Patients on 10 or more prescribed drugs are at greater risk of prescribing errors.
An audit has been conducted at one of the largest general practices in North London serving a population of 20,000 patients to determine the extent of this so-called ‘polypharmacy’.
Doctors hope to identify patients whose prescriptions could be optimised to decrease their risk of adverse events with a view to empowering and encouraging other healthcare professionals to also think about when it is appropriate to stop medication. Many people, especially elderly people, need multiple medications for several concurrent conditions.
“Data shows that patients can handleup to 10 drugs but problems are much more likely to occur with more than 10. No one is quite sure why. It could be because patients forget, doctors may make errors when patients are repeatedly admitted to hospital, or patients may simply ignore their medications,” said Selma Audi, a student from St George’s Hospital, London.
As well as a 47% increased risk of error from prescribing 10 or more prescriptions, there is also an increased risk of adverse effects due to the drugs interacting with each other.
Speaking at Pharmacology 2015, Ms Audi explained that she carried out an audit of data for 584 patients at the James Wigg GP practice in Camden, each receiving ten or more prescriptions – a total of 18,289 prescriptions. Of these, 427 patients (254 female and 173 male) were currently on repeat prescriptions. She then investigated these 5,321 prescriptions.
Most of the people over 50 years of age were being repeatedly prescribed analgesics. In patients in the 50-74 age range, drugs for diabetes accounted for the second largest category of repeat prescriptions. Just over 20% of all prescriptions were for heart and circulatory disease in those over 75, with analgesics being the largest category of repeat prescriptions. Because of the high rate of heart disease in the elderly, this may reflect appropriate polypharmacy and represent best practice prescribing. However, the scale of analgesic use in older people is potentially harmful.
“Most clinical trials are conducted in younger people with single diseases, not multiple diseases,” said Ms Audi, health economist and a medical student. “We simply do not have enough information on the cumulative effects of multiple drugs, particularly in the elderly,” she told delegates at the British Pharmacological Society’s annual meeting, in London.
The next phase is to establish best practice and the threshold at which excessive polypharmacy might cause adverse reactions. To do this, doctors will invite priority patients for an extended appointment. During this consultation, the patient’s needs and treatment regime will be reviewed, and their compliance and understanding of the effects of the different medication will be checked. They will also consider de-prescribing drugs that are no longer beneficial and may indeed causing harm.
“Patients will be asked whether they prefer taking, for example, a tablet or liquid form of their medicine and also whether they need further help with taking their medication. For example, are the bottles easy to open? We will also establish if they can be directed to their pharmacist for further assistance,” she said.
In the future, the team hopes this approach will improve patient safety and satisfaction with care.
