Cohort Profile: The North West Adelaide Health Study (NWAHS)

Predicting Slow Walking Speed From a Pooled Cohort Analysis: Sarcopenia Definitions, Agreement, and Prevalence in Australia and New Zealand

BACKGROUND

Recent operational definitions of sarcopenia have not been replicated and compared in Australia and New Zealand (ANZ) populations. We aimed to identify sarcopenia measures that discriminate ANZ adults with slow walking speed (<0.8 m/s) and determine the agreement between the Sarcopenia Definitions and Outcomes Consortium (SDOC) and revised European Working Group for Sarcopenia in Older People (EWGSOP2) operational definitions of sarcopenia.

METHODS

Eight studies comprising 8 100 ANZ community-dwelling adults (mean age ± standard deviation, 62.0 ± 14.4 years) with walking speed, grip strength (GR), and lean mass data were combined. Replicating the SDOC methodology, 15 candidate variables were included in sex-stratified classification and regression tree models and receiver operating characteristic curves on a pooled cohort with complete data to identify variables and cut points discriminating slow walking speed (<0.8 m/s). Agreement and prevalence estimates were compared using Cohen's Kappa (CK).

RESULTS

Receiver operating characteristic curves identified GR as the strongest variable for discriminating slow from normal walking speed in women (GR <20.50 kg, area under curve [AUC] = 0.68) and men (GR <31.05 kg, AUC = 0.64). Near-perfect agreement was found between the derived ANZ cut points and SDOC cut points (CK 0.8-1.0). Sarcopenia prevalence ranged from 1.5% (EWGSOP2) to 37.2% (SDOC) in women and 1.0% (EWGSOP2) to 9.1% (SDOC) in men, with no agreement (CK <0.2) between EWGSOP2 and SDOC.

CONCLUSIONS

Grip strength is the primary discriminating characteristic for slow walking speed in ANZ women and men, consistent with findings from the SDOC. Sarcopenia Definitions and Outcomes Consortium and EWGSOP2 definitions showed no agreement suggesting these proposed definitions measure different characteristics and identify people with sarcopenia differently.

Pregnancy Complications Are Associated with Premature Coronary Artery Disease: Linking Three Cohorts

Background: There is increasing evidence that women who experience placenta-mediated pregnancy complications and gestational diabetes mellitus (GDM) are at higher risk for the development of coronary artery disease (CAD) later in life. We hypothesized that there is an association between placenta-mediated pregnancy complications, GDM, and risk of premature CAD (PCAD). Methods: This research project involved a data linkage approach merging three databases of South Australian cohorts by using a retrospective, age-matched case-control study design. Cases (n = 721) were ascertained from the Coronary Angiogram Database of South Australia (CADOSA). Women <60 years from CADOSA were linked to South Australian Perinatal Statistics Collection (SAPSC) to ascertain their prior pregnancy outcomes. Controls (n = 194) were selected from North West Adelaide Health Study (NWAHS) and comprised women who were healthy or had other health conditions unrelated to CAD, age-matched to CADOSA (±5 years), and linked to SAPSC to determine their pregnancy outcomes. PCAD was defined as >50% stenosis in one or more coronary arteries at coronary angiography. Results: Compared with women without a history of PCAD, women who were diagnosed with PCAD were more likely to have experienced the placenta-mediated pregnancy complications of preterm birth (adjusted odds ratio [OR] = 2.46, 95% confidence interval [CI]: 1.21-5.00) or low-birth weight (adjusted OR = 2.44, 95% CI: 1.22-4.88), or have been diagnosed with active asthma during pregnancy (adjusted OR = 3.52, 95% CI: 1.05-11.76). Conclusion: Placenta-mediated pregnancy complications should be recognized as clear risk markers for future PCAD.

Association of dietary and nutrient patterns with systemic inflammation in community dwelling adults

Purpose

Evidence investigating associations between dietary and nutrient patterns and inflammatory biomarkers is inconsistent and scarce. Therefore, we aimed to determine the association of dietary and nutrient patterns with inflammation.

Methods

Overall, 1,792 participants from the North-West Adelaide Health Study were included in this cross-sectional study. We derived dietary and nutrient patterns from food frequency questionnaire data using principal component analysis. Multivariable ordinal logistic regression determined the association between dietary and nutrient patterns and the grade of inflammation (normal, moderate, and severe) based on C-reactive protein (CRP) values. Subgroup analyses were stratified by gender, obesity and metabolic health status.

Results

In the fully adjusted model, a plant-sourced nutrient pattern (NP) was strongly associated with a lower grade of inflammation in men (OR_Q5vsQ1 = 0.59, 95% CI: 0.38–0.93, p-trend = 0.08), obesity (OR_Q5vsQ1 = 0.43; 95% CI: 0.24–0.77, p-trend = 0.03) and metabolically unhealthy obesity (OR_Q5vsQ1 = 0.24; 95% CI: 0.11–0.52, p-trend = 0.01). A mixed NP was positively associated with higher grade of inflammation (OR_Q5vsQ1 = 1.35; 95% CI: 0.99–1.84, p-trend = 0.03) in all participants. A prudent dietary pattern was inversely associated with a lower grade of inflammation (OR_Q5vsQ1 = 0.72, 95% CI: 0.52–1.01, p-trend = 0.14). In contrast, a western dietary pattern and animal-sourced NP were associated with a higher grade of inflammation in the all participants although BMI attenuated the magnitude of association (OR_Q5vsQ1 = 0.83, 95% CI: 0.55–1.25; and OR_Q5vsQ1 = 0.94, 95% CI: 0.63–1.39, respectively) in the fully adjusted model.

Conclusion

A plant-sourced NP was independently associated with lower inflammation. The association was stronger in men, and those classified as obese and metabolically unhealthy obese. Increasing consumption of plant-based foods may mitigate obesity-induced inflammation and its consequences.

Ultrasound Imaging Acquisition Procedures for Evaluating the First Metatarsophalangeal Joint: A Scoping Review

The aim of this scoping review was to investigate ultrasound imaging (USI) acquisition procedures and guidelines used to assess the first metatarsophalangeal joint (MTPJ). MEDLINE, CINAHL, AMED and SPORTDiscus were systematically searched in May 2021. Studies were included if they used grey-scale USI or power Doppler and reported a USI procedure to assess the first MTPJ. Screening and data extraction were performed by two independent assessors. The scoping review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping reviews (PRISMA-ScR). A total of 403 citations were identified for screening, with 36 articles included in the final analysis. There was wide variation in USI acquisition procedures used to evaluate the first MTPJ. Inconsistencies in reporting may be attributable to the number of elements the USI acquisition procedure encompasses, which include the model of the USI device, the type of transducer, USI modalities and settings, patient position, transducer orientation, surfaces scanned and the scanning technique used. The review found inconsistencies against international guidelines and limited implementation of consensus-based recommendations to guide image acquisition. Current guidelines require further refinement of anatomical reference points to establish a standardised USI acquisition procedure, subsequently improving interpretability and reproducibility between USI studies that evaluate the first MTPJ.

Association between Dietary Inflammatory Index, Dietary Patterns, Plant-Based Dietary Index and the Risk of Obesity

Evidence on the association between various dietary constructs and obesity risk is limited. This study aims to investigate the longitudinal relationship between different diet indices and dietary patterns with the risk of obesity. Non-obese participants (n = 787) in the North West Adelaide Health Study were followed from 2010 to 2015. The dietary inflammatory index (DII^®), plant-based dietary index (PDI) and factor-derived dietary pattern scores were computed based on food frequency questionnaire data. We found the incidence of obesity was 7.62% at the 5-year follow up. In the adjusted model, results from multivariable log-binomial logistic regression showed that a prudent dietary pattern (RR_Q5 vs. _Q1 = 0.38; 95% CI: 0.15–0.96), healthy PDI (RR = 0.31; 95% CI: 0.12–0.77) and overall PDI (RR = 0.56; 95% CI: 0.23–1.33) were inversely associated with obesity risk. Conversely, the DII (RR = 1.59; 95% CI: 0.72–3.50), a Western dietary pattern (RR = 2.16; 95% CI: 0.76–6.08) and unhealthy PDI (RR = 1.94; 95% CI: 0.81–4.66) were associated with increased risk of obesity. Based on the cubic spline analysis, the association between an unhealthy PDI or diet quality with the risk of obesity was non-linear. In conclusion, an anti-inflammatory diet, healthy diet or consumption of healthy plant-based foods were all associated with a lower risk of developing obesity.

Predicting Australian Adults at High Risk of Cardiovascular Disease Mortality Using Standard Risk Factors and Machine Learning

Effective cardiovascular disease (CVD) prevention relies on timely identification and intervention for individuals at risk. Conventional formula-based techniques have been demonstrated to over- or under-predict the risk of CVD in the Australian population. This study assessed the ability of machine learning models to predict CVD mortality risk in the Australian population and compare performance with the well-established Framingham model. Data is drawn from three Australian cohort studies: the North West Adelaide Health Study (NWAHS), the Australian Diabetes, Obesity, and Lifestyle study, and the Melbourne Collaborative Cohort Study (MCCS). Four machine learning models for predicting 15-year CVD mortality risk were developed and compared to the 2008 Framingham model. Machine learning models performed significantly better compared to the Framingham model when applied to the three Australian cohorts. Machine learning based models improved prediction by 2.7% to 5.2% across three Australian cohorts. In an aggregated cohort, machine learning models improved prediction by up to 5.1% (area-under-curve (AUC) 0.852, 95% CI 0.837–0.867). Net reclassification improvement (NRI) was up to 26% with machine learning models. Machine learning based models also showed improved performance when stratified by sex and diabetes status. Results suggest a potential for improving CVD risk prediction in the Australian population using machine learning models.

Sleep Duration Moderates the Relationship Between Perceived Work-Life Interference and Depressive Symptoms in Australian Men and Women from the North West Adelaide Health Study

BACKGROUND

Mental health disorders are prevalent and costly to workplaces and individuals in Australia. Work-life interference is thought to contribute negatively. The interplay between work-life interference, depressive symptoms and sleep has not been explored to date in population data. The aims of this study were to establish whether sleep duration moderates the relationship between work-life interference and depressive symptoms, and whether this is expressed differentially in male and female respondents.

METHODS

Data were drawn from the North West Adelaide Health Study (NWAHS) longitudinal, representative population-based cohort study. Working members of the cohort were invited to participate in a telephone survey about their work conditions, with an 86.7% response rate achieved. Data from 823 respondents were analysed after employing purposeful selection of covariates, using multivariable regression analysis.

RESULTS

Sleep duration was found to moderate the relationship between work-life interference and depressive symptoms (F_7,815 = 26.60, p < 0.001), and accounted for 19% of the variance observed in depressive symptoms. The strongest effect of work-life interference on depressive symptoms was observed in habitual short sleepers, with the effect weakening as sleep duration increased. The relationship was observed in male and female respondents, but was stronger in females.

CONCLUSIONS

Supporting and educating workers about the benefits of sleep for managing the relationship between work-life interference and depressive symptoms may offer a novel strategy for improving worker well-being, particularly when negative facets of work-life interference are not easily remedied or 'reduced'. There is a need for education and support strategies around sleep in Australian workplaces.

Dietary inflammatory index (DII®) and the risk of depression symptoms in adults

BACKGROUND & AIMS

Findings from observational studies investigating the association between Dietary Inflammatory Index (DII®) scores and depression symptoms (DepS) are inconsistent. This study aims to assess the association between energy-adjusted DII (E-DII™) and DepS using the North West Adelaide Health Study (NWAHS) cohort as well as update a previous meta-analysis.

METHODS

A total of 1743 (mean ± SD age: 56.6 ± 13.6 years, 51% female) study participants from NWAHS were included in the cross-sectional study and 859 (mean ± SD age: 58.4 ± 12.1 years, 52.6% female) in the longitudinal analyses. The Center for Epidemiological Studies Depression Scale (CES-D) was used for the measurement of DepS. E-DII scores were calculated from the dietary data collected using a validated food frequency questionnaire (FFQ). Data from two stages [Stage 3 (2008-10) and North West 15 (NW15) (2015)] were used. Log- and negative binomial regression were used to assess the association between quartiles of E-DII and DepS. A recent meta-analysis was updated by including 12 publications (six cross-sectional and six cohort studies) on the association between DII and DepS.

RESULTS

In the cross-sectional analysis, a higher E-DII score (i.e., more pro-inflammatory diet) was associated with a 79% increase in odds of reporting DepS [OR_Quartile4vs1: 1.79; 95% CI: 1.14-2.81; p = 0.01; p for trend (p_trend) = 0.03]. Males with higher E-DII had a more than two-fold higher odds of DepS (OR_Quartile4vs1: 2.27; 95% CI: 1.02-5.06; p = 0.045; p_trend = 0.09). Females with higher E-DII had an 81% increase in odds of DepS (OR_Quartile4vs1: 1.81; 95% CI: 1.01-3.26; p = 0.046; p_trend = 0.07). These associations were consistent in the longitudinal analysis. Comparing highest to lowest quintiles of E-DII, the updated meta-analysis showed that a pro-inflammatory diet is associated with a 45% increase in odds of having DepS (OR: 1.45; 95% CI: 1.20-1.74; p < 0.01) with higher odds in females (OR: 1.53; 95% CI: 1.16-2.01; p = 0.01) compared to their male counterparts (OR: 1.29; 95% CI: 0.98-1.69; p = 0.15).

CONCLUSION

The data from the NWAHS and the updated meta-analysis of observational studies provide further evidence that a pro-inflammatory diet is positively associated with increased risk of DepS. These findings support the current recommendation on consuming a less inflammatory diet to improve DepS.

Frailty and sarcopenia in combination are more predictive of mortality than either condition alone

BACKGROUND

Frailty and sarcopenia are age-related conditions with shared features and are both associated with adverse health outcomes. Relatively little is known about outcomes of these conditions in combination. The aim of this study was to examine the predictive ability of combined frailty and sarcopenia classification on mortality.

METHODS

Frailty was measured in 716 community-dwelling adults aged ≥65 years from the North West Adelaide Health Study (mean age 74.1(6.1) years, 55.5 % female) using the frailty phenotype (FP) and sarcopenia using the revised consensus definition from the European Working Group on Sarcopenia. Participants were classified as: neither frail nor sarcopenic, frail-only, sarcopenic-only, or both frail and sarcopenic. All participants had a minimum of 10 years of mortality follow-up.

RESULTS

We identified 2.8 % of participants as both frail and sarcopenic, 15.5 % as frail-only, and 3.5 % as sarcopenic-only. Classification as both frail and sarcopenic, in a multivariable model, resulted in significantly elevated mortality risk (HR = 3.52, p < .001), which was over three times that of those neither frail nor sarcopenic. Frail-only was also a significant mortality predictor (HR = 2.03, p = .001), while classification as sarcopenic-only was not a significant predictor of mortality (HR = 1.65, p = .141). There was no significant difference in severity of frailty (mean number of characteristics) or grip strength between frail-only and those with both conditions when stratified by sex.

CONCLUSIONS

Individuals identified as frail would benefit from screening and assessment for sarcopenia, and vice versa for those identified as sarcopenic, as the mortality risk for individuals with these conditions in combination is nearly double that of each separately.

Shoulder range of movement in the general population: age and gender stratified normative data using a community-based cohort

Background

An understanding of the average range of movement of the shoulder that is normally achievable is an important part of treatment for shoulder disorders. The average range of active shoulder flexion, abduction and external rotation was measured in a population cohort aged 20 years and over without shoulder pain and/or stiffness in order to provide normative shoulder range data.

Methods

Cross-sectional analysis using participants in a community-based longitudinal cohort study. There have been three stages of data collection – Stage 1 (1999–2003), Stage 2 (2004–2006) and Stage 3 (2008–2010). Each stage has consisted a of broad ranging computer assisted telephone interview, a self-complete questionnaire and a clinic assessment. Participants in this study are those who undertook assessments in Stage 2. The main outcome measures were active shoulder range of movement (flexion, abduction and external rotation) measured as part of the clinic assessment using a Plurimeter V inclinometer. Mean values were determined and analyses to examine differences between groups (sex and age) were undertaken using non-parametric tests.

Results

There were 2404 participants (51.5% male), mean age 45.8 years (SD 17.3, range 20–91). The average range of active right shoulder flexion was 161.5° for males and 158.5° for females, and active right shoulder abduction was 151.5° and 149.7° for males and females respectively. Shoulder range of movement declined with age, with mean right active shoulder flexion decreasing by 43° in males and 40.6° in females and right active shoulder abduction by 39.5° and 36.9° respectively. External rotation range also declined, particularly among females.

Conclusion

To our knowledge this is the largest community-based study providing normative data for active shoulder range of movement. This information can be used to set realistic goals for both clinical practice and clinical trials.

Association of metabolic phenotypes, grip strength and diabetes risk: The 15-year follow-up of The North West Adelaide Health Study, Australia

BACKGROUND

The association of diabetes risk in the long-term, metabolic phenotypes (MP) and muscle strength is unclear. We aimed to investigate the association between strictly defined MP, grip strength (GS) and diabetes.

MATERIAL AND METHODS

MP were defined according to BMI and presence of any individual metabolic abnormality for ≥18 years, in participants of the North West Adelaide Health Study (Australia) free of diabetes at baseline. The association of MP and dominant hand GS with incident diabetes over 15-years follow-up and the moderation effect of GS on the association between diabetes and MP were investigated by logistic regression models.

RESULTS

Of 3039 participants followed over 13.3 years (SD 2.6), 236 (7.8%) developed diabetes. Compared to the metabolically healthy (MH) normal weight phenotype, the metabolically unhealthy (MU) overweight (OR 6.15, 95%CI 2.43-15.59) and obese (OR 12.32, 95%CI 4.97-30.52) phenotypes were associated with a high risk of diabetes, but not the MU normal weight (OR 1.73, 95%CI 0.57-5.25), MH overweight (OR 1.15, 95%CI 0.31-4.31) or MH obese phenotypes (OR 0.77, 0.07-8.89). GS was inversely associated with diabetes (OR 0.97, 95% CI 0.95-0.99) and attenuated the risk associated with MU overweight (beta = -0.296, p = 0.039) and MU normal weight (beta = -0.773; p for interaction = 0.009).

CONCLUSION

Strictly defined MP (rather than based on metabolic syndrome criteria) and GS, a proxy of muscle strength, might be useful for stratifying the risk of diabetes in the long-term. Improving muscle strength might be an important strategy to reduce diabetes risk.

FRAIL scale: Predictive validity and diagnostic test accuracy

OBJECTIVE

To examine the predictive validity of the FRAIL scale for mortality, and diagnostic test accuracy (DTA) against the frailty phenotype (FP).

MEASUREMENT

Frailty was measured in 846 community-dwelling adults (mean age 74.3 [SD 6.3] years, 54.8% female) using a modified FRAIL scale and modified FP. Mortality was matched to death records.

RESULTS

The FRAIL scale demonstrated significant predictive validity for mortality up to 10 years (Frail adjHR: 2.60, P < .001). DTA findings were acceptable for specificity (86.8%) and Youden index (0.50), but not sensitivity (63.6%), or area under the receiver operator curve (auROC) (0.75). DTA estimates were more acceptable when a cut-point of ≥2 characteristics was used rather than ≥3 in the primary DTA analysis.

CONCLUSION

The FRAIL scale is a valid predictor of mortality. DTA estimates depend on FRAIL scale cut-point used. This instrument is a potentially useful frailty screening tool.

Associations between area socioeconomic status, individual mental health, physical activity, diet and change in cardiometabolic risk amongst a cohort of Australian adults: A longitudinal path analysis

Presumed pathways from environments to cardiometabolic risk largely implicate health behaviour although mental health may play a role. Few studies assess relationships between these factors. This study estimated associations between area socioeconomic status (SES), mental health, diet, physical activity, and 10-year change in glycosylated haemoglobin (HbA_1c), comparing two proposed path structures: 1) mental health and behaviour functioning as parallel mediators between area SES and HbA_1c; and 2) a sequential structure where mental health influences behaviour and consequently HbA_1c. Three waves (10 years) of population-based biomedical cohort data were spatially linked to census data based on participant residential address. Area SES was expressed at baseline using an established index (SEIFA-IEO). Individual behavioural and mental health information (Wave 2) included diet (fruit and vegetable servings per day), physical activity (meets/does not meet recommendations), and the mental health component score of the 36-item Short Form Health Survey. HbA_1c was measured at each wave. Latent variable growth models with a structural equation modelling approach estimated associations within both parallel and sequential path structures. Models were adjusted for age, sex, employment status, marital status, education, and smoking. The sequential path model best fit the data. HbA_1c worsened over time. Greater area SES was statistically significantly associated with greater fruit intake, meeting physical activity recommendations, and had a protective effect against increasing HbA_1c directly and indirectly through physical activity behaviour. Positive mental health was statistically significantly associated with greater fruit and vegetable intakes and was indirectly protective against increasing HbA_1c through physical activity. Greater SES was protective against increasing HbA_1c. This relationship was partially mediated by physical activity but not diet. A protective effect of mental health was exerted through physical activity. Public health interventions should ensure individuals residing in low SES areas, and those with poorer mental health are supported in meeting physical activity recommendations.

Nutrient patterns and depressive symptoms among Australian adults

PURPOSE

Much of the current literature on the associations between diet and depression focus on single nutrients rather than nutrient patterns (NPs). We investigated the association between NPs and depressive symptoms (DepS) in an Australian adult population.

METHODS

DepS were examined at two different time points, in 2010 (Stage 3, n = 1743, 49.0% males) and 2015 [North West 2015 (NW15), n = 1,024, 46.6% males] of the North West Adelaide Health Study (NWAHS). Dietary habits were evaluated using a food frequency questionnaire (FFQ) at Stage 3. DepS were assessed using the Center for Epidemiological Studies Depression (CES-D) scale at Stage 3 and NW15. Principal component analysis was used to identify NPs as well as the factor structure of the CES-D. Log- and negative binomial regression analyses were used to assess the association between NPs and DepS scores. Ordinal logistic regression analysis was undertaken between the NPs and identified factors of the CES-D score.

RESULTS

Three NPs (from the FFQ) and two-factors (from the CES-D score) were obtained. After adjusting for known confounding variables, a 'plant-sourced' NP (β-carotene, fibre, vitamin C, potassium and α-carotene) was inversely associated with DepS at Stage 3 [prevalence ratio (PR)_Q4VsQ1, 0.78; 95% CI 0.66-0.92; p = 0.003], whereas an 'animal-sourced' (ω-3 fatty acid, monounsaturated fat, vitamin E and cholesterol) or 'mixed-source' (phosphorous, protein, vitamin B2, iodine and zinc) NP was not associated with DepS. There was an inverse relationship between the 'plant-sourced' NP and the '(absence of) positive-affect' factor from the CES-D in both stages.

CONCLUSION

The 'plant-sourced' NP is consistently and inversely associated with DepS; however, longitudinal studies are recommended to confirm these results.

Contributions of Multiple Built Environment Features to 10-Year Change in Body Mass Index and Waist Circumference in a South Australian Middle-Aged Cohort

Residential areas may shape health, yet few studies are longitudinal or concurrently test relationships between multiple residential features and health. This longitudinal study concurrently assessed the contributions of multiple environmental features to 10-year change in clinically measured body mass index (BMI) and waist circumference (WC). Longitudinal data for adults (18+ years of age, n = 2253) from the north-west of Adelaide, Australia were linked to built environment measures representing the physical activity and food environment (expressed for residence-based 1600 m road-network buffers) and area education. Associations were concurrently estimated using latent growth models. In models including all environmental exposure measures, area education was associated with change in BMI and WC (protective effects). Dwelling density was associated with worsening BMI and WC but also highly correlated with area education and moderately correlated with count of fast food outlets. Public open space (POS) area was associated with worsening WC. Intersection density, land use mix, greenness, and a retail food environment index were not associated with change in BMI or WC. This study found greater dwelling density and POS area exacerbated increases in BMI and WC. Greater area education was protective against worsening body size. Interventions should consider dwelling density and POS, and target areas with low SES.

Are changes in depressive symptoms, general health and residential area socio-economic status associated with trajectories of waist circumference and body mass index?

Objective

This study sought to assess whether changes in depressive symptoms, general health, and area-level socio-economic status (SES) were associated to changes over time in waist circumference and body mass index (BMI).

Methods

A total of 2871 adults (18 years or older), living in Adelaide (South Australia), were observed across three waves of data collection spanning ten years, with clinical measures of waist circumference, height and weight. Participants completed the Centre for Epidemiologic Studies Depression (CES-D) and Short Form 36 health questionnaires (SF-36 general health domain). An area-level SES measure, relative location factor, was derived from hedonic regression models using residential property features but blind to location. Growth curve models with latent variables were fitted to data.

Results

Waist circumference, BMI and depressive symptoms increased over time. General health and relative location factor decreased. Worsening general health and depressive symptoms predicted worsening waist circumference and BMI trajectories in covariate-adjusted models. Diminishing relative location factor was negatively associated with waist circumference and BMI trajectories in unadjusted models only.

Conclusions

Worsening depressive symptoms and general health predict increasing adiposity and suggest the development of unhealthful adiposity might be prevented by attention to negative changes in mental health and overall general health.

Prevalence of Foot Pain Across an International Consortium of Population-Based Cohorts

Objective

Despite the potential burden of foot pain, some of the most fundamental epidemiologic questions surrounding the foot remain poorly explored. The prevalence of foot pain has proven to be difficult to compare across existing studies due to variations in case definitions. The objective of this study was to investigate the prevalence of foot pain in several international population‐based cohorts using original data and to explore differences in the case definitions used.

Methods

Foot pain variables were examined in 5 cohorts: the Chingford 1000 Women Study, the Johnston County Osteoarthritis Project, the Framingham Foot Study, the Clinical Assessment Study of the Foot, and the North West Adelaide Health Study. One question about foot pain was chosen from each cohort based on its similarity to the American College of Rheumatology pain question.

Results

The precise definition of foot pain varied between the cohorts. The prevalence of foot pain ranged from 13% to 36% and was lowest in the cohort in which the case definition specific to pain was used, compared to the 4 remaining cohorts in which a definition included components of pain, aching, or stiffness. Foot pain was generally more prevalent in women and obese individuals and generally increased with age, with the prevalence being much lower in younger participants (ages 20–44 years).

Conclusion

Foot pain is common and is associated with female sex, older age, and obesity. Estimates of the prevalence of foot pain are likely to be affected by the case definition used. Therefore, in future population studies, the use of consistent measures of data collection must be considered.

Associations of OSA and Nocturnal Hypoxemia with Strength and Body Composition in Community Dwelling Middle Aged and Older Men

PURPOSE

Reduced hand grip strength (HGS) is associated with poorer health in chronic conditions, yet there has been little research examining the association with hand grip strength and obstructive sleep apnea (OSA). Further, these studies have not examined, nor adjusted, for muscle mass. The aim of this study was to determine associations between OSA indices, HGS, muscle mass, and fat mass.

PARTICIPANTS AND METHODS

A total of 613 participants (age range 41-88, BMI 28.6 ± 4.3) from the population-based Men Androgen Inflammation Lifestyle Environment and Stress Study underwent in-home overnight polysomnography, assessment of dominant and non-dominant HGS, and dual x-ray absorptiometry to determine whole body muscle mass and fat mass. Linear models determined cross-sectional associations of polysomnographic-derived OSA indices with hand grip strength, muscle mass, and fat mass, whilst adjusting for lifestyle information (income, smoking status, diet, self-reported physical activity), blood sample derived testosterone and systemic inflammation (C-reactive protein), cardiometabolic health (cardiovascular disease, hypertension, type 2 diabetes), and depression.

RESULTS

In adjusted models, reduced dominant HGS was associated with lower oxygen nadir (unstandardised β [B] = 0.19, 95% confidence interval [CI] 0.08 to 0.29), greater time spent below 90% oxygen saturation (B = -0.08, 95% CI -0.14 to -0.02), and increased apnea duration (B = -0.3, 95% CI -0.23 to -0.02). By contrast, there were no associations between HGS and both AHI and REM AHI. Fat mass was consistently associated with worsening OSA indices, whereas muscle mass demonstrated no associations with any OSA index.

CONCLUSION

Our findings suggest impairments in HGS may be related to fat infiltration of muscle, hypoxemia-induced reductions in peripheral neural innervation, or even endothelial dysfunction, which is a common outcome of hypoxemia. Longitudinal data are needed to further examine these hypotheses and establish if reduced grip strength in patients with OSA is associated with long-term adverse health outcomes.

Association between dietary patterns and adult depression symptoms based on principal component analysis, reduced-rank regression and partial least-squares

BACKGROUND & AIMS

There have been inconsistent findings on the association between dietary patterns and depressive symptoms (DepS). In addition, studies have used single analysis methods to identify dietary patterns. In the current study, we aimed to determine the association between dietary patterns, derived by principal component analysis (PCA), reduced-rank regressions (RRR) and partial least-squares (PLS), and DepS among adults using a cohort study in Australia.

METHODS

We examined a total of 1743 study participants (≥24 years, 48.9% males) using cross-sectional and longitudinal data from the North West Adelaide Health Study (NWAHS). The Center for Epidemiological Studies-Depression (CES-D) scale was used to assess DepS and a score ≥16 was considered as having depression. Dietary data were collected using a food frequency questionnaire. Eicosapentaenoic acid (EPA)/Docosahexaenoic acid (DHA), folate, magnesium (Mg) and zinc (Zn) densities were chosen as the response variables for RRR and PLS analyses. Dietary patterns were identified by PCA, RRR and PLS. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated across quartiles (Q) using log-binomial logistic regression to assess the association between dietary patterns and DepS. Sensitivity analyses, including a longitudinal association between dietary patterns and DepS among 859 participants, were performed. Multiple imputation was performed to investigate the effect of missing data on the estimates.

RESULTS

In this study, 16.9% (14.2% in men and 20.8% in women) of the participants had DepS. We retained two, four and four dietary patterns captured by PCA, RRR and PLS respectively. The 'prudent' pattern determined by PCA [OR_Q4VsQ1 = 0.57; 95% CI: 0.35, 0.92] and PLS [OR_Q4VsQ1 = 0.66; 95% CI: 0.43, 1.00] together with the 'typical Australian' pattern determined by RRR [OR_Q4VsQ1 = 0.60; 95% CI: 0.40, 0.90] were inversely associated with DepS whereas the 'western' pattern derived by PCA [OR_Q4VsQ1 = 2.04; 95% CI: 1.12, 3.68] and PLS [OR_Q4VsQ1 = 1.62; 95% CI: 1.05, 2.50] was positively associated with DepS. In the longitudinal analysis, the 'prudent' pattern determined by PCA [OR_Q4VsQ1 = 0.52; 95% CI: 0.25, 1.09] tended to be inversely associated with DepS whereas 'western' patterns determined by PCA [OR_Q4VsQ1 = 3.47; 95% CI: 1.37, 8.78] and PLS [OR_Q4VsQ1 = 2.47; 95% CI: 1.24, 4.91] were positively associated with DepS. We found that a dietary pattern characterized by high intakes of fruits, vegetables, medium fat dairy, nuts, legumes, and fish was inversely associated with DepS in this population-based study. Contrary to this, a dietary pattern characterized by high intakes of processed and red meat, fast foods (snacks and takeaway foods), soft drinks, white bread and high-fat dairy products were significantly associated with DepS. Multiple imputation and sensitivity analysis identified similar patterns of association between dietary pattern and DepS.

CONCLUSIONS

The findings indicate that the 'western' pattern was consistently associated with an increased risk, and the 'prudent' pattern tended to be associated with a reduced risk of DepS. This suggests that dietary interventions may assist with the treatment of DepS. However, current evidence on the impact of diet on DepS should be supported using further longitudinal studies with extended follow up, larger sample sizes and repeated measures.

Association between Macronutrient Intake and Excessive Daytime Sleepiness: An Iso-Caloric Substitution Analysis from the North West Adelaide Health Study

Epidemiological evidence on the association between macronutrient intake and excessive daytime sleepiness (EDS) is scarce. Using data from the North West Adelaide Health Study, we aimed to determine the association between iso-caloric substitution of macronutrients and EDS. Data from 1997 adults aged ≥ 24 years were analyzed. Daytime sleepiness was measured using the Epworth Sleepiness Scale, a score ≥ 11 was considered EDS. Dietary intake data were collected using a food frequency questionnaire. We determined absolute and relative energy intake based on consumption of saturated and unsaturated fats, protein, and carbohydrate. Odds ratios (ORs) were used to determine the associations using log-binomial logistic regression with and without iso-caloric substitution methods, and models were adjusted for confounders. The prevalence of EDS in the sample was 10.6%. After adjusting for potential confounders, substituting 5% energy intake from protein with an equal amount of saturated fat (OR = 1.57; 95% CI: 1.00–2.45) and carbohydrate (OR = 1.23; 95% CI: 0.92–1.65) increased the odds of EDS. When carbohydrate was substituted with saturated fat (OR = 1.27; 95% CI: 0.93–1.59), the odds of EDS were increased. The odds of EDS were lower when saturated fat was substituted with unsaturated fat (OR = 0.74; 95% CI: 0.51–1.06), protein (OR = 0.63; 95% CI: 0.41–0.99) or carbohydrate (OR = 0.79; 95% CI: 0.57–1.08). While these results were consistent over different iso-caloric substitution methods, inconsistent results were found with standard regression. While substitution of fat and carbohydrate with protein was inversely associated with EDS, substitution of protein with fat and carbohydrate was positively associated with EDS. Randomized trials are needed to confirm if dietary interventions can be used to improve daytime alertness in those with EDS.

Sociodemographic, lifestyle and metabolic predictors of all-cause mortality in a cohort of community-dwelling population: an 18-year follow-up of the North West Adelaide Health Study

INTRODUCTION

Studies examining potential factors of all-cause mortality comprehensively at community level are rare. Using long-term community-based follow-up study, we examined the association of sociodemographic and behavioural characteristics, metabolic and chronic conditions, and medication and health service utilisation with all-cause mortality.

METHODS

We followed 4056 participants, aged 18-90 years, for 18 years in the North West Adelaide Health Study (NWAHS). Mortality data were obtained from South Australian (SA) public hospitals and registries including SA births, deaths and marriages, the National Death Index and the NWAHS follow-up. Predictors of all-cause mortality were explored using Cox proportional hazard model, adjusting for potential confounders. We performed subgroup analyses by sex and age.

RESULTS

Mean (SD) age at baseline was 50.4 (16.4) years. Less than half (47.8%) of the participants were men. A total of 64 689.7 person-years from 4033 participants with 18.7 years of follow-up were generated. The median follow-up time was 17.7 years; 614 deaths were recorded. The overall crude death rate was 9.6 (95% CI 8.9 to 10.4) per 1000 person-years. After adjusting for potential confounders, a reduced risk of mortality was significantly associated with being separated or divorced, being in the highest Socioeconomic Indexes for Areas quintile, engaging in moderate exercise, being overweight (body mass index: 25.0-29.9 kg/m²) and per 10% increase in per cent predicted forced expiratory volume in 1 s. We found that the most important predictors of all-cause mortality were sociodemographic and behavioural characteristics. Sociodemographic factors were more important predictors of all-cause mortality in young age bracket compared with older people.

CONCLUSIONS

Socioeconomic factors were found to be the most important predictors of all-cause mortality. The study highlights the need to address the social inequalities and strengthen behavioural interventions for different subgroups of population to prevent premature deaths.

Recurrent Measurement of Frailty Is Important for Mortality Prediction: Findings from the North West Adelaide Health Study

OBJECTIVES

Frailty places individuals at greater risk of adverse health outcomes. However, it is a dynamic condition and may not always lead to decline. Our objective was to determine the relationship between frailty status (at baseline and follow-up) and mortality using both the frailty phenotype (FP) and frailty index (FI).

DESIGN

Population-based cohort.

SETTING

Community-dwelling older adults.

PARTICIPANTS

A total of 909 individuals aged 65 years or older (55% female), mean age 74.4 (SD 6.2) years, had frailty measurement at baseline. Overall, 549 participants had frailty measurement at two time points.

MEASUREMENTS

Frailty was measured using the FP and FI, with a mean 4.5 years between baseline and follow-up. Mortality was matched to official death records with a minimum of 10 years of follow-up.

RESULTS

For both measures, baseline frailty was a significant predictor of mortality up to 10 years, with initially good predictive ability (area under the curve [AUC] = .8-.9) decreasing over time. Repeated measurement at follow-up resulted in good prediction compared with lower (AUC = .6-.7) discrimination of equivalent baseline frailty status. In a multivariable model, frailty measurement at follow-up was a stronger predictor of mortality compared with baseline. Frailty change for the Continuous FI was a significant predictor of decreased or increased mortality risk based on corresponding improvement or worsening of score (hazard ratio = 1.04; 95% confidence interval = 1.02-1.07; P = .001).

CONCLUSIONS

Frailty measurement is a good predictor of mortality up to 10 years; however, recency of frailty measurement is important for improved prediction. A regular review of frailty status is required in older adults. J Am Geriatr Soc 67:2311-2317, 2019.

Correlates of Discordance between Perceived and Objective Distances to Local Fruit and Vegetable Retailers

Background: Perceptions of neighbourhood attributes such as proximity of food retailers that are discordant with objective measures of the same are associated with poor health behaviours and weight gain. Factors associated with discordant perceptions are likely relevant to planning more effective interventions to improve health. Purpose: Analysis of cross-sectional relationships between individual and neighbourhood factors and overestimations of walking distances to local fruit/vegetable retailers (FVR). Methods: Perceived walking times, converted to distances, between participant residences and FVR were compared with objectively-assessed road network distances calculated with a Geographic Information System for n = 1305 adults residing in Adelaide, South Australia. Differences between perceived and objective distances were expressed as ‘overestimated’ distances and were analysed relative to perceptions consistent with objective distances. Cross-sectional associations were evaluated between individual socio-demographic, health, and area-level characteristics and overestimated distances to FVR using multilevel logistic regression. Results: Agreement between objective and perceived distances between participants’ residence and the nearest FVR was only fair (weighted kappa = 0.22). Overestimated distances to FVR were positively associated with mental well-being, and were negatively associated with household income, physical functioning, sense of community, and objective distances to greengrocers. Conclusions: Individual characteristics and features of neighbourhoods were related to overestimated distances to FVR. Sense of connectivity and shared identity may shape more accurate understandings of local resource access, and offer a focal point for tailored public health initiatives that bring people together to achieve improved health behaviour.

Unique associations of the Job Demand-Control-Support model subscales with leisure-time physical activity and dietary energy intake

Leisure-time physical activity (LTPA) and dietary energy intake are two important health behaviours, which at too low or high levels respectively, are associated with overweight and obesity. This study explores associations between subscales of the Job Demand-Control-Support (JDCS) model, LTPA and dietary energy intake. A cross-sectional design sampled current employees (N=433) from a South Australian cohort using a computer-assisted telephone interview and a self-completed food frequency questionnaire. In analyses adjusted for sex, age, and sociodemographic variables, higher levels of skill discretion were associated with increased odds for attaining sufficient physical activity (OR=2.45; 95% CI=1.10-5.47). Higher levels of decision authority were associated with reduced odds (OR=0.43; 95% CI=0.20-0.93) for being in the highest tertile of daily energy intake. Higher scores for coworker support were associated with increased odds (OR=2.20; 95% CI=1.15-4.23) for being in the highest tertile of daily energy intake. These findings support the consideration of the individual JDCS subscales, since this practice may reveal novel associations with health behaviour outcomes, thereby presenting new opportunities to improve employee health and wellbeing.

Prevalence and healthcare usage of knee pain in South Australia: a population-based study

BACKGROUND

It is known that South Australia (SA) has the highest rate of knee arthroscopy use of any state in Australia; however, Level 1 evidence demonstrates that knee arthroscopy in patients with uncomplicated knee osteoarthritis confers no benefit. In SA, which patients are presenting with knee pain and what treatments are they receiving?

AIMS

To determine the prevalence, persistence and treatment modalities of knee pain in SA.

METHODS

This study analysed data from the North-West Adelaide Health Study (1999-2015), a longitudinal, population-based cohort study of people aged 18 years and over (n = 4060), initially randomly selected from the north-west region of Adelaide, SA. It incorporated clinic assessments, self-completed questionnaires and telephone interviews to collect demographic, anthropometric and biochemical data over four main stages (1, 2, 3 and North-West 15 (NW15)). Data were linked to Medical Benefits Scheme data.

RESULTS

In stages 3 and NW15 of the North-West Adelaide Health Study, 30-35% of participants reported knee pain (n = 803, 452). Demographic variables associated with knee pain included older age and lower educational level, while risk factors included obesity and high waist circumference. In the 12 months preceding NW15, 33% of participants with knee pain/stiffness consulted a general practitioner for their knee pain, 10.2% an orthopaedic surgeon, and 12.6% a physiotherapist. Between 2011 and 2015, 3.0% the cohort underwent a knee arthroscopy, and 3.1% underwent knee magnetic resonance imaging.

CONCLUSIONS

Knee pain affects large proportions of the SA population. Knee pain was persistent with underuse of non-pharmacological treatments and high use of specialist referral. These data support the need for a national strategy to manage osteoarthritis effectively.

The healing of dental extraction sockets in insulin-dependent diabetic patients: a prospective controlled observational study

BACKGROUND

The aim of this study was to determine whether there was a difference in delayed healing following dental extractions for insulin-dependent diabetics as compared to non-diabetic patients.

METHODS

Prospective patients referred to the Adelaide Dental Hospital exodontia clinic for dental extractions were recruited into two groups: Known insulin-dependent diabetics and healthy non-diabetics. All had a random blood glucose level (BGL). Delayed healing cases were identified, and statistical evaluation was performed.

RESULTS

There were 56 insulin-dependent diabetic patients (BGL 10.03, range 4.9-26) and 49 non-diabetic, age- and sex-matched patients. Seven patients (12.5%) in the study group showed delayed healing following extraction, while only four patients (8.2%) in the control group suffered delayed healing. This difference was not statistically significant. Two of the study group developed postextraction infections, requiring incision, drainage and antibiotics.

CONCLUSION

The study shows that Type 1 and insulin-dependent Type 2 diabetic patients, if well controlled, tend to heal up well following dental extractions but with a small but not statistically different rate of postextraction complications including infection. This is contrary to what is usually taught. Clinicians should take great care with management of insulin-dependent diabetic patients, as compared to non-insulin dependent diabetics or non-diabetic patients.

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.

Frailty state transitions and associated factors in South Australian older adults

AIM

Frailty is a state of decreased physiological reserve and vulnerability to stressors. Understanding the characteristics of those most at risk of worsening, or likely to improve their frailty status, are key elements in addressing this condition. The present study measured frailty state transitions and factors associated with improvement or worsening frailty status in the North West Adelaide Health Study.

METHODS

Frailty was measured using the frailty phenotype (FP) and a 34-item frailty index (FI) for 696 community-dwelling participants aged ≥65 years, with repeated measures at 4.5-year follow up.

RESULTS

Improvement in frailty state was common for both tools (FP 15.5%; FI 7.9%). The majority remained stable (FP 44.4%; FI 52.6%), and many transitioned to a worse level of frailty (FP 40.1%; FI 39.5%). For both measures, multimorbidity was associated with worsening frailty among non-frail participants. Among pre-frail participants, normal waist circumference was associated with improvement, whereas older age was associated with worsening of frailty status. Among frail individuals, younger age was associated with improvement, and male sex and older age were associated with worsening frailty status.

CONCLUSIONS

Frailty is a dynamic process where improvement is possible. Multimorbidity, obesity, age and sex were associated with frailty transitions for both tools. Geriatr Gerontol Int 2018; 18: 1549-1555.

Association of Statin Exposure With Histologically Confirmed Idiopathic Inflammatory Myositis in an Australian Population

IMPORTANCE

Statin medications are widely prescribed for cardiovascular risk reduction. Myalgia and rhabdomyolysis are well-recognized adverse effects of statins, and they resolve with the cessation of statin therapy. Idiopathic inflammatory myositis (IIM) is a heterogeneous group of autoimmune myopathies that may also be associated with statin use. Recently, statin-associated autoimmune myopathy has been recognized as a distinct entity with the presence of specific autoantibodies against hydroxymethylglutaryl-coenzyme A reductase, which results in a necrotizing myositis that does not resolve with cessation of statin therapy and requires treatment with immunosuppressive agents.

OBJECTIVE

To examine the association between histologically confirmed IIM and current exposure to statin medications.

DESIGN, SETTING, AND PARTICIPANTS

Population-based case-control study using the South Australian Myositis Database of all histologically confirmed cases of IIM diagnosed between 1990 and 2014 in patients 40 years or older (n = 221) and population-based controls from the North West Adelaide Health Study (n = 662), matched by age and sex in a 3:1 ratio of controls to cases. Data analysis using conditional logistic regression was performed from June 1, 2016, to July 14, 2017.

EXPOSURES

Current statin medication use.

MAIN OUTCOMES AND MEASURES

Unadjusted and adjusted (for diabetes and cardiovascular disease) odds ratios and 95% CIs for likelihood of inflammatory myositis.

RESULTS

A total of 221 IIM cases met the inclusion criteria with a mean (SD) age of 62.2 (10.8) years, and 132 (59.7%) were female. Statin exposure at the time of IIM diagnosis was 68 of 221 patients (30.8%) and 142 of 662 matched controls (21.5%) (P = .005). There was an almost 2-fold increased likelihood of statin exposure in patients with IIM compared with controls (adjusted odds ratio, 1.79; 95% CI, 1.23-2.60; P = .001). Similar results were observed when patients with necrotizing myositis were excluded from the analysis (adjusted odds ratio, 1.92; 95% CI, 1.29-2.86; P = .001).

CONCLUSIONS AND RELEVANCE

In this large population-based study, statin exposure was significantly associated with histologically confirmed IIM. Given the increased use of statins worldwide and the severity of IIM, increased awareness and recognition of this potentially rare adverse effect of statin exposure is needed.

Gender-specific associations between perceived and objective neighbourhood crime and metabolic syndrome

Much research has considered the relationship between neighbourhood crime and physical activity, but few studies have assessed clinical outcomes consequent to behaviour, such as cardiometabolic risk. Fewer still have simultaneously assessed perceived and objective measures of crime. Perceptions of crime and actual victimisation vary according to gender; thus, this study sought to assess: 1) correspondence between perceived and objective neighbourhood crime; and 2) gender-specific associations between perceived and reported crime and metabolic syndrome, representing cardiometabolic risk. The indirect effect of neighbourhood crime on metabolic syndrome via walking was additionally evaluated. An Australian population-based biomedical cohort study (2004–2007) collected biomedical, socio-demographic, and neighbourhood perceptions data from n = 1,172 urban-dwelling, adults. Area-level reported crime rates were standardised and linked to individual data based on participants' residential location. Correspondence between actual and perceived crime measures was assessed using Pearson correlation coefficients. Cross-sectional associations between crime and metabolic syndrome were analysed using generalised estimating equations regression models accounting for socio-demographic factors and area-level income. Correspondence between perceived and objective crime was small to medium among men and women (r = 0.17 to 0.33). Among men, metabolic syndrome was related to rates of violent (OR = 1.21, 95% CI 1.08–1.35) and total crime (OR = 1.17, 95% CI 1.04–1.32), after accounting for perceived crime. Among women, metabolic syndrome was related to perceived crime (OR = 1.35, 95% CI 1.14–1.60) after accounting for total reported crime. Among women, there were indirect effects of perceived crime and property crime on metabolic syndrome through walking. Results indicate that crime, an adverse social exposure, is linked to clinical health status. Crime rates, and perceptions of crime and safety, differentially impact upon cardiometabolic health according to gender. Social policy and public health strategies targeting crime reduction, as well as strategies to increase perceptions of safety, have potential to contribute to improved cardiometabolic outcomes.

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 = 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] = 19.7% to 29.9%) of the burden, higher for men (36.7%) than women (13.2%, P difference < .001). The burden attributed to these factors was also higher for those born in Australia (28.7%) than elsewhere (16.8%, P difference = .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.

Physical activity moderates the deleterious relationship between cardiovascular disease, or its risk factors, and quality of life: Findings from two population-based cohort studies in Southern Brazil and South Australia

Background

Few studies have investigated the relationship between physical activity (PA) of low intensity and duration with quality of life (QoL) among individuals at risk or with cardiovascular disease (CVD).

Objectives

To investigate whether PA of different intensity and duration moderates the relationship between CVD and its risk factors (obesity, hypertension, diabetes, dyslipidaemia) and QoL in adults.

Methods

Population-based cross-sectional studies using data from the EpiFloripa Cohort Study (Southern Brazil; n = 1,220, 38.8±12.0 years, 48.2% males) and the North West Adelaide Health Study (NWAHS, South Australia; n = 1,661, 43.7±11.1 years, 49.7% males). The physical and psychological domains of QoL were assessed using the WHOQOL-Bref (EpiFloripa) or the SF-36 (NWAHS) questionnaires. The diagnosis of CVD and its risk factors were self-reported. PA was self-reported and quantified by its intensity [“walking” or moderate/vigorous (MVPA)] and duration (none, 1–150, ≥150 min/week). Both studies were analysed separately, and results were adjusted for sociodemographic variables.

Results

Participants at risk or with CVD from both studies showed a lower QoL than ‘healthy’ individuals with a stronger relationship for the physical domain. PA duration showed a direct-trend relationship with QoL, but the associations were stronger for MVPA in both studies. However, when stratified by health status, the magnitude of the association between “walking” duration and a higher physical QoL was greater among those at risk or with CVD compared to ‘healthy’ individuals. Conversely, among Australians with CVD, MVPA was associated with a better physical QoL only when its duration was ≥150 min/week. All associations were stronger in the NWAHS than in the Brazilian study.

Conclusions

“Walking” was more prevalent than MVPA and was consistently associated with a better physical QoL among those at risk or with CVD. These findings should be considered in the design of public health interventions designed to increase PA and improve QoL.

Hand grip strength measurement in different epidemiologic studies using various methods for diagnosis of sarcopenia: a systematic review

BACKGROUND

The purpose of this systematic review was to compare various methods for measuring hand grip strength to provide data for the development of a standardized protocol for such a measurement based on epidemiologic studies of sarcopenia in older population.

METHODS

Systematic review and meta-analysis were performed using 34 available epidemiologic studies.

RESULTS

The choice of hand dynamometer and measurement protocols for measuring hand grip strength was not consistent among studies. Mean values of hand grip strength in older population were also different by study area (Europe, America, and Asia) and gender.

CONCLUSION

This systematic review demonstrated that various grip strength measurement methods were used in different epidemiologic studies. A standardized method is needed to enable more consistent measurement of grip strength and better assessment of sarcopenia.

Associations between local descriptive norms for overweight/obesity and insufficient fruit intake, individual-level diet, and 10-year change in body mass index and glycosylated haemoglobin in an Australian cohort

Background

Descriptive norms (what other people do) relate to individual-level dietary behaviour and health outcome including overweight and obesity. Descriptive norms vary across residential areas but the impact of spatial variation in norms on individual-level diet and health is poorly understood. This study assessed spatial associations between local descriptive norms for overweight/obesity and insufficient fruit intake (spatially-specific local prevalence), and individual-level dietary intakes (fruit, vegetable and sugary drinks) and 10-year change in body mass index (BMI) and glycosylated haemoglobin (HbA_1c).

Methods

HbA_1c and BMI were clinically measured three times over 10 years for a population-based adult cohort (n = 4056) in Adelaide, South Australia. Local descriptive norms for both overweight/obesity and insufficient fruit intake specific to each cohort participant were calculated as the prevalence of these factors, constructed from geocoded population surveillance data aggregated for 1600 m road-network buffers centred on cohort participants’ residential addresses. Latent growth models estimated the effect of local descriptive norms on dietary behaviours and change in HbA_1c and BMI, accounting for spatial clustering and covariates (individual-level age, sex, smoking status, employment and education, and area-level median household income).

Results

Local descriptive overweight/obesity norms were associated with individual-level fruit intake (inversely) and sugary drink consumption (positively), and worsening HbA_1c and BMI. Spatially-specific local norms for insufficient fruit intake were associated with individual-level fruit intake (inversely) and sugary drink consumption (positively) and worsening HbA_1c but not change in BMI. Individual-level fruit and vegetable intakes were not associated with change in HbA_1c or BMI. Sugary drink consumption was also not associated with change in HbA_1c but rather with increasing BMI.

Conclusion

Adverse local descriptive norms for overweight/obesity and insufficient fruit intake are associated with unhealthful dietary intakes and worsening HbA_1c and BMI. As such, spatial variation in lifestyle-related norms is an important consideration relevant to the design of population health interventions. Adverse local norms influence health behaviours and outcomes and stand to inhibit the effectiveness of traditional intervention efforts not spatially tailored to local population characteristics. Spatially targeted social de-normalisation strategies for regions with high levels of unhealthful norms may hold promise in concert with individual, environmental and policy intervention approaches.

Influence of Gender on Associations of Obstructive Sleep Apnea Symptoms with Chronic Conditions and Quality of Life

Women are less likely than men to be diagnosed with obstructive sleep apnea (OSA). We examined contemporary gender differences in symptoms, health status, and quality of life associated with diagnosed OSA and OSA symptoms in a population-based sample. A 2015 postal/on-line questionnaire of 2889 active participants of The North West Adelaide Health Study (response rate = 54%, male n = 704; female n = 856; age 30–100 years) assessed previously diagnosed OSA, OSA symptoms, insomnia, doctor-diagnosed medical conditions, and the SF-36. In weighted analyses, self-reported diagnosed OSA (men: 12.6%, n = 95; women: 3.3%, n = 27) and OSA symptoms (men: 17.1%; women: 9.7%) were more common in men. Diagnosed OSA showed stronger adjusted associations with typical OSA features in women, including obesity (women-odds ratio (OR), 95% CI: 5.7, 1.9–17.1, men: 2.2, 1.2–4.0), daytime sleepiness (women: 6.4, 2.7–15.6, men: 3.3, 2.1–5.4), and loud snoring (women: 25.4, 9.4–69.1, men: 8.7, 5.2–14.4). Diagnosed OSA was independently associated with cardiovascular disease (CVD) in men, and in women with high cholesterol, respiratory disease, insomnia, and reduced SF-36 Physical Component Summary score. In both sexes, OSA symptoms were significantly associated with depression, insomnia, and moderate to severe impairments in SF-36 physical and mental component summary scores. Diagnosed women showed clinical characteristics overtly related to OSA. A higher index of clinical suspicion of OSA may be required in women for a condition regarded as male-predominant to increase equity in health outcomes.

Are Perceived and Objective Distances to Fresh Food and Physical Activity Resources Associated with Cardiometabolic Risk?

Perceived and objective measures of neighbourhood features have shown limited correspondence. Few studies have examined whether discordance between objective measures and individual perceptions of neighbourhood environments relates to individual health. Individuals with mismatched perceptions may benefit from initiatives to improve understandings of resource availability. This study utilised data from n = 1491 adult participants in a biomedical cohort to evaluate cross-sectional associations between measures of access (perceived, objective, and perceived-objective mismatch) to fruit and vegetable retailers (FVR) and public open space (POS), and clinically-measured metabolic syndrome and its component risk factors: central obesity, dyslipidaemia, hypertension and pre-diabetes/diabetes. Access measures included perceived distances from home to the nearest FVR and POS, corresponding objectively-assessed road network distances, and the discordance between perceived and objective distances (overestimated (i.e., mismatched) distances versus matched perceived-objective distances). Individual and neighbourhood measures were spatially joined using a geographic information system. Associations were evaluated using multilevel logistic regression, accounting for individual and area-level covariates. Hypertension was positively associated with perceived distances to FVR (odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.02, 1.28) and POS (OR = 1.19, 95% CI = 1.05, 1.34), after accounting for covariates and objective distances. Hypertension was positively associated with overestimating distances to FVR (OR = 1.36, 95% CI = 1.02, 1.80). Overestimating distances to POS was positively associated with both hypertension (OR = 1.42, 95% CI = 1.11, 1.83) and dyslipidaemia (OR = 1.25, 95% CI = 1.00, 1.57). Results provide new evidence for specific associations between perceived and overestimated distances from home to nearby resources and cardiometabolic risk factors.

Frailty prevalence in Australia: Findings from four pooled Australian cohort studies

OBJECTIVE

To examine frailty prevalence in Australian older adults.

METHODS

Frailty was measured using a modified Fried Frailty Phenotype (FFP) in a combined cohort of 8804 Australian adults aged ≥65 years (female 86%, median age 80 (79-82) years) from the Dynamic Analyses to Optimise Ageing Project and the North West Adelaide Health Study.

RESULTS

Using the FFP, 21% of participants were frail while a further 48% were prefrail. Chi-squared testing of frailty among four age groups (65-69, 70-74, 75-79 and 80-84 years) for sex, and marital status revealed that frailty was significantly higher for women (approximately double that of men), increased significantly with advancing age for both sexes, and was significantly higher for women who were widowed, divorced or never married.

CONCLUSION

If frailty could be prevented or reversed, it would have an impact on a larger number of older people.

Frailty prevalence and factors associated with the Frailty Phenotype and Frailty Index: Findings from the North West Adelaide Health Study

OBJECTIVE

To determine the prevalence of frailty and associated factors in the North West Adelaide Health Study (2004-2006) using the Frailty Phenotype (FP) and Frailty Index (FI).

METHODS

Frailty was measured in 909 community-dwelling participants aged ≥65 years using the FP and FI.

RESULTS

The FP classified 18% of participants as frail and the FI 48%. The measures were strongly correlated (r = 0.76, P < 0.001) and had a kappa agreement of 0.38 for frailty classification, with 37% of participants classified as non-frail by the FP being classified as frail by the FI. Being older, a current smoker, and having multimorbidity and polypharmacy were associated with higher frailty levels by both tools. Female, low income, obesity and living alone were associated with the FI.

CONCLUSION

Frailty prevalence was higher when assessed using the FI. Socioeconomic factors and other health determinants contribute to higher frailty levels.

Does Physical Activity Mediate the Associations Between Local-Area Descriptive Norms, Built Environment Walkability, and Glycosylated Hemoglobin?

Associations between local-area residential features and glycosylated hemoglobin (HbA_1c) may be mediated by individual-level health behaviors. Such indirect effects have rarely been tested. This study assessed whether individual-level self-reported physical activity mediated the influence of local-area descriptive norms and objectively expressed walkability on 10-year change in HbA_1c. HbA_1c was assessed three times for adults in a 10-year population-based biomedical cohort (n = 4056). Local-area norms specific to each participant were calculated, aggregating responses from a separate statewide surveillance survey for 1600 m road-network buffers centered on participant addresses (local prevalence of overweight/obesity (body mass index ≥25 kg/m²) and physical inactivity (<150 min/week)). Separate latent growth models estimated direct and indirect (through physical activity) effects of local-area exposures on change in HbA_1c, accounting for spatial clustering and covariates (individual-level age, sex, smoking status, marital status, employment and education, and area-level median household income). HbA_1c worsened over time. Local-area norms directly and indirectly predicted worsening HbA_1c trajectories. Walkability was directly and indirectly protective of worsening HbA_1c. Local-area descriptive norms and walkability influence cardiometabolic risk trajectory through individual-level physical activity. Efforts to reduce population cardiometabolic risk should consider the extent of local-area unhealthful behavioral norms and walkability in tailoring strategies to improve physical activity.

SSRI antidepressant use potentiates weight gain in the context of unhealthy lifestyles: results from a 4-year Australian follow-up study

OBJECTIVE

To examine the association between antidepressant use and weight gain, as well as the interaction with lifestyle factors.

DESIGN

Longitudinal study.

SETTING AND PARTICIPANTS

We used data from 2334 adults from two stages (4.4 years apart) of the North West Adelaide Health Study, including validated diet and lifestyle questionnaires, measured body weight and linked pharmaceutical prescription data.

MAIN OUTCOME MEASURES

Body weight change.

RESULTS

188 (8.1%) participants had a mean annual number of 1-2 antidepressant prescriptions, and 212 (9.1%) had over two prescriptions. The mean annual weight gain was 0.12, 0.18 and 0.28 kg in non-users, low (1-2 prescriptions/year) and high (>2 prescriptions/year) antidepressant users, respectively. In multivariable regression models, antidepressant use was positively associated with weight gain: high antidepressant users gained an extra 0.22 (95% CI 0.00 to 0.44) kg per year. This association was mainly due to selective serotonin reuptake inhibitor (SSRI) use. High SSRI users gained 0.48 (95% CI 0.20 to 0.76) kg more than non-users. There was no association between tricyclic or other antidepressant use and weight gain. The association between SSRI use and weight gain was stronger among those with high intake of Western diet, greater sedentary activity, and who smoked.

CONCLUSIONS

SSRIs use was associated with weight gain in the presence of unhealthy behaviours including Western diet, sedentarism and smoking.

The burden of cancer attributable to modifiable risk factors: the Australian cancer-PAF cohort consortium

PURPOSE

To estimate the Australian cancer burden attributable to lifestyle-related risk factors and their combinations using a novel population attributable fraction (PAF) method that accounts for competing risk of death, risk factor interdependence and statistical uncertainty.

PARTICIPANTS

365 173 adults from seven Australian cohort studies. We linked pooled harmonised individual participant cohort data with population-based cancer and death registries to estimate exposure-cancer and exposure-death associations. Current Australian exposure prevalence was estimated from representative external sources. To illustrate the utility of the new PAF method, we calculated fractions of cancers causally related to body fatness or both tobacco and alcohol consumption avoidable in the next 10 years by risk factor modifications, comparing them with fractions produced by traditional PAF methods.

FINDINGS TO DATE

Over 10 years of follow-up, we observed 27 483 incident cancers and 22 078 deaths. Of cancers related to body fatness (n=9258), 13% (95% CI 11% to 16%) could be avoided if those currently overweight or obese had body mass index of 18.5-24.9 kg/m2. Of cancers causally related to both tobacco and alcohol (n=4283), current or former smoking explains 13% (11% to 16%) and consuming more than two alcoholic drinks per day explains 6% (5% to 8%). The two factors combined explain 16% (13% to 19%): 26% (21% to 30%) in men and 8% (4% to 11%) in women. Corresponding estimates using the traditional PAF method were 20%, 31% and 10%. Our PAF estimates translate to 74 000 avoidable body fatness-related cancers and 40 000 avoidable tobacco- and alcohol-related cancers in Australia over the next 10 years (2017-2026). Traditional PAF methods not accounting for competing risk of death and interdependence of risk factors may overestimate PAFs and avoidable cancers.

FUTURE PLANS

We will rank the most important causal factors and their combinations for a spectrum of cancers and inform cancer control activities.

A comparison of principal component analysis, partial least-squares and reduced-rank regressions in the identification of dietary patterns associated with bone mass in ageing Australians

PURPOSE

The relative advantages of dietary analysis methods, particularly in identifying dietary patterns associated with bone mass, have not been investigated. We evaluated principal component analysis (PCA), partial least-squares (PLS) and reduced-rank regressions (RRR) in determining dietary patterns associated with bone mass.

METHODS

Data from 1182 study participants (45.9% males; aged 50 years and above) from the North West Adelaide Health Study (NWAHS) were used. Dietary data were collected using a food frequency questionnaire (FFQ). Dietary patterns were constructed using PCA, PLS and RRR and compared based on the performance to identify plausible patterns associated with bone mineral density (BMD) and content (BMC).

RESULTS

PCA, PLS and RRR identified two, four and four dietary patterns, respectively. All methods identified similar patterns for the first two factors (factor 1, "prudent" and factor 2, "western" patterns). Three, one and none of the patterns derived by RRR, PLS and PCA were significantly associated with bone mass, respectively. The "prudent" and dairy (factor 3) patterns determined by RRR were positively and significantly associated with BMD and BMC. Vegetables and fruit pattern (factor 4) of PLS and RRR was negatively and significantly associated with BMD and BMC, respectively.

CONCLUSIONS

RRR was found to be more appropriate in identifying more (plausible) dietary patterns that are associated with bone mass than PCA and PLS. Nevertheless, the advantage of RRR over the other two methods (PCA and PLS) should be confirmed in future studies.

The association between gastroesophageal reflux disease with sleep quality, depression, and anxiety in a cohort study of Australian men

BACKGROUND AND AIM

Previous clinical studies have demonstrated a relationship between gastroesophageal reflux disease (GERD) with anxiety and depression; however, few population-based studies have controlled for sleep disorders. The current study aimed to assess the relationship between GERD and anxiety, depression, and sleep disorders in a community-based sample of Australian men.

METHODS

Participants comprised a subset of 1612 men (mean age: 60.7 years, range: 35-80) who participated in the Men Androgen Inflammation Lifestyle Environment and Stress Study during the years 2001-2012, who had complete GERD measures (Gastresophageal Reflux Disease Questionnaire), and were not taking medications known to impact gastrointestinal function (excluding drugs taken for acid-related disorders). Current depression and anxiety were defined by (i) physician diagnosis, (ii) symptoms of depression (Beck Depression Inventory and Centre for Epidemiological Studies Depression Scale) or anxiety (Generalized Anxiety Disorder-7), and/or current depressive or anxiolytic medication use. Previous depression was indicated by past depressive diagnoses/medication use. Data on sleep quality, daytime sleepiness, and obstructive sleep apnea were collected along with several health, lifestyle, and medical factors, and these were systematically evaluated in both univariate and multivariable analyses.

RESULTS

Overall, 13.7% (n = 221) men had clinically significant GERD symptoms. In the adjusted models, an association between GERD and anxiety (odds ratio [OR] 2.7; 95% confidence interval [CI] 1.0-6.8) and poor sleep quality (OR 1.8; 95% CI 1.2-2.9) was observed; however, no effect was observed for current depression (OR 1.5; 95% CI 0.8-2.7). After removing poor sleep quality from the model, an independent association between current depression (OR 2.6; 95% CI 1.7-3.8) and current anxiety (OR 3.2; 95% CI 1.8-6.0) and GERD was observed, but not for previous depression (OR 1.4; 95% CI 0.7-2.8).

CONCLUSION

In this sample of urban-dwelling men, we observed a strong independent association between GERD, anxiety, and current depression, the latter appearing to be partly mediated by poor sleep quality. Patients presenting with GERD should have concurrent mental health assessments in order to identify potential confounders to the successful management of their symptoms.

Identification of Clusters of Foot Pain Location in a Community Sample

OBJECTIVE

To identify foot pain clusters according to pain location in a community-based sample of the general population.

METHODS

This study analyzed data from the North West Adelaide Health Study. Data were obtained between 2004 and 2006, using computer-assisted telephone interviewing, clinical assessment, and self-completed questionnaire. The location of foot pain was assessed using a diagram during the clinical assessment. Hierarchical cluster analysis was undertaken to identify foot pain location clusters, which were then compared in relation to demographics, comorbidities, and podiatry services utilization.

RESULTS

There were 558 participants with foot pain (mean age 54.4 years, 57.5% female). Five clusters were identified: 1 with predominantly arch and ball pain (26.8%), 1 with rearfoot pain (20.9%), 1 with heel pain (13.3%), and 2 with predominantly forefoot, toe, and nail pain (28.3% and 10.7%). Each cluster was distinct in age, sex, and comorbidity profile. Of the two clusters with predominantly forefoot, toe, and nail pain, one of them had a higher proportion of men and those classified as obese, had diabetes mellitus, and used podiatry services (30%), while the other was comprised of a higher proportion of women who were overweight and reported less use of podiatry services (17.5%).

CONCLUSION

Five clusters of foot pain according to pain location were identified, all with distinct age, sex, and comorbidity profiles. These findings may assist in the identification of individuals at risk for developing foot pain and in the development of targeted preventive strategies and treatments.

Local descriptive body weight and dietary norms, food availability, and 10-year change in glycosylated haemoglobin in an Australian population-based biomedical cohort

BACKGROUND

Individual-level health outcomes are shaped by environmental risk conditions. Norms figure prominently in socio-behavioural theories yet spatial variations in health-related norms have rarely been investigated as environmental risk conditions. This study assessed: 1) the contributions of local descriptive norms for overweight/obesity and dietary behaviour to 10-year change in glycosylated haemoglobin (HbA1c), accounting for food resource availability; and 2) whether associations between local descriptive norms and HbA1c were moderated by food resource availability.

METHODS

HbA1c, representing cardiometabolic risk, was measured three times over 10 years for a population-based biomedical cohort of adults in Adelaide, South Australia. Residential environmental exposures were defined using 1600 m participant-centred road-network buffers. Local descriptive norms for overweight/obesity and insufficient fruit intake (proportion of residents with BMI ≥ 25 kg/m2 [n = 1890] or fruit intake of <2 serves/day [n = 1945], respectively) were aggregated from responses to a separate geocoded population survey. Fast-food and healthful food resource availability (counts) were extracted from a retail database. Separate sets of multilevel models included different predictors, one local descriptive norm and either fast-food or healthful food resource availability, with area-level education and individual-level covariates (age, sex, employment status, education, marital status, and smoking status). Interactions between local descriptive norms and food resource availability were tested.

RESULTS

HbA1c concentration rose over time. Local descriptive norms for overweight/obesity and insufficient fruit intake predicted greater rates of increase in HbA1c. Neither fast-food nor healthful food resource availability were associated with change in HbA1c. Greater healthful food resource availability reduced the rate of increase in HbA1c concentration attributed to the overweight/obesity norm.

CONCLUSIONS

Local descriptive health-related norms, not food resource availability, predicted 10-year change in HbA1c. Null findings for food resource availability may reflect a sufficiency or minimum threshold level of resources such that availability poses no barrier to obtaining healthful or unhealthful foods for this region. However, the influence of local descriptive norms varied according to food resource availability in effects on HbA1c. Local descriptive health-related norms have received little attention thus far but are important influences on individual cardiometabolic risk. Further research is needed to explore how local descriptive norms contribute to chronic disease risk and outcomes.

Residential proximity to urban centres, local-area walkability and change in waist circumference among Australian adults

Consistent associations have been observed between macro-level urban sprawl and overweight/obesity, but whether residential proximity to urban centres predicts adiposity change over time has not been established. Further, studies of local-area walkability and overweight/obesity have generated mixed results. This study examined 4-year change in adults' waist circumference in relation to proximity to city centre, proximity to closest suburban centre, and local-area walkability. Data were from adult participants (n=2080) of a cohort study on chronic conditions and health risk factors in Adelaide, Australia. Baseline data were collected in 2000-03 with a follow-up in 2005-06. Multilevel regression models examined in 2015 the independent and joint associations of the three environmental measures with change in waist circumference, accounting for socio-demographic covariates. On average, waist circumference rose by 1.8cm over approximately 4years. Greater distance to city centre was associated with a greater increase in waist circumference. Participants living in distal areas (20km or further from city centre) had a greater increase in waist circumference (mean increase: 2.4cm) compared to those in proximal areas (9km or less, mean increase: 1.2cm). Counterintuitively, living in the vicinity of a suburban centre was associated with a greater increase in adiposity. Local-area walkability was not significantly associated with the outcome. Residential proximity to city centre appears to be protective against excessive increases in waist circumference. Controlled development and targeted interventions in the urban fringe may be needed to tackle obesity. Additional research needs to assess behaviours that mediate relationships between sprawl and obesity.

Association between dietary patterns and low bone mineral density among adults aged 50 years and above: findings from the North West Adelaide Health Study (NWAHS)

Studies on the association between dietary patterns and bone mineral density (BMD) have reported inconsistent findings. Data from the North West Adelaide Health Study, a population-based cohort study undertaken in Australia, were used to assess this association among adults aged 50 years and above. In this specific study, 1182 adults (545 males, 45·9 %) had dietary data collected using a FFQ and also had BMD measurements taken using dual-energy X-ray absorptiometry. Factor analysis with principal component method was applied to ascertain dietary patterns. Two distinct dietary patterns were identified. Pattern 1 ('prudent pattern') was characterised by high intake of fruits, vegetables, sugar, nut-based milk, fish, legumes and high-fibre bread. In contrast, pattern 2 ('Western pattern') was characterised by high levels of processed and red meat, snacks, takeaway foods, jam, beer, soft drinks, white bread, poultry, potato with fat, high-fat dairy products and eggs. Compared with the study participants in the first tertile (T1, lowest consumption) of the prudent pattern, participants in the third tertile (T3) had a lower prevalence of low BMD (prevalence ratio (PR)=0·52; 95 % CI 0·33, 0·83) after adjusting for socio-demographic, lifestyle and behavioural characteristics, chronic conditions and energy intake. Participants in T3 of the Western pattern had a higher prevalence of low BMD (PR=1·68; 95 % CI 1·02, 2·77) compared with those in T1. In contrast to the Western diet, a dietary pattern characterised by high intake of fruits, vegetables and dairy products is positively associated with BMD.

Predictors of foot pain in the community: the North West Adelaide health study

BACKGROUND

Foot pain has been shown to be prevalent across all age groups. The presence of foot pain may reduce mobility and impact on the ability to undertake activities of daily living. The aim of this study was to determine factors that are predictive of foot pain in a community based sample of the general population.

METHODS

This study analysed data from the North West Adelaide Health Study, a cohort study located in the northwestern suburbs of Adelaide, South Australia. Data were obtained between 2004-2006 and 2008-2010, using a self-completed questionnaire, computer assisted telephone interviewing, and a clinical assessment. The sensitivity, specificity and positive predictive values of variables were determined and generalised linear models ascertained the variables associated with the highest relative risk of self-reporting foot pain in 2008-2010 based on the data obtained in 2004-2006.

RESULTS

The prevalence of foot pain in 2004-2006 was 14.9 % (95 % CI 13.6-16.4) and in 2008-2010, 29.9 % (95 % CI 27.5-32.5). Variables with the highest sensitivity were: female sex, ever having back pain, self-reported arthritis, body mass index (BMI) classified as obese and having foot pain in 2004-2006, while most variables demonstrated high specificity. Those with the highest risk of reporting foot pain in 2008-2010 were those with depressive symptoms, self-reported arthritis, high BMI, self-reported upper limb pain and foot pain (in general or in specific regions of the foot) in 2004-2006.

CONCLUSION

Foot pain is common in the general population and those with the greatest risk of foot pain potentially represent a high level of chronicity and potential burden on the health system. Addressing the factors that predict foot pain, as well as the provision of targeted messages to highlight the importance of managing foot pain, may help reduce the impact on the population.

BIRC3 single nucleotide polymorphism associate with asthma susceptibility and the abundance of eosinophils and neutrophils

BACKGROUND AND OBJECTIVE

Aberrant apoptosis is a disease susceptibility mechanism relevant for asthma, whereby fragility of the airway epithelium and enhanced survival of inflammatory cells, contributes to its pathogenesis and prolongation. Cellular Inhibitor of Apoptosis Proteins (cIAP) suppress apoptosis, and participate in the immune response. In this study, single nucleotide polymorphisms (SNP) in the BIRC2 (codes cIAP1) and BIRC3 (cIAP2) genes were evaluated for an association with asthma.

METHODS

Caucasian asthmatic (n = 203) and control (n = 198) subjects were selected from participants in the North West Adelaide Health Study. SNPs (n = 9) spanning the consecutively positioned BIRC2 and BIRC3 genes, were selected using a haplotype tagging approach. Alleles and haplotype associations were analysed by logistic regression, assuming an additive genetic model, and adjusted for gender and atopy.

RESULTS

The frequency of the minor allele for the BIRC3 SNP rs3460 was significantly lower in asthmatics compared to the control cases (P = 0.046). BIRC3 SNPs rs7928663 and rs7127583 associated with a reduction in eosinophil and neutrophil abundance when assessed across the study population (multivariate P values = 0.002, and 0.005, respectively). Further, the frequency of a haplotype tagged by rs3460, rs7928663 and rs7127583 was reduced in the asthma sub group (P = 0.05), while the presence of the major allele for rs7928663 associated with an increased load of circulating eosinophils and neutrophils (multivariate P value = 0.001).

CONCLUSIONS

Polymorphisms in the BIRC3 gene, but not BIRC2, are associated with a protective effect with regards to asthma susceptibility, and a reduced load of inflammatory cells.