image: Prescribing Cascades Among Older Community-Dwelling Adults: Application of Prescription Sequence Symmetry Analysis to a National Database in Ireland
Credit: American Academy of Family Physicians
Background and Goal: “Prescribing cascades” occur when one medication is used to treat or prevent a side effect of another medication. An unintentional cascade can arise when a patient's symptoms are mistaken for a new illness. In that case, the patient not only experiences the original side effect but also faces added risks from the second medication.
Study Approach: Researchers at University College Cork in Cork, Ireland, analyzed national prescription data for 533,464 community-dwelling Irish adults aged 65 years and older, covering prescriptions dispensed from 2017 to 2020. A prescription sequence symmetry analysis was performed with a 365-day window to examine nine expert-defined prescribing cascades known as “ThinkCascades.” Researchers examined dispensed prescriptions data only for potential prescribing cascades.
Main Results:
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Out of the nine prescribing cascades examined, five had significant positive adjusted sequence ratios, indicating that the patient was more likely to receive the first medication before the second medication:
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Calcium channel blocker leading to diuretic prescribing
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Alpha-1-receptor blocker leading to vestibular sedative prescribing
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Selective serotonin reuptake inhibitor (SSRI) or selective norepinephrine reuptake inhibitor (SNRI) leading to sleep agent prescribing
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Benzodiazepine leading to antipsychotic prescribing
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Antipsychotic leading to antiParkinsonian agent prescribing
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Three other drug pairs showed significant negative associations, indicating that the patient was less likely to receive the first medication before the second medication:
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Diuretic to overactive bladder medication
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Benzodiazepine to antidementia agent
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Nonsteroidal anti-inflammatory drugs (NSAIDs) to antihypertensive medication
Why It Matters: For clinicians, including adverse drug reactions among the possible causes to confirm or exclude when patients present with new symptoms in primary care is an important step in identifying and mitigating medication-related harm.
Ann Sinéad Doherty, PhD, et al
Department of General Practice, School of Medicine, University College Cork, Cork, Ireland
An accompanying episode of the Annals of Family Medicine Podcast, featuring study authors Ann Sinéad Doherty, PhD, and Emma Wallace, PhD, will be available at 9 a.m. ET on July 29, 2025 [here].
This study has been published as an early access article on the Annals of Family Medicine website. Please share the link associated with the title text of the study (this one: Prescribing Cascades Among Older Community-Dwelling Adults: Application of Prescription Sequence Symmetry Analysis to a National Database in Ireland)
Journal
The Annals of Family Medicine