Factors associated with cardiac implantable electronic device-related infections, New South Wales, 2016-21: a retrospective cohort study.

OBJECTIVES: To quantify the rate of cardiac implantable electronic device (CIED)-related infections and to identify risk factors for such infections. DESIGN: Retrospective cohort study; analysis of linked hospital admissions and mortality data. SETTING, PARTICIPANTS: All adults who underwent CIED procedures in New South Wales between 1 January 2016 and 30 June 2021 (public hospitals) or 30 June 2020 (private hospitals). MAIN OUTCOME MEASURES: Proportions of patients hospitalised with CIED-related infections (identified by hospital record diagnosis codes); risk of CIED-related infection by patient, device, and procedural factors. RESULTS: Of 37 675 CIED procedures (23 194 men, 63.5%), 500 were followed by CIED-related infections (median follow-up, 24.9 months; interquartile range, 11.2-40.8 months), including 397 people (1.1%) within twelve months of their procedures, and 186 of 10 540 people (2.5%) at high risk of such infections (replacement or upgrade procedures; new cardiac resynchronisation therapy with defibrillator, CRT-D). The overall infection rate was 0.50 (95% confidence interval [CI], 0.45-0.54) per 1000 person-months; it was highest during the first month after the procedure (5.60 [95% CI, 4.89-6.42] per 1000 person-months). The risk of CIED-related infection was greater for people under 65 years of age than for those aged 65-74 years (adjusted hazard ratio [aHR], 1.71; 95% CI, 1.32-2.23), for people with CRT-D devices than for those with permanent pacemakers (aHR, 1.46; 95% CI, 1.02-2.08), for people who had previously undergone CIED procedures (two or more v none: aHR, 1.51; 95% CI, 1.02-2.25) or had CIED-related infections (aHR, 11.4; 95% CI, 8.34-15.7), or had undergone concomitant cardiac surgery (aHR, 1.62; 95% CI, 1.10-2.39), and for people with atrial fibrillation (aHR, 1.33; 95% CI, 1.11-1.60), chronic kidney disease (aHR, 1.54; 95% CI, 1.27-1.87), chronic obstructive pulmonary disease (aHR, 1.37; 95% CI, 1.10-1.69), or cardiomyopathy (aHR 1.60; 95% CI, 1.25-2.05). CONCLUSIONS: Knowledge of risk factors for CIED-related infections can help clinicians discuss them with their patients, identify people at particular risk, and inform decisions about device type, upgrades and replacements, and prophylactic interventions.

Real-world evidence on the association between cardiac implantable electronic device infection and all-cause mortality.

AIMS: An infection following cardiac implantable electronic device (CIED) procedure is a serious complication, but its association with all-cause mortality is inconsistent across observational studies. To quantify the association between CIED infection and all-cause mortality in a large, contemporary cohort from New South Wales, Australia. METHODS AND RESULTS: This retrospective cohort study used linked hospital and mortality data and included all patients aged >18 years who underwent a CIED procedure between July 2017 and September 2022. Cardiac implantable electronic device infection was defined by the presence of relevant diagnosis codes. Cox regression to estimate adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) for the association of CIED infection with mortality, at 1-year, and at the end of follow-up, with CIED infection included as a time-dependent variable, and other potential risk factors for mortality included as fixed covariates. We followed 37,750 patients with CIED procedures {36% female, mean age [standard deviation (SD)] 75.8 [12.7] years}, and 487 (1.3%) CIED infections were identified. We observed 5771 (15.3%) deaths during an average follow-up of 25.2 (SD 16.8) months. Compared with no infection group, patients with CIED infection had a higher Kaplan-Meier mortality rate (19.4 vs. 6.8%) and adjusted hazard of mortality (aHR 2.73, 95% CI 2.10-3.54) at 12 months post-procedure. These differences were attenuated but still remained significant at the end of follow-up (aHR 1.83, 95% CI 1.52-2.19). CONCLUSION: In a complete, state-wide cohort of CIED patients, infection was associated with higher risks of both short-term and long-term mortality.

Comparison of long-term outcomes of bioprosthetic and mechanical aortic valve replacement in patients younger than 65 years.

OBJECTIVES: The objectives of this study were to compare rates of mortality and reoperations for patients aged younger than 65 years who underwent surgical aortic valve replacement (AVR). AVR with a bioprosthetic valve (BV) is increasing among younger patients, however evidence to inform the choice between BV or mechanical valve is limited. METHODS: We performed a retrospective cohort study using linked hospital and mortality data from Australia, for 3969 AVR patients between 2003 and 2018. We compared outcomes for valves in inverse probability of treatment-weighted cohorts, stratified according to age (18-54 years; 55-64 years). We used weighted Cox regression models to estimate hazard ratios (HRs) and weighted cumulative incidence function for subdistribution hazards, for follow-up intervals: 0 to 10 and >10 to 15 years. RESULTS: Among patients aged 55 to 64 years, there was no difference in mortality at 0 to 10 years. However, at >10 to 15 years, mortality was higher among BV recipients (HR, 1.56; 95% CI, 1.01-2.42). There was no difference among patients aged 18 to 54 years. Reoperation rates for patients aged 55 to 64 years did not differ according to valve type at 0 to 10 years, but were higher for BV than mechanical valve at >10 to 15 years (HR, 2.87; 95% CI, 1.69-4.86). For patients aged 18 to 54 years, reoperation rates were consistently higher for BV at both time intervals (HR, 2.54 [95% CI, 1.03-6.25] and HR, 4.48 [95% CI, 2.15-9.32], respectively). CONCLUSIONS: Patients aged 55 to 64 years who received a BV had a higher risk of mortality beyond 10 years. Rates of reoperations were higher among patients implanted with a BV in the entire cohort. Further investigation of long-term outcomes among patients with a BV is necessary. Continuous long-term monitoring of BV technologies will ensure evidence-based decision-making and regulation.

Long-Term Outcomes Following Elective Repair of Intact Abdominal Aortic Aneurysms: A Comparison Between Open Surgical and Endovascular Repair Using Linked Administrative and Clinical Registry Data.

OBJECTIVE: Compare long-term mortality, secondary intervention and secondary rupture following elective endovascular aneurysm repair (EVAR) and open surgical repair (OSR). BACKGROUND: EVAR has surpassed OSR as the most common procedure used to repair abdominal aortic aneurysm (AAA), but evidence regarding long-term outcomes is inconclusive. METHODS: We included patients in linked clinical registry and administrative data undergoing EVAR or OSR for intact AAA between January 2010 and June 2019. We used an inverse probability of treatment-weighted survival analysis to compare all-cause mortality, cause-specific mortality, secondary interventions and secondary rupture, and evaluate the impact of secondary interventions and secondary rupture on all-cause mortality. RESULTS: The study included 3460 EVAR and 427 OSR patients. Compared to OSR, the EVAR all-cause mortality rate was lower in the first 30 days [adjusted hazard ratio (HR) = 0.22, 95% confidence interval (CI) 0.140.33], but higher between 1 and 4 years (HR = 1.29, 95% CI 1.12-1.48) and after 4years (HR = 1.41, 95% CI 1.23-1.63). Secondary intervention rates were higher over the first 30 days (HR = 2.26, 95% CI 1.11-4.59), but lower between 1 and 4years (HR = 0.59, 95% CI 0.48-0.74). Secondary aortic intervention rates were higher across the entire follow-up period (HR = 2.52, 95% CI 2.06-3.07). Secondary rupture rates did not differ significantly (HR = 1.06, 95% CI 0.73-1.55). All-cause mortality beyond 1 year remained significantly higher for EVAR after adjusting for any secondary interventions, or secendary rupture. CONCLUSIONS: EVAR has an early survival benefit compared to OSR. However, elevated long-term mortality and higher rates of secondary aortic interventions and subsequent aneurysm repair suggest that EVAR may be a less durable method of aortic aneurysm exclusion.

Editor's Choice - Comparison of Outcomes for Major Contemporary Endograft Devices Used for Endovascular Repair of Intact Abdominal Aortic Aneurysms.

OBJECTIVE: To compare rates of mortality, rupture, and secondary intervention following endovascular repair (EVAR) of intact abdominal aortic aneurysms (AAA) using contemporary endograft devices from three major manufacturers. METHODS: This was a retrospective cohort study using linked clinical registry (Australasian Vascular Audit) and all payer administrative data. Patients undergoing EVAR for intact AAA between 2010 and 2019 in New South Wales, Australia were identified. Rates of all cause death, secondary rupture, and secondary intervention (subsequent aneurysm repair; other secondary aortic intervention) were compared for patients treated with Cook, Medtronic, and Gore standard devices. Inverse probability of treatment weighted proportional hazards and competing risk regression were used to adjust for patient, clinical, and aneurysm characteristics, using Cook as the referent device. RESULTS: This study identified 2 874 eligible EVAR patients, with a median follow up of 4.1 (maximum 9.5) years. Mortality rates were similar for patients receiving different devices (ranging between 7.0 and 7.3 per 100 person years). There was no statistically significant difference between devices in secondary rupture rates, which ranged between 0.4 and 0.5 per 100 person years. Patients receiving Medtronic and Gore devices tended to have higher crude rates of subsequent aneurysm repair (1.5 per 100 person years) than patients receiving Cook devices (0.8 per 100 person years). This finding remained in the adjusted analysis, but was only statistically significant for Medtronic devices (HR 1.57, 95% CI 1.02 - 2.47; HR 1.73, 95% CI 0.94 - 3.18, respectively). CONCLUSION: Major endograft devices have similar overall long term safety profiles. However, there may be differences in rates of secondary intervention for some devices. This may reflect endograft durability, or patient selection for different devices based on aneurysm anatomy. Continuous comparative assessments are needed to guide evidence for treatment decisions across the range of available devices.

Post-Discharge Antithrombotic Therapy Following Transcatheter Aortic Valve Implantation in Australian Patients.

BACKGROUND: Guidelines recommend antithrombotic therapy for patients following transcatheter aortic valve implantation (TAVI) to reduce the risk of ischaemic events and bioprosthetic valve thrombosis. OBJECTIVE: To describe antithrombotic dispensing within 30 days of discharge for Australian patients receiving TAVI. METHODS: We performed a state-wide retrospective cohort study using linked hospital and medicines dispensing data from January 2013 to December 2018 for all patients receiving TAVI in New South Wales, Australia. We identified patients dispensed oral anticoagulants (vitamin K antagonists [warfarin], direct oral anticoagulants [DOACs]) or clopidogrel within 30 days of discharge. We examined demographic and clinical predictors of antithrombotic dispensing. RESULTS: Our cohort comprised 1,217 patients who underwent TAVI; median age was 84 years and 707 (58.1%) were male. Of these, 808 patients (66.4%) had an antithrombotic dispensed within 30 days of hospital discharge. One-third (33.7%) of these patients were dispensed an anticoagulant (16.1% warfarin; 17.6% DOACs) and two-thirds (66.3%) were dispensed clopidogrel. Patients undergoing TAVI were more likely to be dispensed an antithrombotic medicine within 30-days of hospital discharge if they had been dispensed antithrombotic medicines (RR 1.07; 95% CI 1.03-1.11) or angiotensin-converting-enzyme inhibitors/angiotensin II receptor blockers (RR 1.04; 95% CI 1.00-1.07) in the 6 months prior to admission. Patients with a history of haemorrhage were less likely to be dispensed an antithrombotic medicine within 30 days of hospital discharge (RR 0.93; 95% CI 0.89-0.98). CONCLUSIONS: We observed gaps in best evidence pharmacotherapy for patients post-TAVI, with almost one third of patients not receiving antithrombotic medicines post-discharge. Further research is needed to quantify the impact of emerging clinical guidelines recommending single antiplatelet therapy, on adherence to best-practice care.

Age-stratified outcomes of bioprosthetic and mechanical aortic valve replacements in an Australian cohort of 13 377 patients.

OBJECTIVES: To quantify age-stratified outcomes of bioprosthetic valve (BV) and mechanical valve (MV) surgical aortic valve replacement (AVR) in Australian patients. DESIGN: Retrospective cohort study using population-based linked hospital morbidity and mortality data. SETTING: Public and private hospitals. PARTICIPANTS: Patients aged 18 years and over undergoing AVR from 2001 to 2013, stratified by age (18-64 years; 65+ years). MAIN OUTCOME MEASURES: Age-standardized index AVR rates; rates and multivariable-adjusted (age, sex, Charlson Comorbidity Index) incidence rate ratios (IRRs) for reoperation, incident cardiovascular events (hospitalization or death for acute myocardial infarction (AMI), stroke, major hemorrhage or thromboembolism) and mortality (cardiovascular and all-cause). RESULTS: Our cohort comprised 13 377 patients, of whom 3464 (26%) were aged 18-64 years. Annual age-standardized AVR rates increased by 2.7% with BV implants increasing in both age groups. After 5 years of follow-up, patients implanted with BV had lower rates of stroke (IRR: 0.40, 95% CI 0.27 to 0.60) and hemorrhage (IRR: 0.36, 95% CI 0.26 to 0.50). Among patients 65+ years, those implanted with BV had lower rates of AMI, hemorrhage, and cardiovascular and all-cause mortality than those implanted with MV (IRR: 0.71, 95% CI 0.53 to 0.96; IRR: 0.77, 95% CI 0.62 to 0.95; IRR: 0.80, 95% CI 0.69 to 0.92 and IRR: 0.85, 95% CI 0.74 to 0.97, respectively). After 6-10 years of follow-up, reoperation rates among patients 18-64 years were markedly higher in those implanted with BV compared with MV (IRR: 5.48, 95% CI 2.38 to 12.62) and rates of AMI were lower among patients implanted with BV compared with MV (IRR: 0.49, 95% CI 0.26 to 0.94). Among patients 65+ years rates of cardiovascular and all-cause mortality remained significantly lower for patients implanted with BV compared with MV. CONCLUSIONS: This study provides real-world evidence of AVR use and outcomes. Use of BV implants is increasing irrespective of age. Valve choice in younger patients requires thorough evaluation of patient factors influencing both short-term outcomes and longer-term risks of reoperation, stroke and hemorrhage.

Trends in methamphetamine and opioid use among clients of needle-syringe programs in Queensland, Australia: 2007-2015.

INTRODUCTION AND AIMS: Needle-syringe programs (NSP) are an underutilized source of data on drug injection trends; these data are essential for informing public health interventions. We examine trends in NSP service occasions from 2007-2015. DESIGN AND METHODS: Using standardised data from 26 NSP outlets through the Queensland NSP Minimum Data Set (QNSPMDS), trends in service occasions among clients intending to inject methamphetamine, heroin, opioid substitution therapy (OST) medications and other pharmaceutical opioids were assessed using multilevel mixed-effects negative binomial regression, adjusting for month, year, age and clustering by site. RESULTS: Over 1.5 million service occasions were recorded in 2007-2015. Methamphetamine was the main 'drug intended to inject' (33.7%), however cf. 2007, the incidence rate ratio decreased to 0.64 (95% CI: 0.62, 0.66) in 2009, remaining low until 2015. Among clients reporting methamphetamine injection, there was a shift in the form from base to the higher-potency crystal methamphetamine since 2012. Heroin injection (22.5% service occasions) initially increased (cf. 2007), followed by a decline to 0.77 (95% CI: 0.75, 0.79) in 2015. Significant and sustained increases in OST and other pharmaceutical opioids injection were observed throughout the study period, accounting for 7.2% and 19.8% of total visits, respectively. DISCUSSION AND CONCLUSIONS: The QNSPMDS provides unique, routinely collected, jurisdiction-wide and standardised data on the demographics of people who inject drugs, types of drugs injected and regional variations; these data are essential in informing policy, planning and program implementation. There remains significant opportunity to enhance engagement and linkage to care alongside needle-syringe provision.

Explaining the declining rates of past year cannabis use in Australia: A first pass.

INTRODUCTION AND AIMS: Cannabis use rates in Australia have declined since 2001. No research to date has examined possible reasons, despite evident policy interest in understanding such a positive public health outcome. In a 'first pass' examination, five possible reasons are explored: (i) attitudinal shifts regarding the acceptability of cannabis use; (ii) regulatory or policy changes; (iii) supply/market changes; (iv) changes in other drug use that may operate as substitutes or complements to cannabis; and (v) socio-cultural factors. METHODS: Secondary analyses from three publically available national surveys (the National Drug Strategy Household Survey 2001 to 2013, the Illicit Drug Reporting System 2004 to 2013 and the Illicit Drug Data Report 2002 to 2013) were used to explore the five reasons. RESULTS: It appears that all five explanations are reasonable and have preliminary evidence to indicate they are worth pursuing empirically. Attitudes have not softened towards cannabis in Australia, and regulatory changes appear to have tightened. Perceived purity may have declined, and with stable prices, this suggests an increase in purity-adjusted price that would also be consistent with decreased use. The significant declines in tobacco and alcohol use in Australia, which operate as complements to cannabis, also plausibly account for the significant decrease. DISCUSSION AND CONCLUSIONS: This work suggests future directions for cannabis research in Australia. New multi-disciplinary research that has the potential to explore multiple hypotheses simultaneously is required. [Ritter A, Sotade O. Explaining the declining rates of past year cannabis use in Australia: A first pass. Drug Alcohol Rev 2017;00:000-000].