bluuebunny/crossref_metadata_2025 huggingface dataset:
915Inference on Causation from Examining Changes in Regression coefficients and Innovative STatistical AnaLyses (ICE CRISTAL)
Authors: Hopper John , Li Shuai , Bui Minh , Dowty James
Published: September 2021

Focus of Presentation

Causation is critical if epidemiology is to be relevant to public health. Mendelian Randomisation makes causal inference about from simply observing an association between the outcome and a genetic variable that has been conferred the title of “instrumental” because the proponents consider it satisfies some assumptions perfectly. We take this association as the starting point of a Popperian approach that tries to falsify causal hypotheses by relaxing assumptions and considering alternate models.

Findings

We developed methods to calculate test-of-fit statistics for different causal scenarios based on the joint changes in regression coefficients, using simulations and bootstrapping methods. Let Y be the outcome, X a putative cause, and G a potential instrumental variable associated with X and Y. We regress Y against X and G alone, and with X and G together. We predicted the changes to regression coefficients that should occur under three scenarios; (i) X causes Y, (ii) there is a factor C associated with Y, X and G. and (ii) Y causes X. We compared goodness-of-fit statistics across scenarios, and for combinations of scenarios (given multiple causal processes might co-exist). We present findings from application to data on body mass index and DNA methylation and compare with Mendelian Randomisation analyses.

Conclusions/Implications

Robust inference can be made but the sample sizes and strengths of associations need to be substantive.

Key messages

Causation is a fundamentally important issue that should, and can, be addressed by trying to disprove it, rather than by finding evidence for it.
888Discriminating between risk discriminators: OPERA, AUC, and polygenic variance
Authors: Hopper John , Dowty James
Published: September 2021

Focus of Presentation

Epidemiological risk estimates are often adjusted for age (and, if necessary, sex) by design or analysis, and for other factors. Consequently, risk estimates do not pertain to the crude risk factor, but to its population residual after adjusting for age, sex and other covariates. For disease risk, the change in Odds PER Adjusted standard deviation (OPERA) estimates the risk gradient on an appropriate scale; log(OPERA) is the natural measure to compare estimates.

Findings

Under a multiplicative risk model for a normally distributed (adjusted) risk factor, log(OPERA) = the difference in mean between cases and controls. The area under the receiver operating curve (AUC) = □(log(OPERA)/√2), where □ is the standard normal cumulative distribution function. The risk discrimination from combining risk factors can be predicted from their OPERAs. The polygenic standard deviation estimated from pedigree data = log(OPERA). The OPERA for knowing all familial risk factors can be calculated.

Conclusions/Implications

We present examples from the breast cancer literature where the wrong conclusions can be made by not using the OPERA concept. We give examples of the value of OPERA estimates in predicting the risk discrimination of their combination and demonstrate why the better one predicts the disease the harder it is to predict it better.

Key messages

OPERA overcomes problems about interpreting risk factors, and combinations of risk factors, in a way not apparent using changes in AUC. OPERA also puts an upper bound on the role of genetic factors in explaining differences in risk across the population.
890The prevalence and risk factors for Coxiella burnetii on commercial dairy goat farms in Australia
Authors: Hou Kangwei , Firestone Simon , Wiethoelter Anke , Stenos John , Lignereux Louis , Clark Nicolas , Aleri Joshua , Magalhães Ricardo , Stevenson Mark
Published: September 2021

Background

Despite the potentially important role that intensively managed dairy goats play in the spread of Q fever, the prevalence of Coxiella burnetii among dairy goat herds in Australia is largely unknown. The aim of this cross-sectional study was to estimate the prevalence of coxiellosis-positive dairy goat herds in Australia and to identify risk factors associated with coxiellosis positivity.

Methods

Owners or managers of commercial dairy goat herds were contacted and asked to complete a questionnaire about risk factors for coxiellosis and to provide a bulk tank milk (BTM) sample. BTM samples were tested using an enzyme-linked immunosorbent assay (ELISA) and real-time quantitative polymerase chain reaction (RT-PCR) targeting the Com1 and IS1111 sections of the C. burnetii genome. Questionnaire responses from coxiellosis positive and coxiellosis negative herds were compared using frequency cross-tabulations and multivariable logistic regression.

Results

Herd managers from 49 of the 61 commercial dairy goat herds in Australia took part in the study. Of this group, three BTM samples were found to be both ELISA and RT-PCR positive. Two BTM samples were ELISA positive but RT-PCR negative. There were 10 (95% CI 4.4 to 22) C. burnetii positive herds per 100 herds at risk.

Conclusions

The prevalence of coxiellosis among commercial dairy goat farms in Australia is relatively low.

Key messages

The Australian dairy goat industry should focus on biosecurity measures and risk management plans to reduce the probability of C. burnetii introduction.
128Study data within systematic reviews of intensive care interventions analysed as a cluster randomized trial
Authors: Hurley James
Published: September 2021

Focus of Presentation

Cluster randomized trials (CRT) can address infectious disease research questions at the whole-of-population level, such as herd protection and herd peril effects, that cannot be answered within randomized controlled trials. For adequate power, ideally, a CRT will have at least 40 clusters.

Findings

Studies of decontamination (using either chlorhexidine or topical antibiotics) to prevent ICU-acquired infections among adult patients requiring prolonged mechanical ventilation (MV) have been summarized in > 15 systematic reviews. Of 83 studies of topical antibiotics, 69 had concurrent control (CC) versus non-concurrent control (NCC; n = 14) design (Figure below; solid symbols are intervention group patients). The mean ICU pneumonia incidence for topical antibiotic study CC control groups (34.5%; 95% CI, 29.1-40.4) is higher versus a literature benchmark (26.1%; 23.3%-29.1%), and versus NCC control groups (29.9%; 21.4-40.4) and versus chlorhexidine study CC control groups (25.5%; 19.6 – 32.5; n = 17).

Conclusions/Implications

Benchmarking the event rates among control groups versus the event rate among non-intervention studies for MV patients provide a measure of the contextual effect of the intervention. Differing intervention effects for studies with CC versus NCC design implicates herd effects.

Key messages

Systematic reviews of interventions that include studies with CC versus NCC design provide a natural experiment of contextual effects where their study otherwise would be difficult or, for adverse herd effects, unethical.
1414Hormone replacement therapy, oral contraceptives and stroke risk
Authors: Johansson Therese , Johansson Docent Åsa , Karlsson Torgny , Ek Docent Weronica E , Fowler Philip
Published: September 2021

Background

Millions of women use exogenous hormones as hormone replacement therapy (HRT) or oral contraceptives (OC). Still, time-dependent and long-term consequences of exogenous hormones on cerebrovascular health remains unclear.

Methods

We examined the effects of HRT and OC usage on stroke risk in 256,661 women from UK Biobank, born between 1939 and 1970. Outcomes included any type of stroke, ischemic stroke (IS), intracerebral hemorrhage (IH), and subarachnoid hemorrhage (SH). Exposures were analyzed as time-dependent variables in Cox regression models. Results are expressed as hazard ratios (HR) with 95% confidence intervals.

Results

During first year of exposure, HRT usage was associated with higher hazard rates of any stroke (HR = 2.12[1.66-2.70]), IS (HR = 1.93[1.04-3.56]) and SH (HR = 2.14[1.23-3.72]) compared to non-usage, which remained significant only for any stroke during remaining years of exposure. Similarly, we observed an increased hazard of any stroke during first year of OC exposure (HR = 2.29[1.34-3.92]), while the hazards were found to be comparable during remaining years of use (HR = 1.03[0.92-1.17]). Conversely, women who previously had been exposed to OC, had a lower hazard rate of any stroke later in life, (HR = 0.88[0.82-0.94]).

Conclusions

Our findings suggest that HRT and OC use cause immediate changes in hemostatic balance, therefore increasing the short-term stroke risk. However, long-term effects of OC use during reproductive years might improve cerebrovascular health and prevent stroke events later in life.

Key messages

HRT usage increase the risk of stroke, both short-term and with longer use, while the increased stroke risk might be limited to the first year of OC use.
896Quantifying cause-related mortality incorporating multiple causes: challenges and opportunities
Authors: Joshy Grace , Eynstone-Hinkins James , Moran Lauren , Balogun Saliu , Bishop Karen , Moreno-Betancur Margarita
Published: September 2021

Key contact person

Dr Grace Joshy, Fellow, Research School of Population Health, Australian National University.

Focus and outcomes for participants

Mortality statistics are typically based on a single underlying cause of death (UCoD), derived from multiple conditions on the death certificate, and have provided critical evidence for policy and practice for over a century. There have been radical shifts in patterns of death in the past couple of decades; deaths in older ages are increasingly from chronic and degenerative diseases. The relevance of assuming that a single disease is causing the death is diminishing, especially with an aging population structure and increasing life expectancy. This symposium will enable participants to understand the complexities associated with mortality reporting/coding, strengths and limitations of available statistical methods for using multiple causes of death (MCoD) and the importance of quantifying mortality incorporating MCoD.

Rationale for the symposium, including for its inclusion in the Congress

The use of a single UCoD rather than MCoD means that vast amounts of potentially useful data are largely ignored, which is likely to bias mortality estimates (including under- and over-reporting of the importance of certain causes of death). Despite global recognition of the urgent need to better integrate data on MCoD into mortality statistics, use of these data are challenging and limited. Complexities arise from the way mortality information is reported on death certificates and coded to form mortality collections; limited understanding of available statistical methods also adds to the complexity.

International Classification of Diseases 10th Revision (ICD-10) has been translated into 43 languages and it is being used by over 100 countries to report mortality data, a primary indicator of health status. The 2018 release of the 11th revision of the International Classification of Diseases, enriching data on multiple parameters including comorbidity, confers further urgency and a unique opportunity to optimise the use of MCoD in mortality reporting.

The World Congress of Epidemiology 2020 will provide a unique platform for wider discussions on the challenges and opportunities for using MCoD data. The symposium will provide a deeper understanding and enhanced the use of MCoD data. The speakers are engaged in cutting-edge NHMRC-funded research on mortality incorporating MCoD and development of novel statistical methods.

Presentation program

The symposium will feature presentations from six speakers.

Names of presenters

James Eynstone-Hinkins, Lauren Moran, Saliu Balogun, Karen Bishop, Margarita Moreno-Betancur, Grace Joshy
1385Hesitancy for Adult Vaccination -A New Paradigm for Research in India
Authors: Kalra Nikhita , Kalra Tanisha , Mishra Suruchi , Basu Saurav , Bhatnagar Nidhi
Published: September 2021

Background

Adult immunization has recently emerged as an area of emphasis in research and policy. Increasing life expectancy, outbreaks like COVID-19, and the endemic nature of diseases like dengue, malaria have underscored its importance. Therefore, this study was carried out with the aim to assess hesitancy and factors influencing the uptake of vaccines in adults.

Methods

An online cross-sectional study was conducted among adults (age more than 20 years). Data collection was done by convenience sampling in January 2021. Information on awareness and perceptions regarding adult vaccination and immunization status of participants was collected. Data analysis was done using SPSS version 21.

Results

A total of 461 adults responded to the survey. Among those who had never received any vaccine in adulthood (n = 158), the reasons were lack of recommendation by healthcare providers (38.6%), lack of knowledge of vaccines (15.8%) and fear of adverse effects following vaccination (7.6%). Hesitancy for vaccines among those who were informed by healthcare workers was as follows: shingles (97.8%), human papillomavirus (92.1%), pneumococcal (91.1%), influenza (79.7%), varicella (79.4%) and tetanus (57.6%).

Conclusions

Reduced vaccine uptake due to vaccine hesitancy in adulthood is a major health concern. Hesitancy was highest for the shingles vaccine and least for the tetanus vaccine.

Key messages

Coverage of adult vaccination can be improved by formulating national guidelines and encouraging healthcare providers to raise awareness. In-depth qualitative studies are needed to understand the perception of adults towards vaccination.
1295School age outcomes in IVF-conceived children compared with controls: a population linkage study
Authors: Kennedy Amber , Vollenhoven Beverley , Hiscock Richard , Stern Catharyn , Walker Susan , Cheong Jeanie , Quach Jon , Hastie Roxanne , Wilkinson David , McBain John , Gurrin Lyle , MacLachlan Vivien , Agresta Franca , Baohm Susan , Tong Stephen , Lindquist Anthea
Published: September 2021

Background

There is interest in longer term outcomes in IVF-conceived offspring compared with those conceived naturally. So far, the findings have been conflicting. The Australian Early Developmental Consensus (AEDC) assesses children in their first year of primary school across five domains.

Methods

To compare school entry outcomes in IVF-conceived children with naturally conceived controls, we undertook a statewide data linkage study, with perinatal data (2005-2014) linked to data from IVF providers in Victoria and the AEDC. Our approach to analysis included: complete case analysis, multiple imputation of missing data, consideration of clustering (siblings) and inverse probability weighted modeling to adjust for covariates. Our primary outcome was an AEDC score indicative of developmental vulnerability in two or more domains. We adjusted for confounders: child’s age at assessment, sex, highest level of maternal education, maternal age, parity, SEIFA (Socio-Economic Indexes for Areas) quintile, language background other than English, and Aboriginal and Torres Strait Islander (ATSI) status.

Results

The linked dataset comprised 163,418 children, including 4,441 IVF-conceived children. The IVF-conceived population had older, more highly educated mothers who lived in more affluent areas and were less likely to be from non-English speaking backgrounds or identify as ATSI. IVF-conceived children were less likely to be developmentally vulnerable, in both unadjusted (RR 0.59, 95%CI:0.52-0.67, p < 0.001) and adjusted analyses (aRR 0.72, 95%CI:0.58-0.88, p < 0.001).

Conclusions

IVF-conceived were less likely to be developmentally vulnerable in their first year of schooling, compared with peers conceived naturally.
624Integrating human behaviour models with epidemiology to frame complex health problems
Authors: Khan Rabia
Published: September 2021

Focus of Presentation

Health problems are complex due to multiple interactions whose outcomes are not easily predicted with traditional epidemiology methods. The problems themselves require careful evaluation. Predictive models of human behaviour are potentially powerful tools to frame health problems, especially if the models can link the attributes and behaviour of individuals with the dynamics of the social and environmental systems within which they operate. We explore this potential by proposing a framework combining two modelling approaches — social network analysis (SNA) and agent-based modelling (ABM) - with epidemiological methods. We then apply this framework to understand why measles vaccination rates are decreasing across the world.

Findings

These techniques allowed us to understand the etiologic implications of heterogeneity within the population, social interaction, and environmental influences simultaneously, and to explore mechanistic interactions, feedback loops, and reciprocity between exposures and outcomes. This approach allowed us to frame complex social factors of health and disease in a holistic manner.

Conclusions/Implications

The proposed framework allows investigators to analyse complex health problems in a holistic manner. However, both SNA and ABM, and other modelling tools, are still too compartmentalised in application, despite the strong methodological and conceptual parallels between their uses in different disciplines.

Key messages

A fully integrated approach is needed to understanding complex health problems, which combines modelling approaches and the disciplinary insights of epidemiology and public health.
1499Health behaviours as risk factors of COVID-19 incidence in South Korea
Authors: Kim Jeehyun , Yoo Daesung , Hong Kwan , Yum Sujin , Gómez Raquel Elizabeth Gómez , Chun Byung Chul
Published: September 2021

Background

Personal health behaviours, which rely on community characteristics, could affect individual vulnerability on disease infection. Due to insufficient study to examine health behaviours as risk factors of COVID-19 infection, we conducted municipal level spatial analysis to investigate association between health behaviours and COVID-19 incidence.

Methods

We extracted cumulative COVID-19 incidence data from January 20th 2020 to February 25th 2021, health behaviours, health condition, socio-economic factors, and covariates in municipal level from publicly available dataset. We chose variables, which were standardized, considering multicollinearity (VIF<10). Further, we employed bayesian hierarchical negative binomial model with intrinsic conditional autoregressive (iCAR) and Besag, York and Mollié (BYM) model, and used deviance information criterion (DIC) for final model selection.

Results

The mean cumulative COVID-19 incidence per 10,000 population among 229 municipality was 13.73 (Standard deviation=11.43). iCAR model (DIC=2,825.3) outperformed BYM model (DIC=14,009.4). The results of iCAR model highlighted that incidence was associated with dental hygiene practice (incidence risk ratios [IRR]=0.92, 95% Credible Interval [CI]=0.85–1.00), whether tried to be thin (IRR=1.10, 95% CI = 1.00–1.20), proportion of medical personnel (IRR=1.09, 95% CI = 1.01–1.17), and volume of public transportation (IRR=1.19, 95% CI = 1.05–1.35), even after adjusting for various confounding factors.

Conclusions

Municipality with lower cumulative incidence was likely to have more people who practiced to keep dental hygiene and less people who tried to be thin.

Key messages

Municipal level spatial analysis resulted that health behaviours were associated with COVID-19 incidence in South Korea.
1354Delivery channels and socioeconomic inequalities in coverage of RMNCH interventions: analysis across 36 LMICs
Authors: Leventhal Daniel , Crochemore-Silva Inácio , Vidaletti Luis , Armenta-Paulino Nancy , Barros Aluísio
Published: September 2021

Background

Socioeconomic inequalities in the coverage of reproductive, maternal, neonatal, and child health (RMNCH) interventions have been frequently described in global reports, but little is known about how inequalities vary across indicators in low- and middle-income countries (LMICs).

Methods

In this cross-sectional study, we identified publicly available national surveys from LMICs. We identified the most recent survey from the period 2010–19 for 36 countries containing data for our preselected set of 18 RMNCH interventions. Twenty-one countries also had information on two common malaria interventions. We classified interventions into four groups according to their predominant delivery channels: health facility-based, community-based, environmental, and culturally driven. We estimated absolute inequalities using the slope index of inequality (SII) and relative inequalities using the concentration index (CIX).

Results

We observed higher coverage levels among wealthier households than poorer households for most interventions in most countries, except for two breastfeeding indicators showing higher coverage for poor households than wealthy households. Environmental interventions were the most unequal, particularly use of clean fuels. Primarily health facility-based interventions—e.g. institutional childbirth—also usually had pro-rich patterns. By comparison, primarily community-based interventions, including those against malaria, were more equitably distributed.

Conclusions

Community-based interventions are usually more equitably distributed than health facility-based or environmental interventions. Policymakers need to learn from community delivery channels to promote more equitable access to all RMNCH interventions.

Key messages

The delivery channels framework is useful for designing equitable health policies and programmes, which must adapt the successes of community-based interventions to all RMNCH interventions.
227The use of cross-sectional series as a source of evidence for policymaker decision in Brazil
Authors: Rocha Hermano Alexandre Lima , Correia Luciano Lima , Rocha Dra Sabrina Gabriele Maia Oliveira , Leite Álvaro Jorge Madeiro , Machado Márcia Maria Tavares , Campos Jocileide Sales , Silva Anamaria Cavalcante e
Published: September 2021

Background

To verify the effectiveness of public policies, two or more cross-sectional studies can be carried out in series. The objective of this work is to present the maternal and child health research of Ceará (PESMIC), Brazil, a series of cross-sectional studies carried out in a partnership between the university and the local government.

Methods

PESMIC is a series of cross-sectional studies with constant methodology, a sample obtained in multiple stages, with systematic and clusters sampling, state-wide representative, which visits 8000 households in 1987, 1990, 1994, 2001, 2007 and 2017. Around 300 variables are collected, in three different questionnaires, for the home, mothers, and children.

Results

PESMIC demonstrated over 30 years the improvement of several indicators such as the drop in infant mortality from 120 to 10 per thousand, the reduction of child malnutrition from 26.8% to 8.6%, the increase in infant breastfeeding for six months from 3% to 99%, the increase in maternal literacy from 58% to 97%.

Conclusions

Over 30 years, PESMIC presented results that allowed the evaluation of public policies and the occurrence of epidemiological transitions that occurred at the population level. The use of oral rehydration serum applied by community health workers, both unprecedented in Brazil when they started in Ceará, had their effectiveness demonstrated by PESMIC and were expanded to the rest of the country soon afterward. We conclude that the transversal series are studies that can help guide decision making by public health managers.

Key messages

The use of cross-sectional series can be a feasible alternative for the formation of evidence to aid decision-making

The use of the PESMIC transversal series in Ceará helps Brazil in making important decisions such as the expansion of the community health workers program
823Suicide of welfare and care support workers: a retrospective mortality study in Australia 2001-2016
Authors: Maheen Humaira
Published: September 2021

Background

Emerging evidence suggests that people working in the welfare and health care industry have poorer mental health than other occupational groups; however, there has been little examination of suicide among this group. In this study, we examine suicide rates amongst welfare and care support workers and compare them to rates among human service workers, and all other occupations in Australia.

Methods

We used data from the National Coroners Information System (NCIS) to obtain records of death due to intentional self-harm between the years 2001 to 2016. We calculated age-standardised suicide rates and incident rate ratios to compare the suicide rates across different occupational groups.

Results

The age-standardised suicide rate of males is the highest amongst welfare and carers (24.1 per 100,000). After adjusting for age and year of death, we found that men working as welfare workers and carers have a significantly higher suicide rate than men working in other occupations (IRR 1.43, CI 1.2-1.7). Furthermore, male human service workers have a slightly lower rate of suicide than those working in other occupations (IRR 0.73: CI 0.66-0.82). The finding was similarly noted in female suicide deaths, however, the higher suicide rate in female welfare workers was not statistically significant (IRR 1.12 CI 0.9-1.39).

Conclusion

The suicide rates of welfare and care-related occupations are as high as occupations which are identified as at-risk occupations for male suicide in Australia.

Key message

There is a need for targeted programs to improve the suicide health literacy among welfare and care support workers.
1519Integrated Measles and Meningitis Vaccination Campaign in Nigeria: Experience of the Federal Capital Territory, Nigeria
Authors: Momoh Jenny , Zakari Furera
Published: September 2021

Introduction

The Nigeria government, supported by its development partners conducted several vaccination campaigns involving various antigens across the country in 2019. Majority of the states in the North including the Federal Capital Territory (FCT) implemented the Integrated Measles and Men A vaccination campaign (IVC) which itself was an innovation given that both campaigns were initially planned as stand-alone campaigns. The integration of these campaigns came with additional planning, new implementation strategies and challenges. This paper aims to highlight the key drivers of FCT’s performance in achieving greater than 90% vaccination coverage for both antigens and the challenges of the integrated campaign in FCT.

Methods

A baseline review of previous campaign reports, micro plans and tally sheet data was conducted to identify challenges of previous SIAs in FCT, best practices and lessons learnt. A preliminary analysis of available data revealed a shortfall in resources early enough in the planning phase. Notably, was a shortfall of about 300 vaccination teams for the implementation of the Measles vaccination campaign (as a standalone campaign) as well as shortfall in cold chain equipment and logistic funds. We leveraged on the thrice weekly technical coordination meetings to review these challenges to seek ways to mitigate them.

Result

Strategic efforts to address the identified gaps led to the state sponsoring an additional 354 vaccination teams to support implementation by leveraging on the SOML funds. Staggering the campaign was key to ensuring adequacy of CCEOPs to address the increase in the number required due to the integration. The additional state sponsored team vaccinated 121777 and 123588 children who otherwise would have been missed with the Measles antigen with the Men A antigen respectively.

Conclusion

Strategic resolution of identified challenges was pivotal to FCT’s performance of greater than 90% vaccination coverages for both antigens.

Key words

Measles, Meningitis A, Integrated, Vaccination, Campaign
1363Just a flu? Comparing COVID-19 and influenza mortality
Authors: Muscatello David , McIntyre Peter
Published: September 2021

Background

Benchmarks are needed for assessing the severity of the COVID-19 pandemic. However, comparisons can be misleading unless marked differences in age-specific mortality and differences in population age structure are considered.

Methods

Using COVID-19 death rates for New York City as at 2 June 2020, we used indirect age standardization to estimate standardized mortality ratios (SMR) for the first winter waves of the 1918 and 2009 influenza pandemics and the severe 2017-2018 influenza season in the United States (US). Data were obtained from published statistics.

Results

After adjusting for age, New York City’s death rate during the 1918 winter influenza pandemic wave was 6.7 times higher overall compared with the first wave of COVID-19 in 2020. New York City's first wave COVID-19 death rate was an estimated 59 times higher than that of the 2009 US influenza pandemic, and 14 times higher than that of the severe 2017-2018 influenza season. In < 45 year-olds, the 1918 influenza death rate was 42 times higher than COVID-19 in 2020. In ≥ 65 year-olds, compared with the 2009 pandemic, the COVID-19 death rate was 320 times higher, while in children it was one half.

Conclusions

The 1918 pandemic was more deadly than COVID-19, which was, in turn, far more deadly than both the 2009 influenza pandemic and severe seasonal influenza. Age-specific mortality differences should be considered in decisions on COVID-19 vaccination strategies.

Key messages

Fundamental epidemiological methods remain valuable for modern epidemic risk assessment. COVID-19 is not just a ‘flu’.
1333Economic impact of salt-reduction policies in Japan, 2019–2028: a Markov model simulation analysis
Authors: Nishi Nobuo , Kato Hiroki , Ikeda Nayu
Published: September 2021

Background

The economic impact of nutritional policies has been rarely evaluated in Japan. We aimed to assess costs and benefits of salt-reduction policies for cardiovascular disease prevention.

Methods

We conducted a cost-benefit analysis using a Markov cohort simulation model over the period 2019 to 2028. We compared two salt-reduction policies—a national media campaign to promote healthy eating and physical activity (Policy A), and voluntary reformulation by the food industry to reduce salt added in processed food (Policy B). We used epidemiological data in Japan from national surveys and a global database, and estimates from previous meta-analyses on the changes in cardiovascular incidence and mortality associated with salt reduction. We applied a costing method in a previous study in England. We estimated benefits as a decrease in medical costs associated with cardiovascular diseases and costs as the sum of monitoring costs, policy costs, and subsidies.

Results

The estimated net benefits were 66.6 billion yen for Policy A and 353.5 billion yen for Policy B, and the latter was dominant. However, Policy A became dominant when the annual subsidy for Policy B exceeded 43.7 billion yen.

Conclusions

We employed a Markov cohort simulation by partially applying Japanese data to evaluate salt-reduction policies. In future research, it is necessary to collect data on salt reduction estimates and policy costs in Japan.

Key messages

As salt-reduction policies, voluntary food reformulation will be more beneficial than the media campaign as far as the annual subsidy does not exceed one-eighth of the benefit.
1167Disease Burden and Universal Health Coverage Monitoring
Authors: Okamoto Shohei , Shimmmei Keita , Okamura Tomonori
Published: September 2021

Background

Achieving universal health coverage (UHC) is a target of the Sustainable Development Goals, and the monitoring of its progress is of use to clarify what to be enhanced for better health. While the WHO and the World Bank Group jointly developed a scale with the above purpose (WHO/WB index: Hogan et al., 2018), it fails to reflect the fact that different needs to health coverages may exist depending on a stage of epidemiological transition.

Methods

To consider potential differences in health coverage needs depending on the stage of the epidemiological transition, we reformulated the index by incorporating weight as the proportion of age-adjusted mortality rate among monitored domains (i.e. reproductive, maternal, new-born and child health, infectious disease, non-communicable diseases [NCD]), of which data collected from the WHO Global Health Observatory. Additionally, we utilised indicators of policy achievements on NCD by the WHO’s Noncommunicable Diseases Progress Monitor 2015.

Results

The UHC progress monitored by the WHO/WB index had a mean of 61.83 (%) while it declined by about 4% point on average when NCD indicators were replaced. Furthermore, the UHC progresses evaluated with weights calculated from disease burden decreased by about 10% point for both measures, suggesting that some countries may not provide demanded health coverages.

Conclusion

The UHC progress decreased when disease burden for each country was taken into consideration. This indicates the necessity to assess the UHC progressby reflecting disease structure of each country, not by an identical scale for all nations.

Key messages

The monitoring of universal health coverage is required to reflect disease structure of each country.
940Physical frailty and the onset of depressive symptom in older Japanese women
Authors: Sasai Hiroyuki , Kojima Narumi , Osuka Yosuke , Kim Hunkyung
Published: September 2021

Background

The co-occurrence of physical frailty and depressive symptoms is highly prevalent in late life. However, their causal direction remains unclear. This study examined whether frailty and its components (slowness, weakness, exhaustion, low activity, and weight loss) predict the onset of depressive symptoms among older Japanese women.

Methods

In a two-year cohort study conducted in a metropolitan area of Tokyo, we collected baseline data in October 2017 and follow-up data in September 2019. Participants were community-dwelling older Japanese women, aged 65 to 80 years without any neurological diseases or depressive symptoms. Logistic regression analyses were applied to estimate odds ratios (OR) of the onset of depressive symptoms (15-item Geriatric Depression Scale [GDS] score ≥ 6) across the baseline frailty status or its components classified by the Japanese version of Cardiovascular Health Study criteria.

Results

Of the 477 women analysed (275 robust and 202 prefrail/frail). 6 (2.2%) robust and 16 (7.9%) prefrail or frail women developed depressive symptoms. After being adjusted for various covariates including baseline GDS score, the OR of the depressive symptom onset was 3.04 (95% confidence interval [CI]: 0.99, 10.47) in the prefrail or frail women. Among the five frailty components, slowness (OR: 7.55, 95%CI: 1.11, 48.98) and exhaustion (OR: 5.00, 95%CI: 1.60, 16.13) were independently associated with the onset of depressive symptoms.

Conclusions

Physical frailty status, particularly slowness and exhaustion, predict future depressive symptoms in older women.

Key messages

Early detection and intervention targeting physical frailty may help prevent depressive symptoms in later life.
289Birthweight and risks of adult-onset diabetes in women who are and are not overweight
Authors: Shawon Shajedur Rahman , Yang TienYu Owen , Floud Sarah , Green Jane , Reeves Gill , Beral Dame Valerie
Published: September 2021

Background

Higher adult body mass index (BMI) increases diabetes risk, whereas, paradoxically, lower birthweight is associated with higher risks of adult-onset diabetes. Increased diabetes risks associated with low birthweight might be due to increased risks among those who become overweight or obese as adults but evidence on risks among those of normal BMI is limited.

Methods

In the Million Women Study, 413,516 women without prior diabetes, at mean age 60(SD5) years, reported their birthweight, and current height and weight. Birthweight and BMI at age 60 years were validated against recorded values at similar ages. Participants were followed for diabetes by electronic linkage to national hospital admissions records. Cox regression yielded multivariable-adjusted relative risks (RRs) for diabetes, overall and subdivided simultaneously by categories of birthweight and adult BMI.

Results

During 15(SD3) years follow-up, 24,528 women had hospital admissions with diabetes, first recorded at average age 70(SD6) years. Adult-onset diabetes risks increased strongly with increasing adult BMI (RR per 5 kg/m2 increase: 2.03, 95% CI 2.01-2.06). Compared to those with birthweight 3.0-3.4 kg, RRs of diabetes for birthweight <2.5 kg and ≥4.0 kg were 1.35(1.30-1.38) and 0.73(0.70-0.75), respectively. The association between low birthweight and increased diabetes risk was strongly evident among women who were of normal BMI, overweight and obese (p < 0.0001 for each).

Conclusions

At every level of adult adiposity, there were strong inverse associations between birthweight and adult-onset diabetes risk.

Key messages

While adult adiposity increases diabetes risk, there is a strong and independent increase in diabetes risk with decreasing birthweight.
1298Associations of DMT therapies with COVID-19 severity in multiple sclerosis
Authors: Simpson-Yap Steve , Brouwer Edward De , Kalincik Tomas , Rijke Nick , Hillert Jan , Walton Clare , Edan Gilles , Spelman Tim , Geyes Lotte , Parciak Tina , Gautrais Clément , Lazovski Nikola , Pirmani Ashkan , Ardeshirdavani Amin , Forsberg Lars , Glaser Anna , McBurney Robert , Schmidt Hollie , Bergmann Arnfin , Braune Stefan , Stahmann Alexander , Middleton Rodden , Salter Amber , Fox Robert , van der Walt Anneke , Butzkueven Helmut , Rojas Juan , van der Mei Ingrid , Nag Nupur , Ivanov Rumen , Olival Guilherme Sciascia do , Dias Alice Estavo , Magyari Melinda , Brum Doralina Guimarães , Mendes Maria Fernandes , Alonso Ricardo , Nicholas Richard , Bauer Johana , Chertcoff Anibal , Zabalza Ana , Arrambide Georgina , Fidao Alexander , Comi Giancarlo , Peeters Liesbet
Published: September 2021

Background

People with multiple sclerosis (MS) are a vulnerable group for severe COVID-19, particularly those taking immunosuppressive disease-modifying therapies (DMTs). We examined the characteristics of COVID-19 severity in an international sample of people with MS.

Methods

Data from 12 data-sources in 28 countries were aggregated (sources could include patients from 1-12 countries). Demographic (age, sex), clinical (MS phenotype, disability), and DMT (untreated, alemtuzumab, cladribine, dimethyl-fumarate, glatiramer-acetate, interferon, natalizumab, ocrelizumab, rituximab, siponimod, other) covariates were queried, alongside COVID-19 hospitalisation, admission to ICU, requiring artificial ventilation, and death. Characteristics of outcomes were assessed in patients with suspected/confirmed COVID-19 using multilevel mixed-effects logistic regression, adjusted for age, sex, MS phenotype, and EDSS.

Results

657 (28.1%) with suspected and 1,683 (61.9%) with confirmed COVID-19 were analysed. Among suspected+confirmed/confirmed-only COVID-19, 20.9%/26.9% were hospitalised, 5.4%/7.2% were admitted to ICU, 4.1%/5.4% required artificial ventilation, and 3.2%/3.9% died. Older age, progressive MS-phenotype, and higher disability were associated with worse COVID-19 outcomes. Compared to dimethyl-fumarate, ocrelizumab and rituximab were associated with hospitalisation (aOR=1.56,95%CI=1.01-2.41; aOR=2.43,95%CI=1.48-4.02) and ICU admission (aOR=2.30,95%CI=0.98-5.39; aOR=3.93,95%CI=1.56-9.89), though only rituximab was associated with higher risk of artificial ventilation (aOR=4.00,95%CI=1.54-10.39). Importantly, associations persisted on restriction to confirmed COVID-19 cases. No associations were observed between DMTs and death.

Conclusions

Despite the cross-sectional design of this study, the internal and external consistency of these results with prior studies suggests their use may be a risk factor for more severe COVID-19.

Key messages

Anti-CD20 DMTs may be associated with worse COVID-19 severity amongst people with multiple sclerosis.
1203Predictors of treatment and survival in hepatocellular carcinoma patients: A Bayesian parametric survival analysis
Authors: Taye Belaynew , Clark Paul , Hartel Gunter , Powell Elizabeth , Valery Patricia
Published: September 2021

Background

Culturally and linguistically diverse communities face several challenges to receiving screening and curative treatment of hepatocellular carcinoma (HCC). We reported the predictors of receipt of treatment and survival in a cohort of patients diagnosed with HCC in Southeast Queensland.

Methods

Data from 1651 HCC patients (147 migrants) followed between January 1, 2007, and December 31, 2016 were analyzed using chi-square statistic to test for the association between socio-economic variables and receipt of treatment. Bayesian Weibull Accelerated Failure Time regression was used to identify predictors of time to death, and we reported time ratios.

Results

Receipt of surgical resection for HCC was associated with non-metropolitan residence (P=0.02), non-English language (P<0.001), country of origin (P<0.001), and hepatitis B virus etiology (P<0.001). The median survival time after HCC diagnosis was 9.0 months (interquartile range 2.0‒24.0). The strongest predictors of survival were undifferentiated tumor at presentation (time ratio (TR)=0.30, 95% credible interval (CrI) 0.23‒0.39), age ≥70 years (TR = 0.42, 95%CrI 0.34‒0.53), living in a remote area (TR = 0.67, 95%CrI 0.55‒0.80), and presence of ≥ 1 comorbidity (TR = 0.69 95%CrI 0.54‒0.90).

Conclusions

Improving access to HCC surveillance and uptake of timely curative treatment for persons living in remote areas and having socioeconomic disadvantage may help patients present to clinic with early stage tumor and provide better survival.

Key messages

Remoteness of residence is associated with late presentation, low rate of receipt of treatment and predicts survival of patients with HCC.
794Bisphosphonate use and risk of ovarian cancer, a nested case-control study using national health data
Authors: Tuesley Karen , Webb Penelope , Protani Melinda , Spilsbury Katrina , Pearson Sallie-Anne , Coory Michael D , Donovan Peter , Stewart Louise M , Pandeya Nirmala , Jordan Susan
Published: September 2021

Background

Epithelial ovarian cancer (EOC) is the eighth most common cancer in women, has a five-year survival of ∼45%, and very few established modifiable risk factors. Some evidence suggests that bisphosphonates could have chemopreventive benefits, but few epidemiological studies have investigated the association between bisphosphonate use and incidence of EOC.

Methods

We conducted a nested case-control study using linked administrative data. We identified 9,367 women over 50 years diagnosed with EOC (cases) from 2004 to 2013, and for each case identified five controls from the Australian Medicare Enrolment database matched by age, state, area of residence, and area-level socioeconomic disadvantage. We assessed the associations between bisphosphonate use using dispensed prescription data (ever use, duration and dose) and EOC (overall, by histotype), adjusting for comorbidities and MHT use. We conducted sensitivity analyses in women with complete ascertainment of dispensing claims and for residents of one Australian state that had linked with data linked to hospital procedures, including oophorectomy.

Results

Our analyses show an inverse association between bisphosphonate use and risk of EOC overall (OR = 0.81, 95%CI:0.75-0.88), and for endometrioid (OR = 0.51, 95%CI:0.33-0.79) and serous (OR = 0.84, 95%CI:0.75-0.93) histotypes. There was some evidence that higher dose and duration were associated with a greater reduction in risk. Results from sensitivity analyses were not appreciably different.

Conclusions

Bisphosphonate use was associated with lower risk of EOC, suggesting bisphosphonates may reduce risk of ovarian cancer development.

Key messages

Bisphosphonates may protect against development of serous and endometrioid ovarian cancers.
566Ear infection trajectories and academic, behavioural and quality of life outcomes: A population-based longitudinal study
Authors: Wang Jing , Quach Jon , Sung Valerie , Carew Peter , Wake Melissa
Published: September 2021

Background

Middle ear infection is a common disease in childhood. Outcomes might vary by its patterns and persistence over time. We aimed to investigate 1) typical trajectories of ear infections throughout childhood and 2) their associations with child outcomes.

Methods

Design & Participants: Two parallel cohorts assessed biennially from 2004 to 2014 spanning ages 0-1 to 10-11 years (B cohort, n = 3721) and ages 4-5 to 14-15 years (K cohort, n = 3489) in the Longitudinal Study of Australian Children. Ear infection: Parent-reported ongoing ear infections (B: waves 1-6; K: waves 1, 2, 4, 5). Outcomes (wave 6): National academic standardized test, teacher-reported learning, parent and teacher-reported behaviour and self-reported quality of life. Analysis: Latent class models identified ear infection trajectories. Linear regression quantified associations between trajectories and outcomes.

Results

Four probability trajectories of ear infection emerged in both cohorts: “consistently low” (B 86.2%, K 87.0%), “moderate to low” (5.5%, 9.7%), “low to moderate” (7.0%, 1.5%), and “consistently high” (1.4%, 1.8%). In K cohort, the “consistently high” group had the worst outcomes (effect sizes 0.2-0.8 SDs), with effect sizes largest for psychosocial and language outcomes. “Moderate to low” and “low to moderate” groups showed no to marginal academic associations, but behaviour and quality of life were 0.2-0.3 SDs poorer than the “consistently low” group. Similar but attenuated associations were seen in B cohort.

Conclusions

Sizable adverse outcomes followed the consistently high trajectory, suggesting cumulative rather than age-dependent burden. Additional information about comorbidities, predictors and objective presence of ear infections could inform causal relationships.

Key messages

Parent-reported ear infections follow four childhood trajectories (consistently low, moderate to low, low to moderate, consistently high). Sizable adverse outcomes follow the consistently high trajectory.
1230Should multiple imputation be stratified by exposure group when estimating causal effects via outcome regression?
Authors: Zhang Jiaxin , Ghazaleh Dashti S. , Carlin John B. , Lee Katherine J. , Moreno-Betancur Margarita
Published: September 2021

Background

Outcome regression remains widely applied for estimating causal effects in observational studies, in which causal inference is conceptualised as emulating a randomized controlled trial (RCT). Multiple imputation (MI) is a commonly used method for handling missing data, but while in RCTs it has been shown that MI should be conducted by treatment group to reduce bias, whether imputation should be conducted by exposure group in observational studies has not been studied.

Methods

We conducted a simulation study to evaluate the performance of seven methods for handling missing data: Complete-case analysis (CCA), MI of main effect, MI with interactions (between exposure and: outcome, a strong confounder, outcome and a strong confounder, all incomplete), and MI conducted by exposure group. We simulated data based on an example from the Victorian Adolescent Health Cohort Study. Three exposure prevalences and seven outcome generation models were considered, the latter ranging from no interaction to strong-positive or negative exposure-confounder interaction. Various missingness scenarios were examined: with incomplete outcome only or also incomplete confounders, and three levels of complexity regarding the missingness mechanism.

Results

For all scenarios, MI by exposure led to the least bias, followed by MI approaches that included exposure-confounder interactions.

Conclusions

If MI is adopted in outcome regression, we recommend conducting MI by exposure group and, when not feasible, including exposure-confounder interactions in the imputation model.

Key messages

Similar to RCTs, MI should be conducted by exposure group when estimating average causal effects using outcome regression in observational studies.