Prescription opioid dispensing in New South Wales, Australia: spatial and temporal variation

Sex differences in patterns of potentially inappropriate prescribing and adverse drug reactions in hospitalized older people: Findings from the SENATOR trial

BACKGROUND

Older women experience more adverse drug reactions (ADRs) than older men. However, the underlying basis for this sex difference is unclear. Sex (biological status) and/or gender (sociocultural constructs) influences on patterns of inappropriate prescribing in multimorbid older adults may be one reason for this ADR sex difference. In this secondary analysis, we examined whether incident ADR sex differences could be related to concurrent sex differences in potentially inappropriate prescribing.

DESIGN AND SETTING

A retrospective secondary analysis of sex differences in the prevalence of potentially inappropriate medications (PIMs), potential prescribing omissions (PPOs), and ADRs among the 1537 participants (47.2% female, median [IQR] age 78 [72-84] years) was undertaken in the SENATOR clinical trial database, conducted in six large European medical centers.

PARTICIPANTS AND METHODS

We looked specifically for male/female differences relating to PIMs and PPOs (defined by STOPP/START version 2 criteria) identified within 48 h of acute hospitalization. We also assessed sex differences for ADRs identified at 14 days from admission or discharge, whichever came first. ADRs were assessed by blinded endpoint adjudication panel consensus.

RESULTS

During hospitalization, significantly more females experienced ≥1 ADR compared to males (28% and 21%, respectively; odds ratio 1.40, 95% CI 1.10-1.78, p < 0.005). Nine of the 11 STOPP-criteria PIMs showing a significant sex difference occurred more often in females. Of the four START-criteria PPOs showing a significant sex difference, all occurred more often in females. Some sex-associated PIMs reflect higher prevalence of related conditions in older women.

CONCLUSION

We conclude that specific STOPP-criteria PIMs and START-criteria PPOs were identified more frequently in older women than older men during acute hospitalization, possibly contributing to higher ADR incidence in older women. Prescribers should appreciate sex differences in exposure to potentially inappropriate prescribing and ADR risk, given the preponderance of older women over older men in most clinical settings.

Monitoring medication and illicit drug consumption in a prison by wastewater-based epidemiology: Impact of COVID-19 restrictions

Drug consumption in prisons is a concern for the safety of incarcerated people and staff. Typically, drug use prevalence in prisons is estimated through urinalysis and intelligence operations, which can be intrusive and stressful. An alternative approach, wastewater-based epidemiology (WBE), was used in this study to estimate the consumption of licit and illicit drugs for the entire population of a prison in Australia. Wastewater samples were collected from March to December 2020, covering periods of no restrictions and periods when prison access was restricted to prevent the transmission of COVID-19. Target biomarkers were analysed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The average consumption of common illicit drugs (MDMA, methamphetamine and cocaine) over the sampling period in the prison (0.5 - 4.5 mg/1000 people/day) was two to three orders of magnitude lower than in the community population (254 - 1000 mg/1000 people/day). Comparison of WBE estimates against pharmacy dispensing data suggested potential illicit buprenorphine consumption at the prison. Methamphetamine and buprenorphine use decreased when no visitors were allowed (18% - 72% decrease for methamphetamine; about half decrease for buprenorphine) and increased once these restrictions were eased (22% - 39% increase for methamphetamine; 44% - 67% increase for buprenorphine). The changes in drug use may be attributed in part to a reduction of drug trafficking into the prison from visitors or non-essential staffs and in part to the reduced contribution of urine from staff who used toilets within the prison. This study provided useful information on the scale of illicit drug use and extra-medical use of licit drugs in prison, and its changes under different security conditions.

Patterns of real-world opioid prescribing in Australian general practice (2013-18)

Little is known about private-market opioid prescribing and how Australian opioid policies impact prescribing across public and private markets in Australia. We aimed to investigate publicly subsidised and private-market opioid prescribing from 2013 to 2018. We used prescribing records from MedicineInsight, an Australian primary care database, to examine trends in prescriptions for non-injectable opioid formulations from October 2013 to September 2018. We examined annual opioid prescribing trends overall, by opioid agent, and by market (public and private). We further examined patterns of fentanyl patch prescribing focusing on co-prescribed medicines and use in opioid-naïve patients. Opioids accounted for 8% of all prescriptions over the study period and 468 893 patients were prescribed at least one opioid of interest. Prescribing rates for oxycodone/naloxone and tapentadol increased, whereas those for fentanyl patches, morphine and single-agent oxycodone decreased over the study period. Private-market prescribing rates of codeine (schedule 4) increased notably following its up-scheduling to prescription-only status. Among patients prescribed fentanyl patches, 29% were potentially opioid-naïve and 49% were prescribed another opioid on the same day. The private-medicines market is a small but growing component of opioid use in Australia and one way in which prescribers and patients can avoid access restrictions in the public market for these medicines. Although fentanyl patch prescribing declined, there is room for improvement in prescribing fentanyl patches among opioid-naïve patients, and co-prescribing of fentanyl patches with other sedatives.

Endogenous opiates and behavior: 2019

This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Trends in long-term opioid prescriptions for musculoskeletal conditions in Australian general practice: a national longitudinal study using MedicineInsight, 2012-2018

OBJECTIVE

Describe trends and patterns in long-term opioid prescriptions among adults with musculoskeletal conditions (MSK).

DESIGN

Interrupted time-series analysis based on an open cohort study.

SETTING

A representative sample of 402 Australian general practices contributing data to the MedicineInsight database.

PARTICIPANTS

811 174 patients aged 18+ years with an MSK diagnosis and three or more consultations in any two consecutive years between 2012 and 2018. Males represented 44.5% of the sample, 28.4% were 65+ years and 1.9% were Aboriginal or Torres Strait Islanders.

PRIMARY AND SECONDARY OUTCOME MEASURES

Annual prevalence and cumulative incidence (%) of long-term opioid prescribing (3+ prescriptions in 90 days) among patients with an MSK. Average duration of these episodes in each year between 2012 and 2018.

RESULTS

The prevalence of long-term opioid prescribing increased from 5.5% (95% CI 5.2 to 5.8) in 2012 to 9.1% (95% CI 8.8 to 9.7) in 2018 (annual change OR 1.09, 95% CI 1.08 to 1.09), but a slightly lower incidence was observed in 2018 (3.0% vs 3.6%-3.8% in other years; annual change OR 0.99, 95% CI 0.98 to 0.99). The incidence was between 37% and 52% higher among practices located in rural Australia or lower socioeconomic areas. Individual risk factors included increasing age (3.4 times higher among those aged 80+ years than the 18-34 years group in 2012, increasing to 4.8 times higher in 2018), identifying as Aboriginal or Torres Strait Islander (1.7-1.9 higher incidence than their peers), or living in disadvantaged areas (36%-57% more likely than among those living in wealthiest areas). Long-term opioid prescriptions lasted in average 287-301 days between 2012 and 2016, reducing to 229 days in 2017 and 140 days in 2018. A longer duration was observed in practices from more disadvantaged areas and females in all years, except in 2018.

CONCLUSIONS

The continued rise in the prevalence of long-term opioid prescribing is of concern, despite a recent reduction in the incidence and duration of opioid management.

Trends in opioid prescribing in Australia: a systematic review

Objective This review systematically identified studies that estimated the prevalence of prescription opioid use in Australia, assessed the prevalence estimates for bias and identified areas for future research. Methods Literature published after 2000 containing a potentially representative estimate of prescription opioid use in adults, in the community setting, in Australia was included in this review. Studies that solely assessed opioid replacement, illicit opioid usage or acute hospital in-patient use were excluded. Databases searched included PubMed, EMBASE, Web of Science and the grey literature. Results The search identified 2253 peer-reviewed publications, with 34 requiring full-text review. Of these, 20 were included in the final qualitative analysis, in addition to four publications from the grey literature. Most studies included analysed prescription claims data for medicines dispensed via Australia's national medicines subsidy scheme (the Pharmaceutical Benefits Scheme). Although data sources were good quality, all prevalence estimates were at least at moderate risk of bias, predominantly due to incompleteness of data or potential confounding. Included publications demonstrated a significant rise in opioid use up to 2017 (including a 15-fold increase in prescriptions dispensed over the 20 years to 2015), predominantly driven by a sharp rise in oxycodone use. Although opioid prescription numbers continue to escalate, usage, as measured by oral morphine equivalent per capita, may have plateaued since 2014. Codeine remains the most prevalently obtained opioid, followed by oxycodone and tramadol. There was a substantial delay (median 30 months; interquartile range 20-37 months) to publication of opioid usage data from time of availability. Conclusions Australia has experienced a marked increase in opioid prescribing since the 1990s. Current published literature is restricted to incomplete, delayed and historical data, limiting the ability of clinicians and policy makers to intervene appropriately. What is known about the topic? Opioid prescriptions in Australia have continued to increase since the 1990s and may be mirroring the epidemic being seen in the US. What does this paper add? This paper systematically identifies all publications that have examined the prevalence of prescription opioid use in Australia since 2000, and only identified prevalence estimates that were at moderate or high risk of bias, and found significant delays to publication of these estimates. What are the implications for practitioners? Because published literature on the prevalence of prescription opioid consumption is restricted to incomplete, delayed and historical data, the ability of clinicians and policy makers to appropriately intervene to curb prescription opioid use is limited. A national policy of real-time monitoring and reporting of opioid prescribing may support improvements in practice.

Inequalities in prescription rates of anti-osteoporosis drugs in primary care in England: A practice-level prescribing data analysis in 2013-2018

OBJECTIVE

To investigate potential variations in prescription rates of anti-osteoporosis drugs at the general practitioner (GP) practice level in England, analysing associations of prescription rates with key demographic and socio-economic variables, and its evolution over time.

METHODS

A retrospective database analysis was conducted using prescription data from all GP practices in England between April 2013 and September 2018. Potential associations between prescription rates and other variables (sex, age, ethnicity, rural-urban classification and income deprivation) were analysed using mixed-effects Poisson regressions and concentration indices.

RESULTS

Alendronic acid was the most frequently prescribed anti-osteoporosis drug. Exploratory and regression analyses showed the association between GP prescriptions and the characteristics of the population they serve. Income deprivation had a statistically significant and negative effect on prescription levels of alendronic acid, denosumab, ibandronic acid and risedronate sodium. Since 2013, denosumab prescriptions exhibited a steep surge in the least income-deprived areas, compared with a modest rise in the most income-deprived areas. Concentration indices indicated a disproportionate concentration of denosumab and, to a lesser extent, ibandronic acid prescriptions among the least income-deprived. The analyses demonstrated that different prescribing behaviours may exist across GPs according to the Clinical Commissioning Group (CCG) to which they belong.

CONCLUSIONS

Variation in the prescription of anti-osteoporosis drugs exists across GPs and CCGs in England, this being more prominent for certain drugs (e.g. denosumab) compared with others (e.g. alendronic acid). Inequalities exist in English primary healthcare and we advocate our findings could support the efforts of decision-makers towards a more equitable system.

Suspected heroin-related overdoses incidents in Cincinnati, Ohio: A spatiotemporal analysis

BACKGROUND

Opioid misuse and deaths are increasing in the United States. In 2017, Ohio had the second highest overdose rates in the US, with the city of Cincinnati experiencing a 50% rise in opioid overdoses since 2015. Understanding the temporal and geographic variation in overdose emergencies may help guide public policy responses to the opioid epidemic.

METHODS AND FINDINGS

We used a publicly available data set of suspected heroin-related emergency calls (n = 6,246) to map overdose incidents to 280 census block groups in Cincinnati between August 1, 2015, and January 30, 2019. We used a Bayesian space-time Poisson regression model to examine the relationship between demographic and environmental characteristics and the number of calls within block groups. Higher numbers of heroin-related incidents were found to be associated with features of the built environment, including the proportion of parks (relative risk [RR] = 2.233; 95% credible interval [CI]: [1.075-4.643]), commercial (RR = 13.200; 95% CI: [4.584-38.169]), manufacturing (RR = 4.775; 95% CI: [1.958-11.683]), and downtown development zones (RR = 11.362; 95% CI: [3.796-34.015]). The number of suspected heroin-related emergency calls was also positively associated with the proportion of male population, the population aged 35-49 years, and distance to pharmacies and was negatively associated with the proportion aged 18-24 years, the proportion of the population with a bachelor's degree or higher, median household income, the number of fast food restaurants, distance to hospitals, and distance to opioid treatment programs. Significant spatial and temporal heterogeneity in the risks of incidents remained after adjusting for covariates. Limitations of this study include lack of information about the nature of incidents after dispatch, which may differ from the initial classification of being related to heroin, and lack of information on local policy changes and interventions.

CONCLUSIONS

We identified areas with high numbers of reported heroin-related incidents and features of the built environment and demographic characteristics that are associated with these events in the city of Cincinnati. Publicly available information about opiate overdoses, combined with data on spatiotemporal risk factors, may help municipalities plan, implement, and target harm-reduction measures. In the US, more work is necessary to improve data availability in other cities and states and the compatibility of data from different sources in order to adequately measure and monitor the risk of overdose and inform health policies.

Adverse drug reactions due to opioid analgesic use in New South Wales, Australia: a spatial-temporal analysis

Background

Pharmaceutical opioid analgesic use continues to rise and is associated with potentially preventable harm including hospitalisation for adverse drug reactions (ADRs). Spatial detection of opioid-related ADRs can inform future intervention strategies. We aimed to investigate the geographical disparity in hospitalised ADRs related to opioid analgesic use, and to evaluate the difference in patient characteristics between areas inside and outside the geographic clusters.

Methods

We used the all-inclusive Admitted Patient Dataset for an Australian state (New South Wales, NSW) to identify patients admitted for opioid-related ADRs over a 10-year period (July 2004 to June 2014). A space-time analysis was conducted using Kulldroff’s scan statistics to identify statistically significant spatial clusters over time. Relative risk (RR) was computed with p-value based on Monte Carlo Simulation. Chi-square test was used to compare proportional difference in patient clustering.

Results

During the study period, we identified four statistically significant geographic clusters (RRs: 1.63–2.17) during 2004–08; and seven clusters (RRs: 1.23–1.69) during the period 2009–14. While identified high-risk clusters primarily covered areas with easier access to health services, those associated with socioeconomically disadvantaged areas and individuals with mental health disorders experienced more unmet healthcare needs for opioid analgesic safety than those from the rest of the State. Older people (≥65 years and over) accounted for 62.7% of the total study population and were more susceptible to opioid-related ADRs than younger people,. In the first five-year period the clusters included a greater proportion of people with cancer in contrast to the second five-year period in which there was a lesser proportion of people with cancer.

Conclusions

These results suggest that there is significant spatial-temporal variation in opioid-related ADRs and future interventions should target vulnerable populations and high-risk geographical areas to improve safer use of pharmaceutical opioid analgesics.

A comparison of opioids and benzodiazepines dispensing in Australia

Background

Inappropriate utilization of prescription opioids and benzodiazepines is a public health problem. This study examined and compared user-types and trends in dispensing of these medicines, and identified associated factors related to the duration of dispensing in Australia.

Methods

A random 10% sample of unit-record data of opioids and benzodiazepines dispensed nationally during 2013–2016 was analyzed. Users were categorized into four types: single-quarter (i.e., three months), medium-episodic (dispensed 2–6 quarters), long-episodic (dispensed 7–11 quarters), chronic (dispensed 12–16 quarters). Dispensing quantity was computed in defined daily dose (DDD). Generalized multilevel ordinal models were developed to examine the factors associated with the duration of dispensing.

Results

There were similarities in terms of trends of dispensing of opioids and benzodiazepines in Australia. Overall, more people were dispensed opioids than benzodiazepines. Around 52% of opioids users and 46% of benzodiazepines users were dispensed these medicines for a single quarter. However, chronic users were dispensed 60% of opioids and 50% of benzodiazepines in DDD/1000 people/day, respectively. On average, 16.6 DDD/1000 people/day of opioids and 14.2 DDD/1000 people/day of benzodiazepines were dispensed in Australia during the study period. Tasmania was dispensed the highest quantity (in DDD/1000 people/day) of these medicines, followed by South Australia and Queensland. Women compared to men, and clients of age-group 20–44, 45–64 and 65+ compared to age-group 0–19, were significantly more likely to have dispensed opioids/benzodiazepine for a relatively long duration. Clients with a history of dispensing of one of these two medicines were significantly more likely to have dispensed the other for a relatively long period.

Conclusions

There were similarities in patterns of dispensing of opioids and benzodiazepines in terms of user characteristics and structural variables. Consistent use of real-time drug monitoring program and tailored intervention are recommended.

Who Are Dispensed the Bulk Amount of Prescription Opioids?

Background: Excessive and non-medical use of prescription opioids is a public health crisis in many settings. This study examined the distribution of user types based on duration of use, trends in and associated factors of dispensing of prescription opioids in New South Wales and Victoria, Australia. Methods: 10% sample of unit-record data of four-year dispensing of prescription opioids was analysed. Quantities dispensed were computed in defined daily dose (DDD). Multilevel models examined factors associated with the duration of dispensing and the quantity dispensed in local government areas. Results: Overall, 53% were single-quarter, 37.3% medium-episodic (dispensed 2–6 quarters), 5% long-episodic (dispensed 7–11 quarters) and 5% were chronic users (dispensed 12–14 quarters). More than 80% of opioids in terms of DDD/1000 people/day were dispensed to long-episodic and chronic users. Codeine and oxycodone were most popular items—both in terms of number of users and quantity dispensed. Duration of dispensing was significantly higher for women than men. Dispensing quantity and duration increased with increasing age and residence in relatively poor neighborhoods. Conclusions: Although only 5% were chronic users, almost 60% of opioids (in DDD/1000 people/day) were dispensed to them. Given that chronic use is linked to adverse health outcomes, and there is a progression toward chronic use, tailored interventions are required for each type of users.

Variation in Prescription Opioid Dispensing across Neighborhoods of Diverse Socioeconomic Disadvantages in Victoria, Australia

The study examined the relationship between dispensing patterns of prescription opioids, neighborhood-disadvantage-index, and standardized doses dispensed. Three-year’s dispensing data drawn from 80 local government areas (LGAs) within Victoria, Australia’s second most populous state, was analyzed. Quantities dispensed in defined daily dose (DDD)/1000-people/day were computed for LGAs of low, moderate, high, and very high socio-economic disadvantage. LGAs with various levels of dispensing, and neighborhood disadvantage were identified and mapped. A multivariable regression model examined the effect of neighborhood level disadvantage and identified other factors that are associated with standardized doses dispensed. More women were dispensed opioids than men. Dispensing increased with increasing age. Most of the LGAs with relatively high dispensing were socioeconomically disadvantaged and located outside the major cities. Dispensing gradually increased from low disadvantage to very high disadvantage areas. Dispensing of standardized doses were consistently higher in rural areas than in urban areas. Neighborhood level disadvantage, age, sex, and urbanization were significant factors in the standardized doses dispensed. As inappropriate dispensing of opioids is a major public health problem, research should facilitate understanding of utilization in small areas to enable tailored public health programs. Nationwide and consistent introduction of real-time prescription drug-monitoring programs, and structural interventions to reduce the fundamental causes of socioeconomic disadvantage and isolation are recommended.