2023 Australian guideline for assessing and managing cardiovascular disease risk

INTRODUCTION

The 2023 Australian guideline for assessing and managing cardiovascular disease risk provides updated evidence-based recommendations for the clinical assessment and management of cardiovascular disease (CVD) risk for primary prevention. It includes the new Australian CVD risk calculator (Aus CVD Risk Calculator), based on an equation developed from a large New Zealand cohort study, customised and recalibrated for the Australian population. The new guideline replaces the 2012 guideline that recommended CVD risk assessment using the Framingham risk equation.

MAIN RECOMMENDATIONS

The new guideline recommends CVD risk assessment in people without known CVD: all people aged 45-79 years, people with diabetes from 35 years, and First Nations people from 30 years. The new Aus CVD Risk Calculator should be used to estimate and categorise CVD risk into low (< 5% risk over five years), intermediate (5% to < 10% risk over five years) or high risk (≥ 10% over five years). The following reclassification factors may be applied to recategorise calculated risk to improve accuracy of risk prediction, particularly in individuals close to a risk threshold: Indigenous status/ethnicity, estimated glomerular filtration rate, urine albumin to creatinine ratio measurements, severe mental illness, coronary artery calcium score and family history of premature CVD. A variety of communication formats is available to communicate CVD risk to help enable shared decision making. Healthy lifestyle modification, including smoking cessation, nutrition, physical activity and limiting alcohol, is encouraged for all individuals. Blood pressure-lowering and lipid-modifying pharmacotherapies should be prescribed for high risk and considered for intermediate risk individuals, unless contraindicated or clinically inappropriate. Reassessment of CVD risk should be considered within five years for individuals at low risk and within two years for those with intermediate risk. Reassessment of CVD risk is not recommended for individuals at high risk. CHANGES IN ASSESSMENT AND MANAGEMENT AS A RESULT OF THE GUIDELINE: The updated guideline recommends assessment over a broader age range and uses the Aus CVD Risk Calculator, which replaces the previous Framingham-based equation. It incorporates new variables: social disadvantage, diabetes-specific risk markers, diagnosis of atrial fibrillation and use of blood pressure-lowering and lipid-modifying therapies. Reclassification factors are also a new addition. Updated risk categories and thresholds are based on the new Aus CVD Risk Calculator. The proportion of the population in the high risk category (≥ 10% over five years) is likely to be broadly comparable to more than 15% risk from the Framingham-based equation. The full guideline and Aus CVD Risk Calculator can be accessed at www.cvdcheck.org.au.

Impact of weighting on the association between sociodemographic characteristics, health behaviours and cancer, cardiovascular and all-cause mortality in the Australian 45 and Up Study

BACKGROUND

Weighting can improve study estimate representativeness. We examined the impact of weighting on associations between participants' characteristics and cancer, cardiovascular and all-cause mortality in the Australian 45 and Up Study cohort.

METHODS

Raking weighted cohort data to the 2006 Australian population for seven sociodemographic characteristics. Deaths were ascertained via linkage to routinely collected data. Cox's proportional hazards regression quantified associations between 11 sociodemographic and health characteristics and cancer, cardiovascular and all-cause mortality. The ratios of hazard ratios (RHRs) compared unweighted and weighted estimates.

RESULTS

Among 195,052 included participants (median follow-up 11.4 years), there were 7200 cancer, 5912 cardiovascular and 21,840 all-cause deaths. Overall, 102/111 (91.9%) weighted HRs did not differ significantly from unweighted HRs (100%, 86.5% and 89.2% of 37 HRs for cancer, cardiovascular and all-cause mortality, respectively). Significant differences included a somewhat stronger association between single/widowed/divorced (versus married/de-facto) and cardiovascular mortality (unweighted HR=1.25 (95%CI:1.18-1.32), weighted HR=1.33 (95%CI:1.24-1.42), RHR=1.06 (95%CI:1.02-1.11)); and between no school certificate/qualification (versus university degree) and all-cause mortality (unweighted HR=1.21 (95%CI:1.15-1.27), weighted HR=1.28 (95%CI:1.19-1.38), RHR=1.06 (95%CI:1.03-1.10)).

CONCLUSION

Our results support the generalisability of most estimates of associations in the 45 and Up Study, particularly in relation to cancer mortality. Slight distortion of a few associations with cardiovascular or all-cause mortality were observed.

Cardiometabolic health markers among Aboriginal adolescents from the Next Generation Youth Wellbeing Cohort Study

OBJECTIVE

The objective of this study was to investigate cardiometabolic health markers among Aboriginal adolescents aged 10-24 years and relationships with age, gender, and body composition.

METHODS

Baseline data (2018-2020) from the Next Generation Youth Wellbeing Cohort Study (Western Australia, New South Wales, and Central Australia) on clinically assessed body mass index, waist/height ratio, blood pressure, glycated haemoglobin (HbA1c), total and high-density lipoprotein cholesterol, total/high-density lipoprotein cholesterol ratio, and triglycerides were analysed.

RESULTS

Among 1100 participants, the proportion with individual health markers within the ideal range ranged from 59% for total cholesterol to 91% for HbA1c. Four percent had high blood pressure, which was more common with increasing age and among males; 1% had HbA1c indicative of diabetes. Healthier body composition (body mass index and waist/height ratio) was associated with having individual health markers in the ideal range and with an ideal cardiometabolic profile.

CONCLUSIONS

Most Aboriginal adolescents in this study had cardiometabolic markers within the ideal range, though markers of high risk were present from early adolescence. Ideal health markers were more prevalent among those with healthy body composition.

IMPLICATIONS FOR PUBLIC HEALTH

Specific screening and management guidelines for Aboriginal adolescents and population health initiatives that support maintenance of healthy body composition could help improve cardiometabolic health in this population.

Electronic cigarette social norms among adolescents in New South Wales, Australia

The use of electronic cigarettes (e-cigarettes) is common and increasing, especially among youth. In 2022/2023, 30% of 12- to 17-year-olds reported ever using e-cigarettes in Australia-a >50% increase from 2017 (14%). Several adverse e-cigarette health effects have been identified and most effects remain unknown. Social norms, rules that govern social behaviours, are associated with current and future adolescent e-cigarette use. Understanding social norms in Australian adolescents is critical to the development of targeted and effective e-cigarette prevention activities. This study aims to explore e-cigarette social norms among adolescents living in New South Wales, Australia. A total of 32 online single or paired semi-structured qualitative interviews were conducted involving 46 participants aged 14-17 years, as part of the Generation Vape project. Reflexive thematic analysis was applied within a constructivist perceptive. Adolescents perceived e-cigarettes use as prolific among their peers, with use considered common, acceptable and normal. Fuelled by social exposure to e-cigarettes, 'everyone' was generally thought to be using them (descriptive norms). E-cigarette use was considered so entrenched that it was part of adolescent identity, with abstinence regarded as atypical. Use was driven by an internalised desire to fit it (injunctive norm), rather than being attributed to overt/external 'peer-pressure'. Positive e-cigarette norms exist among Australian adolescents with norm formation strongly influenced by social exposure, including e-cigarette promotion. Prevention efforts should include limiting adolescent exposure to e-cigarette marketing to help redefine existing pro-e-cigarette social norms and protect health.

Trends and projections of cause-specific premature mortality in Australia to 2044: a statistical modelling study

Background

Long-term projections of premature mortality (defined as deaths age <75 years) help to inform decisions about public health priorities. This study aimed to project premature mortality rates in Australia to 2044, and to estimate numbers of deaths and potential years of life lost (PYLL) due to premature mortality overall and for 59 causes.

Methods

We examined the past trends in premature mortality rates using Australian mortality data by sex, 5-year age group and 5-year calendar period up to 2019. Cigarette smoking exposure data (1945-2019) were included to project lung cancer mortality. Age-period-cohort or generalised linear models were developed and validated for each cause to project premature mortality rates to 2044.

Findings

Over the 25-year period from 1990-1994 to 2015-2019, there was a 44.4% decrease in the overall age-standardised premature mortality rate. This decline is expected to continue, from 162.4 deaths/100,000 population in 2015-2019 to 141.7/100,000 in 2040-2044 (12.7% decrease). Despite declining rates, total numbers of premature deaths are projected to increase by 22.8%, rising from 272,815 deaths in 2015-2019 to 334,894 deaths in 2040-2044. This is expected to result in 1.58 million premature deaths over the 25-year period 2020-2044, accounting for 24.5 million PYLL. Of the high-level cause categories, cancer is projected to remain the most common cause of premature death in Australia by 2044, followed by cardiovascular disease, external causes (including injury, poisoning, and suicide), and respiratory diseases.

Interpretation

Despite continuously declining overall premature mortality rates, the total number of premature deaths in Australia is projected to remain substantial, and cancer will continue to be the leading cause. These projections can inform the targeting of public health efforts and can serve as benchmarks against which to measure the impact of future interventions. They emphasise the ongoing importance of accelerating the prevention, early detection, and treatment of key health conditions.

Funding

No funding was provided for this study.

DENND6A links Arl8b to a Rab34/RILP/dynein complex, regulating lysosomal positioning and autophagy

Lysosomes help maintain cellular proteostasis, and defects in lysosomal positioning and function can cause disease, including neurodegenerative disorders. The spatiotemporal distribution of lysosomes is regulated by small GTPases including Rabs, which are activated by guanine nucleotide exchange factors (GEFs). DENN domain proteins are the largest family of Rab GEFs. Using a cell-based assay, we screened DENND6A, a member of the DENN domain protein family against all known Rabs and identified it as a potential GEF for 20 Rabs, including Rab34. Here, we demonstrate that DENND6A activates Rab34, which recruits a RILP/dynein complex to lysosomes, promoting lysosome retrograde transport. Further, we identify DENND6A as an effector of Arl8b, a major regulatory GTPase on lysosomes. We demonstrate that Arl8b recruits DENND6A to peripheral lysosomes to activate Rab34 and initiate retrograde transport, regulating nutrient-dependent lysosomal juxtanuclear repositioning. Loss of DENND6A impairs autophagic flux. Our findings support a model whereby Arl8b/DENND6A/Rab34-dependent lysosomal retrograde trafficking controls autophagy.

Health behaviours associated with healthy body composition among Aboriginal adolescents in Australia in the 'Next Generation: Youth Well-being study'

This study described the distribution of healthy body composition among Aboriginal adolescents in Australia aged 10-24 years and examined associations with health behaviours and self-rated health. Data were cross-sectional from the 'Next Generation: Youth Well-being study' baseline (N = 1294). We used robust Poisson regression to quantify associations of self-reported health behaviours (physical activity, screen time, sleep, consumption of vegetables, fruit, soft drinks and fast food, and tobacco smoking and alcohol) and self-rated health to healthy body mass index (BMI) and waist/height ratio (WHtR). Overall, 48% of participants had healthy BMI and 64% healthy WHtR, with healthy body composition more common among younger adolescents. Higher physical activity was associated with healthy body composition (5-7 days last week vs none; adjusted prevalence ratio (aPR) healthy BMI 1.31 [95% CI 1.05-1.64], and healthy WHtR 1.30 [1.10-1.54]), as was recommended sleep duration (vs not; aPR healthy BMI 1.56 [1.19-2.05], and healthy WHtR 1.37 [1.13-1.67]). There was a trend for higher proportion of healthy body composition with more frequent fast food consumption. Healthy body composition was also associated with higher self-rated health ('very good/excellent' vs 'poor/fair'; aPR healthy BMI 1.87 [1.45-2.42], and healthy WHtR 1.71 [1.40-2.10]). Culturally appropriate community health interventions with a focus on physical activity and sleep may hold promise for improving body composition among Aboriginal adolescents.

Pain and its interference with daily living in relation to cancer: a comparative population-based study of 16,053 cancer survivors and 106,345 people without cancer

BACKGROUND

Pain is a common, debilitating, and feared symptom, including among cancer survivors. However, large-scale population-based evidence on pain and its impact in cancer survivors is limited. We quantified the prevalence of pain in community-dwelling people with and without cancer, and its relation to physical functioning, psychological distress, and quality of life (QoL).

METHODS

Questionnaire data from participants in the 45 and Up Study (Wave 2, n = 122,398, 2012-2015, mean age = 60.8 years), an Australian population-based cohort study, were linked to cancer registration data to ascertain prior cancer diagnoses. Modified Poisson regression estimated age- and sex-adjusted prevalence ratios (PRs) for bodily pain and pain sufficient to interfere with daily activities (high-impact pain) in people with versus without cancer, for 13 cancer types, overall and according to clinical, personal, and health characteristics. The relation of high-impact pain to physical and mental health outcomes was quantified in people with and without cancer.

RESULTS

Overall, 34.9% (5,436/15,570) of cancer survivors and 31.3% (32,471/103,604) of participants without cancer reported bodily pain (PR = 1.07 [95% CI = 1.05-1.10]), and 15.9% (2,468/15,550) versus 13.1% (13,573/103,623), respectively, reported high-impact pain (PR = 1.13 [1.09-1.18]). Pain was greater with more recent cancer diagnosis, more advanced disease, and recent cancer treatment. High-impact pain varied by cancer type; compared to cancer-free participants, PRs were: 2.23 (1.71-2.90) for multiple myeloma; 1.87 (1.53-2.29) for lung cancer; 1.06 (0.98-1.16) for breast cancer; 1.05 (0.94-1.17) for colorectal cancer; 1.04 (0.96-1.13) for prostate cancer; and 1.02 (0.92-1.12) for melanoma. Regardless of cancer diagnosis, high-impact pain was strongly related to impaired physical functioning, psychological distress, and reduced QoL.

CONCLUSIONS

Pain is common, interfering with daily life in around one-in-eight older community-dwelling participants. Pain was elevated overall in cancer survivors, particularly for certain cancer types, around diagnosis and treatment, and with advanced disease. However, pain was comparable to population levels for many common cancers, including breast, prostate and colorectal cancer, and melanoma.

Evidence supporting the choice of a new cardiovascular risk equation for Australia

This article reviews the risk equations recommended for use in international cardiovascular disease (CVD) primary prevention guidelines and assesses their suitability for use in Australia against a set of a priori defined selection criteria. The review and assessment were commissioned by the National Heart Foundation of Australia on behalf of the Australian Chronic Disease Prevention Alliance to inform recommendations on CVD risk estimation as part of the 2023 update of the Australian CVD risk assessment and management guidelines. Selected international risk equations were assessed against eight selection criteria: development using contemporary data; inclusion of established cardiovascular risk factors; inclusion of ethnicity and deprivation measures; prediction of a broad selection of fatal and non-fatal CVD outcomes; population representativeness; model performance; external validation in an Australian dataset; and the ability to be recalibrated or modified. Of the ten risk prediction equations reviewed, the New Zealand PREDICT equation met seven of the eight selection criteria, and met additional usability criteria aimed at assessing the ability to apply the risk equation in practice in Australia.

Ear health and hearing in urban Aboriginal children

OBJECTIVE

Evaluate ear health and hearing among urban Aboriginal children and quantify relationships with child, family and social factors.

METHODS

Baseline questionnaire and ear health examinations from 1430 children with diagnoses (0.5-18 years) attending Aboriginal Health Services enrolled in SEARCH. Ear health outcomes were Otitis Media (OM), and hearing loss (three-frequency average hearing loss >20dB) diagnosed using pneumatic otoscopy, tympanometry, and audiometry.

RESULTS

Half the children 0.5-3 years had OM (51.5%, 136/264). One third 0.5-18 years (30.4%; 435/1430) had OM, including 1.8% (26/1430) with perforation (0.8% chronic suppurative OM, 0.6% dry perforation and 0.4% acute OM with perforation). One quarter 0.5-18 years (25.7%; 279/1087) had hearing loss; 12.4% unilateral, 13.2% bilateral (70.6% with bilateral loss had concurrent OM). OM was associated with: younger age (0.5-<3 years versus 6-18 years) age-sex-site; adjusted prevalence ratio (aPR)=2.64, 95%, 2.18-3.19); attending childcare/preschool (aPR=1.24, 95%CI, 1.04-1.49); foster care (aPR=1.40, 95%CI, 1.10-1.79); previous ear infection/s (aPR=1.68, 95%CI, 1.42-1.98); and ≥2 people/bedroom (aPR=1.66, 95%CI, 1.24-2.21). Hearing impairment was associated with younger age (0.5-<6 years vs. ≥6 years aPR=1.89, 95%CI, 1.40-2.55) and previous ear infection (aPR=1.87, 95%CI, 1.31-2.68).

CONCLUSIONS

Half the urban Aboriginal children in this cohort had OM and two-thirds with hearing impairment had OM.

IMPLICATIONS FOR PUBLIC HEALTH

Findings highlight importance of early detection and support for ear health, particularly in pre-school-aged children with risk factors.

Application of a revised model for coping with advanced cancer to qualitatively explore lung cancer survivors' experiences of ongoing physical effects, novel treatments, uncertainty, and coping

PURPOSE

Lung cancer remains underrepresented in cancer survivorship research. This study aimed to understand survivors' physical/psychological challenges, experiences of immunotherapy (IO) and targeted therapy (TT), and psychological adjustment through application of the Roberts et al. (2017) advanced cancer adaptation of Folkman and Greer's appraisal and coping model.

METHODS

Adults 6-24 months post-initial treatment completion were recruited via an Australian cohort study. Participant demographic, clinical, quality of life, and distress data were obtained through the cohort database. Qualitative interviews were conducted and analyzed using Framework methods. Roberts et al. (2017)'s model informed data interpretation and presentation.

RESULTS

Twenty interviews were conducted (10 females; average age 69 years). Participants' diagnostic stages varied (stage I = 2, stage II = 4, stage III = 8, stage IV = 6); most had received IO/TT (n = 14) and were on average 17 months (range 10-24) post-diagnosis. Three themes were identified and mapped to the Roberts' framework: (1) Ongoing illness events: most participants reported functioning well despite ongoing physical effects. Those on IO/TT reported side effects; some were unexpected/serious. (2) Adjusting to life with lung cancer: most expressed hope for the future while simultaneously preparing for disease progression. Those receiving IO/TT experienced uncertainty given limited survival information. (3) Learning to live with lung cancer: participants described emotion, problem, and meaning based on coping strategies.

CONCLUSIONS

Findings may guide development of supportive care resources/interventions focused on uncertainty, IO/TT communication and decision-making, and coping.

IMPLICATIONS FOR CANCER SURVIVORS

Many people with lung cancer are living well with their ongoing illness. Despite challenges, many survivors are adapting to issues as they arise and are maintaining a sense of hope and optimism.

DENND2B activates Rab35 at the intercellular bridge, regulating cytokinetic abscission and tetraploidy

Cytokinesis relies on membrane trafficking pathways regulated by Rabs and guanine nucleotide exchange factors (GEFs). During cytokinesis, the intercellular cytokinetic bridge (ICB) connecting daughter cells undergoes abscission, which requires actin depolymerization. Rab35 recruits MICAL1 to oxidize and depolymerize actin filaments. We show that DENND2B, a protein linked to cancer and congenital disorders, functions as a Rab35 GEF, recruiting and activating Rab35 at the ICB. DENND2B's N-terminal region also interacts with an active form of Rab35, suggesting that DENND2B is both a Rab35 GEF and effector. Knockdown of DENND2B delays abscission, leading to multinucleated cells and filamentous actin (F-actin) accumulation at the ICB, impairing recruitment of ESCRT-III at the abscission site. Additionally, F-actin accumulation triggers the formation of a chromatin bridge, activating the NoCut/abscission checkpoint, and DENND2B knockdown activates Aurora B kinase, a hallmark of checkpoint activation. Thus, our study identifies DENND2B as a crucial player in cytokinetic abscission.

Cumulative incidence of child protection system contacts among a cohort of Western Australian Aboriginal children born 2000 to 2013

BACKGROUND

Reducing the over-representation of Aboriginal children in the child protection system is a key target for the Australian government.

OBJECTIVE

We aimed to provide more recent evidence on the population-level cumulative incidence of contacts for Aboriginal children with child protective services (CPS) in Western Australia (WA).

PARTICIPANTS AND SETTING

Linked administrative data was provided for WA CPS between 2000 and 2015 for 33,709 Aboriginal children born in WA between 2000 and 2013.

METHODS

Descriptive summaries and cumulative incidence estimates were used to examine changes in CPS contact trends over time and within sibling groups.

RESULTS

There was an increase in early-childhood contacts for children born more recently, with 7.6 % and 2.3 % of children born in 2000-2001 having a notification and placement in out-of-home care by age one, respectively, compared to 15.1 % and 4.3 % of children born in 2012-2013. Among sibling groups where at least one sibling had a CPS contact, approximately half of children had their first contacts on the same date as another sibling. For children born after one of their siblings had been placed in out-of-home care, 31.9 % had themselves been placed in out-of-home care by age one.

CONCLUSIONS

Multiple children tend to be placed into out-of-home care when at least one sibling is, which is likely to have a significant impact on families affected. The additional risk of placement also carries over to children born after the first removal in a sibling group, highlighting the need for further support to prevent future removals.

Fifty-year forecasts of daily smoking prevalence: can Australia reach 5% by 2030?

OBJECTIVE

To compare 50-year forecasts of Australian tobacco smoking rates in relation to trends in smoking initiation and cessation and in relation to a national target of ≤5% adult daily prevalence by 2030.

METHODS

A compartmental model of Australian population daily smoking, calibrated to the observed smoking status of 229 523 participants aged 20-99 years in 26 surveys (1962-2016) by age, sex and birth year (1910-1996), estimated smoking prevalence to 2066 using Australian Bureau of Statistics 50-year population predictions. Prevalence forecasts were compared across scenarios in which smoking initiation and cessation trends from 2017 were continued, kept constant or reversed.

RESULTS

At the end of the observation period in 2016, model-estimated daily smoking prevalence was 13.7% (90% equal-tailed interval (EI) 13.4%-14.0%). When smoking initiation and cessation rates were held constant, daily smoking prevalence reached 5.2% (90% EI 4.9%-5.5%) after 50 years, in 2066. When initiation and cessation rates continued their trajectory downwards and upwards, respectively, daily smoking prevalence reached 5% by 2039 (90% EI 2037-2041). The greatest progress towards the 5% goal came from eliminating initiation among younger cohorts, with the target met by 2037 (90% EI 2036-2038) in the most optimistic scenario. Conversely, if initiation and cessation rates reversed to 2007 levels, estimated prevalence was 9.1% (90% EI 8.8%-9.4%) in 2066.

CONCLUSION

A 5% adult daily smoking prevalence target cannot be achieved by the year 2030 based on current trends. Urgent investment in concerted strategies that prevent smoking initiation and facilitate cessation is necessary to achieve 5% prevalence by 2030.

Kulay Kalingka, a national cohort study of Aboriginal and Torres Strait Islander peoples' cancer experiences: a study protocol

INTRODUCTION

Aboriginal and Torres Strait Islander peoples are the First Peoples of Australia. Since settler colonisation, Aboriginal and Torres Strait Islander peoples have experienced disparities in health outcomes, including cancer, when compared with non-Indigenous Australians, including higher cancer incidence and mortality rates, and lower participation in cancer screening programmes. Data to monitor and improve outcomes are limited.

AIMS, METHOD AND ANALYSIS

The Kulay Kalingka Study will be a national cohort study aiming to understand Aboriginal and Torres Strait Islander people's beliefs about cancer and experiences with cancer care and treatment, and to improve experiences and outcomes. It will be nested within the Mayi Kuwayu Study, a national community-controlled cohort study of Aboriginal and Torres Strait Islander people (n>11 000), with supplementary in-community recruitment.Mayi Kuwayu Study participants aged ≥18 years who consented to being recontacted, and a diversity of local community members will be invited to participate through completing a questionnaire relevant to their cancer status, aiming to recruit 2800 participants without prior doctor-diagnosed cancer and 700 with a cancer diagnosis.This community-driven data will enable monitoring and reporting of national trends over time and will guide national cancer control research, policy and clinical care, to improve outcomes for Aboriginal and Torres Strait Islander peoples.

ETHICS AND DISSEMINATION

The Kulay Kalingka Study has ethics approval from Australian Institute of Aboriginal and Torres Strait Islander Studies (#EO324-20220414 and REC-0121) and the Australian National University (#2022/465). The Kulay Kalingka Study is being developed with Aboriginal and Torres Strait Islander communities, following the Maiam nayri Wingara Indigenous Data Sovereignty Collective principles. Meaningful, accessible and culturally adapted study findings will be disseminated to Aboriginal and Torres Strait Islander communities through activities including community workshops, reports and feedback sheets, and in other ways as determined by the community. We will also return data to participating communities.

Analysis of Multiple Causes of Death: A Review of Methods and Practices

BACKGROUND

Research and reporting of mortality indicators typically focus on a single underlying cause of death selected from multiple causes recorded on a death certificate. The need to incorporate the multiple causes in mortality statistics-reflecting increasing multimorbidity and complex causation patterns-is recognized internationally. This review aims to identify and appraise relevant analytical methods and practices related to multiple causes.

METHODS

We searched Medline, PubMed, Scopus, and Web of Science from their incept ion to December 2020 without language restrictions, supplemented by consultation with international experts. Eligible articles analyzed multiple causes of death from death certificates. The process identified 4,080 items of which we reviewed 434 full-text articles.

RESULTS

Most articles we reviewed (76%, n = 332) were published since 2001. The majority of articles examined mortality by "any- mention" of the cause of death (87%, n = 377) and assessed pairwise combinations of causes (57%, n = 245). Since 2001, applications of methods emerged to group deaths based on common cause patterns using, for example, cluster analysis (2%, n = 9), and application of multiple-cause weights to re-evaluate mortality burden (1%, n = 5). We describe multiple-cause methods applied to specific research objectives for approaches emerging recently.

CONCLUSION

This review confirms rapidly increasing international interest in the analysis of multiple causes of death and provides the most comprehensive overview, to our knowledge, of methods and practices to date. Available multiple-cause methods are diverse but suit a range of research objectives. With greater availability of data and technology, these could be further developed and applied across a range of settings.

Electronic cigarettes and health outcomes: umbrella and systematic review of the global evidence

OBJECTIVE

To review and synthesise the global evidence regarding the health effects of electronic cigarettes (e-cigarettes, vapes).

STUDY DESIGN

Umbrella review (based on major independent reviews, including the 2018 United States National Academies of Sciences, Engineering, and Medicine [NASEM] report) and top-up systematic review of published, peer-reviewed studies in humans examining the relationship of e-cigarette use to health outcomes published since the NASEM report.

DATA SOURCES

Umbrella review: eight major independent reviews published 2017-2021. Systematic review: PubMed, MEDLINE, Scopus, Web of Science, the Cochrane Library, and PsycINFO (articles published July 2017 - July 2020 and not included in NASEM review).

DATA SYNTHESIS

Four hundred eligible publications were included in our synthesis: 112 from the NASEM review, 189 from our top-up review search, and 99 further publications cited by other reviews. There is conclusive evidence linking e-cigarette use with poisoning, immediate inhalation toxicity (including seizures), and e-cigarette or vaping product use-associated lung injury (EVALI; largely but not exclusively for e-liquids containing tetrahydrocannabinol and vitamin E acetate), as well as for malfunctioning devices causing injuries and burns. Environmental effects include waste, fires, and generation of indoor airborne particulate matter (substantial to conclusive evidence). There is substantial evidence that nicotine e-cigarettes can cause dependence or addiction in non-smokers, and strong evidence that young non-smokers who use e-cigarettes are more likely than non-users to initiate smoking and to become regular smokers. There is limited evidence that freebase nicotine e-cigarettes used with clinical support are efficacious aids for smoking cessation. Evidence regarding effects on other clinical outcomes, including cardiovascular disease, cancer, development, and mental and reproductive health, is insufficient or unavailable.

CONCLUSION

E-cigarettes can be harmful to health, particularly for non-smokers and children, adolescents, and young adults. Their effects on many important health outcomes are uncertain. E-cigarettes may be beneficial for smokers who use them to completely and promptly quit smoking, but they are not currently approved smoking cessation aids. Better quality evidence is needed regarding the health impact of e-cigarette use, their safety and efficacy for smoking cessation, and effective regulation.

REGISTRATION

Systematic review: PROSPERO, CRD42020200673 (prospective).

The future burden of oesophageal and stomach cancers attributable to modifiable behaviours in Australia: a pooled cohort study

BACKGROUND

We quantified the individual and joint contribution of contemporaneous causal behavioural exposures on the future burden of oesophageal and stomach cancers and their subtypes and assessed whether these burdens differ between population groups in Australia, as such estimates are currently lacking.

METHODS

We combined hazard ratios from seven pooled Australian cohorts (N = 367,058) linked to national cancer and death registries with exposure prevalence from the 2017-2018 National Health Survey to estimate Population Attributable Fractions (PAFs) with 95% confidence intervals (CIs), accounting for competing risk of death.

RESULTS

Current and past smoking explain 35.2% (95% CI = 11.7-52.4%), current alcohol consumption exceeding three drinks/day 15.7% (95% CI = 0.9-28.4%), and these exposures jointly 41.4% (95% CI = 19.8-57.3%) of oesophageal squamous cell carcinomas in Australia. Current and past smoking contribute 38.2% (95% CI = 9.4-57.9%), obesity 27.0% (95% CI = 0.6-46.4%), and these exposures jointly 54.4% (95% CI = 25.3-72.1%) of oesophageal adenocarcinomas. Overweight and obesity explain 36.1% (95% CI = 9.1-55.1%), current and past smoking 24.2% (95% CI = 4.2-40.0%), and these exposures jointly 51.2% (95% CI = 26.3-67.8%) of stomach cardia cancers. Several population groups had a significantly higher smoking-attributable oesophageal cancer burden, including men and those consuming excessive alcohol.

CONCLUSIONS

Smoking is the leading preventable behavioural cause of oesophageal cancers and overweight/obesity of stomach cancers.

Estimating population coverage of Tackling Indigenous Smoking teams, a placed-based health intervention in Australia

OBJECTIVE

As part of the Tackling Indigenous Smoking (TIS) program, TIS teams provide Aboriginal and Torres Strait Islander-led tobacco control in their geographic area. We aimed to estimate the percentage and number of Aboriginal and Torres Strait Islander peoples living in an area serviced by a TIS team in 2018-19.

METHODS

We analysed weighted, representative data from 8,048 Aboriginal and Torres Strait Islander people aged ≥10 years from the 2018-19 National Aboriginal and Torres Strait Islander Health Survey. TIS services mapping data were used to define areas served by TIS teams. Coverage was explored in relation to remoteness, program priority groups and sociodemographic characteristics.

RESULTS

Around three-quarters (76.4%,95%CI:72.9-79.9) of the 2018-19 population aged ≥10 years lived in an area served by TIS teams (n=479,000). Coverage by TIS teams was generally similar across groups, with few exceptions.

CONCLUSIONS

The recently announced expansion to national coverage would provide access to locally tailored tobacco control to a further 148,000 Aboriginal and Torres Strait Islander peoples aged ≥10 years, including 46,000 adults who currently smoke.

IMPLICATIONS FOR PUBLIC HEALTH

Expansion to national TIS team coverage is a welcomed first step on the path to ensuring equitable access to tobacco control.

Output-orientated policy engagement: a model for advancing the use of epidemiological evidence in health policy

BACKGROUND

Use of epidemiological research in policy and practice is suboptimal, contributing to significant preventable morbidity and mortality. Barriers to the use of research evidence in policy include lack of research-policy engagement, lack of policy-relevant research, differences in policymaker and researcher practice norms, time constraints, difficulties in coordination, and divergent languages and reward systems.

APPROACH AND OUTCOMES

In order to increase policy-relevant research and research uptake, we developed the output-orientated policy engagement (OOPE) model, in Australia. It integrates a foundational approach to engagement with cycles of specific activity focused around selected research outputs. Foundational elements include measures to increase recognition and valuing of policymaker expertise, emphasis on policy uptake, policy awareness of the research group's work, regular policy engagement and policy-relevant capacity-building. Specific activities include (i) identification of an "output"-usually at draft stage-and program of work which are likely to be of interest to policymakers; (ii) initial engagement focusing on sharing "preview" evidence from this output, with an invitation to provide input into this and to advise on the broader program of work; and (iii) if there is sufficient interest, formation of a researcher-policy-maker partnership to shape and release the output, as well as inform the program of work. This cycle is repeated as the relationship continues and is deepened. As well as supporting policy-informed evidence generation and research-aware policymakers, the output-orientated model has been found to be beneficial in fostering the following: a pragmatic starting place for researchers, in often large and complex policy environments; purposeful and specific engagement, encouraging shared expectations; non-transactional engagement around common evidence needs, whereby researchers are not meeting with policymakers with the expectation of receiving funding; built-in translation; time and resource efficiency; relationship-building; mutual learning; policy-invested researchers and research-invested policy-makers; and tangible policy impacts. A case study outlines how the output-orientated approach supported researcher-policymaker collaboration to generate new evidence regarding Aboriginal and Torres Strait Islander cardiovascular disease risk and to apply this to national guidelines.

CONCLUSION

Output-orientated policy engagement provides a potentially useful pragmatic model to catalyse and support partnerships between researchers and policymakers, to increase the policy-relevance and application of epidemiological evidence.

Capacity of the 45 and Up Study to mobilise evidence-based improvements in cancer control: lung cancer case study

OBJECTIVE

Over the 15 years since the 45 and Up Study (the Study) was established, researchers have harnessed its capacity for enabling rigorous, comprehensive investigation of cancer causes, care, and outcomes. For the first time in Australia, the entire cancer-control continuum could be investigated by linking questionnaire data with cancer registry notifications, hospital records, outpatient medical services and prescription medications at scale. Here, we use lung cancer as a case study to demonstrate the Study's potential to improve cancer control.

METHOD

Narrative description.

RESULTS

Between 2006-2013, approximately 1200 participants in the Study cohort who had no prior history of cancer were diagnosed with lung cancer, allowing the generation of novel, policy- and practice-relevant evidence for tobacco control, screening, and systems of care. The Study produced evidence on the continuing impact of smoking, including that 'light smoking' (1-5 cigarettes/day) is associated with nine times the risk of lung cancer compared to never-smoking; and that 54% of lung cancers could be avoided long-term if all Australians who smoked were to quit. The Study was used to validate a lung cancer screening risk prediction tool, correctly identifying 70% of the participants with a history of smoking who developed lung cancer within a 6-year period as 'high-risk'. Potential inequities in lung cancer care were identified using the Study cohort, including suboptimal levels of radiotherapy utilisation, below benchmark levels of systemic therapy for patients with metastatic disease, and high numbers of emergency department presentations prior to diagnosis. Participants with lung cancer reported poorer quality of life than those with almost any other cancer type, and about 50% reported severe physical functioning limitations. The Study also provided the infrastructure for the first comprehensive report on lung cancer health system costs.

LESSONS LEARNT

As a statewide, population-based cohort, the Study provides reliable estimates of cancer risk, health services utilisation, and person-centred outcomes that can inform policy and practice decision making; and has provided the backbone for localising policy-relevant insights from international experience. We have found that the direct involvement of clinicians and policy makers in research design, and engagement with community networks, can yield tractable, policy-relevant, and ultimately impactful scientific insights.

The 45 and Up Study: reflecting on contributions to global evidence using case studies on cardiovascular disease and smoking

BACKGROUND/OBJECTIVE

To describe the attributes that have underscored the success of the 45 and Up Study (the Study) and demonstrate its value by reflecting on two case studies: our research on socioeconomic inequalities in cardiovascular disease; and the harms of smoking. Type of program or service: The Study is the largest study of healthy ageing in Australia, and one of the biggest in the world; it recruited 267 357 participants aged 45 years and older from NSW, Australia from 2005 to 2009. For more than 15 years, it has provided high-quality evidence on a broad range of public health related issues. We reflect on its value using two research case studies.

RESULTS

Four key attributes have enabled the success of the Study: its establishment as a collaborative resource, including early and ongoing engagement with researchers and policy and practice partners; its large scale, which makes it ideally suited to quantify associations between risk factors and health outcomes, including for high priority populations; high quality self-reported survey data; and linkage to routinely collected administrative data, including specialised data. Novel Australian findings on cardiovascular disease (CVD) and smoking illustrate how the Study has contributed to national and international evidence, informing policy and practice. Results on CVD demonstrated individual-level education-related inequalities in CVD incidence and mortality, and greater use of pharmacotherapy for secondary prevention of CVD, in people with low versus high socioeconomic status. In terms of smoking, Study data showed that current smokers have around three times the mortality of never-smokers; that even "light" smoking of <14 cigarettes per day doubles mortality; that quitting is beneficial at any age; that smoking increases the risk of multiple cancer types; and that smoking causes half of deaths in Aboriginal and Torres Strait Islander adults aged 45 years and over and more than one-third of all deaths in the population. This evidence has been used by more than 50 government and non-government organisations, including contributing to legislation, policy and national and international monitoring and reporting.

LESSONS LEARNT

The Study has fulfilled a vital role in public health research and practice in Australia, providing locally relevant data to enable research on health issues of importance, including health inequity. Through ongoing partnerships, the Study's data has contributed to international scientific evidence and been used to inform public health policy and practice. It has also been used as a focus for collaboration and capacity building.

Population-level contribution of interpersonal discrimination to psychological distress among Australian Aboriginal and Torres Strait Islander adults, and to Indigenous-non-Indigenous inequities: cross-sectional analysis of a community-controlled First Nations cohort study

BACKGROUND

International and population-specific evidence identifies elevated psychological distress prevalence among those experiencing interpersonal discrimination. We aim to quantify the potential whole-of-population contribution of interpersonal discrimination to psychological distress prevalence and Indigenous-non-Indigenous gaps in Australia.

METHODS

We did a cross-sectional analysis of data from Mayi Kuwayu: the National Study of Aboriginal and Torres Strait Islander Wellbeing. Baseline surveys were completed between June 8, 2018, and Sept 28, 2022. We analysed responses from participants who were aged 18 years or older at survey completion, whose surveys were processed between Oct 1, 2018, and May 1, 2021. Sample weights were developed on the basis of national population benchmarks. We measured everyday discrimination using an eight-item measure modified from the Everyday Discrimination Scale and classified experiences as racial discrimination if participants attributed these experiences to their Indigeneity. Psychological distress was measured using a validated, modified Kessler-5 scale. Applying logistic regression, we calculated unadjusted odds ratios (ORs), to approximate incident rate ratios (IRRs), for high or very high psychological distress in relation to everyday discrimination and everyday racial discrimination across age-gender strata. Population attributable fractions (PAFs), under the hypothetical assumption that ORs represent causal relationships, were calculated using these ORs and population-level exposure prevalence. These PAFs were used to quantify the contribution of everyday racial discrimination to psychological distress gaps between Indigenous and non-Indigenous adults.

FINDINGS

9963 survey responses were eligible for inclusion in our study, of which we analysed 9951 (99·9%); 12 were excluded due to responders identifying as a gender other than man or woman (there were too few responses from this demographic to be included as a category in stratified tables or adjusted analyses). The overall prevalence of psychological distress was 48·3% (95% CI 47·0-49·6) in those experiencing everyday discrimination compared with 25·2% (23·8-26·6) in those experiencing no everyday discrimination (OR 2·77 [95% CI 2·52-3·04]) and psychological distress prevalence was 49·0% (95% CI 47·3-50·6) in those experiencing everyday racial discrimination and 31·8% (30·6-33·1) in those experiencing no everyday racial discrimination (OR 2·06 [95% CI 1·88-2·25]. Overall, 49·3% of the total psychological distress burden among Aboriginal and Torres Strait Islander adults could be attributable to everyday discrimination (39·4-58·8% across strata) and 27·1% to everyday racial discrimination. Everyday racial discrimination could explain 47·4% of the overall gap in psychological distress between Indigenous and non-Indigenous people (40·0-60·3% across strata).

INTERPRETATION

Our findings show that interpersonal discrimination might contribute substantially to psychological distress among Aboriginal and Torres Strait Islander adults, and to inequities compared with non-Indigenous adults. Estimated PAFs include contributions from social and health disadvantage, reflecting contributions from structural racism. Although not providing strictly conclusive evidence of causality, this evidence is sufficient to indicate the psychological harm of interpersonal discrimination. Findings add weight to imperatives to combat discrimination and structural racism at its core. Urgent individual and policy action is required of non-Indigenous people and colonial structures, directed by Aboriginal and Torres Strait Islander peoples.

FUNDING

National Health and Medical Research Council of Australia, Ian Potter Foundation, Australian Research Council, US National Institutes of Health, and Sierra Foundation.

Relationship of Aboriginal family wellbeing to social and cultural determinants, Central Australia: 'Waltja tjutangku nyakunytjaku'

OBJECTIVE

The objective of this study was to apply a strength-based approach to examine the relation of cultural and social determinants to high family functioning for Aboriginal people in Central Australia.

DESIGN

Cross-sectional study involving a quantitative analysis of survey data. Prevalence rate ratios (PRs) and 95% CIs were calculated from binomial regressions, adjusted for gender and age. Qualitative data from workshops with Aboriginal leaders in Central Australia supported the interpretation of the research findings.

PARTICIPANTS

The study involved 639 Aboriginal people in Central Australia who participated in the Mayi Kuwayu Study.

RESULT

Overall, 57.9% (370/639) of participants reported high/very high family functioning, 16.9% (108/639) reported moderate and 13.3% (85/639) reported low. The adjusted prevalence of family functioning was similar across gender, age groups and household sizes. Family functioning was associated with lower family financial status (aPR=0.74, 95% CI=0.60 to 0.91) and receiving welfare (0.88, 0.77 to 1.00). Family functioning was greater with high community cohesion (2.72, 1.68 to 4.39), high individual agency in community (2.15, 1.63 to 2.85); having an Aboriginal language as a first language (1.20, 1.04 to 1.37); speaking your Aboriginal language a lot (1.37, 1.12 to 1.68); high exposure to cultural practice and knowledge (1.45, 1.28 to 1.65); and multigenerational or extended family households (1.19, 1.02 to 1.38).

CONCLUSION

High family functioning is a strength in Central Australia and is intrinsically connected with culture. Healthcare providers and programmes that build on the foundations of culture and family are an important approach to improving wellbeing.

Large-Scale Population-Based Surveys Linked to Administrative Health Databases as a Source of Data on Health Utilities in Australia

OBJECTIVES

Large-scale health surveys that contain quality-of-life instruments are a rich source of health utility data for health economic evaluations, especially when linked to routinely collected, administrative health databases. We derived health utility values for a wide range of health conditions using a large Australian cohort study linked to population-wide health databases.

METHODS

Short-Form 6-Dimension utility values were calculated for 56 094 adults, aged 47+ years, in the New South Wales 45 and Up Study who completed the Social, Economic, and Environmental Factors survey (2010-2011). Mean utilities were summarized for major health conditions identified through self-report, hospital records, primary cancer notifications, and claims for government-subsidized prescription medicines and medical services. To identify unique associations between health conditions and utilities, beta regression was performed. Utility values were analyzed by time to death using linked death records.

RESULTS

Mean Short-Form 6-Dimension utility was 0.810 (95% confidence interval [CI] 0.809-0.811), was age dependent, and was higher in men than women. Utilities for serious health conditions ranged from 0.685 (95% CI 0.652-0.718) for lung cancer to 0.800 (95% CI 0.787-0.812) for melanoma whereas disease-free respondents had a mean of 0.859 (95% CI 0.858-0.861). Most health conditions were independently associated with poorer quality of life. Utility values also declined by proximity to death where participants sampled 6 months before death had a mean score of 0.637 (95% CI 0.613-0.662).

CONCLUSIONS

Our data offer a snapshot of the health status of an older Australian population and show that record linkage can enable comprehensive ascertainment of utility values for use in health economic modeling.

Quantifying cause-related mortality in Australia, incorporating multiple causes: observed patterns, trends and practical considerations

BACKGROUND

Mortality statistics using a single underlying cause of death (UC) are key health indicators. Rising multimorbidity and chronic disease mean that deaths increasingly involve multiple conditions. However, additional causes reported on death certificates are rarely integrated into mortality indicators, partly due to complexities in data and methods. This study aimed to assess trends and patterns in cause-related mortality in Australia, integrating multiple causes (MC) of death.

METHODS

Deaths (n = 1 773 399) in Australia (2006-17) were mapped to 136 ICD-10-based groups and MC indicators applied. Age-standardized cause-related rates (deaths/100 000) based on the UC (ASRUC) were compared with rates based on any mention of the cause (ASRAM) using rate ratios (RR = ASRAM/ASRUC) and to rates based on weighting multiple contributing causes (ASRW).

RESULTS

Deaths involved on average 3.4 causes in 2017; the percentage with >4 causes increased from 20.9 (2006) to 24.4 (2017). Ischaemic heart disease (ASRUC = 73.3, ASRAM = 135.8, ASRW = 63.5), dementia (ASRUC = 51.1, ASRAM = 98.1, ASRW = 52.1) and cerebrovascular diseases (ASRUC = 39.9, ASRAM = 76.7, ASRW = 33.5) ranked as leading causes by all methods. Causes with high RR included hypertension (ASRUC = 2.2, RR = 35.5), atrial fibrillation (ASRUC = 8.0, RR = 6.5) and diabetes (ASRUC = 18.5, RR = 3.5); the corresponding ASRW were 12.5, 12.6 and 24.0, respectively. Renal failure, atrial fibrillation and hypertension ranked among the 10 leading causes by ASRAM and ASRW but not by ASRUC. Practical considerations in working with MC data are discussed.

CONCLUSIONS

Despite the similarities in leading causes under the three methods, with integration of MC several preventable diseases emerged as leading causes. MC analyses offer a richer additional perspective for population health monitoring and policy development.

Rapid macropinocytic transfer of α-synuclein to lysosomes

The nervous system spread of alpha-synuclein fibrils is thought to cause Parkinson's disease (PD) and other synucleinopathies; however, the mechanisms underlying internalization and cellular spread are enigmatic. Here, we use confocal and superresolution microscopy, subcellular fractionation, and electron microscopy (EM) of immunogold-labeled α-synuclein preformed fibrils (PFFs) to demonstrate that this form of the protein undergoes rapid internalization and is targeted directly to lysosomes in as little as 2 min. Uptake of PFFs is disrupted by macropinocytic inhibitors and circumvents classical endosomal pathways. Immunogold-labeled PFFs are seen at the highly curved inward edge of membrane ruffles, in newly formed macropinosomes, in multivesicular bodies and in lysosomes. While most fibrils remain in lysosomes, a portion is transferred to neighboring naive cells along with markers of exosomes. These data indicate that PFFs use a unique internalization mechanism as a component of cell-to-cell propagation.

Projections of smoking-related cancer mortality in Australia to 2044

BACKGROUND

While many high-income countries including Australia have successfully implemented a range of tobacco control policies, smoking remains the leading preventable cause of cancer death in Australia. We have projected Australian mortality rates for cancer types, which have been shown to have an established relationship with cigarette smoking and estimated numbers of cancer deaths attributable to smoking to 2044.

METHODS

Cancer types were grouped according to the proportion of cases currently caused by smoking: 8%-30% and >30%. For each group, an age-period- cohort model or generalised linear model with cigarette smoking exposure as a covariate was selected based on the model fit statistics and validation using observed data. The smoking-attributable fraction (SAF) was calculated for each smoking-related cancer using Australian smoking prevalence data and published relative risks.

RESULTS

Despite the decreasing mortality rates projected for the period 2015-2019 to 2040-2044 for both men and women, the overall number of smoking-related cancer deaths is estimated to increase by 28.7% for men and 35.8% for women: from 138 707 (77 839 men and 60 868 women) in 2015-2019 to 182 819 (100 153 men and 82 666 women) in 2040-2044. Over the period 2020-2044, there will be 254 583 cancer deaths (173 943 men and 80 640 women) directly attributable to smoking, with lung, larynx, oesophagus and oral (comprising lip, oral cavity and pharynx) cancers having the largest SAFs.

INTERPRETATION

Cigarette smoking will cause over 250 000 cancer deaths in Australia from 2020 to 2044. Continued efforts in tobacco control remain a public health priority, even in countries where smoking prevalence has substantially declined.

Factors related to under-treatment of secondary cardiovascular risk, including primary healthcare: Australian National Health Survey linked data analysis

OBJECTIVE

To inform national evidence gaps on cardiovascular disease (CVD) preventive medication use and factors relating to under-treatment - including primary healthcare engagement - among CVD survivors in Australia.

METHODS

Data from 884 participants with self-reported CVD from the 2014-15 National Health Survey were linked to primary care and pharmaceutical dispensing data for 2016 through the Multi-Agency Data Integration Project. Logistic regression quantified the relation of combined blood pressure- and lipid-lowering medication use to participant characteristics.

RESULTS

Overall, 94.8% had visited a general practitioner (GP) and 40.0% were on both blood pressure- and lipid-lowering medications. Medication use was least likely in: women versus men (OR=0.49[95%CI:0.37-0.65]), younger participants (e.g. 45-64y versus 65-85y: OR=0.58[0.42-0.79])and current versus never-smokers (OR=0.73[0.44-1.20]). Treatment was more likely in those with ≥9 versus ≤4 conditions (OR=2.15[1.39-3.31]), with ≥11 versus 0-2 GP visits/year (OR=2.62[1.53-4.48]) and with individual CVD risk factors (e.g. high blood pressure OR=3.13 [2.34-4.19]) versus without); the latter even accounting for GP service-use frequency.

CONCLUSIONS

Younger people, smokers, those with infrequent GP visits or without CVD risk factors were the least likely to be on medication.

IMPLICATIONS FOR PUBLIC HEALTH

Substantial under-treatment, even among those using GP services, indicates opportunities to prevent further CVD events in primary care.

Raking of data from a large Australian cohort study improves generalisability of estimates of prevalence of health and behaviour characteristics and cancer incidence

Background

Health surveys are commonly somewhat non-representative of their target population, potentially limiting the generalisability of prevalence estimates for health/behaviour characteristics and disease to the population. To reduce bias, weighting methods have been developed, though few studies have validated weighted survey estimates against generally accepted high-quality independent population benchmark estimates.

Methods

We applied post-stratification and raking methods to the Australian 45 and Up Study using Census data and compared the resulting prevalence of characteristics to accepted population benchmark estimates and separately, the incidence rates of lung, colorectal, breast and prostate cancer to whole-of-population estimates using Standardised Incidence Ratios (SIRs).

Results

The differences between 45 and Up Study and population benchmark estimates narrowed following sufficiently-informed raking, e.g. 13.6% unweighted prevalence of self-reported fair/poor overall health, compared to 17.0% after raking and 17.9% from a population benchmark estimate. Raking also improved generalisability of cancer incidence estimates. For example, unweighted 45 and Up Study versus whole-of-population SIRs were 0.700 (95%CI:0.574–0.848) for male lung cancer and 1.098 (95%CI:1.002–1.204) for prostate cancer, while estimated SIRs after sufficiently-informed raking were 0.828 (95%CI:0.684–0.998) and 1.019 (95%CI:0.926–1.121), respectively.

Conclusion

Raking may be a useful tool for improving the generalisability of exposure prevalence and disease incidence from surveys to the population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01626-5.

Opening up safely: public health system requirements for ongoing COVID-19 management based on evaluation of Australia's surveillance system performance

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) community transmission was eliminated in Australia from 1/11/2020 to 30/6/2021, allowing evaluation of surveillance system performance in detecting novel outbreaks, including against variants of concern (VoCs). This paper aims to define system requirements for coronavirus disease 2019 (COVID-19) surveillance under future transmission and response scenarios, based on surveillance system performance to date.

METHODS

This study described and evaluated surveillance systems and epidemiological characteristics of novel outbreaks based on publicly available data, and assessed surveillance system sensitivity and timeliness in outbreak detection. These findings were integrated with analysis of other critical COVID-19 public health measures to establish future COVID-19 management requirements.

RESULTS

Twenty-five epidemiologically distinct outbreaks and five distinct clusters were identified in the study period, all linked through genomic sequencing to novel introductions from international travellers. Seventy percent (21/30) were detected through community testing of people with acute respiratory illness, and 30% (9/30) through quarantine screening. On average, 2.07% of the State population was tested in the week preceding detection for those identified through community surveillance. From 17/30 with publicly available data, the average time from seeding to detection was 4.9 days. One outbreak was preceded by unexpected positive wastewater results. Twenty of the 24 outbreaks in 2021 had publicly available sequencing data, all of which identified VoCs. A surveillance strategy for future VoCs similar to that used for detecting SARS-CoV-2 would require a 100-1000-fold increase in genomic sequencing capacity compared to the study period. Other essential requirements are maintaining outbreak response capacity and developing capacity to rapidly engineer, manufacture, and distribute variant vaccines at scale.

CONCLUSIONS

Australia's surveillance systems performed well in detecting novel introduction of SARS-CoV-2 while community transmission was eliminated; introductions were infrequent and case numbers were low. Detection relied on quarantine screening and community surveillance in symptomatic members of the general population, supported by comprehensive genomic sequencing. Once vaccine coverage is maximised, future COVID-19 control should shift to detection of SARS-CoV-2 VoCs, requiring maintenance of surveillance systems and testing all international arrivals, alongside greatly increased genomic sequencing capacity. Effective government support of localised public health response mechanisms and engagement of all sectors of the community is crucial to current and future COVID-19 management.

Clearing the air: underestimation of youth smoking prevalence associated with proxy-reporting compared to youth self-report

Background

Smoking remains a leading cause of disease burden globally. Declining youth smoking prevalence is an essential feature of effective tobacco control; however, accurate data are required to assess progress. This study investigates bias in youth smoking prevalence estimates by respondent type (proxy-reported, self-report with parent present, or self-report independently) for Aboriginal and Torres Strait Islander and total populations of Australia.

Methods

Repeated cross-sectional analysis of representative Aboriginal and Torres Strait Islander Health and National Health Surveys, 2007–2019. Data were restricted to participants aged 15–17 years. Prevalence ratios (PR) and 95% Confidence Intervals (CI) for ever-smoking by respondent type were calculated using Poisson regression with robust standard errors. National youth current-smoking prevalence was estimated if all data were collected by youth self-report; estimates and trends were compared to observed estimates.

Results

Over 75% of all smoking status data were reported by proxy or with parent present. Ever-smoking prevalence among youth self-reporting independently versus proxy-reported was 1.29 (95% CI:0.96–1.73) to 1.99 (95% CI:1.39–2.85) times as high for Aboriginal and Torres Strait Islander youth, and 1.83 (95% CI:0.92–3.63) to 2.72 (95% CI:1.68–4.41) times as high for total population youth. Across surveys, predicted national current-smoking prevalence if all youth self-reported independently was generally higher than observed estimate.

Conclusions

Estimates of youth smoking prevalence are likely inaccurate and underestimated if data are collected by proxy or with parent present. Increased reliance on data reported by youth independently is crucial to improve data accuracy, including to enable accurate assessment of national prevalence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01594-w.

Aboriginal and Torres Strait Islander health checks: sociodemographic characteristics and cardiovascular risk factors

OBJECTIVE

To quantify Aboriginal and Torres Strait Islander health check claims in Australian adults in relation to sociodemographic and health characteristics, including prior cardiovascular disease (CVD) and CVD risk factors.

METHODS

The study involved analysis of baseline data (2006-2009) from the Sax Institute's 45 and Up Study, involving 1753 Aboriginal and Torres Strait Islander adults in New South Wales, Australia, linked to Medicare Benefits Schedule (MBS) hospital and death data (to December 2015). The outcome was a claim for receiving a Medicare-funded Health Assessment for Aboriginal and Torres Strait Islander People (MBS item 715) in the 2 years before December 2015. Logistic regression was used to estimate odds ratios (ORs) for receiving a health check in relation to sociodemographic and health characteristics.

RESULTS

One-third (32%) of participants received at least one Medicare-funded health check in the 2-year period. The probability of receiving a health check was higher for women than men (adjusted OR 1.47; 95% CI 1.18, 1.84), for those with lowest education than for those with highest education (OR 1.58; CI 1.11, 2.24), for those in a regional area (OR 1.56; CI 1.22, 2.01) or remote area (OR 2.38; CI 1.8, 3.16) than for those in major cities, for those with prior CVD than for those without (OR 1.80; CI 1.42, 2.27), for those with CVD risk factors than for those without (adjusted OR between 1.28 and 2.28, depending on risk factor), for those with poor self-rated health than for those with excellent self-rated health (OR 3.15; CI 1.76, 6.65) and for those with more than 10 visits to a general practitioner (GP) per year than for those with 0-2 visits (OR 33.62; CI 13.45, 84.02). Additional adjustment for number of GP visits or self-rated health substantially attenuated ORs for prior CVD and most CVD risk factors. When mutually adjusted, use of GP services and poorer self-rated health remained strongly associated with receiving a health check.

CONCLUSIONS

Aboriginal and Torres Strait Islander people with the greatest healthcare need and at highest risk of CVD were more likely to receive a health check; however, a significant proportion of those who were eligible had not received this preventive care intervention. Findings indicate that there is greater potential for the use of health checks (MBS item 715) in improving identification and management of Aboriginal and Torres Strait Islander people at high risk of CVD, potentially preventing future CVD events.

Accurate categorisation of menopausal status for research studies: a step-by-step guide and detailed algorithm considering age, self-reported menopause and factors potentially masking the occurrence of menopause

OBJECTIVE

Menopausal status impacts risk for many health outcomes. However, factors including hysterectomy without oophorectomy and Menopausal Hormone Therapy (MHT) can mask menopause, affecting reliability of self-reported menopausal status in surveys. We describe a step-by-step algorithm for classifying menopausal status using: directly self-reported menopausal status; MHT use; hysterectomy; oophorectomy; intervention timing; and attained age. We illustrate this approach using the Australian 45 and Up Study cohort (142,973 women aged ≥ 45 years).

RESULTS

We derived a detailed seven-category menopausal status, able to be further consolidated into four categories ("pre-menopause"/"peri-menopause"/"post-menopause"/"unknown") accounting for participants' ages. 48.3% of women had potentially menopause-masking interventions. Overall, 93,107 (65.1%), 9076 (6.4%), 17,930 (12.5%) and 22,860 (16.0%) women had a directly self-reported "post-menopause", "peri-menopause", "pre-menopause" and "not sure"/missing status, respectively. 61,464 women with directly self-reported "post-menopause" status were assigned a "natural menopause" detailed derived status (menopause without MHT use/hysterectomy/oophorectomy). By accounting for participants' ages, 105,817 (74.0%) women were assigned a "post-menopause" consolidated derived status, including 15,009 of 22,860 women with "not sure"/missing directly self-reported status. Conversely, 3178 of women with directly self-reported "post-menopause" status were assigned "unknown" consolidated derived status. This algorithm is likely to improve the accuracy and reliability of studies examining outcomes impacted by menopausal status.

Smokers increasingly motivated and able to quit as smoking prevalence falls: umbrella and systematic review of evidence relevant to the 'hardening hypothesis', considering transcendence of manufactured doubt

INTRODUCTION

The "hardening hypothesis" proposes that as the prevalence of smoking in a population declines, there will be a "hardening" of the remaining smoker population. This review examines the evidence regarding smokers' motivation, dependence and quitting behaviour as smoking prevalence declines, to assess whether population "hardening" (decreasing propensity to quit) or "softening" (the converse) is occurring.

METHODS

MEDLINE, PsychINFO, Scopus, Web of Science and Cochrane Library were searched to July 2019, using terms related to smoking and hardening, for reviews and large, population-based repeat cross-sectional studies. There were additional searches of reference lists and citations of key research articles. Two reviewers screened half the titles and abstracts each, and two reviewers screened full texts independently using tested criteria. Four reviewers independently and systematically extracted data from eligible publications, with one reviewer per study, checked by another reviewer.

RESULTS

Of 265 titles identified, three reviews and ten repeat cross-sectional studies were included. Reviews concluded that hardening has not occurred among the general smoking population over time. Among repeated cross-sectional studies, five examined motivation, nine examined dependence, five examined hardcore smoking, and two examined quit outcomes. All but one study found a lack of hardening. Most found softening within the smoking population, consistent across hardening indicators, definitions, countries (and tobacco control environments) and time periods examined.

CONCLUSIONS

Tobacco control reduces smoking prevalence and fosters a smoking population more amenable to evidence-based interventions. Based on the weight of the available evidence, the "hardening hypothesis" should be rejected and the reality of softening accepted.

IMPLICATIONS

This umbrella review and systematic review provides a critical consideration of evidence from psychology and other fields regarding the "hardening hypothesis" - a persistent myth undermining tobacco control. It reaches the conclusion that the sum-total of the world-wide evidence indicates either "softening" of the smoking population, or a lack of hardening. Hence, tobacco control reduces smoking prevalence and fosters a smoking population more amenable to evidence-based interventions. The review indicates that the time has come to take active steps to combat the myth of hardening and to replace it with the reality of "softening".

Observed and predicted premature mortality in Australia due to non-communicable diseases: a population-based study examining progress towards the WHO 25X25 goal

BACKGROUND

The World Health Organization's (WHO) 25X25 goal aims for a 25% relative reduction in premature death due to four non-communicable diseases (NCD4)-cancer, cardiovascular disease, chronic respiratory diseases and diabetes-by 2025 compared to 2010. This study aimed to quantify the premature mortality in the Australian population due to NCD4, quantify the variation in mortality rates by age and sex, predict the premature mortality due to NCD4 in 2025 and evaluate the progress towards the WHO 25X25 goal.

METHODS

A population-based study using cause-specific mortality data of all deaths which occurred in Australia from 2010 to 2016 and registered up to 2017, for adults aged 30-69 years, was conducted. Age-specific and age-standardised mortality rates (ASMR) and probability of death for NCD4 were calculated for each year. ASMRs in 2016 were calculated for men and women. Deaths and the probability of death in 2025 were predicted using Poisson regression based on data from 2006 to 2016. To assess the progress against the WHO 25X25 goal, the relative reduction in the probability of death from NCD4 conditions in 2025 compared to 2010 was calculated.

RESULTS

ASMRs for NCD4 decreased from 2010 to 2016, except for diabetes which increased on average by 2.5% per year. Across sociodemographic factors, ASMRs were highest in males and increased with age. The projected probability of premature death in 2025 was 7.36%, equivalent to a relative reduction of 25.16% compared to 2010 levels.

CONCLUSIONS

Premature mortality due to cancer, cardiovascular disease, respiratory diseases and diabetes declined in Australia from 2010 to 2016. This trend is consistent across age groups and by sex, and higher mortality rates were observed in males and at older ages. Nationally, if the current trends continue, we estimate that Australia will achieve a 25.16% relative reduction in premature deaths due to NCD4 in 2025 compared to 2010, signifying substantial progress towards the WHO 25X25 goal. Concerted efforts will need to continue to meet the 25X25 goal, especially in the context of the COVID-19 pandemic.

Education-related inequalities in cause-specific mortality: first estimates for Australia using individual-level linked census and mortality data

BACKGROUND

Socioeconomic inequalities in mortality are evident in all high-income countries, and ongoing monitoring is recommended using linked census-mortality data. Using such data, we provide the first estimates of education-related inequalities in cause-specific mortality in Australia, suitable for international comparisons.

METHODS

We used Australian Census (2016) linked to 13 months of Death Registrations (2016-17). We estimated relative rates (RR) and rate differences (RD, per 100 000 person-years), comparing rates in low (no qualifications) and intermediate (secondary school) with high (tertiary) education for individual causes of death (among those aged 25-84 years) and grouped according to preventability (25-74 years), separately by sex and age group, adjusting for age, using negative binomial regression.

RESULTS

Among 13.9 M people contributing 14 452 732 person-years, 84 743 deaths occurred. All-cause mortality rates among men and women aged 25-84 years with low education were 2.76 [95% confidence interval (CI): 2.61-2.91] and 2.13 (2.01-2.26) times the rates of those with high education, respectively. We observed inequalities in most causes of death in each age-sex group. Among men aged 25-44 years, relative and absolute inequalities were largest for injuries, e.g. transport accidents [RR = 10.1 (5.4-18.7), RD = 21.2 (14.5-27.9)]). Among those aged 45-64 years, inequalities were greatest for chronic diseases, e.g. lung cancer [men RR = 6.6 (4.9-8.9), RD = 57.7 (49.7-65.8)] and ischaemic heart disease [women RR = 5.8 (3.7-9.1), RD = 20.2 (15.8-24.6)], with similar patterns for people aged 65-84 years. When grouped according to preventability, inequalities were large for causes amenable to behaviour change and medical intervention for all ages and causes amenable to injury prevention among young men.

CONCLUSIONS

Australian education-related inequalities in mortality are substantial, generally higher than international estimates, and related to preventability. Findings highlight opportunities to reduce them and the potential to improve the health of the population.

Revision of the Australian guidelines to reduce health risks from drinking alcohol

Introduction

The Australian guidelines to reduce health risks from drinking alcohol were released in 2020 by the National Health and Medical Research Council. Based on the latest evidence, the guidelines provide advice on how to keep the risk of harm from alcohol low. They refer to an Australian standard drink (10 g ethanol).

Recommendations:

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Guideline 1: To reduce the risk of harm from alcohol‐related disease or injury, healthy men and women should drink no more than ten standard drinks a week and no more than four standard drinks on any one day. The less you drink, the lower your risk of harm from alcohol.

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Guideline 2: To reduce the risk of injury and other harms to health, children and people under 18 years of age should not drink alcohol.

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Guideline 3: To prevent harm from alcohol to their unborn child, women who are pregnant or planning a pregnancy should not drink alcohol. For women who are breastfeeding, not drinking alcohol is safest for their baby.

Changes as result of the guideline

The recommended limit for healthy adults changed from two standard drinks per day (effectively 14 per week) to ten per week. The new guideline states that the less you drink, the lower your risk of harm from alcohol. The recommended maximum on any one day remains four drinks (clarified from previously “per drinking occasion”). Guidance is clearer for pregnancy and breastfeeding, and for people aged less than 18 years, recommending not drinking.

Thyroid cancers potentially preventable by reducing overweight and obesity in Australia: A pooled cohort study

Thyroid cancer incidence and the prevalence of overweight and obesity are increasing, but the future thyroid cancer burden attributable to contemporary levels of overweight and obesity has not been evaluated before. We quantified this burden in Australia, and assessed whether the overweight/obesity-attributable burden differed by sex or other population subgroupings. We estimated the strength of the associations of overweight and obesity with thyroid cancer with adjusted proportional hazards models using pooled data from seven Australian cohorts (N = 367 058) with 431 thyroid cancer cases ascertained from linked national cancer registry data during a maximum 22-year follow-up. We combined these estimates with nationally representative 2017 to 2018 estimates of overweight and obesity prevalence to estimate population attributable fractions (PAFs) of future thyroid cancers attributable to overweight and obesity, accounting for competing risk of death, and compared PAFs for population subgroups. Contemporary levels of overweight and obesity explain 18.6% (95% confidence interval [CI] = 5.2%-30.2%), and obesity alone 13.7% (95% CI: 5.2%-21.4%), of the future thyroid cancer burden. The obesity-attributable thyroid cancer burden is 21.4% (95% CI: 2.8%-36.5%) for men and 10.1% (95% CI: 0.8%-18.6%) for women. Were the currently obese overweight instead, 9.9% (95% CI: 1.0%-18.1%) of thyroid cancers could be avoided. The relative overweight/obesity-attributable burden is higher for those consuming on average more than two alcoholic drinks per day (63.4%) and for those who are not married/co-habiting (33.2%). In conclusion, avoiding excess weight, especially obesity, should be a priority for thyroid cancer prevention. Further studies, with findings stratified by tumour size, may reveal the potential role of overdiagnosis in our results.

Corticosteroid Use and Risk of Herpes Zoster in a Population-Based Cohort

OBJECTIVE

To examine the relationship between corticosteroid use and herpes zoster risk.

METHODS

With data from a large cohort of adults (the 45 and Up Study) recruited between 2006 and 2009 and linked to health data sets, the effect of corticosteroid use on zoster risk was analyzed by Cox proportional hazards models, adjusting for age, sex, and other characteristics.

RESULTS

During 602,152 person-years (median, 7.36 years) of follow-up, there were 20,048 new systemic corticosteroid users and 6294 incident herpes zoster events among 94,677 participants (zoster incidence, 11.0 per 1000 person-years). Compared with nonusers, the risk of zoster was 59% higher in those using systemic corticosteroids (adjusted hazard ratio [aHR], 1.59; 95% CI, 1.48 to 1.71) and greater with higher cumulative doses: aHR of 1.32 (95% CI, 1.17 to 1.48), 1.74 (95% CI, 1.55 to 1.95), and 1.80 (95% CI, 1.61 to 2.02) for use of less than 500 mg, 500 mg to less than 1000 mg, and 1000 mg or more prednisolone equivalents, respectively (P value for trend, <.001). Compared with nonusers, zoster risk increased significantly (aHR, 6.00; 95% CI, 4.85 to 7.42) in the month after a single prescription of systemic corticosteroids and returned to levels similar to those in nonusers by the third month after dispensing (aHR, 0.91; 95% CI, 0.49 to 1.69).

CONCLUSION

Practitioners should be alert to the increased risk of zoster among patients taking systemic corticosteroids. Given the significant morbidity from zoster, particularly in older adults, these findings support judicious prescribing of corticosteroids, including using as low a dose and as short a course as possible.

Markers of chronic disease risk in a cohort of Aboriginal children: findings from the Study of Environment on Aboriginal Resilience and Child Health (SEARCH)

OBJECTIVE

This study investigated chronic disease risk markers among a cohort of Aboriginal children in New South Wales.

METHODS

Distributions of body mass index (BMI), blood lipids and haemoglobin A1c (HbA1c) among Aboriginal children aged 5-<19 years were investigated. Prevalence ratios (PR) were calculated for borderline/high total cholesterol, low-density lipoprotein (LDL) cholesterol and HbA1c, and low high-density lipoprotein (HDL) cholesterol, by age group, sex and BMI.

RESULTS

Almost half (46.8%) of the cohort, had a normal BMI and 53.3% had overweight or obesity. Prevalence of chronic disease risk markers was low, with no individuals having high total cholesterol (0.0%) and few having high LDL (3.0%) or borderline/high HbA1c (2.6%); 85.5% of the cohort had normal HDL. There was no significant variation in the prevalence of chronic disease risk markers by age group or sex. The prevalence of borderline total cholesterol was 28% higher (PR 1.28, 95%CI 1.06-1.54), and the prevalence of low HDL was double (2.00, 1.19-3.35) for participants with obesity versus normal BMI.

CONCLUSIONS

Dyslipidaemia and elevated HbA1c prevalence was low in the cohort, increasing with high BMI. Overweight and obesity were common, which increase the risk of developing chronic disease later in life. Implications for public health: Findings indicate few Aboriginal children have dyslipidaemia and hyperglycaemia, supporting screening for chronic disease risk factors from 18 years of age. Opportunities to reduce overweight and obesity among children should be considered to decrease the future risk of chronic disease.

923Quantifying multiple causes of death: Observed patterns in Australia, 2006–2017

Background

Four fifths of deaths in Australia involve multiple causes, but statistics typically use a single underlying cause of death (UC). The UC approach alone is insufficient for understanding the impact of non-underlying causes and identifying comorbid disease associations at death. Analysis of multiple causes of death (MC) is needed to measure the impact of all causes. We described MC patterns, considering cause-of-death coding and certification practices in Australia.

Methods

Using deaths registered in Australia from 2006 to 2017 (n = 1773525) coded to the International Classification of Diseases (ICD) and an extended classification (n = 136 causes) based on a World Health Organization short list, we described MCoD data by cause. Age-standardised rates based on UC and MC were compared using the standardised ratio of multiple to underlying causes (SRMU) to estimate the contribution of the cause to mortality compared to using the UC approach. Comorbidity was explored using the cause of death association indicator (CDAI) to compare the observed joint frequency of a contributory-underlying cause combined with expected frequency of the contributory cause (with any UC).

Results

On average 3.4 conditions caused each death and 24.4% of deaths had 5 plus causes. Largest SRMUs were for genitourinary diseases (8.0), blood diseases (7.8) and musculoskeletal conditions (6.7). CDAIs showed high associations between, for example, accidental alcohol and opioid poisoning, septicaemia and skin infections, and traumatic brain injury and falls.

Conclusions

MC indicators enhance measures of mortality and reassess the role of causes of death for descriptive and analytical epidemiology.

Key messages

This research demonstrates the value of MC analysis for Australian mortality data.

934Prevalence by proxy: Estimating youth smoking prevalence using nationally representative household surveys

Background

Reducing youth (15-17 years) smoking uptake is critical to tobacco control; accordingly, youth smoking prevalence is a key monitoring and evaluation outcome. Many nationally representative surveys collect youth smoking behaviour data from, or in the presence of, the youth’s parent or caregiver. We aimed to quantify the potential bias conferred by this.

Methods

We compared youth smoking prevalence when reported by parent proxy, with parent present or by private self-report, in Australian Bureau of Statistics Health Surveys. National youth current smoking prevalence if all data were collected by youth self-report was estimated.

Results

Smoking behaviour data for over 75% of youth participants in the health survey were collected by proxy or with parent present. Ever-smoking prevalence using private self-report versus report by proxy was 1.29 (95%CI:0.96-1.73) to 1.99 (1.39-2.85) times as high in Aboriginal and Torres Strait Islander youth, and 1.83 (0.92-2.63) to 2.72 (1.68-4.41) times as high in total population youth. Predicted national current smoking prevalence if all youth were to self-report alone was substantively higher than the estimated national prevalence based on actual responses, but still reveals a decline over time.

Conclusions

Youth smoking estimates drawn from data collected by proxy/with parent present are unlikely to be accurate. Increased youth self-report is crucial to ensure data accuracy to inform effective tobacco control.

Key messages

The accuracy of youth smoking data collected by proxy/with parent present should be further scrutinised before it is used to inform assessment of national prevalence and trends.

704The preventable future burden of cancer in Australia

Background

Estimates of the future burden of invasive cancer attributable to current modifiable causal exposures can guide cancer prevention.

Methods

We linked pooled data from seven Australian cohort studies (N = 367,058) to national cancer and death registries, and estimated exposure-cancer and exposure-death associations using adjusted proportional hazards models. We estimated exposure prevalence from contemporary national health surveys and calculated population attributable fractions (PAFs) and 95% confidence intervals, using advanced methods accounting for competing risk of death.

Results

Current levels of past and current smoking explain 36.1% (95%CI 33.2%-38.9%), body fatness 13.6% (10.9%-16.2%) and alcohol consumption exceeding two drinks/day 2.3% (1.0%-3.6%) of cancers causally related to these exposures, corresponding to 210,000, 81,300 and 14,800 cancers in Australia in the next 10 years, respectively. Ever smoking is the leading modifiable cause of lung (82.1%), bladder (49.8%), oesophageal (42.8%), liver (39.8%), head and neck (35.6%), and pancreatic (21.3%) cancer burden. Body fatness is the leading modifiable cause of corpus uteri (42.5%), gastric cardia (33.6%), renal cell (29.1%), thyroid (20.1%), colorectal (12.6%) and postmenopausal breast (12.6%) cancer burden. The absolute numbers of cancers in the next 10 years attributable to smoking are highest for lung cancer (114,000). The numbers of cancers attributable to body fatness and alcohol are highest for colorectal cancer (23,000 and 9,900, respectively).

Conclusions

More reliable advanced methods demonstrate large proportions and numbers of cancers are preventable by modifying behaviours.

Key messages

Ever smoking and body fatness are the leading causes of preventable future burden of causally related cancers in Australia.