Exploring anaesthetists' views on the carbon footprint of anaesthesia and identifying opportunities and challenges for reducing its impact on the environment.

A shift in practice by anaesthetists away from anaesthetic gases with high global warming potential towards lower emission techniques (e.g. total intravenous anaesthesia) could result in significant carbon savings for the health system. The purpose of this qualitative interview study was to understand anaesthetists' perspectives on the carbon footprint of anaesthesia, and views on shifting practice towards more environmentally sustainable options. Anaesthetists were recruited from four hospitals in Western Sydney, Australia. Data were organised according to the capability-opportunity-motivation model of behaviour change. Twenty-eight anaesthetists were interviewed (July-September 2021). Participants' age ranged from 29 to 62 years (mean 43 years), 39% were female, and half had completed their anaesthesia training between 2010 and 2019. Challenges to the wider use of greener anaesthetic agents were identified across all components of the capability-opportunity-motivation model: capability (gaps in clinician skills and experience, uncertainty regarding research evidence); opportunity (norms, time, and resource pressures); and motivation (beliefs, habits, responsibility and guilt). Suggestions for encouraging a shift to more environmentally friendly anaesthesia included access to education and training, implementing guidelines and audit/feedback models, environmental restructuring, improving resource availability, reducing low value care, and building the research evidence base on the safety of alternative agents and their impacts on patient outcomes. We identified opportunities and challenges to reducing the carbon footprint of anaesthesia in Australian hospitals by way of system-level and individual behavioural change. Our findings will be used to inform the development of communication and behavioural interventions aiming to mitigate carbon emissions of healthcare.

Health benefits and harms of mammography screening in older women (75+ years)-a systematic review.

BACKGROUND: There is little evidence on the balance between potential benefits and harms of mammography screening in women 75 years and older. The aim of this systematic review was to synthesise the evidence on the outcomes of mammography screening in women aged 75 years and older. METHODS: A systematic review of mammography screening studies in women aged 75 years and over. RESULTS: Thirty-six studies were included in this review: 27 observational studies and 9 modelling studies. Many of the included studies used no or uninformative comparison groups resulting in a potential bias towards the benefits of screening. Despite this, there was mixed evidence about the benefits and harms of continuing mammography screening beyond the age of 75 years. Some studies showed a beneficial effect on breast cancer mortality, and other studies showed no effect on mortality. Some studies showed some harms (false positive tests and recalls) being comparable to those in younger age-groups, with other studies showing increase in false positive screens and biopsies in older age-group. Although reported in fewer studies, there was consistent evidence of increased overdiagnosis in older age-groups. CONCLUSION: There is limited evidence available to make a recommendation for/against continuing breast screening beyond the age of 75 years. Future studies should use more informative comparisons and should estimate overdiagnosis given potentially substantial harm in this age-group due to competing causes of death. This review was prospectively registered with PROSPERO (CRD42020203131).

Environmental impact of cardiovascular healthcare.

IMPORTANCE: The healthcare sector is essential to human health and well-being, yet its significant carbon footprint contributes to climate change-related threats to health. OBJECTIVE: To review systematically published studies on environmental impacts, including carbon dioxide equivalent (CO2e) emissions, of contemporary cardiovascular healthcare of all types, from prevention through to treatment. EVIDENCE REVIEW: We followed the methods of systematic review and synthesis. We conducted searches in Medline, EMBASE and Scopus for primary studies and systematic reviews measuring environmental impacts of any type of cardiovascular healthcare published in 2011 and onwards. Studies were screened, selected and data were extracted by two independent reviewers. Studies were too heterogeneous for pooling in meta-analysis and were narratively synthesised with insights derived from content analysis. FINDINGS: A total of 12 studies estimating environmental impacts, including carbon emissions (8 studies), of cardiac imaging, pacemaker monitoring, pharmaceutical prescribing and in-hospital care including cardiac surgery were found. Of these, three studies used the gold-standard method of Life Cycle Assessment. One of these found the environmental impact of echocardiography was 1%-20% that of cardiac MR (CMR) imaging and Single Photon Emission Tomography (SPECT) scanning. Many opportunities to reduce environmental impacts were identified: carbon emissions can be reduced by choosing echocardiography as the first cardiac test before considering CT or CMR, remote monitoring of pacemaker devices and teleconsultations when clinically appropriate to do so. Several interventions may be effective for reducing waste, including rinsing bypass circuitry after cardiac surgery. Cobenefits included reduced costs, health benefits such as cell salvage blood available for perfusion, and social benefits such as reduced time away from work for patients and carers. Content analysis revealed concern about the environmental impact of cardiovascular healthcare, particularly carbon emissions and a desire for change. CONCLUSIONS AND RELEVANCE: Cardiac imaging, pharmaceutical prescribing and in-hospital care including cardiac surgery have significant environmental impacts, including CO2e emissions which contribute to climate-related threats to human health. Importantly, many opportunities to effectively reduce environmental impacts exist within cardiac care, and can provide economic, health and social cobenefits.

The carbon footprint of pathology testing.

OBJECTIVES: To estimate the carbon footprint of five common hospital pathology tests: full blood examination; urea and electrolyte levels; coagulation profile; C-reactive protein concentration; and arterial blood gases. DESIGN, SETTING: Prospective life cycle assessment of five pathology tests in two university-affiliated health services in Melbourne. We included all consumables and associated waste for venepuncture and laboratory analyses, and electricity and water use for laboratory analyses. MAIN OUTCOME MEASURE: Greenhouse gas footprint, measured in carbon dioxide equivalent (CO2 e) emissions. RESULTS: CO2 e emissions for haematology tests were 82 g/test (95% CI, 73-91 g/test) for coagulation profile and 116 g/test (95% CI, 101-135 g/test) for full blood examination. CO2 e emissions for biochemical tests were 0.5 g/test CO2 e (95% CI, 0.4-0.6 g/test) for C-reactive protein (low because typically ordered with urea and electrolyte assessment), 49 g/test (95% CI, 45-53 g/test) for arterial blood gas assessment, and 99 g/test (95% CI, 84-113 g/test) for urea and electrolyte assessment. Most CO2 e emissions were associated with sample collection (range, 60% for full blood examination to 95% for coagulation profile); emissions attributable to laboratory reagents and power use were much smaller. CONCLUSION: The carbon footprint of common pathology tests was dominated by those of sample collection and phlebotomy. Although the carbon footprints were small, millions of tests are performed each year in Australia, and reducing unnecessary testing will be the most effective approach to reducing the carbon footprint of pathology. Together with the detrimental health and economic effects of unnecessary testing, our environmental findings should further motivate clinicians to test wisely.

Is the risk of cancer in Australia overstated? The importance of competing mortality for estimating lifetime risk.

OBJECTIVES: To calculate lifetime risks of cancer diagnosis and cancer-specific death, adjusted for competing mortality, and to compare these estimates with the corresponding risks published by the Australian Institute of Health and Welfare (AIHW). DESIGN, SETTING: Analysis of publicly available annual AIHW data on age-specific cancer incidence and mortality - for breast cancer, colorectal cancer, prostate cancer, melanoma of the skin, and lung cancer - and all-cause mortality in Australia, 1982-2013. OUTCOME MEASURES: Lifetime risks of cancer diagnosis and mortality (to age 85), adjusted for competing mortality. RESULTS: During 1982-2013, AIHW estimates were consistently higher than our competing mortality-adjusted estimates of lifetime risks of diagnosis and death for all five cancers. Differences between AIHW and adjusted estimates declined with time for breast cancer, prostate cancer, colorectal cancer, and lung cancer (for men only), but remained steady for lung cancer (women only) and melanoma of the skin. In 2013, the respective estimated lifetime risks of diagnosis (AIHW and adjusted) were 12.7% and 12.1% for breast cancer, 18.7% and 16.2% for prostate cancer, 9.0% and 7.0% (men) and 6.4% and 5.5% (women) for colorectal cancer, 7.5% and 6.0% (men) and 4.4% and 4.0% (women) for melanoma of the skin, and 7.6% and 5.8% (men) and 4.5% and 3.9% (women) for lung cancer. CONCLUSION: The method employed in Australia to calculate the lifetime risks of cancer diagnosis and mortality overestimates these risks, especially for men.

Estimating the magnitude of cancer overdiagnosis in Australia.

OBJECTIVES: To estimate the proportion of cancer diagnoses in Australia that might reasonably be attributed to overdiagnosis by comparing current and past lifetime risks of cancer. DESIGN, SETTING, AND PARTICIPANTS: Routinely collected Australian Institute of Health and Welfare national data were analysed to estimate recent (2012) and historical (1982) lifetime risks (adjusted for competing risk of death and changes in risk factors) of diagnoses with five cancers: prostate, breast, renal, thyroid cancers, and melanoma. MAIN OUTCOME MEASURE: Difference in lifetime risks of cancer diagnosis between 1982 and 2012, interpreted as probable overdiagnosis. RESULTS: For women, absolute lifetime risk increased by 3.4 percentage points for breast cancer (invasive cancers, 1.7 percentage points), 0.6 percentage point for renal cancer, 1.0 percentage point for thyroid cancer, and 5.1 percentage points for melanoma (invasive melanoma, 0.7 percentage point). An estimated 22% of breast cancers (invasive cancers, 13%), 58% of renal cancers, 73% of thyroid cancers, and 54% of melanomas (invasive melanoma, 15%) were overdiagnosed, or 18% of all cancer diagnoses (8% of invasive cancer diagnoses). For men, absolute lifetime risk increased by 8.2 percentage points for prostate cancer, 0.8 percentage point for renal cancer, 0.4 percentage point for thyroid cancer, and 8.0 percentage points for melanoma (invasive melanoma, 1.5 percentage points). An estimated 42% of prostate cancers, 42% of renal cancers, 73% of thyroid cancers, and 58% of melanomas (invasive melanomas, 22%) were overdiagnosed, or 24% of all cancer diagnoses (16% of invasive cancer diagnoses). Alternative assumptions slightly modified the estimates for overdiagnosis of breast cancer and melanoma. CONCLUSIONS: About 11 000 cancers in women and 18 000 in men may be overdiagnosed each year. Rates of overdiagnosis need to be reduced and health services should monitor emerging areas of overdiagnosis.

Knowledge of current abortion law and views on abortion law reform: a community survey of NSW residents.

OBJECTIVE: To report results of a community survey of NSW residents' knowledge of current abortion law and views on abortion law reform. METHODS: A total of 1,015 men and women participated. Recruitment and questionnaires were completed anonymously online using survey panel sampling. RESULTS: Seventy-six per cent of respondents were unaware that abortion remains a criminal offence in the Crimes Act 1900 (NSW) and 73% thought it should be decriminalised and regulated as a healthcare service. Support for decriminalisation was consistent across genders, age groups, residents of metropolitan/regional and rural areas and levels of education. Support was strong for women seeking abortion to be protected from harassment (89%) and for protester exclusion zones around clinics (81%), with support for these measures significantly stronger among regional/rural residents than Sydney-based respondents. CONCLUSIONS: Abortion law in NSW is out of step with contemporary community views. Residents are largely unaware that it remains a criminal offence and, when informed, support decriminalisation. There is strong support for legal changes to protect women from harassment and to provide protester exclusion zones around abortion clinics. Implications for public health: Abortion law reform would reduce current inequities of access, be democratic and support women's autonomy and reproductive rights.

Population attributable fractions of perinatal outcomes for nulliparous women associated with overweight and obesity, 1990-2014.

OBJECTIVE: To examine the prevalence across 25 years of overweight and obesity among nulliparous Australian women during early pregnancy; to estimate the proportions of adverse perinatal outcomes attributable to overweight and obesity in this population. DESIGN: Cohort study; retrospective analysis of electronic maternity data. Setting, participants: 42 582 nulliparous women with singleton pregnancies giving birth at the Royal Prince Alfred Hospital, an urban teaching hospital in Sydney, January 1990 - December 2014. MAIN OUTCOME MEASURES: Maternal body mass index (BMI), socio-demographic characteristics, and selected maternal, birth and neonatal outcomes; the proportion of adverse perinatal outcomes that could be averted by reducing the prevalence of overweight and obesity in women prior to first pregnancies (population attributable fraction, PAF). RESULTS: The prevalence of overweight among nulliparous pregnant women increased from 12.7% (1990-1994) to 16.4% (2010-2014); the prevalence of obesity rose from 4.8% to 7.3% in the same period, while the proportion with normal range BMIs fell from 73.5% to 68.2%. The PAFs for key adverse maternal and neonatal outcomes increased across the study period; during 2010-2014, 23.8% of pre-eclampsia, 23.4% of fetal macrosomia, and 17.0% of gestational diabetes were attributable to overweight and obesity. Were overweight and obese women to have moved down one BMI category during 2010-2014, 19% of pre-eclampsia, 15.9% of macrosomia, 14.2% of gestational diabetes, 8.5% of caesarean deliveries, 7.1% of low for gestational age birthweight, 6.8% of post partum haemorrhage, 6.5% of admissions to special care nursery, 5.8% of prematurity, and 3.8% of fetal abnormality could have been averted. CONCLUSIONS: Over the past 25 years, the proportions of adverse perinatal outcomes attributable to overweight and obesity have risen with the increasing prevalence of maternal overweight and obesity. A substantial proportion of these outcomes might be averted with obesity prevention strategies that reduce pre-pregnancy maternal weight.

"Standard Care" in Cancer Clinical Trials: An Analysis of Care Provided to Women in the Control Arms of Breast Cancer Clinical Trials.

Background: For trials to validly evaluate new treatments, comparison against the best existing alternative treatment is essential. We reviewed the care provided to women in control arms of breast cancer clinical trials to estimate the proportion consistent with the standard of care as defined in clinical guidelines. Methods: We analyzed phase III randomized controlled breast cancer trials comparing drug treatments with "standard care," enrolling between 2004 and 2014, and registered on ClinicalTrials.gov Our primary outcome was the proportion of trials in which treatment in the control arm was consistent with concurrent NCCN Guidelines. A secondary analysis assessed trials recruiting outside the United States that provided control group therapy not consistent with NCCN Guidelines, comparing them with the German Gynecological Oncology Group (AGO) guidelines. We assessed associations between the primary outcome and a priori selected trial characteristics. Results: This study included 210 trials that recruited 229,182 women worldwide; 29% of trials (60/210) did not provide control group treatment that was consistent with NCCN Guidelines. For trials not recruiting in the United States, results were similar; in 21% of trials, control arm treatment was inconsistent with both AGO and NCCN Guidelines. Factors significantly associated with offering control arm treatment that were inconsistent with guidelines were time period (later trials were less likely to be consistent), breast cancer stage and type (trials in early-stage breast cancer and estrogen receptor-negative disease were less likely consistent), and recruitment in ≥4 countries and recruitment outside the United States. Conclusions: To ensure that clinical trials achieve their goal of obtaining the best information to guide patient treatment, the question of how investigators chose and describe "standard care" for control arm participants warrants further investigation.

A theoretical analysis showed that blinding cannot eliminate potential for bias associated with beliefs about allocation in randomized clinical trials.

OBJECTIVES: To explore the theoretical justification for blinding in randomized trials and make recommendations concerning the implementation and interpretation of blinded randomized trials. STUDY DESIGN AND SETTING: A theoretical analysis was conducted of the potential for bias in randomized trials with successful blinding (ie, trials in which beliefs about allocation to treatment or control groups are independent of actual allocation). The analysis identified conditions that must be satisfied to ensure that blinding eliminates the potential for bias associated with beliefs about allocation. RESULTS: Even when beliefs about allocation are independent of actual allocation, they can still cause bias. The potential for bias is eliminated when the belief is uniformly one of complete ambivalence about allocation. CONCLUSION: Even when blinding succeeds in making beliefs about allocation independent of actual allocation, beliefs about allocation may still cause bias. It is difficult to determine the extent of bias in any particular trial. Bias could be eliminated by establishing a state of complete ambivalence about the allocation of every trial participant, but universal ambivalence may be difficult to achieve and may reduce the generalizability of the trial's findings.

Online prostate cancer screening decision aid for at-risk men: a randomized trial.

OBJECTIVE: This study examines the efficacy of an online screening decision aid (DA) for men with a family history of prostate cancer. METHODS: Unaffected Australian men (40-79 years) with at least one affected relative completed the first online questionnaire, were randomized to read either the tailored DA (intervention) or nontailored information about prostate cancer screening (control), then completed a questionnaire postreading and 12 months later. The primary outcome was decisional conflict regarding prostate specific antigen (PSA) testing. The impact of the DA on longitudinal outcomes was analyzed by using random intercept mixed effects models. Logistic and linear regressions were used to analyze the impact of the DA on screening behavior and decision regret. Stage of decision-making was tested as a moderator for decisional conflict and decision regret. The frequency of online material access was recorded. RESULTS: The DA had no effect on decisional conflict, knowledge, inclination toward PSA testing, accuracy of perceived risk, or screening behavior. However, among men considering PSA testing, those who read the DA had lower decision regret compared with men who read the control materials, ß = 0.34, p < .001, 95% confidence interval (CI) = [.22, .53]. CONCLUSIONS: This is the first study to our knowledge to evaluate the uptake and efficacy of an online screening DA among men with a family history of prostate cancer. Men who were undecided about screening at baseline benefitted from the DA, experiencing less regret 12 months later. In relation to decisional conflict, the control materials may have operated as a less complex and equally informative DA.

Identifying and prioritising gaps in colorectal cancer trials research in Australia.

OBJECTIVES: To identify gaps in colorectal cancer clinical trials research in Australia and to suggest and prioritise trials to fill those gaps. DESIGN, SETTING AND PARTICIPANTS: Retrospective review of colorectal cancer trial activity from 1 January 2005 to 1 July 2011 in Australia and internationally, followed by a consensus meeting of consumers, health care professionals, researchers and funding agencies. MAIN OUTCOME MEASURES: Proportion of Phase III and randomised clinical trials in the areas of prevention, screening, surgery, adjuvant therapy, advanced disease and behavioural interventions, and priority areas of research identified by participants at the consensus meeting. RESULTS: The registry search identified 76 colorectal cancer clinical trials (all phases) registered in Australia from 1 January 2005 to 1 July 2011, of which 51 were Phase III or randomised, and 323 Phase III and randomised trials registered worldwide. In Australia, most trials were in advanced colorectal cancer (32), screening (10), and behavioural interventions (9). Worldwide, most Phase III or randomised trials were in advanced disease (94, 29.1%), surgery (64, 19.8%), behavioural interventions (38, 11.8%), and screening (30, 9.3%). At the consensus meeting, all participant groups emphasised the need for research in secondary prevention, screening, individualised treatments and follow-up care after treatment for colorectal cancer. CONCLUSIONS: There is a mismatch between the high proportion of registered trials in advanced colorectal cancer and the areas of priority identified. The development of specific trials in these priority areas depends on the availability of funding and the existence of plausible interventions likely to improve patient outcomes.