Patients with a single illness who take many drugs have an increased risk of being admitted to hospital, but for patients with multiple conditions, taking many medicines is now associated with a near-normal risk of admission. This is the key finding of work published in the British Journal of Clinical Pharmacology. Doctors call the situation where people take many drugs 'polypharmacy', a state of affairs that is becoming increasingly common in part because we have more elderly people and also a rising number of people are being diagnosed with multiple health conditions.
"The commonly-held assumption that polypharmacy is always hazardous and represents poor care is misleading. Our work shows that we need more sophisticated approaches to assessing the appropriateness of each patient's set of medicines," says lead author Dr Rupert Payne who works at the Cambridge Centre for Health Services Research.
Working with colleagues in Nottingham and Glasgow, Dr Payne analysed Scottish NHS primary care data for 180,815 adults with long-term clinical conditions. They identified the numbers of regular medications each person was taking and linked this to whether or not the person was admitted to hospital in the following year. They found that for patients with only a single medical condition taking 10 or more medications was associated with a more than three-fold increase in the chance of having an unplanned hospitalisation compared to patients who took only one to three medicines. However, patients with six or more medical conditions who used 10 or more medications only increased their chance of admission by 1.5 times compared to the group taking one to three medicines.
