Pain and pain prescribing: what is in a number?

Healthcare resource utilisation and cost analysis associated with opioid analgesic use for non-cancer pain: A case-control, retrospective study between 2005 and 2015

Objective

To examine differences in healthcare utilisation and costs associated with opioid prescriptions for non-cancer pain issued in primary care.

Method

A longitudinal, case-control study retrospectively examined Welsh healthcare data for the period 1 January 2005–31 December 2015. Data were extracted from the Secure Anonymised Information Linkage (SAIL) databank. Subjects, aged 18 years and over, were included if their primary care record contained at least one of six overarching pain diagnoses during the study period. Subjects were excluded if their record also contained a cancer diagnosis in that time or the year prior to the study period. Case subjects also received at least one prescription for an opioid analgesic. Controls were matched by gender, age, pain-diagnosis and socioeconomic deprivation. Healthcare use included primary care visits, emergency department (ED) and outpatient (OPD) attendances, inpatient (IP) admissions and length of stay. Cost analysis for healthcare utilisation used nationally derived unit costs for 2015. Differences between case and control subjects for resource use and costs were analysed and further stratified by gender, prescribing persistence (PP) and deprivation.

Results

Data from 3,286,215 individuals were examined with 657,243 receiving opioids. Case subjects averaged 5 times more primary care visits, 2.8 times more OPD attendances, 3 times more ED visits and twice as many IN admissions as controls. Prescription persistence over 6 months and greater deprivation were associated with significantly greater utilisation of healthcare resources. Opioid prescribing was associated with 69% greater average healthcare costs than in control subjects. National Health Service (NHS) healthcare service costs for people with common, pain-associated diagnoses, receiving opioid analgesics were estimated to be £0.9billion per year between 2005 and 2015.

Conclusion

Receipt of opioid prescriptions was associated with significantly greater healthcare utilisation and accompanying costs in all sectors. Extended prescribing durations are particularly important to address and should be considered at the point of initiation.

Examining opioid prescribing trends for non-cancer pain using an estimated oral morphine equivalence measure: a retrospective cohort study between 2005 and 2015

Background

Over the past 20 years prescription of opioid medicines has markedly increased in the UK, despite a lack of supporting evidence for use in commonly occurring, painful conditions. Prescribing is often monitored by counting numbers of prescriptions dispensed, but this may not provide an accurate picture of clinical practice.

Aim

To use an estimated oral morphine equivalent (OMEQ_e) dose to describe trends in opioid prescribing in non-cancer pain, and explore if opioid burden differed by deprivation status.

Design & setting

A retrospective cohort study using cross-sectional and longitudinal trend analyses of opioid prescribing data from Welsh Primary Care General Practices (PCGP) took place. Data were used from the Secure Anonymised Information Linkage (SAIL) databank.

Method

An OMEQ_e measure was developed and used to describe trends in opioid burden over the study period. OMEQ_e burden was stratified by eight drug groups, which was based on usage and deprivation.

Results

An estimated 643 436 843 milligrams (mg) OMEQ_e was issued during the study. Annual number of prescriptions increased 44% between 2005 and 2015, while total daily OMEQ_e per 1000 population increased by 95%. The most deprived areas of Wales had 100 711 696 mg more OMEQ_e prescribed than the least deprived over the study period.

Conclusion

Over the study period, OMEQ_e burden nearly doubled, with disproportionate OMEQ_e prescribed in the most deprived communities. Using OMEQ_e provides an alternative measure of prescribing and allows easier comparison of the contribution different drugs make to the overall opioid burden.

Factors associated with the prescribing of high-dose opioids in primary care: a systematic review and meta-analysis

BACKGROUND

The risks of harms from opioids increase substantially at high doses, and high-dose prescribing has increased in primary care. However, little is known about what leads to high-dose prescribing, and studies exploring this have not been synthesized. We, therefore, systematically synthesized factors associated with the prescribing of high-dose opioids in primary care.

METHODS

We conducted a systematic review of observational studies in high-income countries that used patient-level primary care data and explored any factor(s) in people for whom opioids were prescribed, stratified by oral morphine equivalents (OME). We defined high doses as ≥ 90 OME mg/day. We searched MEDLINE, Embase, Web of Science, reference lists, forward citations, and conference proceedings from database inception to 5 April 2019. Two investigators independently screened studies, extracted data, and appraised the quality of included studies using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. We pooled data on factors using random effects meta-analyses and reported relative risks (RR) or mean differences with 95% confidence intervals (CI) where appropriate. We also performed a number needed to harm (NNT_H) calculation on factors when applicable.

RESULTS

We included six studies with a total of 4,248,119 participants taking opioids, of whom 3.64% (n = 154,749) were taking high doses. The majority of included studies (n = 4) were conducted in the USA, one in Australia and one in the UK. The largest study (n = 4,046,275) was from the USA. Included studies were graded as having fair to good quality evidence. The co-prescription of benzodiazepines (RR 3.27, 95% CI 1.32 to 8.13, I² = 99.9%), depression (RR 1.38, 95% CI 1.27 to 1.51, I² = 0%), emergency department visits (RR 1.53, 95% CI 1.46 to 1.61, I² = 0%, NNT_H 15, 95% CI 12 to 20), unemployment (RR 1.44, 95% CI 1.27 to 1.63, I² = 0%), and male gender (RR 1.21, 95% CI 1.14 to 1.28, I² = 78.6%) were significantly associated with the prescribing of high-dose opioids in primary care.

CONCLUSIONS

High doses of opioids are associated with greater risks of harms. Associated factors such as the co-prescription of benzodiazepines and depression identify priority areas that should be considered when selecting, identifying, and managing people taking high-dose opioids in primary care. Coordinated strategies and services that promote the safe prescribing of opioids are needed.

STUDY REGISTRATION

PROSPERO, CRD42018088057.