Ontario-Wide Study Identifies 24 Common Prescribing Cascades Driving Drug Harm in Older Adults
核心洞察
An Ontario-wide study published in BMJ identified 24 potentially inappropriate prescribing cascades that are common in the population and carry potential for harm.
Prescribing cascades occur when a drug's side effect is mistaken for a new condition, prompting an unnecessary additional prescription, such as NSAID-induced blood pressure rises treated with antihypertensives.
Researchers screened 65 previously defined cascades against ICES (搜索) population prescription data using three measures: initial drug frequency, likelihood of a follow-on prescription, and strength of the link.
An Ontario-wide study has identified 24 potentially inappropriate prescribing cascades (PIPCs) that are commonly observed in the population and carry the potential to cause harm, according to research published in BMJ and led by Dr. Paula Rochon, Director of Research at the Weston and O'Born Centre for Mature Women's Health at Sinai Health (搜索) in Toronto.
A PIPC occurs when a medication's side effect is mistaken for a new health problem, leading to another prescription that may not have been needed in the first place. The study's authors describe these drug combinations as a common but unrecognized contributor to drug-related harm at the population level, adding unnecessary costs to the healthcare system.
From 65 Candidate Cascades to 24 Priority Signals
The research team, an interdisciplinary international collaboration with experts from the United States, Belgium, Italy, Israel and Ireland, had previously drawn on the expertise of 12 international panelists specializing in internal medicine, geriatric medicine and clinical pharmacology to create a list of 65 PIPCs. The Sinai Health (搜索) team included Drs. Vasily Giannakeas, Nathan Stall and Christina Reppas-Rindlisbacher, along with research staff Wei Wu and Joyce Li.
For the new analysis, that list was examined against population-level prescription data from ICES (搜索), Ontario's health data institute, with work by Lavina Matai and Zhiyin Li. Each PIPC was evaluated against three factors: how common the initial drug was in the population, how often it was followed by the second drug, and how strong the link was between the two. That analysis allowed the researchers to pinpoint the 24 cascades most commonly seen in the population and with a potential to cause harm.
NSAIDs as a Model Cascade
One common example flagged in the study involves non-steroidal anti-inflammatory drugs (搜索) (NSAIDs). Commonly prescribed for pain, these drugs are associated with a rise in blood pressure, which can lead to a new prescription for high blood pressure (搜索) rather than a second look at the original pain medication. The study also names statins (搜索) and iron supplements (搜索) among the widely used medications that can set off these sequences.
Older adults are especially vulnerable to the pattern because they are more likely to be on multiple medications at once due to having multiple conditions, making it harder for both patients and clinicians to trace a new symptom back to an existing drug.
"These sequences of events are common but often missed in clinical practice," said Dr. Rochon, who holds the Barry J. Goldlist Chair in Aging and Health at Sinai Health (搜索) and is also a professor of medicine at the University of Toronto. "Knowing what medications you are taking, when they were started and for what indication is important in order to identify possible prescribing cascades that may be problematic."
A Communication Gap That Opens One Prescription at a Time
For Dr. Rochon, the findings highlight a gap that opens quietly, one prescription at a time. "Our concern is that so often these conversations between the health care prescriber and the patient are being missed, so people don't recognize the sequences of events and that they are connected to one another," she said.
Closing that gap means physicians need to think about medication history at every visit — not just what a patient is currently taking, but why each drug was started in the first place, and whether the next one was really needed.
Particular Weight for Mature Women
The work carries particular weight for mature women, who tend to live with more chronic conditions than men over their lifetime. Mature women are prescribed more drug therapies and experience more adverse drug events. By being on multiple medications at once, they are more exposed to the risk that a drug's side effect gets mistaken for a new diagnosis rather than traced back to its source.
Technology and Pharmacists as Detection Points
The researchers say technology could provide one way to reduce these potentially harmful prescribing patterns. Automated clinical decision support systems could be designed to recognize a possible prescribing cascade as it develops, alerting clinicians when a new medication appears to be treating a known side effect of an existing drug and giving them an opportunity to reconsider the treatment plan before adding another prescription. This information could be incorporated into several types of automated tools that alert clinicians to PIPCs at the point of care.
The researchers also see an opportunity to make greater use of pharmacists as part of the healthcare team. More directly involving pharmacists in prescribing decisions alongside physicians could help uncover medication patterns that might otherwise go unnoticed, with their expertise helping identify PIPCs that warrant further evaluation.