Examining opioids and benzodiazepines/Z-drugs co-prescribing: a population based cohort study

PI Title: Dr Ruth Jack

Lead Member: University of Nottingham

Background
Opioids are strong medicines taken to relieve pain, and benzodiazepines and Z-drugs are commonly prescribed for insomnia and anxiety. These medicines can have side effects and lead to addiction problems. There are also concerns that taking both
medicines at the same time can lead to severe problems including increased risks of overdose, emergency hospital visits, and death. Some countries have issued safety alerts advising that these medicines should not be taken at the same time. Despite
this, there is evidence that the numbers of people prescribed both medicines to be taken together have increased in the last 20 years. It is recommended in the UK that these medicines should only be prescribed at the same time if there is no
alternative, but there is little information on how often the medicines are prescribed together in the UK nor on whether this has changed over time.

Research questions
We want to find out how often people have prescriptions from GPs for opioids that overlap with prescriptions for benzodiazepines or Z-drugs (called “co-prescribing”), and whether this has changed over time. We also want to see whether
certain groups of people, such as those from deprived areas, are more likely to be prescribed both types of medicine together. This information will help GPs, policymakers, and other researchers understand how many people in England may
be at risk of harm from using both types of medicines at the same time. It will also help researchers design future studies about the safety of using these two medicines together.

What will we do?
We will use existing information from a research database called the Clinical Practice Research Datalink (CPRD). This contains anonymised electronic health records collected in general practices in the UK. We will identify people who were prescribed
opioids, benzodiazepines and Z-drugs between 2011 and 2023 and work out whether these prescriptions overlapped. To see whether different groups of people are more likely to have these medicines co-prescribed we will look at the sex, age, ethnic
group of the people, as well as the level of deprivation and region where they live.

Patient and public involvement (PPI)
Our public contributor co-applicant had the original research question about people taking multiple different medicines.
Public contributors will be part of the project team and join project meetings to discuss the progress of the research and next steps.

Dissemination
We will write up the results for publication in a scientific journal and present the results at a conference. We will share the results with the public and health professionals using social media, patient participation groups and professional networks,
following advice from our public contributors.