Australian Pharmaceutical Benefits Scheme Research Articles

Cross-Sectional and Longitudinal Associations Between Treatment for Herpes Virus Infection and the Dispensing of Antidementia Medicines: An Analysis of the Australian Pharmaceutical Benefits Scheme Database.

Evidence from previous observational studies suggest that infection by herpes simplex virus (HSV) and varicella zoster virus (VZV) increase the risk of dementia. To investigate if older adults exposed to HSV treatment have lower risk of dementia than the rest of the population. We used the 10% Australian Pharmaceutical Benefits Scheme (PBS) database from 2013 to 2022 to ascertain the cross-sectional, time-series and longitudinal association between exposure to HSV treatment and the dispensing of antidementia medicines. Participants were men and women aged 60 years or older. We used Anatomical Therapeutic Chemical (ATC) codes to identify medicines dispensed for the treatment of HSV and dementia. During the year 2022 6,868 (1.2%) of 559,561 of participants aged 60 years or over were dispensed antidementia agent. The odds ratio (OR) of being dispensed an antidementia agent among individuals dispensed treatment for HSV was 0.73 (99% CI = 0.56-0.95). Multilevel logistic regression for the 2013-2022 period for those dispensed HSV treatment was 0.87 (99% CI = 0.75-1.00). Split-time span series from 2013 was associated with hazard ratio of 0.98 (99% CI = 0.89-1.07) for individuals dispensed relative to those not dispensed HSV treatment. All analyses were adjusted for age, sex, and the dispensing of medicines for the treatment of diabetes, hyperlipidemia, hypertension, and ischemic heart disease. The dispensing of antiviral medicines for the treatment of HSV and VZV is consistently, but not conclusively, associated with decreased dispensing of antidementia medicines. This suggests that treatment of HSV and VZV infections may contribute to reduce the risk of dementia.

Real-world treatment patterns and outcomes for patients with CLL using the Australian pharmaceutical benefits scheme (PBS) dataset

This real-world retrospective cohort study using Australian Pharmaceutical Benefits Scheme (PBS) 10% investigated changes in chronic lymphocytic leukemia (CLL) treatment by line of therapy, time-to-next-treatment, treatment duration, and overall survival (OS). Overall, 803 patients received their first PBS-reimbursed CLL medication between 1 January 2011 to 31 July 2021 (median age: 70 years; 64.6% male), 289 post-1 August 2020. In 2011, most first-line (1 L) prescribing was fludarabine, cyclophosphamide, and rituximab (FCR). By 2021, common 1L were chlorambucil ± CD20 (26.1%), Bruton Tyrosine Kinase inhibitor (BTKi) (26.1%), and CD20 monotherapy (23.9%). In 2011, relapsed/refractory (R/R) CLL treatment was CD20 monotherapy or FCR. By 2021, BTKi (57.7%) and venetoclax ± CD20 (26.1%) were most common. Compared to FCR, 1 L treatment duration (Hazard Ratio) was shorter for CD20 monotherapy (1.7) or chlorambucil ± CD20 (2.5). In R/R CLL, median duration was 24 (ibrutinib) and 19 months (venetoclax). Median OS was 127 months. CLLtreatment pattern shave greatly changed in Australia since the introduction of novel therapies.

Excess Risk of Injury in Individuals With Type 1 or Type 2 Diabetes Compared With the General Population.

To estimate the relative risk (RR) and excess hospitalization rate for injury in individuals with diabetes compared with the general population. Data were obtained from the Australian National Diabetes Services Scheme, hospitalization data sets, the Australian Pharmaceutical Benefits Scheme, the National Death Index, and the census spanning from 2011 to 2017. Hospitalizations for injury were coded as head and neck, lower-extremity, upper-extremity, or abdominal and thoracic injury; burns; or other injury. Poisson regression was used to estimate the age- and sex-adjusted RR of hospitalization for injury. The total number of hospitalizations for any injury was 117,705 in people with diabetes and 3,463,173 in the general population. Compared with that in the general population, an elevated adjusted risk of admission was observed for any injury (RR 1.22; 95% CI 1.21, 1.22), head and neck (1.28; 1.26, 1.30), lower extremity (1.24; 1.23, 1.26), abdominal and thoracic (1.29; 1.27, 1.30), upper extremity (1.03; 1.02, 1.05), burns (1.52; 1.44, 1.61), and other injury (1.37; 1.33, 1.40). The adjusted RR of any injury was 1.62 (1.58, 1.66) in individuals with type 1 diabetes, 1.65 (1.63, 1.66) in those with type 2 diabetes who were taking insulin, and 1.07 (1.06, 1.08) in individuals with type 2 diabetes not using insulin. Falls were the primary cause of injury in individuals with diabetes. Individuals with diabetes, especially those using insulin, had a higher risk of hospitalization for injury compared with the general population.

Cross-sectional, case-control and longitudinal associations between exposure to glucagon-like peptide-1 receptor agonists and the dispensing of antidepressants.

To determine if the dispensing of glucagon-like peptide (GLP)-1 receptor agonists is associated with increased dispensing of antidepressants. We used cross-sectional, case-control and retrospective cohort study designs to examine the association between dispensed GLP-1 receptor agonists and antidepressants between 2012 and 2022 in the 10% random sample of the Australian Pharmaceutical Benefits Scheme (PBS) data. PBS-listed GLP-1 receptor agonists, exenatide, dulaglutide and semaglutide were the exposures. Outcomes were the odds ratio [ORs; 99% confidence interval (CI)] and hazard ratio (99% CI) of being dispensed any antidepressant. Analyses were adjusted for demographic measures and the dispensing of medicines to manage cardiovascular diseases or anxiety/insomnia. Statistical tests were two-sided at the 1% level of significance. In total, 358 075 of 1 746 391 individuals were dispensed antidepressants, and 8495 of the 24 783 dispensed a GLP-1 receptor agonist were also dispensed an antidepressant in 2022 (OR 1.44; 99% CI 1.38-1.50); 24 103 of the 1 746 391 participants had been dispensed a GLP-1 receptor agonist between 2012 and 2021, and of these 8083 were dispensed antidepressants in 2022 (OR 1.52; 99% CI 1.46-1.59). The 2012 cohort included 1 213 316 individuals who had not been dispensed antidepressants that year. The hazard ratio of being dispensed an antidepressant between 2013 and 2022 following the dispensing of a GLP-1 receptor agonist was 1.19 (99% CI 1.12-1.27). Additional analyses restricting the time of exposure confirmed these associations for all PBS-listed GLP-1 receptor agonists. Individuals exposed to GLP-1 receptor agonists are at greater risk of being dispensed antidepressants. The possible impact of GLP-1 receptor agonists on the mood of consumers requires ongoing vigilance and further research.

Biological Agents in the Treatment of Crohn's Disease: A Propensity Score-Matched Analysis From the Prospective Persistence Australian National IBD Cohort (PANIC3) Study.

Comparative effectiveness research provides data on the relative benefits and risks between treatments. In Crohn's disease (CD), however, there are few head-to-head studies comparing advanced therapies and none with long-term follow-up. Real-world effectiveness, defined by treatment persistence, obtained from prospective population-based patient cohorts, may help determine the best sequencing and positioning of biological agents. We analyzed the prospectively collected population-based Australian national Pharmaceutical Benefits Scheme dispensing data registry (2005-2019) for CD. There is no mandated biological agent prescribing order, and all citizens and permanent residents are eligible for treatment irrespective of insurance status. Propensity score matching was performed to reduce selection bias. There were 2,029 lines of therapy in 1,446 patients (median age 43 years, interquartile range 34-58, 44% male patients) over the 15-year period with 5,618 patient-years of follow-up. Per line of therapy, 915/2,029 (45.1%) patients used adalimumab, 722/2,029 (35.6%) used infliximab, 155/2,029 (7.6%) used vedolizumab, and 237/2,029 (11.7%) used ustekinumab. When used in biological agent-naive patients, there was no difference in persistence between any agent ( P > 0.05). Used after first line in biological agent-experienced CD, ustekinumab had significantly better persistence than non-ustekinumab biological agents ( P = 0.0018), vs anti-tumor necrosis factor (TNF) alpha therapy ( P = 0.006) or vedolizumab ( P < 0.001). Ustekinumab persistence was unaffected by prior biological agent exposure ( P = 0.51). After anti-TNF use, ustekinumab had superior persistence to an alternative anti-TNF agent ( P = 0.033) and to vedolizumab ( P = 0.026). Using a propensity score-matched analysis adjusted for age, immunomodulator use, and bio-exposed status, ustekinumab had superior persistence to anti-TNF ( P = 0.01). Multivariate predictors of worse persistence were the use of a non-ustekinumab biological agent (adjusted hazard ratio 2.10, P < 0.001), and bio-experienced status (adjusted hazard ratio 1.23, P < 0.001). This large national prospective database with nonhierarchical prescribing of biological agents did not identify superior persistence of any agent in bio-naive CD. However, for patients with bio-experienced CD, persistence was greater with ustekinumab.

Observational evidence linking psychotropic medicines to the dispensing of opioid agents in later life.

The use of opioid medicines is common in developed countries, particularly among older adults and those with mental health disorders. It is unclear if the association between mental disorders and opioid medicines is causal, or is due to reverse causality or confounding. We used a 10% random sample of the Australian Pharmaceutical Benefits Scheme (years 2012-2022) to examine the cross-sectional, case-control and longitudinal association between the dispensing of antidepressants, anxiolytics, hypnotics, antipsychotics and lithium, and opioid medicines. We used logistic regression, structural equation models (SEM), and Cox regression to analyze the data. Analyses were adjusted for age (years), sex, and number of non-psychotropic medicines dispensed during the year. The 2022 file contained 804 334 individuals aged 50 years or over (53.1% women), of whom 181 690 (22.6%) received an opioid medicine. The adjusted odds ratio of being dispensed opioid medicines was 1.44 (99% CI = 1.42-1.46) for antidepressants, 1.97 (99% CI = 1.92-2.03) for anxiolytics, 1.55 (99% CI = 1.51-1.60) for hypnotics, 1.32 (99% CI = 1.27-1.38) for antipsychotics, and 0.60 (99% CI = 0.53-0.69) for lithium. Similar associations were noticed when we compared participants who were or not dispensed opioid medicines in 2022 for exposure to psychotropic agents between 2012 and 2021. SEM confirmed that this association was not due to reverse causality. The dispensing of antidepressants was associated with increased adjusted hazard (HR) of subsequent dispensing of opioid medicines (HR = 1.29, 99% CI = 1.27-1.30). Similar associations were observed for anxiolytics, hypnotics and antipsychotics, but not lithium. The dispensing of opioid medicines is higher among older individuals exposed to antidepressants, anxiolytics, hypnotics and antipsychotics than those who are not. These associations are not due to reverse causality or study design. Preventive strategies seeking to minimise the risk of inappropriate use of opioid medicines in later life should consider targeting this high-risk population.

Medicine utilization studies in Australian individual-level dispensing data: A blinded, multi-center replicated analysis.

Medicine dispensing data require extensive preparation when used for research and decisions during this process may lead to results that do not replicate between independent studies. We conducted an experiment to examine the impact of these decisions on results of a study measuring discontinuation, intensification, and switching in a cohort of patients initiating metformin. Four Australian sites independently developed a HARmonized Protocol template to Enhance Reproducibility (HARPER) protocol and executed their analyses using the Australian Pharmaceutical Benefits Scheme 10% sample dataset. Each site calculated cohort size and demographics and measured treatment events including discontinuation, switch to another diabetes medicine, and intensification (addition of another diabetes medicine). Time to event and hazard ratios for associations between cohort characteristics and each event were also calculated. Concordance was assessed by measuring deviations from the calculated median of each value across the sites. Good agreement was found across sites for the number of initiators (median: 53 127, range: 51 848-55 273), gender (56.9% female, range: 56.8%-57.1%) and age group. Each site employed different methods for estimating days supply and used different operational definitions for the treatment events. Consequently, poor agreement was found for incidence of discontinuation (median 55%, range: 34%-67%), switching (median 3.5%, range: 1%-7%), intensification (median 8%, range: 5%-12%), time to event estimates and hazard ratios. Differences in analytical decisions when deriving exposure from dispensing data affect replicability. Detailed analytical protocols, such as HARPER, are critical for transparency of operational definitions and interpretations of key study parameters.

Use of Analgesic and Anti-Inflammatory Medicines before and after Initiation of Biological Disease-Modifying Antirheumatic Drugs for Rheumatoid Arthritis

Background. Rheumatoid arthritis (RA) is an inflammatory condition that causes joint damage and is associated with pain. The biological disease-modifying antirheumatic drugs (bDMARDs) for RA are linked to additional therapeutic benefits as they suppress the inflammatory process, which in turn prevents joint erosion and reduces pain. Thus, the use of bDMARDs has the potential to reduce the need for other analgesic and anti-inflammatory therapies for RA. The aim of this study was to examine the analgesic and anti-inflammatory use around the initiation of bDMARDs. Methods. A cohort study was conducted using a 10% random sample of the population dispensing medicines under the Australian Pharmaceutical Benefits Scheme. People who initiated the first bDMARD for RA between 2014 and 2018 were included. The proportion who received any analgesic or anti-inflammatory, including nonsteroidal anti-inflammatory drugs, opioids, or glucocorticoids, in the twelve months prior to and post-bDMARD initiation was determined and compared using regression models. Results. There were 18,360 persons in the cohort, with a mean age of 55 years, and 69% were women. The use of any analgesic or anti-inflammatory in both tumor necrosis factor inhibitor (TNFi) and non-TNF initiators increased prior to initiation of bDMARD–from 43% to 52% in TNFi and from 52% to 63% in non-TNF initiators. In both groups, overall use decreased significantly post initiation to 37% and 42% in TNFi and non-TNF initiators, respectively (p&lt;0.0001). bDMARD initiation was associated with lower use of glucocorticoid therapy, but there was no decreasing effect on opioid use. Conclusion. While the use of any analgesic or anti-inflammatories decreased post-initiation of bDMARDs for RA, more than one-third of people were dispensed analgesic or anti-inflammatory agents twelve months post initiation. Ongoing review of the need for analgesic and glucocorticoids appears warranted, with assessment of nonpharmacological approaches to support pain management.

OP27 Impact Of Generic Entry Of Pharmaceuticals On Drug Prices In Australia

IntroductionPolicy makers are keen to introduce cost containment measures in medicine spending due to aging populations and fiscal pressure. A major price reform was applied to the Australian Pharmaceutical Benefits Scheme (PBS) in 2014. This aimed to stimulate price reductions by increasing competition among generics, amidst growing evidence at the time of unnecessarily high generic medicine prices in Australia. The aim of this study was to estimate the effect of patent expiration and generic competition on drug prices, while controlling for other determinants of drug prices in Australia.MethodsA dataset from publicly available sources was constructed using monthly data on the price of drugs listed on the PBS from October 2014 to July 2022. The information included the generic drug name, item code, date, approved ex-manufacturer price, dispensed price per maximum quantity, and brand names. This was supplemented with monthly government spending and number of prescriptions filled per item code. A fixed effects regression model was used to estimate the effect of patent expiration and generic competition on dispensed drug prices.ResultsThe model estimated that introducing generics in Australia led to an 18 percent decrease in prices, excluding further decreases resulting from other controlled variables. The price elasticity of total prescriptions filled was estimated to be -0.6, suggesting that a one percent increase in prescriptions filled resulted in drug prices being lowered by 0.6 percent. This reflects the fact that, on average, firms reacted by reducing prices to increase market share when faced with an increase in quantity demanded. Each extra competitor was estimated to result in a reduction in prices of roughly 1.8 percent.ConclusionsThese results show that entry of generics into the Australian pharmaceutical market resulted in a significant reduction in drug prices. However, this alone does not provide empirical support for the effectiveness of these price reforms in generating savings by inducing generic competition, especially over other forms of pharmaceutical regulation.

Chronic Obstructive Pulmonary Disease Adverse Event Signals Associated with Potential Inhibitors of Glutathione Peroxidase 1: A Sequence Symmetry Analysis.

Prior molecular modelling analysis identified several medicines as potential inhibitors of glutathione peroxidase 1 (GPx1) which may contribute to development or progression of chronic obstructive pulmonary disease (COPD). This study investigates 40 medicines (index medicines) for signals of COPD development or progression in a real-world dataset. Sequence symmetry analysis (SSA) was conducted using a 10% extract of Australian Pharmaceutical Benefits Scheme (PBS) claims data between January 2013 and September 2019. Patients must have been initiated on an index medicine and a medicine for COPD development or progression within 12 months of each other. Sequence ratios were calculated as the number of patients who initiated an index medicine followed by a medicine for COPD development or progression divided by the number who initiated the index medicine second. An adjusted sequence ratio (aSR) was calculated which accounted for changes in prescribing trends. Adverse drug event signals (ADEs) were identified where the aSR lower 95% confidence interval (CI) was greater than 1. Twenty-one of 40 (53%) index medicines had at least one ADE signal of COPD development or progression. Signals of COPD development, as identified using initiation of tiotropium, were observed for atenolol (aSR 1.32, 95% CI 1.23-1.42) and naproxen (aSR 1.14, 95% CI 1.06-1.23). Several signals of COPD progression were observed, including initiation of fluticasone propionate/salmeterol following initiation of atenolol (aSR 1.44, 95% CI 1.30-1.60) and initiation of aclidinium/formoterol following initiation of naproxen (aSR 2.21, 95% CI 1.34-3.65). ADE signals were generated for several potential GPx1 inhibitors; however, further validation of signals is required in large well-controlled observational studies.

Medication use in people with cystic fibrosis before and after modulator therapy

BackgroundLong-term changes in medication dispensings post cystic fibrosis transmembrane conductance regulator (CFTR) modulator initiation have not been described. Our study aimed to investigate changes in medication use following the initiation of modulator therapy in people with cystic fibrosis (PwCF) in Australia. MethodsUsing a 10% sample of the Australian Pharmaceutical Benefits Scheme (PBS) data between 2013 and 2022, linear regression was used to analyse dispensings in PwCF who initiated any modulator (cases) and matched PwCF controls not dispensed a modulator. The difference in mean number of total monthly dispensings pre- and post-modulator initiation was analysed, with separate analyses by medication class. ResultsA total of 247 cases were matched 1:1 to controls (case and control median age 21 years (IQR: 13–32), 55.1% male). Immediately after modulator initiation, the mean number of dispensings was 0.9 higher in the modulator group, but then decreased to the level of controls after approximately 5 years. After 7.5 years, cases had decreased opioids compared to the pre-modulator period (β-coefficient: −0.00131, 95% CI: −0.00164, −0.00097) whilst controls did not (β: −0.00014, 95% CI: −0.00042, 0.00014). Over the same time period controls had an increase in psychotropics (β: 0.00389, 95% CI:0.00295, 0.00484) whilst cases remained stable (β: −0.00014, 95% CI: −0.0006, 0.00031). Women's health medications increased in cases (β:0.00026, 95% CI:0.0001, 0.00042) but decreased in controls (β: 0.00044, 95% CI: 0.00063, −0.00025). ConclusionsModulator initiation in PwCF was associated with decreased dispensings of opioids and psychotropics, and increased dispensings of women's health medications, suggesting improved patient outcomes across multiple clinical domains.

The Effect of Vitamin D Supplementation on Hypothyroidism in the Randomized Controlled D-Health Trial.

Background: Hypothyroidism is common, and in iodine-sufficient areas, it is primarily caused by autoimmune destruction of the thyroid gland. Observational studies have consistently shown an inverse association between serum 25-hydroxyvitamin D concentration and autoimmune diseases; however, there is a lack of evidence from randomized controlled trials to support a benefit of vitamin D supplementation, particularly for autoimmune thyroid diseases. We, therefore, aimed to assess the effect of vitamin D supplementation on the incidence of hypothyroidism. Methods: We analyzed data from the D-Health Trial (n = 21,315), a randomized double-blind placebo-controlled trial of 60,000 international units per month of supplemental vitamin D3 among Australians aged 60 years and over. Hypothyroidism, a tertiary outcome of the D-Health Trial, was defined by treatment with levothyroxine, ascertained through linkage with the Australian Pharmaceutical Benefits Scheme. The outcome was time to first prescription of levothyroxine. We began follow-up at 12 months after randomization; people who had died or who had been dispensed levothyroxine during the first year were excluded. Flexible parametric survival models were used to assess the effect of vitamin D supplementation on hypothyroidism, overall and within strata defined by age, sex, body mass index, and predicted baseline vitamin D status. Results: We included 17,851 participants in the main analysis (vitamin D = 8939; placebo = 8912). During a median follow-up of 4.1 years (interquartile range 4.1-4.1), 293 participants developed hypothyroidism (vitamin D = 138 [1.5%]; placebo = 155 [1.7%]). Vitamin D supplementation did not significantly reduce the incidence of hypothyroidism (overall hazard ratio [HR] 0.89; 95% confidence interval [CI] 0.71-1.12). There was some suggestion of an effect in females (overall HR 0.78; CI 0.58-1.06) but not in males (overall HR 1.06; CI 0.74-1.50; p interaction 0.20). Conclusions: Vitamin D supplementation did not reduce the incidence of hypothyroidism overall; however, the possible beneficial effect observed in females warrants further investigation. Clinical Trial Registration: Australian New Zealand Clinical Trials Registry: ACTRN12613000743763.

Progressing Towards Same-Day Discharges After Robotic-Assisted Radical Prostatectomy; Safe and Cost Effective to Discharge Without Routine Blood Tests.

Changing population demographics and the recent SARS-CoV-2 pandemic have forever changed healthcare, with increasing demands on straining systems. The economic cost is yet to be fully realised, with growing concerns around the current system's ability to accommodate the ageing comorbid population. Consequently, a paradigm shift has taken place in healthcare systems, prioritizing cost accountability. In the absence of established guidelines or robust literature, the use of laboratory tests postoperatively is often guided solely by clinician preference. This study presents a retrospective analysis that investigates the utility and cost implications of routine postoperative investigation following robotic-assisted radical prostatectomies. The findings aim to emphasise the importance of evidence-based practices and cost-effective approaches in postoperative care. A retrospective analysis was performed on all robotic-assisted radical prostatectomies (RARP) identified from a single institution between 29th June 2017 to 28th June 2019. This interval was chosen in an attempt to avoid bias or confounding variables associated with the SRS-CoV-2 pandemic. A single clinician conducted a comprehensive medical record review using unit record numbers corresponding to identified procedural codes. Demographics and variables were recorded, including postoperative test results, hospital length of stay and 30-day readmission rates. Patients were assigned to either 'Routine Postoperative tests' (RPOT) or 'No Routine Postoperative tests' (No RPOT) and a comparative analysis was performed. Using the Australian National Pharmaceutical Benefits Scheme (PBS) pricing guide, total expenditure was calculated. A total of 319 patients were included in the study with an average of 2.5 tests per patient within the first 24 hours. Routine postoperative tests had no bearing on outcomes, with comparable readmission rates between cohorts, and a significantly shorter length of stay in the "No routine postoperative tests" group when compared to the "Routine Postoperative Tests". A total of 1028 tests were performed within the first 48 hours following surgery with expenditure on routine testing totalling $20,516 based on the Australian PBS pricing schedule. Abnormal results were returned on 96% of patients. In the RPOT group, 18 out of the 20 common interventions occurred from 302 RARP. Among the patients in the RPOT group, eight individuals underwent blood transfusions. However, none of these patients met the hospital-specific criteria for transfusion, which require a hemoglobin level below 70 or symptomatic presentation with a hemoglobin level below 80. The data suggests routine postoperative laboratory has no bearing on re-admission rates, with patients experiencing significantly shorter hospital stays. Furthermore, our results indicate inefficient use of routine postoperative laboratory, with few clinical interventions, frequent abnormal results, and significant accumulative expenses.

Study profile: the Genetics of Glaucoma Study

PurposeGlaucoma, a major cause of irreversible blindness, is a highly heritable human disease. Currently, the majority of the risk genes for glaucoma are unknown. We established the Genetics of Glaucoma...

Patterns of suboptimal antipsychotic use and misuse in Australia: What can routinely collected data tell us?

There are increasing concerns about harms related to suboptimal antipsychotic use. Here we describe recent population-based trends in antipsychotic use and harms in Australia and identify population groups exhibiting patterns of use likely to contribute to these harms. Using population-based data from the Australian Pharmaceutical Benefits Scheme (2015-2020), poisoning calls to the New South Wales (NSW) Poisons Information Centre (2015-2020) and poisoning deaths in all coronial records (2005-2018) in Australia, we measured trends in the prevalence of antipsychotic use and related deaths and poisonings. We applied latent class analyses to identify patterns of antipsychotic use that may contribute to harms. Quetiapine and olanzapine had the highest prevalence of use between 2015 and 2020. Noteworthy trends included increases of 9.1% and 30.8% in quetiapine use and poisonings, while olanzapine use decreased by 4.5% but poisonings increased by 32.7%. Quetiapine and olanzapine poisonings and related deaths had the highest rates of co-ingestion of opioids, benzodiazepines and pregabalin compared to other antipsychotics. We identified six distinct population groups using antipsychotics: (i) ongoing high-dose use with sedatives (8%), (ii) ongoing use (42%), (iii) ongoing use with analgesics and sedatives (11%), (iv) long-term low-dose use (9%), (v) sporadic use (20%) and (vi) sporadic use with analgesics (10%). Ongoing potentially suboptimal antipsychotic use and associated harms highlight the need to monitor such patterns of use, for example through prescription monitoring systems.

Long-acting reversible contraception prescribing coverage by nurse practitioners and midwives in Australia

BackgroundExpanded patient access to long-acting reversible contraception (LARC) is needed to support patient choice and access to efficacious forms of contraception. Little is known about nurse practitioner (NP) and midwife LARC prescribing. AimsTo examine LARC prescribing by NPs and midwives in Australia. MethodsA cross-sectional study of Australian Pharmaceutical Benefits Scheme dispensing data from 2018 to 2021 for females aged 15–54. Age‐standardised rates were calculated by state, remoteness area, and level 3 statistical areas (SA3s). FindingsDespite a 1.6 fold increase since 2018, NPs and midwives accounted for 0.82 % (n = 2184) of prescriptions for LARC dispensed in 2021. The percentage of services in 2021 was greater in outer regional (2.21 %) and lowest in major cities (0.68 %) and was higher for the implant (0.92 %) compared with the hormonal intrauterine device (0.76 %). The proportion of total SA3s where a NP/midwife prescribed LARC increased from 23.35 % in 2018 to 29.94 % in 2021. NP/midwife LARC prescribing was highest in outer regional (42.6 %) and lowest in remote areas (18.8 %). When stratified by state/territory, coverage of SA3s was highest in Australian Capital Territory (50.0 %) and lowest in the Northern Territory (11.1 %). Discussion and conclusionOur findings suggest that whilst there has been an increase in NP and midwife LARC prescribing, the overall rate remains low and coverage across Australia appears fragmented. NPs and midwives are well placed to enhance women’s access to efficacious forms of contraception, but this requires future efforts to identify and address critical barriers (e.g. legislative, funding, training) to service provision.

Cohort profile: POPPY II – a population-based cohort examining the patterns and outcomes of prescription opioid use in New South Wales, Australia

PurposeThe POPPY II cohort is an Australian state-based cohort linking data for a population of individuals prescribed opioid medicines, constructed to allow a robust examination of the long-term patterns and...

Have changing practices in salvage medical options affected colectomy rates in acute severe ulcerative colitis?

In 2014, infliximab (IFX) was listed on the Australian Pharmaceutical Benefits Scheme for acute severe ulcerative colitis (ASUC) and is now the preferred option for medical salvage, superseding cyclosporin A (CsA). Optimal dosing schedules for IFX remain unknown. The authors aim to evaluate the effect of changing from predominantly CsA to almost exclusively IFX for the treatment of steroid-refractory ASUC on colectomy rates. A retrospective review was performed of patients admitted with ASUC between 2012 and 2020. Patients were categorised into two groups according to year of presentation - either 'historical treatment' cohort (2012-2014), when CsA was primarily used, or 'contemporary treatment' cohort (2014-2020), when IFX was mostly prescribed, in either standard or intensive doses. One hundred thirty-nine patients were included; 37 in the historical treatment cohort and 102 in the contemporary treatment cohort. In the historical treatment cohort, 12 of 37 received salvage therapy and eight (67%) received CsA. In the contemporary treatment cohort, 49 of 102 patients received salvage therapy, 40 (82%) with IFX, of whom 22 (53%) received intensified doses. Colectomy rates were similar at 30 days, 6 months and 12 months between historical and contemporary treatment cohorts (14% vs 12% [P = 0.77], 19% vs 18% [P > 0.99],and 22% vs 18% [P = 0.63], respectively). Difference in 12-month colectomy rates between standard versus intensive IFX did not meet statistical significance (three of 21 [14%] vs nine of 22 [41%]. respectively; P = 0.09). There was no difference in 30-day, 6-month or 12-month colectomy rates between the historical treatment and contemporary treatment cohorts. The use of IFX, rather than CsA, even at intensified dosing, does not appear to reduce the colectomy rate observed in our patients.

Lithium Dispensed for Adults Aged ≥ 50 Years Between 2012 and 2021: Analyses of a 10% Sample of the Australian Pharmaceutical Benefits Scheme

BackgroundLithium use seems to be declining in clinical practice. We examined the proportion of adults aged ≥ 50 years dispensed lithium between 2012 and 2021, and investigated the proportion of lithium users dispensed other medications. MethodsWe used a 10% random sample data of the Australian Pharmaceutical Benefits Scheme from 2012 to 2021, and limited our analyses to adults aged ≥ 50 years. We retrieved data on lithium, other mood stabilisers, antipsychotics, antidepressants, anxiolytics and hypnotics, and medications for the treatment of other health systems. ResultsWe received 7081939 person-years records (53.2% women). The proportion of participants dispensed lithium decreased with age: 0.4% for those aged 50-59 years to < 0.1% for people aged ≥ 90 years. The dispensing of lithium increased over 10 years for those aged 50-69 and decreased in those older than 80 years. Among people dispensed lithium, nearly 1 in 5 were dispensed another mood stabiliser. Antipsychotics and antidepressants were dispensed to about 60% of participants dispensed lithium, with antidepressants dispensed more frequently to women than men. About 20% of people dispensed lithium were dispensed anxiolytics/hypnotics, more frequently for women than men. Medications to treat diseases of the alimentary, cardiovascular, endocrine and nervous systems were commonly dispensed to those dispensed lithium, as were antibiotics. ConclusionsWhile the dispensing of lithium increased among young older adults since 2015 when guidelines for the management of mood disorders were published, our findings suggest that lithium may be under-utilised for the management of bipolar disorder in later life.

PATTERNS AND PREDICTORS OF OUTPATIENT ANTIBIOTIC DISPENSATION FOLLOWING TOTAL HIP AND KNEE ARTHROPLASTY

This study aimed to evaluate the month-to-month prevalence of antibiotic dispensation in the 12 months before and after total knee arthroplasty (TKA) and total hip arthroplasty (THA) and to identify factors associated with antibiotic dispensation in the month immediately following the surgical procedure.In total, 4,115 THAs and TKAs performed between April 2013 and June 2019 from a state-wide arthroplasty referral centre were analysed. A cross-sectional study used data from an institutional arthroplasty registry, which was linked probabilistically to administrative dispensing data from the Australian Pharmaceutical Benefits Scheme. Multivariable logistic regression was carried out to identify patient and surgical risk factors for oral antibiotic dispensation.Oral antibiotics were dispensed in 18.3% of patients following primary TKA and 12.0% of patients following THA in the 30 days following discharge. During the year after discharge, 66.7% of TKA patients and 58.2% of THA patients were dispensed an antibiotic at some point. Patients with poor preoperative health status were more likely to have antibiotics dispensed in the month following THA or TKA. Older age, undergoing TKA rather than THA, obesity, inflammatory arthritis, and experiencing an in-hospital wound-related or other infectious complications were associated with increased antibiotic dispensation in the 30 days following discharge.A high rate of antibiotic dispensation in the 30 days following THA and TKA has been observed. Although resource constraints may limit routine wound review for all patients by a surgeon, a select cohort may benefit from timely specialist review postoperatively. Several risk factors identified in this study may aid in identifying appropriate candidates for such changes to follow-up care.