Identifying prescribing cascades in Alzheimer's disease and related dementias: The calcium channel blocker-diuretic prescribing cascade

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.

The impact of age, sex, and gender on polypharmacy and potential prescribing cascades: Lessons from five databases

BACKGROUND

Few studies describe how gender-related factors may contribute to polypharmacy and prescribing cascades. Describing these patterns using cross-national comparisons can improve the robustness of findings and provide lessons on the importance of considering age, sex, and gender in pharmacological research. The aim of the study was to explore the intersection of age, sex, and gender with polypharmacy and co-prescribing suggesting a potential prescribing cascade.

METHODS

In this cross-sectional descriptive study, we assessed polypharmacy and calcium channel blocker and diuretic co-prescribing suggesting a prescribing cascade in patients aged ≥65 years from five international secondary databases: population-level community and nursing home (ICES, Maccabi Healthcare Services), clinical trial (SENATOR), and patient registry (Report-AGE, SHELTER). The intersection of age, sex, and gender was explored.

RESULTS

All databases provided age and sex; none included gender-identity data. Gender-related sociocultural factors, socioeconomic status (SES) measured as income and educational attainment, and marital status were not uniformly collected. Compared with males, females had lower income, has less educational attainment, and were more frequently widowed. Polypharmacy was more common in men. Co-prescribing suggesting a prescribing cascade was more frequent in females in four databases and was also more frequent in lower SES and unmarried groups (significant in ICES (community and nursing home) and Maccabi (community), with a nonsignificant trend in Maccabi (nursing home) and three remaining databases). Using two population-level databases, the prevalence of co-prescribing suggesting a prescribing cascade was highest among females 85 years and older who were also in the lower SES group (11.0% ICES and 14.6% Maccabi). Gender disparity was highest in this group (ICES Differential Prevalence = 3.0%, Maccabi Differential Prevalence = 3.8%).

CONCLUSION

Older adults with lower SES experienced polypharmacy or co-prescribing suggesting a prescribing cascade more frequently than those with higher SES. Within the lower SES groups, females more frequently than males had evidence of co-prescribing suggesting a prescribing cascade. Considering the role of sex and gender-related sociocultural factors may help to better understand some contributors to polypharmacy and prescribing cascades. The research applications are highlighted in our five lessons learned.

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.

Developing a PRogram to Educate and Sensitize Caregivers to Reduce the Inappropriate Prescription Burden in the Elderly with Alzheimer's Disease (D-PRESCRIBE-AD): Trial protocol and rationale of an open-label pragmatic, prospective randomized controlled trial

CONTEXT

Potentially inappropriate prescribing of medications in older adults, particular those with dementia, can lead to adverse drug events including falls and fractures, worsening cognitive impairment, emergency department visits, and hospitalizations. Educational mailings from health plans to patients and their providers to encourage deprescribing conversations may represent an effective, low-cost, "light touch", approach to reducing the burden of potentially inappropriate prescription use in older adults with dementia.

OBJECTIVES

The objective of the Developing a PRogram to Educate and Sensitize Caregivers to Reduce the Inappropriate Prescription Burden in Elderly with Alzheimer's Disease (D-PRESCRIBE-AD) trial is to evaluate the effect of a health plan based multi-faceted educational outreach intervention to community dwelling patients with dementia who are currently prescribed sedative/hypnotics, antipsychotics, or strong anticholinergics.

METHODS

The D-PRESCRIBE-AD is an open-label pragmatic, prospective randomized controlled trial (RCT) comparing three arms: 1) educational mailing to both the health plan patient and their prescribing physician (patient plus physician arm, n = 4814); 2) educational mailing to prescribing physician only (physician only arm, n = 4814); and 3) usual care (n = 4814) among patients with dementia enrolled in two large United States based health plans. The primary outcome is the absence of any dispensing of the targeted potentially inappropriate prescription during the 6-month study observation period after a 3-month black out period following the mailing. Secondary outcomes include dose-reduction, polypharmacy, healthcare utilization, mortality and therapeutic switching within targeted drug classes.

CONCLUSION

This large pragmatic RCT will contribute to the evidence base on promoting deprescribing of potentially inappropriate medications among older adults with dementia. If successful, such light touch, inexpensive and highly scalable interventions have the potential to reduce the burden of potentially inappropriate prescribing for patients with dementia. ClinicalTrials.gov Identifier: NCT05147428.

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.

Evaluating Provider and Pharmacy Discordance in Potential Calcium Channel Blocker-Loop Diuretic Prescribing Cascade

BACKGROUND

Prescribing cascades occur when a drug-induced adverse event is treated with a new medication. Identifying clinical scenarios in which prescribing cascades are more likely to occur may help determine ways to prevent prescribing cascades.

OBJECTIVE

To understand the extent to which discordant providers and discordant pharmacies contribute to the dihydropyridine calcium channel blocker (DH CCB)-loop diuretic prescribing cascade.

STUDY POPULATION AND DESIGN

A retrospective cohort study using Medicare Fee-For-Service data (2011-2018) of adults aged ≥ 66 years.

EXPOSURES

Patients who initiated DH CCB with subsequent initiation of loop diuretic (DH CCB-loop diuretic dyad) within 90 days or patients who initiated angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) with subsequent initiation of a loop diuretic (ACEI/ARB-loop diuretic dyad; control).

MAIN OUTCOMES

The primary outcomes were provider and pharmacy discordance for prescribing cascades and control drug pairs. Baseline clinical and socio-demographic characteristics were balanced using inverse probability of treatment weighting with propensity scores.

RESULTS

 Overall, we identified 1987 DH CCB-loop diuretic dyads and 3148 ACEI/ARB-loop diuretic dyads. Discordant providers occurred in 64% of DH CCB-loop diuretic dyads and 55% of ACEI/ARB-loop diuretic dyads, while discordant pharmacies occurred in 19% of DH CCB-loop diuretic dyads and 16% of ACEI/ARB-loop diuretic dyads. After adjustment, the risk of having discordant providers was 20% {Relative Risk (RR) 1.20 [95% confidence interval (CI), 1.14-1.26]} higher in the DH CCB-loop diuretic dyad compared with the ACEI/ARB-loop diuretic dyad. Moreover, pharmacy discordance was 17% (RR 1.17 [95% CI 1.02-1.33]) higher.

CONCLUSION

Our findings suggest that discordant providers and discordant pharmacies were more commonly involved in the potential prescribing cascade when compared with a similar control dyad of medications. Opportunities for enhanced care coordination and medication reconciliation should be explored to prevent unnecessary polypharmacy.

Prescription Sequence Symmetry Analysis (PSSA) to assess prescribing cascades: a step-by-step guide

Prescribing cascades occur when patients are prescribed medication to treat the adverse drug reaction of previously prescribed medication. Prescription sequence symmetry analysis (PSSA) can be used to assess the association between two medications in prescription or dispensing databases and thus the potential occurrence of prescribing cascades. In this article, a step-by-step guide is presented for conducting PSSA to assess prescribing cascades. We describe considerations for medication data collection and setting time periods for relevant parameters, including washout window, exposure window, continued exposure interval and blackout period. With two examples, we illustrate the impact of changes in these parameters on the strengths of associations observed. Given the impact seen, we recommend that researchers clearly specify and explain all considerations regarding medication included and time windows set when studying prescribing cascades with PSSA, and conduct subgroup and sensitivity analyses.

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.

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.

Prescribing cascades in community-dwelling adults: A systematic review

The misattribution of an adverse drug reaction (ADR) as a symptom or illness can lead to the prescribing of additional medication, referred to as a prescribing cascade. The aim of this systematic review is to identify published prescribing cascades in community-dwelling adults. A systematic review was reported in line with the PRISMA guidelines and pre-registered with PROSPERO. Electronic databases (Medline [Ovid], EMBASE, PsycINFO, CINAHL, Cochrane Library) and grey literature sources were searched. Inclusion criteria: community-dwelling adults; risk-prescription medication; outcomes-initiation of new medicine to "treat" or reduce ADR risk; study type-cohort, cross-sectional, case-control, and case-series studies. Title/abstract screening, full-text screening, data extraction, and methodological quality assessment were conducted independently in duplicate. A narrative synthesis was conducted. A total of 101 studies (reported in 103 publications) were included. Study sample sizes ranged from 126 to 11 593 989 participants and 15 studies examined older adults specifically (≥60 years). Seventy-eight of 101 studies reported a potential prescribing cascade including calcium channel blockers to loop diuretic (n = 5), amiodarone to levothyroxine (n = 5), inhaled corticosteroid to topical antifungal (n = 4), antipsychotic to anti-Parkinson drug (n = 4), and acetylcholinesterase inhibitor to urinary incontinence drugs (n = 4). Identified prescribing cascades occurred within three months to one year following initial medication. Methodological quality varied across included studies. Prescribing cascades occur for a broad range of medications. ADRs should be included in the differential diagnosis for patients presenting with new symptoms, particularly older adults and those who started a new medication in the preceding 12 months.

Evaluation of the key prescription sequence symmetry analysis assumption using the calcium channel blocker: Loop diuretic prescribing cascade

OBJECTIVES

To evaluate the prescription sequence symmetry analysis assumption regarding balance between marker drug (i.e., medication used to treat a drug-induced adverse event) initiation rates before and after initiation of an index drug (i.e., medication that is potentially associated with the drug-induced adverse event) in the absence of prescribing cascades, we used a well-described example of loop diuretic initiation to treat dihydropyridine calcium channel blockers (DH CCB)-induced edema.

STUDY DESIGN AND SETTING

The University of Florida Health Integrated Data Repository from June 2011 and July 2018 was used to assess temporal prescribing of DH CCB and loop diuretics within the prescription sequence symmetry analysis framework. Validation of the prescribing cascade was performed via clinical expert chart review.

RESULTS

Among patients without heart failure who were initiated on DH CCB, 26 and 64 loop diuretics initiators started within 360 days before versus after DH CCB initiation, respectively, resulting in an adjusted sequence ratio (aSR) of 2.27 (95% CI, 1.44-3.58). Overall, 35 (54.7%) patients were determined to have a prescribing cascade. Removing patients who experienced a prescribing cascade resulted in an aSR of 1.05, 95% CI 0.62-1.78).

CONCLUSION

Loop diuretic initiation rates before and after DH CCB initiation for reasons other a prescribing cascade were similar, thus confirming the prescription sequence symmetry analysis assumption.

An examination of three prescribing cascades in a cohort of older adults with dementia

BACKGROUND

Prescribing cascades are a source of inappropriate prescribing for older adults with dementia. We aimed to study three prescribing cascades in older Nova Scotians with dementia using administrative databases.

METHODS

Cohort entry for Nova Scotia Seniors' Pharmacare Program beneficiaries was the date of dementia diagnosis. Prescription drug dispensing data was extracted for inciting medication and second treatment (cholinesterase inhibitor and bladder anticholinergic, metoclopramide and Parkinson's disease medication, or calcium channel blocker (CCB) and diuretic) over the six-year period April 1, 2009 to March 31, 2015. In three separate analyses, dispensing an inciting medication signaled a look back of 365 days from the date of first dispensing to confirm that the second treatment was started after the inciting medication. The prescribing cascade was considered when the second treatment was started within 180 days of the inciting treatment. Sex differences in the prescribing cascade were tested using t-tests or chi square tests as appropriate. Both univariate (unadjusted) and multivariate (adjusted) logistic regression (adjusted for age, rurality, and sex) and Cox proportional hazards regression was used to identify risk factors for the prescribing cascade.

RESULTS

From March 1, 2005 to March 31, 2015, 28,953 Nova Scotia Seniors' Pharmacare beneficiaries with dementia (NSSPBD) were identified. There were 60 cases of bladder anticholinergics following cholinesterase inhibitors, 11 cases of Parkinson's disease medication following metoclopramide, and 289 cases of a diuretic following CCB in the cohort. Regression analysis demonstrated that risk of bladder anticholinergics following cholinesterase inhibitors and diuretics following CCBs were associated with female sex. Cox regression suggested that bladder anticholinergics were less often used by those on cholinesterase inhibitors and did not identify CCB use as leading more frequently to diuretic use.

CONCLUSIONS

The combination of diuretics following CCB was the most common prescribing cascade and bladder anticholinergics following cholinesterase inhibitors the second most common. However, exposure to the inciting medications did not increase risk of exposure to the second treatments. Combinations of bladder anticholinergics following cholinesterase inhibitors and diuretics following CCBs were more common for women raising concern that women may be at increased risk of these prescribing cascades.