Successful ageing from old to very old: a longitudinal study of 12,432 women from Australia

Objectives: We examined the development of disease and disability in a large cohort of older women, the extent to which these conditions exempt them from being classified as successful agers and different trajectories of disease, disability and longevity across women's later life. Methods: We used survey data from 12,432 participants of the 1921-26 birth cohort of the Australian Longitudinal Study of Women's Health from 1996 (age 70-75) to 2016 (age 90-95). Repeated measures latent class analysis (RMLCA) identified trajectories of the development of disease with or without disability and according to longevity. Bivariate analyses and multivariable multinomial logistic regression models were used to examine the association between participants' baseline characteristics and membership of the latent classes. Results: Over one-third of women could be considered to be successful agers when in their early 70s, few women could still be classified in this category throughout their later life or by the end of the study when they were in their 90s (~1%). RMLCA identified six trajectory groups including managed agers long survivors (9.0%) with disease but little disability, usual agers long survivors (14.9%) with disease and disability, usual agers (26.6%) and early mortality (25.7%). A small group of women having no major disease or disability well into their 80s were identified as successful agers (5.5%). A final group, missing surveys (18.3%), had a high rate of non-death attrition. Groups were differentiated by a number of social and health factors including marital status, education, smoking, body mass index, exercise and social support. Conclusions: The study shows different trajectories of disease and disability in a cohort of ageing women, over time and through to very old ages. While some women continue into very old age with no disease or disability, many more women live long with disease but little disability, remaining independent beyond their capacity to be classified as successful agers.Julie E. Byles, Md Mijanur Rahman, Emily M. Princehorn, Elizabeth G. Holliday, Lucy Leigh, Deborah Loxton, John Beard, Paul Kowal, Carol Jagge

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

First published: 30 November 2021Thyroid 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 2017-2018 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%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. This article is protected by copyright. All rights reserved.Maarit A. Laaksonen, Robert J. MacInnis, Karen Canfell, Jonathan E. Shaw, Dianna J. Magliano, Emily Banks ... et al

The future burden of head and neck cancers attributable to modifiable behaviors in Australia: a pooled cohort study

Background: Estimates of future burden of cancer attributable to current modifiable causal exposures can guide cancer prevention. We quantified future head and neck cancer burden in Australia attributable to individual and joint causal exposures, and assessed whether these burdens differ between population subgroups. Methods: We estimated the strength of the associations between exposures and head and neck cancer using adjusted proportional hazards models from pooled data from seven Australian cohorts (N ¼ 367,058) linked to national cancer and death registries and estimated exposure prevalence from the 2017 to 2018 Australian National Health Survey. We calculated population attributable fractions (PAF) with 95% confidence intervals (CI), accounting for competing risk of death, and compared PAFs for population subgroups. Results: Contemporary levels of current and former smoking contribute 30.6% (95% CI, 22.7%–37.8%), alcohol consumption exceeding two standard drinks per day 12.9% (95% CI, 7.6%– 17.9%), and these exposures jointly 38.5% (95% CI, 31.1%– 45.0%) to the future head and neck cancer burden. Alcohol-attributable burden is triple and smoking-attributable burden is double for men compared with women. Smoking-attributable burden is also at least double for those consuming more than two alcoholic drinks daily or doing less than 150 minutes of moderate or 75 minutes of vigorous activity weekly, and for those aged under 65 years, unmarried, with low or intermediate educational attainment or lower socioeconomic status, compared with their counterparts. Conclusions: Two-fifths of head and neck cancers in Australia are preventable by investment in tobacco and alcohol control. Impact: Targeting men and other identified high-burden subgroups can help to reduce head and neck cancer burden disparities.Maarit A. Laaksonen, Karen Canfell, Robert J. MacInnis, Emily Banks, Julie E. Byles, Graham G. Giles, Dianna J. Magliano, Jonathan E. Shaw, Vasant Hirani, Tiffany K. Gill, Paul Mitchell, Robert G. Cumming, Usha Salagame, and Claire M. Vajdi

The future burden of lung cancer attributable to current modifiable behaviours: a pooled study of seven Australian cohorts

Background: Knowledge of preventable disease and differences in disease burden can inform public health action to improve health and health equity. We quantified the future lung cancer burden preventable by behavioural modifications across Australia. Methods: We pooled seven Australian cohort studies (n = 367 058) and linked them to national registries to identify lung cancers and deaths. We estimated population attributable fractions and their 95% confidence intervals (CIs) for modifiable risk factors, using risk estimates from the cohort data and risk factor exposure distribution from contemporary national health surveys. Results: During the first 10-year follow-up, there were 2025 incident lung cancers and 20 349 deaths. Stopping current smoking could prevent 53.7% (95% CI, 50.0–57.2%) of lung cancers over 40 years and 18.3% (11.0–25.1%) in 10 years. The smoking-attributable burden is highest in males, those who smoke <20 cigarettes per day, are <75 years of age, unmarried, of lower educational attainment, live in remote areas or are healthy weight. Increasing physical activity and fruit consumption, if causal, could prevent 15.6% (6.9–23.4%) and 7.5% (1.3–13.3%) of the lung cancer burden, respectively. Jointly, the three behaviour modifications could prevent up to 63.0% (58.0–67.5%) of lung cancers in 40 years, and 31.2% (20.9–40.1%) or 43 300 cancers in 10 years. The preventable burden is highest among those with multiple risk factors. Conclusions: Smoking remains responsible for the highest burden of lung cancer in Australia. The uneven burden distribution distinguishes subgroups that could benefit the most from activities to control the world’s deadliest cancer.Maarit A Laaksonen, Karen Canfell, Robert MacInnis, Maria E Arriaga ... Tiffany K Gill ... Anne W Taylor ... et al

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.Maarit A. Laaksonen, Siqi Li, Karen Canfell, Robert J. MacInnis, Graham G. Giles, Emily Banks, Julie E. Byles, Dianna J. Magliano, Jonathan E. Shaw, Tiffany K. Gill, Vasant Hirani, Robert G. Cumming, Paul Mitchell, Michelle Bonello, the Australian cancer-PAF cohort consortium, Claire M. Vajdi

The Future Colorectal Cancer Burden Attributable to Modifiable Behaviors: A Pooled Cohort Study

Background: Previous estimates of the colorectal cancer (CRC) burden attributed to behaviors have not considered joint effects, competing risk, or population subgroup differences. Methods: We pooled data from seven prospective Australian cohort studies (n ¼ 367 058) and linked them to national registries to identify CRCs and deaths. We estimated the strength of the associations between behaviors and CRC risk using a parametric piecewise constant hazards model, adjusting for age, sex, study, and other behaviors. Exposure prevalence was estimated from contemporary National Health Surveys. We calculated population attributable fractions for CRC preventable by changes to current behaviors, accounting for competing risk of death and risk factor interdependence. Statistical tests were two-sided. Results: During the first 10 years of follow-up, there were 3471 incident CRCs. Overweight or obesity explained 11.1%, ever smoking explained 10.7% (current smoking 3.9%), and drinking more than two compared with two or fewer alcoholic drinks per day explained 5.8% of the CRC burden. Jointly, these factors were responsible for 24.9% (95% confidence interval [CI] ¼ 19.7% to 29.9%) of the burden, higher for men (36.7%) than women (13.2%, Pdifference < .001). The burden attributed to these factors was also higher for those born in Australia (28.7%) than elsewhere (16.8%, Pdifference ¼ .047). We observed modification of the smoking-attributable burden by alcohol consumption and educational attainment, and modification of the obesity-attributable burden by age group and birthplace. Conclusions: We produced up-to-date estimates of the future CRC burden attributed to modifiable behaviors. We revealed novel differences between men and women, and other high–CRC burden subgroups that could potentially benefit most from programs that support behavioral change and early detection.Claire M. Vajdic, Robert J. MacInnis, Karen Canfell, Peter Hull, Maria E. Arriaga, Vasant Hirani, Robert G. Cumming, Paul Mitchell, Julie E. Byles, Graham G. Giles, Emily Banks, Anne W. Taylor, Jonathan E. Shaw, Dianna J. Magliano, Julie Marker, Barbara-Ann Adelstein, Tiffany K. Gill, Maarit A. Laaksone