Stopping concurrent benzodiazepine and opioid prescribing could reduce the risk of inpatient admissions for opioid overdose and attendance at emergency departments by 15%, a study from the US has found.

To assess trends in joint prescribing and their impact on hospital admissions and emergency room visits for opioid overdose, the researchers, analysed concurrent prescribing data for benzodiazepines and an opioid between 2001 and 2013. Health data were obtained from a large, broadly representative, privately insured population. Concurrent was defined as at least one day of overlap in the period covered by each prescription.

During the study period 315,428 patients in the sample population had received at least one prescription for an opioid medication. Of those prescribed an opioid, 5,425 out of 53,389 (9%) were also prescribed a benzodiazepine during 2001. This had risen to 14,415 out of 85,617 (17%) in 2013, an increase of 80%.

The increase was primarily within intermittent, rather than chronic, opioid users. In intermittent users, the percentage who also used a benzodiazepine rose from 7% to 13% over the study period.

Compared with opioid users who were not prescribed benzodiazepines concurrent use of both drugs was associated with double the risk of attending an emergency room, or being admitted, for opioid overdose adjusted odds ratio (OR) 2.14 (95% CI: 2.05-2.24; P < 0.001). The adjusted OR for an emergency room visit or admission for opioid overdose was 1.42 (95% CI: 1.33-1.51; P < 0.001) for intermittent opioid users and 1.81 (95% CI: 1.67-1.96; P < 0.001) for regular opioid users.

This study has identified a sharp increase in concurrent benzodiazepine and opioid prescribing in the US between 2001 and 2013 in a representative population.

This increase may have contributed significantly to the risk of opioid overdose needing either emergency room attendance or hospital admission.

Assuming a causal relationship, the authors estimated that stopping concurrent benzodiazepine and opioid prescribing could reduce the risk of emergency room attendance and inpatient admissions for opioid overdose by 15% (95% CI: 14-16%).

Doctors are much more likely than they were to prescribe long-term opioid analgesics for non-cancer pain. In the US opioid prescriptions have increased almost three fold over the past 15 years and prescribing in the UK has also been increasing.¹

Some fear an ‘epidemic’ of opioid prescribing in the UK to match the North American experience, with consequent increases in dependence and opioid-related overdoses and deaths.

Nearly 30% of fatal opioid overdoses in the US also involved benzodiazepine use, where the benzodiazepine may have potentiated the respiratory depression effect of the opioid.

The study authors conclude: ‘Providers should exercise caution in prescribing opioids for patients who are already using benzodiazepines (or vice versa), even in a non-chronic setting. Indeed, we note that the association between concurrent benzodiazepine/opioid use and the risk of opioid overdose was broadly similar for both intermittent and chronic opioid users. Therefore, opioids should be prescribed cautiously – even if only for a short-term course – among patients who are also using benzodiazepines.’

‘Healthcare providers might also want to implement education programs that warn prescribers and patients about the risks of taking benzodiazepines and opioids concurrently,’ they add.

Dr Jez Thompson