative options for managing prescribing cascades was scarce.

Exploring physician gender bias in the initiation of prescribing cascades for older men and women: a qualitative clinical vignette study protocol

INTRODUCTION

A prescribing cascade occurs when a drug is prescribed to manage the often unrecognised side effect of another drug; these cascades are of particular concern for older adults who are at heightened risk for drug-related harm. It is unknown whether, and to what extent, gender bias influences physician decision-making in the context of prescribing cascades. The aim of this transnational study is to explore the potential impact of physician implicit gender biases on prescribing decisions that may lead to the initiation of prescribing cascades in older men and women in two countries, namely: Canada and Italy.

METHODS AND ANALYSIS

Male and female primary care physicians at each site will be randomised 1:1 to a case vignette that features either a male or female older patient who presents with concerns consistent with the side effect of a medication they are taking. During individual interviews, while masked to the true purpose of the study, participants will read the vignette and use the think-aloud method to describe their ongoing thought processes as they consider the patient's concerns and determine a course of action. Interviews will be recorded, transcribed verbatim and thematic analysis will be conducted to highlight differences in decisions in the interviews/transcripts, using a common analytical framework across the sites.

ETHICS AND DISSEMINATION

This study has received ethics approval at each study site. Verbal informed consent will be received from participants prior to data collection and all data will be deidentified and stored on password-protected servers. Results of this study will be disseminated through peer-reviewed journal articles and presented at relevant national and international conferences.

Research on prescribing cascades: a scoping review

Background: The concept of prescribing cascades has been proposed for more than 20 years, but the research progress and cognitive level varied in different countries. The aim of this study was to systematically evaluate the current status of relevant original research on prescribing cascades, and to provide references for further research and continuous improvement in clinical practice. Methods: We searched three English databases and four Chinese databases from inception until January 2022. Relevant studies about prescribing cascades meeting the eligibility criteria were extracted independently by two reviewers, and a descriptive analysis was conducted to compare the methods and outcomes of the included studies. Results: A total of 32 studies involving 7,075,200 patients in 11 countries were included, including 13 cross-sectional studies, 11 case reports, 7 cohort studies, and 1 case-control study. The target population was mainly elderly people (24 studies). The purpose of the included studies could be divided into three categories: prevention (4 studies), identification (17 studies), and resolution (11 studies) of prescribing cascades. 49 prescribing cascade routes were identified and mainly attributed to the cardiovascular system, most primary diseases of which were dementia, the initial medications of prescribing cascades were mainly calcium channel blockers, and two to six drugs were involved in the prescribing cascade routes. Conclusion: Prescribing cascades have attracted more attention internationally and current studies have mainly focused on the elderly and their cardiovascular diseases and nervous diseases, but still not yet formed integral research in other special populations of drug use, such as children and pregnant women. It is necessary to further conduct in-depth studies with a broader range, and to establish a series of effective measures to decrease the incidence of prescribing cascades in the high-risk group of drug use.