Self-reported oral health status, edentulism and all-cause mortality risk in 12 809 Australian older adults: a prospective cohort study

OBJECTIVE

To investigate the association between oral health status and all-cause mortality in older adults using prospective cohort study design.

SETTING AND PARTICIPANTS

In total, 12 809 adults aged ≥70 years (54.3% females) were participants of the ASPREE Longitudinal Study of Older Persons (ALSOP).

METHODS

Participants self-reported the presence of natural teeth and oral health status. The association of self-reported oral health, edentulism and the integrative measure of the two with all-cause mortality were explored using the Cox-regression models adjusted for age, gender, socio-economic status, health-related behaviours, weight status, aspirin and polypharmacy. Hazard ratios (HRs) and 95% confidence intervals (CIs) were reported.

RESULTS

In total, 22.2% of participants reported edentulism and 13.8% had fair/poor oral health. After adjustment for confounders, risk of all-cause mortality was higher among those with edentulism (vs. no edentulism) HR (95% CI) 1.43 (1.18, 1.73); and those with edentulism and reporting poor/fair oral health HR (95% CI) 1.69 (1.02, 2.82), or with no edentulism but reporting poor/fair oral health HR (95% CI) 1.46 (1.19-1.80) vs. no edentulism and reporting good/very good/excellent oral health. No association was observed between self-reported oral health alone and all-cause mortality.

CONCLUSIONS

The risk of all-cause mortality was 69% higher among older adults reporting both edentulism and poor/fair oral health compared with those with teeth and more favourable self-reported oral health. © 2023 Australian Dental Association.

Compliance-Adjusted Estimates of Aspirin Effects Among Older Persons in the ASPREE Randomized Trial

The Aspirin in Reducing Events in the Elderly (ASPREE) Trial recruited 19,114 participants across Australia and the United States during 2010-2014. Participants were randomized to receive either 100 mg of aspirin daily or matching placebo, with disability-free survival as the primary outcome. During a median 4.7 years of follow-up, 37% of participants in the aspirin group permanently ceased taking their study medication and 10% commenced open-label aspirin use. In the placebo group, 35% and 11% ceased using study medication and commenced open-label aspirin use, respectively. In order to estimate compliance-adjusted effects of aspirin, we applied rank-preserving structural failure time models. The results for disability-free survival and most secondary endpoints were similar in intention-to-treat and compliance-adjusted analyses. For major hemorrhage, cancer mortality, and all-cause mortality, compliance-adjusted effects of aspirin indicated greater risks than were seen in intention-to-treat analyses. These findings were robust in a range of sensitivity analyses. In accordance with the original trial analyses, compliance-adjusted results showed an absence of benefit with aspirin for primary prevention in older people, along with an elevated risk of clinically significant bleeding.

Correlates of Meal Skipping in Community Dwelling Older Adults: A Cross-Sectional Study

In this cross-sectional analysis of 10,071 community dwelling adults aged ≥70 years, we examined factors associated with meal skipping (self-reported) using multivariable logistic regression. Prevalence of meal skipping in this study was 19.5%. The adjusted odds (aOR [95%CI]) of meal skipping were lower in those 85+ years (vs. 70-74.9 years, 0.56 [0.45-0.70]), and in those in regional areas (vs. urban area, 0.81 [0.72-0.92]). Higher odds of meal skipping were observed for those living alone (vs. living with someone, 1.84 [1.64-2.05]), current smokers (vs. non-smokers, 2.07 [1.54-2.80]), consumers of high amounts of alcohol (vs. abstainers 1.93 [1.35-2.75]), those with poor oral health (vs. excellent oral health, 1.71 [1.07 -2.73]) diabetes (vs. not 1.26 [1.06-1.50]), or frailty (vs. not, 1.63 [1.09-2.43]). This study identified socio-demographic, social, behavioural and biomedical correlates of meal skipping in later life, which may assist in targeting interventions to address meal skipping.

Out-of-hospital cardiac arrest in elderly individuals

Background

Out-of-hospital cardiac arrest (OHCA) is associated with poor outcome, particularly in elderly people. Due to the shift in global demographics towards an ageing population, understanding risk factors for OHCA is essential for the development of primary prevention strategies. Thus, we aimed to identify predictors for OHCA in a large, community-dwelling cohort of elderly individuals.

Methods

We analyzed data from 11,156 participants enrolled in a randomized, placebo-controlled primary prevention trial, investigating the effect of low-dose aspirin in individuals aged 70 years or above. At baseline all participants had no prior cardiovascular disease events, dementia or major physical disability. OHCA events occurring within 5 years were identified by probabilistic data-linkage with a state-wide out-of-hospital cardiac arrest registry. Possible predictors included age, sex, anthropometric measures, conventional cardiovascular risk factors, renal function and frailty. To evaluate the association with OHCA, we performed univariable and multivariable Cox regression analyses. In exploratory analyses we also evaluated the effect of low-dose aspirin on OHCA events.

Results

In the cohort 54.7% were female and median age was 74.1 years (Interquartile Range [IQR] 71.8–77.7). During a median follow up time of 4.7 years (IQR 3.4–6.0) we recorded 67 OHCA events with presumed cardiac cause. The incidence rate was 1.07 per 1,000 person-years (95% Confidence-Interval [CI] 0.80–1.40). The mortality rate following OHCA was 91.2% (n=62). Univariable Cox regression analyses identified age, sex, weight, abdominal circumference, serum creatinine, diabetes, arterial hypertension, intake of antihypertensive medication and pre-frailty as predictors for the outcome. In multivariable Cox regression analyses we identified age (Hazard Ratio [HR] 1.06, CI 1.00–1.13), female sex (HR 0.49, CI 0.26–0.94) and pre-frailty (HR 1.92, CI 1.03–3.58) to be independent predictors (Table). In exploratory analyses there was no effect of low-dose aspirin on OHCA (HR 1.52, CI 0.87–2.70).

Conclusion

In a large, contemporary cohort of healthy, elderly individuals we describe a significant incidence of OHCA events associated with a very high mortality. We identified age, sex and pre-frailty, but interestingly not conventional cardiovascular risk factors as independent predictors of OHCA. We could not show a benefit of low-dose aspirin treatment, although the number of events was small. Our findings emphasize the importance of preventive strategies for pre-frailty in elderly individuals.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The ASPREE study was primarily funded by the National Institute of Aging and National Cancer Institute at the National Institutes of Health (grant number U01AG029824), the Australian National Health & Medical Research Council (grants 334047 & 1127060), Monash University (Australia) and the Victorian Cancer Agency (Australia). Multivariable Cox regression analyses

After Action Review of the 2019 measles outbreak in Clark County, Washington, U.S.A

Issue

Clark County experienced a measles outbreak that challenged public health authorities. Description of the practice: We conducted a formal After Action Review with state and local health officials, school officials, and others to identify lessons for public health practitioners facing future outbreaks.

Results

Following the early identification of measles in a child who had recently arrived from Ukraine, active surveillance identified 71 confirmed cases, most in unvaccinated persons under 18 years of age. 4,138 contacts were traced and public health personnel made daily monitoring calls to 816. 53 potential exposure sites in healthcare facilities, schools and other public places were identified and communicated to the public. As a social distancing measure, unvaccinated students, teachers, and staff were excluded from schools in which exposure had occurred. Ascertaining susceptibility status was challenging. The national anti-vaccination sentiment and a parallel outbreak in a New York religious community created challenges in representing community risk while avoiding stigmatization of a community in which the first reported case was identified. Rather than respond to every false claim on social media, the health department developed talking points about emerging issues and engaged the community in dialogue.

Lessons

Responding to the measles outbreak required innovative approaches to surveillance and contact tracing, social distancing (school exclusions), and emergency risk communication. The response required extensive coordinated efforts of the county and state health departments, school systems, and many other organizations. Mutual aid enabled an influx of resources but managing the surge of responders proved challenging.

Key messages

Public health emergencies require effective emergency management practices. Carefully conducted After Action Reviews of health emergencies can help public health practitioners identify challenges and innovative practices.

P4557Factors associated with treatment and control of hypertension in a healthy elderly population free of cardiovascular disease: a cross-sectional study

Introduction

Despite readily available treatments, control of high blood pressure (BP) in the ageing population remains suboptimal. Gaps in understanding the management of high BP amongst the elderly exist, as most studies have been in predominantly middle-aged populations.

Purpose

We explored pharmacological BP lowering treatment and control among elderly hypertensive participants free from overt cardiovascular disease (CVD), and identified factors related to both “untreated” and “treated but uncontrolled” high BP.

Methods

We analyzed baseline data from 19,114 individuals aged ≥65 years enrolled from Australia and the US in the ASPirin in Reducing Events in the Elderly (ASPREE) study. Hypertension was defined as an average systolic/diastolic BP ≥140/90 mmHg and/or use of any BP-lowering medication. `Controlled hypertensives” were those receiving BP-lowering medication and with BP <140/90 mmHg. Descriptive analyses were used to summarize hypertension control rates; logistic regression was used to investigate relationships with treatment and BP control.

Results

Overall, 74% (14,213/19,114) of participants were hypertensive, and of these 29% (4,151/14,213) were untreated. Among those treated, 47% (4,732/10,062) had BP <140/90 mmHg. Participants who were untreated were more likely to be men, have higher educational status, and be in good physical health, and less likely to have significant comorbidities. The factors related to “treated but uncontrolled” hypertension included older age, being men, Black race (versus White), using BP lowering monotherapy and residing in Australia (versus US) (Figure 1).

Conclusion(s)

There were high levels of “untreated” and “treated but uncontrolled” BP, in an otherwise healthy elderly population, suggesting that opportunities for better BP control exist through targeting intervention to high-risk individuals.

Acknowledgement/Funding

National Institute on Aging and the National Cancer Institute at NIH; NHMRC Australia, Monash University, Victorian Cancer Agency (Australia)

P6362Impact of the 2017 AHA/ACC hypertension guideline on hypertension prevalence and cardiovascular risk factors in a healthy older cohort

Background

The 2017 American Heart Association (AHA)/American College of Cardiology (ACC) hypertension guideline recommends a target blood pressure (BP) of <130/80 mmHg regardless of age, which is lower than previously recommended BP goals.

Purpose

We aimed to determine how much the updated classification for high BP would increase the overall prevalence of “hypertension” in an otherwise healthy elderly population. Additionally, we explored the cardiovascular disease (CVD) risk factor distribution in those newly classified “hypertensives” to determine whether the increased prevalence of hypertension was accompanied by an increase in other modifiable CVD risk factors.

Methods

We used baseline data from 19,114 participants (16,703 in Australia and 2,411 in the USA) aged ≥65 years who were enrolled in the ASPirin in Reducing Events in the Elderly (ASPREE) study between 2010 and 2014. Participants were classified as having hypertension using either: (a) pre-2017 thresholds (SBP ≥140 mmHg or mean DBP ≥90 mmHg and/or on anti-hypertensive) or (b) 2017 AHA/ACC guidelines (SBP ≥130 mmHg or DBP ≥80 mmHg and/or on anti-hypertensive). We assessed the presence of cardiovascular disease risk factors such as diabetes, hypercholesterolemia, smoking, obesity, reduced renal function among these hypertensive participants and also estimated their predicted risk over 10 years.

Results

Based on pre-2017 thresholds, 74% of the participants met the criteria for hypertension. Hypertension prevalence increased to 87% when the more stringent 2017 guideline was applied. 29% of this subset of newly classified hypertensive participants did not have any other identifiable traditional CVD risk factors. Further, a significantly lower 10-year predicted cardiovascular risk (22% versus 26%, p<0.001) among those newly classified hypertensive participants was observed in relation to those having hypertension based on pre-2017 guideline (Figure 1).

Figure 1. 10-year predicted CVD risk among hyoertensive and newly classified hypertensive ASPREE participants by presence of CVD risk factor

Conclusion

As expected, the prevalence of hypertension increased among the healthy elderly when applying the new AHA-2017 guideline; however, the increased prevalence occurs despite lack of an accompanying increase in additional CVD risk factors or predicted 10-year risk. Our findings suggest an individualized approach is needed in evaluating high BP among the healthy elderly.

Acknowledgement/Funding

National Institute on Aging and the National Cancer Institute at NIH; NHMRC Australia, Monash University, Victorian Cancer Agency (Australia)

Efficient Fusion at Neutral pH by Human Immunodeficiency Virus gp41 Trimers Containing the Fusion Peptide and Transmembrane Domains

Human immunodeficiency virus (HIV) is membrane-enveloped, and an initial infection step is joining/fusion of viral and cell membranes. This step is catalyzed by gp41, which is a single-pass integral viral membrane protein. The protein contains an ∼170-residue ectodomain located outside the virus that is important for fusion and includes the fusion peptide (FP), N-helix, loop, C-helix, and viral membrane-proximal external region (MPER). The virion initially has noncovalent complexes between three gp41 ectodomains and three gp120 proteins. A gp120 contains ∼500 residues and functions to identify target T-cells and macrophages via binding to specific protein receptors of the target cell membrane. gp120 moves away from the gp41 ectodomain, and the ectodomain is thought to bind to the target cell membrane and mediate membrane fusion. The secondary and tertiary structures of the ectodomain are different in the initial complex with gp120 and the final state without gp120. There is not yet imaging of gp41 during fusion, so the temporal relationship between the gp41 and membrane structures is not known. This study describes biophysical and functional characterization of large gp41 constructs that include the ectodomain and transmembrane domain (TM). Significant fusion is observed of both neutral and anionic vesicles at neutral pH, which reflects the expected conditions of HIV/cell fusion. Fusion is enhanced by the FP, which in HIV/cell fusion likely contacts the host membrane, and the MPER and TM, which respectively interfacially contact and traverse the HIV membrane. Initial contact with vesicles is made by protein trimers that are in a native oligomeric state that reflects the initial complex with gp120 and also is commonly observed for the ectodomain without gp120. Circular dichroism data support helical structure for the N-helix, C-helix, and MPER and nonhelical structure for the FP and loop. Distributions of monomer, trimer, and hexamer states are observed by size-exclusion chromatography (SEC), with dependences on solubilizing detergent and construct. These SEC and other data are integrated into a refined working model of HIV/cell fusion that includes dissociation of the ectodomain into gp41 monomers followed by folding into hairpins that appose the two membranes, and subsequent fusion catalysis by trimers and hexamers of hairpins. The monomer and oligomer gp41 states may therefore satisfy dual requirements for HIV entry of membrane apposition and fusion.

Baseline characteristics of participants in the Kerala Diabetes Prevention Program: a cluster randomized controlled trial of lifestyle intervention in Asian Indians

AIMS

To describe the baseline characteristics of participants in the Kerala Diabetes Prevention Program.

METHODS

The Kerala Diabetes Prevention Program is a cluster randomized controlled trial of lifestyle intervention for prevention of Type 2 diabetes mellitus in India. Participants in the study were those aged 30-60 years who had an Indian Diabetes Risk Score ≥ 60 and who were without Type 2 diabetes on oral glucose tolerance test. Data on demographic, lifestyle, clinical and biochemical characteristics were collected using standardized tools.

RESULTS

A total of 2586 individuals were screened with the Indian Diabetes Risk Score, of these 1529 people (59.1%) had a score ≥ 60, of whom 1209 (79.1%) underwent an oral glucose tolerance test. A total of 202 individuals (16.7%) had undiagnosed Type 2 diabetes and were excluded, and the remaining 1007 individuals were enrolled in the trial (control arm, n = 507; intervention arm, n = 500). The mean participant age was 46.0 ± 7.5 years, and 47.2% were women. The mean Indian Diabetes Risk Score was 67.1 ± 8.4. More than two-thirds (69.0%) had prediabetes and 31.0% had normal glucose tolerance. The prevalence of cardiometabolic risk factors was high, including current tobacco use (34.4% in men), current alcohol use (39.3% in men), no leisure time exercise (98.0%), no daily intake of fruit and vegetables (78.7%), family history of diabetes (47.9%), overweight or obesity (68.5%), hypertension (22.3%) and dyslipidemia (85.4%).

CONCLUSIONS

The Kerala Diabetes Prevention Program recruited participants using a diabetes risk score. A large proportion of the participants had prediabetes and there were high rates of cardiometabolic risk factors. The trial will evaluate the effectiveness of lifestyle intervention in a population selected on the basis of a diabetes risk score.

Cardiovascular risk outcome and program evaluation of a cluster randomised controlled trial of a community-based, lay peer led program for people with diabetes

Background

The 2013 Global Burden of Disease Study demonstrated the increasing burden of diabetes and the challenge it poses to the health systems of all countries. The chronic and complex nature of diabetes requires active self-management by patients in addition to clinical management in order to achieve optimal glycaemic control and appropriate use of available clinical services. This study is an evaluation of a “real world” peer support program aimed at improving the control and management of type 2 diabetes (T2DM) in Australia.

Methods

The trial used a randomised cluster design with a peer support intervention and routine care control arms and 12-month follow up. Participants in both arms received a standardised session of self-management education at baseline. The intervention program comprised monthly community-based group meetings over 12 months led by trained peer supporters and active encouragement to use primary health care and other community resources and supports related to diabetes. Clinical, behavioural and other measures were collected at baseline, 6 and 12 months. The primary outcome was the predicted 5 year cardiovascular disease risk using the United Kingdom Prospective Diabetes Study (UKPDS) Risk Equation at 12 months. Secondary outcomes included clinical measures, quality of life, measures of support, psychosocial functioning and lifestyle measures.

Results

Eleven of 12 planned groups were successfully implemented in the intervention arm. Both the usual care and the intervention arms demonstrated a small reduction in 5 year UKPDS risk and the mean values for biochemical and anthropometric outcomes were close to target at 12 months. There were some small positive changes in self-management behaviours.

Conclusions

The positive changes in self-management behaviours among intervention participants were not sufficient to reduce cardiovascular risk, possibly because approximately half of the study participants already had quite well controlled T2DM at baseline. Future research needs to address how to enhance community based programs so that they reach and benefit those most in need of resources and supports to improve metabolic control and associated clinical outcomes.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000469213. Registered 16 June 2009.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3538-3) contains supplementary material, which is available to authorized users.

A Torque-Sensitive Tactile Array for Robotics

We introduce a new tactile sensor and show its advantages for robotic applications. The tactile array elements are composed of magnetic dipoles (in an elastic medium) whose position and orientation are detected by magnetoresistive sensors. We show that, unlike the existing tactile sensor designs, this device is sensitive to torque as well as to normal and tangential forces. We demonstrate experimentally the fabrication, sensitivity, and repeatability of the tactile elements.

The role of BRAF mutations in primary melanoma growth rate and survival

BACKGROUND

The clinical behaviour and prognosis of primary melanomas harbouring BRAF mutations is not fully understood.

OBJECTIVES

To investigate the effect of mutation status on primary melanoma growth rate and melanoma-specific survival (MSS).

METHODS

A prospective cohort of 196 patients with stage I-III primary cutaneous melanoma were followed for a median of 92 months, pre-dating the institution of BRAF inhibitor therapy. Clinicopathological variables were correlated with mutation status and hazard ratios (HRs) estimated for MSS.

RESULTS

Of 196 tumours, 77 (39.2%) were BRAF V600E, 10 (5.1%) BRAF V600K and 33 (16.8%) were NRAS mutant. BRAF V600E mutant melanomas were associated with favourable clinical characteristics and tended to be slower growing compared with BRAF V600K, NRAS mutant or BRAF/NRAS wild-type tumours (0.12 mm per month, 0.61 mm per month, 0.36 mm per month and 0.23 mm per month, respectively; P = 0.05). There were 39 melanoma deaths, and BRAF mutant melanomas were associated with poorer MSS in stage I-III disease [HR 2.60, 95% confidence interval (CI) 1.20-5.63; P = 0.02] and stage I-II disease (HR 3.39, 95% CI 1.12-10.22; P = 0.03) after adjusting for other prognostic variables. Considered separately, BRAF V600E mutant melanomas were strongly associated with MSS independently of thickness and nodal status (HR 3.89, 95% CI 1.67-9.09; P < 0.01) but BRAF V600K mutant tumours were not (HR 1.19, 95% CI 0.36-3.92; P = 0.77).

CONCLUSIONS

The presence of a BRAF mutation does not necessarily 'drive' more rapid tumour growth but is associated with poorer MSS in patients with early-stage disease.

Gastrocsoleus recession techniques

Lengthening of the conjoined tendon of the gastrocnemius aponeurosis and soleus fascia is frequently used in the treatment of equinus deformities in children and adults. The Vulpius procedure as described in most orthopaedic texts is a division of the conjoined tendon in the shape of an inverted V. However, transverse division was also described by Vulpius and Stoffel, and has been reported in some clinical studies.

We studied the anatomy and biomechanics of transverse division of the conjoined tendon in 12 human cadavers (24 legs). Transverse division of the conjoined tendon resulted in predictable, controlled lengthening of the gastrocsoleus muscle-tendon unit. The lengthening achieved was dependent both on the level of the cut in the conjoined tendon and division of the midline raphé. Division at a proximal level resulted in a mean lengthening of 15.2 mm (sd 2.0, (12 to 19), which increased to 17.1 mm (sd 1.8, (14 to 20) after division of the midline raphé. Division at a distal level resulted in a mean lengthening of 21.0 mm (sd 2.0, (18 to 25), which increased to 26.4 mm (sd 1.4, (24 to 29) after division of the raphé. These differences were significant (p < 0.001).

Cite this article: Bone Joint J 2014; 96-B:778–82.

Thromboembolism in lung cancer - an area of urgent unmet need

INTRODUCTION

Thromboembolism is common in lung cancer. Current thromboprophylaxis guidelines lack specific recommendations for appropriate strategies in this high thrombotic risk patient cohort. We profiled lung cancer patients receiving anti-cancer therapy. Thromboembolism incidence and thromboembolism-related mortality rates are reported and we explored patient, disease, and treatment-related risk factors associated with higher thrombotic rates.

METHODS

Retrospective review of lung cancer patients referred to a Comprehensive Cancer Centre between 01/07/2011 and 30/06/2012 for anti-cancer therapy. Data were collected from medical, pharmacy, pathology and diagnostic imaging electronic records.

RESULTS

After a median follow up of 10 months (range: 0.03-32 months), 24/222 patients (10.8%) had developed radiologically confirmed thromboembolism; 131 events per 1000 person-years (95%CI 87-195). Thromboembolism occurred equally in patients with non-small cell and small cell lung cancer (10.8% and 10.5% respectively), and more frequently among patients with adenocarcinoma compared to squamous cell carcinoma (14.7% and 5.3% respectively). Chemotherapy-treated patients experienced thromboembolism more often than patients who did not receive chemotherapy (HR 5.7 95%CI 2.2-14.8). Radiotherapy was also associated with more frequent thromboembolism (HR 5.2 95%CI 2.0-13.2). New lung cancer diagnosis, presence of metastatic disease, second primary malignancy and Charlson Index ≥ 5 were also associated with higher rates of thromboembolism. Importantly, pharmacological thromboprophylaxis (P-TP) was not routinely or systematically prescribed for ambulant lung cancer patients during any treatment phase, at this institution. The majority (83%) of thromboembolic events occurred in the ambulatory care setting.

CONCLUSION

Morbidity and mortality from thromboembolism occurs frequently in lung cancer. Thromboprophylaxis guidelines should be developed for the ambulatory care setting.

Most individuals with treated blood pressures above target receive only one or two antihypertensive drug classes

BACKGROUND

A significant proportion of individuals taking antihypertensive therapies fail to achieve blood pressures <140/90 mmHg. In order to develop strategies for improved treatment of blood pressure, we examined the association of blood pressure control with antihypertensive therapies and clinical and lifestyle factors in a cohort of adults at increased cardiovascular risk.

METHODS

A cross-sectional study of 3994 adults from Melbourne and Shepparton, Australia enrolled in the SCReening Evaluation of the Evolution of New Heart Failure (SCREEN-HF) study. Inclusion criteria were age ≥60 years with one or more of self-reported ischaemic or other heart disease, atrial fibrillation, cerebrovascular disease, renal impairment or treatment for hypertension or diabetes for ≥2 years. Exclusion criteria were known heart failure or cardiac abnormality on echocardiography or other imaging. The main outcome measures were the proportion of participants receiving antihypertensive therapy with blood pressures ≥140/90 mmHg and the association of blood pressure control with antihypertensive therapies and clinical and lifestyle factors.

RESULTS

Of 3623 participants (1975 men and 1648 women) receiving antihypertensive therapy, 1867 (52%) had blood pressures ≥140/90 mmHg. Of these 1867 participants, 1483 (79%) were receiving only one or two antihypertensive drug classes. Blood pressures ≥140/90 mmHg were associated with increased age, male sex, waist circumference and log amino-terminal-pro-B-type natriuretic peptide levels.

CONCLUSIONS

Most individuals with treated blood pressures above target receive only one or two antihypertensive drug classes. Prescribing additional antihypertensive drug classes and lifestyle modification may improve blood pressure control in this population of individuals at increased cardiovascular risk.

Doubly robust estimators of causal exposure effects with missing data in the outcome, exposure or a confounder

We consider the estimation of the causal effect of a binary exposure on a continuous outcome. Confounding and missing data are both likely to occur in practice when observational data are used to estimate this causal effect. In dealing with each of these problems, model misspecification is likely to introduce bias. We present augmented inverse probability weighted (AIPW) estimators that account for both confounding and missing data, with the latter occurring in a single variable only. These estimators have an element of robustness to misspecification of the models used. Our estimators require two models to be specified to deal with confounding and two to deal with missing data. Only one of each of these models needs to be correctly specified. When either the outcome or the exposure of interest is missing, we derive explicit expressions for the AIPW estimator. When a confounder is missing, explicit derivation is complex, so we use a simple algorithm, which can be applied using standard statistical software, to obtain an approximation to the AIPW estimator.

The impact of sport and active recreation injuries on physical activity levels at 12 months post-injury

The aim of this study was to evaluate the impact of serious sport and active recreation injury on 12-month physical activity levels. Adults admitted to hospital with sport and active recreation-related injuries, and captured by the Victorian Orthopaedic Trauma Outcomes Registry were recruited to the study. Changes between preinjury and 12 month post-injury physical activity was assessed using the short International Physical Activity Questionnaire (IPAQ). Independent demographic, injury, and hospital variables were assessed for associations with changes in physical activity levels, using multivariate linear regression. A total of 324 patients were recruited, of which 98% were followed up at 12 months. Mean short IPAQ scores decreased from 7650 METS (95% CI: 7180, 8120) preinjury to 3880 METS; (95% CI: 3530, 4250) post-injury, independent of functional recovery. Education level and occupation group were the only variables independently associated with changes in physical activity levels post-injury. These results highlighted that sport and active recreation injuries lead to significant reductions in physical activity levels. Hence, the prevention of sport and active recreation injuries is important when considering promotion of activity at a population level.

Development of donor yield models

Increasing donor yield, or the number of organs transplanted per donor, has been a focus of the transplant community in recent years. However, an exclusive focus on observed yield, unadjusted for the donor characteristics, ignores important differences between donors and donor case mixes in donation service areas (DSAs). We analyzed deceased donor registry data from the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients from January 2006 to December 2009 (N = 32 116 donors). Overall yields and kidney yields were modeled using ordinal logistic regression, and logistic regression was used to model heart, lung, pancreas and liver yields. Donor characteristics, including demographics, historical information and positive serology were related to overall and organ-specific yield. This study shows the potential value of the yield models as evaluation metrics and as tools that can inform DSA-wide practices in donor management and can improve organ utilization.

Maximizing efficiency and cost-effectiveness of Type 2 diabetes screening: the AusDiab study

AIMS

  To evaluate how to most efficiently screen populations to detect people at high risk of incident Type 2 diabetes and those with prevalent, but undiagnosed, Type 2 diabetes.

METHODS

  Data from 5814 adults in the Australian Diabetes, Obesity and Lifestyle study were used to examine four different types of screening strategies. The strategies incorporated various combinations of cut-points of fasting plasma glucose, the non-invasive Australian Type 2 Diabetes Risk Assessment Tool (AUSDRISK1) and a modified version of the tool incorporating fasting plasma glucose (AUSDRISK2). Sensitivity, specificity, positive predictive value, screening costs per case of incident or prevalent undiagnosed diabetes identified and intervention costs per case of diabetes prevented or reverted were compared.

RESULTS

  Of the four strategies that maximized sensitivity and specificity, use of the non-invasive AUSDRISK1, followed by AUSDRISK2 in those found to be at increased risk on AUSDRISK1, had the highest sensitivity (80.3%; 95% confidence interval 76.6-84.1%), specificity (78.1%; 95% confidence interval 76.9-79.2%) and positive predictive value (22.3%; 95% confidence interval 20.2-24.4%) for identifying people with either prevalent undiagnosed diabetes or future incident diabetes. It required the fewest people (24.1%; 95% confidence interval 23.0-25.2%) to enter lifestyle modification programmes, and also had the lowest intervention costs and combined costs of running screening and intervention programmes per case of diabetes prevented or reverted.

CONCLUSIONS

  Using a self-assessed diabetes risk score as an initial screening step, followed by a second risk score incorporating fasting plasma glucose, would maximize efficiency of identifying people with undiagnosed Type 2 diabetes and those at high risk of future diabetes.