The choice of self-rated health measures matter when predicting mortality: evidence from 10 years follow-up of the Australian longitudinal study of ageing

BACKGROUND Self-rated health (SRH) measures with different wording and reference points are often used as equivalent health indicators in public health surveys estimating health outcomes such as healthy life expectancies and mortality for older adults. Whilst the robust relationship between SRH and mortality is well established, it is not known how comparable different SRH items are in their relationship to mortality over time. We used a dynamic evaluation model to investigate the sensitivity of time-varying SRH measures with different reference points to predict mortality in older adults over time. METHODS We used seven waves of data from the Australian Longitudinal Study of Ageing (1992 to 2004; N = 1733, 52.6% males). Cox regression analysis was used to evaluate the relationship between three time-varying SRH measures (global, age-comparative and self-comparative reference point) with mortality in older adults (65+ years). RESULTS After accounting for other mortality risk factors, poor global SRH ratings increased mortality risk by 2.83 times compared to excellent ratings. In contrast, the mortality relationship with age-comparative and self-comparative SRH was moderated by age, revealing that these comparative SRH measures did not independently predict mortality for adults over 75 years of age in adjusted models. CONCLUSIONS We found that a global measure of SRH not referenced to age or self is the best predictor of mortality, and is the most reliable measure of self-perceived health for longitudinal research and population health estimates of healthy life expectancy in older adults. Findings emphasize that the SRH measures are not equivalent measures of health status.This study was funded by the South Australian Health Commission, the Australian Rotary Health Research Fund, the US National Institute of Health (Grant No. AG 08523-02) and the National Health and Medical Research Council (NHMRC; Grant No.229936). KJA is supported by NHMRC Fellowship No.366756

The relationship between age-stereotypes and health locus of control across adult age-groups

OBJECTIVE: This study integrates healthy ageing and health psychology theories to explore the mechanisms underlying the relationship between health control expectancies and age-attitudes on the process of ageing well. Specifically, the aim of this study is to investigate the relationship between age-stereotypes and health locus of control. DESIGN: A population-based survey of 739 adults aged 20 to 97 years (mean=57.3 years, SD=13.66; 42% female) explored attitudes towards ageing and health attitudes. A path-analytical approach was used to investigate moderating effects of age and gender. RESULTS: Higher age-stereotype endorsement was associated with higher chance (β=2.91, p<.001) and powerful other (β=1.07, p=.012) health expectancies, after controlling for age, gender, education and self-rated health. Significant age and gender interactions were found to influence the relationship between age-stereotypes and internal health locus of control. CONCLUSION: Our findings suggest that the relationship between age-stereotypes and health locus of control dimensions must be considered within the context of age and gender. The findings point to the importance of targeting health promotion and interventions through addressing negative age-attitudes

An Australian survey of cognitive health beliefs, intentions, and behaviours through the adult life course

Objective: Information is required regarding cognitive health beliefs and behaviours from across the life in order to inform the design of interventions to optimise cognitive health and reduce the risk of cognitive impairment. Methods: A survey of Australian adults aged 20-89 was administered via Computer Assisted Telephone Interviewing (CATI) software to respondents recruited by random digit dialling (N = 900). Socio-demographic and self-reported health information was collected to investigate associations with cognitive health responses. Results: Alcohol abuse was nominated by the highest proportion of respondents (34.3%) as detrimental for brain health. Fewer than 5% nominated elevated cholesterol, blood pressure, obesity, poor education, or ageing. The most frequently endorsed protective activity was socialising (70%). Socio-demographic factors predicted responses. Age-group differences were apparent in the proportions nominating alcohol (X2=24.2; p<.001), drugs (X2=56.8; p<.001), smoking (X2=13.1; p=.001), nutrition (X2=20.4; p<.001), and mental activity (X2=12.8; p=.002) as relevant to brain health. Activities undertaken for cognitive benefit also differed by age. Across all ages the perceived benefit of activities was not supported by intentions to undertake activities. Conclusions: Interventions are needed to inform and motivate people across the life-course to undertake behaviours specifically to optimise their cognitive health

Development of the motivation to change lifestyle and health behaviours for dementia risk reduction scale

Background and Aims: It is not yet understood how attitudes concerning dementia risk may affect motivation to change health behaviours and lifestyle. This study was designed to develop a reliable and valid theory-based measure to understand beliefs underpinning the lifestyle and health behavioural changes needed for dementia risk reduction. Methods: 617 participants aged ≥ 50 years completed a theory-based questionnaire, namely, the Motivation to Change Lifestyle and Health Behaviours for Dementia Risk Reduction (MCLHB-DRR) scale. The MCLHB-DRR consists of 53 items, reflecting seven subscales of the Health Belief Model. Results: Confirmatory factor analysis was performed and revealed that a seven-factor solution with 27 items fitted the data (comparative fit index = 0.920, root-mean-square error of approximation = 0.047) better than the original 53 items. Internal reliability (α = 0.608–0.864) and test-retest reliability (α = 0.552–0.776) were moderate to high. Measurement of invariance across gender and age was also demonstrated. Conclusions: These results propose that the MCLHB-DRR is a useful tool in assessing the beliefs and attitudes of males and females aged ≥ 50 years towards dementia risk reduction. This measure can be used in the development and evaluation of interventions aimed at dementia prevention

Correlates of subjective health across the aging lifespan: understanding self-rated health in the oldest old

OBJECTIVES: To examine the determinants of self-rated health (SRH) in different age groups of older adults, including the oldest-old. METHODS: Variables assessing physical health, difficulty with self-care, depressive symptoms and cognitive impairment were pooled and harmonised from three Australian longitudinal studies of ageing (n=5,222). The association of these with SRH was examined in older adults aged 60-64 years, 65-74 years, 75-84 years and 85 years and older. RESULTS: SRH was not associated with cognitive impairment or difficulty with self-care in the oldest-old, and its association with physical health was diminished compared with younger groups. Depression showed a significant relationship in all age groups, conferring an approximately fourfold increase in the likelihood of poorer SRH. DISCUSSION: As old age progresses, self-reports of poor health become most closely related to psychological symptoms. This explains some of the paradoxes of past literature and offers important insights for health professionals working with the oldest-old.National Health and Medical Research Council (NHMRC); Australian Research Council Centre of Excellence in Population Ageing Research (CEPAR

Association of cognitive function with glucose tolerance and trajectories of glucose tolerance over 12 years in the AusDiab study

INTRODUCTION: We investigated the association between glucose tolerance status and trajectories of change in blood glucose, and cognitive function in adults aged 25 to 85. METHODS: The sample (n = 4547) was drawn from a national, population-based cohort study in Australia (AusDiab). Fasting plasma glucose (FPG), glycated haemoglobin (HbA1c) and general health were assessed at 0, 5 and 12 years. Covariates included age, education, body mass index, blood pressure and physical activity. At 12 years, participants completed assessments of memory, processing speed and verbal ability. RESULTS: Known diabetes at baseline was associated with slower processing speed at 12 years in both younger (25–59 years) and older (>60 years) age-groups. After 12 years of follow-up, adults aged < 60 with diabetes at baseline had a mean speed score of 49.17 (SE = 1.09) compared with 52.39 (SE = 0.20) in normals. Among younger males without diagnosed diabetes, reduced memory at 12 years was associated with higher HbA1c at 5 years (β = −0.91, SE = 0.26, p < 0.001). No effects were apparent for females or older males. Adjusting for insulin sensitivity (HOMA-%S) and hs-C reactive protein attenuated these associations, but depression and CVD risk did not. Latent class analysis was used to analyse the associations between trajectories of HbA1C and glucose over 12 years, and cognition. Identified classes were described as 1) normal and stable blood glucose over time (reference), 2) high intercept but stable blood glucose over time, and 3) increasing blood glucose over time. In both young males and females, high stable glucose measures were associated with poorer cognitive function after 12 years. CONCLUSIONS: Those with type 2 diabetes, younger males with high non-diabetic HbA1c, and adults with high stable blood glucose are at increased risk of poorer cognition. The findings reinforce the need for management of diabetes risk factors in midlife.For funding or logistical support, the authors are grateful to the National Health and Medical Research Council (NHMRC grants 233200 and 1007544), the Australian Government Department of Health and Ageing, Abbott Australasia Pty Ltd, Alphapharm Pty Ltd, Amgen Australia, AstraZeneca, Bristol-Myers Squibb, City Health Centre—Diabetes Service—Canberra, Department of Health and Community Services—Northern Territory, Department of Health and Human Services—Tasmania, Department of Health—New South Wales, Department of Health—Western Australia, Department of Health—South Australia, Department of Human Services— Victoria, Diabetes Australia, Diabetes Australia Northern Territory, Eli Lilly Australia, Estate of the Late Edward Wilson, GlaxoSmithKline, Jack Brockhoff Foundation, Janssen-Cilag, Kidney Health Australia, Marian & FH Flack Trust, Menzies Research Institute, Merck Sharp & Dohme, Novartis Pharmaceuticals, Novo Nordisk Pharmaceuticals, Pfizer Pty Ltd, Pratt Foundation, Queensland Health, Roche Diagnostics Australia, Royal Prince Alfred Hospital, Sydney, Sanofi Aventis, sanofi-synthelabo, and the Victorian Government’s OIS Program. KJA is funded by NHMRC Research Fellowship No. 1002560. JES is funded by NHMRC Research Fellowship No. 586623

Cross-national insights into the relationship between wealth and wellbeing: a comparison between Australia, the United States of America and South Korea

The positive relationship between wealth and wellbeing has received considerable attention over the last three decades. However, little is known about how the significance of wealth for the health and wellbeing of older adults may vary across societies. Furthermore, researchers tend to focus mainly on income rather than other aspects of financial resources even though older adults often rely on fixed income, particularly after retirement. Using data from the Household, Income and Labour Dynamics in Australia (HILDA) survey (N=1,431), the Health and Retirement Study (HRS, N=4,687), and the Korean Longitudinal Study of Ageing (KLoSA, N=5,447), this exploratory cross-national study examined the relationship between wealth satisfaction and objective wealth and wellbeing (measured as self-rated health and life satisfaction) among older Australians, Americans and Koreans (50+ years). Regression analyses showed that wealth satisfaction was associated with wellbeing over and above monetary wealth in all three countries. The relationship between monetary wealth and self-rated health was larger for the United States of America (USA) than Australian and Korean samples, while the additional contribution of wealth satisfaction to life satisfaction was larger for the Korean than the Australian and USA samples. These findings are discussed in terms of the cultural and economic differences between these countries, particularly as they affect older persons.This research was funded through a grant. - Sarang Kim was supported by ARC/NHMRC Research Network in Ageing Well, Davina French by NHMRC Project Grant No. 410215 and Kaarin Anstey by NHMRC Research Fellowship No. 366756

A molecular line scan in the Hubble Deep Field North

We present a molecular line scan in the Hubble Deep Field North (HDF-N) that covers the entire 3mm window (79-115 GHz) using the IRAM Plateau de Bure Interferometer. Our CO redshift coverage spans z2. We reach a CO detection limit that is deep enough to detect essentially all z>1 CO lines reported in the literature so far. We have developed and applied different line searching algorithms, resulting in the discovery of 17 line candidates. We estimate that the rate of false positive line detections is ~2/17. We identify optical/NIR counterparts from the deep ancillary database of the HDF-N for seven of these candidates and investigate their available SEDs. Two secure CO detections in our scan are identified with star-forming galaxies at z=1.784 and at z=2.047. These galaxies have colors consistent with the `BzK' color selection and they show relatively bright CO emission compared with galaxies of similar dust continuum luminosity. We also detect two spectral lines in the submillimeter galaxy HDF850.1 at z=5.183. We consider an additional 9 line candidates as high quality. Our observations also provide a deep 3mm continuum map (1-sigma noise level = 8.6 μJy/beam). Via a stacking approach, we find that optical/MIR bright galaxies contribute only to <50% of the SFR density at 1<z<3, unless high dust temperatures are invoked. The present study represents a first, fundamental step towards an unbiased census of molecular gas in `normal' galaxies at high-z, a crucial goal of extragalactic astronomy in the ALMA era

Dust Processing and Grain Growth in Protoplanetary Disks in the Taurus-Auriga Star-Forming Region

Mid-infrared spectra of 65 T Tauri stars (TTS) taken with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope are modeled using dust at two temperatures to probe the radial variation in dust composition in the uppermost layers of protoplanetary disks. Most spectra indicating crystalline silicates require Mg-rich minerals and silica, but a few suggest otherwise. Spectra indicating abundant enstatite at higher temperatures also require crystalline silicates at temperatures lower than those required for spectra showing high abundance of other crystalline silicates. A few spectra show 10 micron complexes of very small equivalent width. They are fit well using abundant crystalline silicates but very few large grains, inconsistent with the expectation that low peak-to-continuum ratio of the 10 micron complex always indicates grain growth. Most spectra in our sample are fit well without using the opacities of large crystalline silicate grains. If large grains grow by agglomeration of submicron grains of all dust types, the amorphous silicate components of these aggregates must typically be more abundant than the crystalline silicate components. Crystalline silicate abundances correlate positively with other such abundances, suggesting that crystalline silicates are processed directly from amorphous silicates and that neither forsterite, enstatite, nor silica are intermediate steps when producing either of the other two. Disks with more dust settling typically have greater crystalline abundances. Large-grain abundance is somewhat correlated with greater settling of disks. The lack of strong correlation is interpreted to mean that settling of large grains is sensitive to individual disk properties. Lower-mass stars have higher abundances of large grains in their inner regions.Comment: 84 pages, 27 figures, submitted to the Astrophysical Journal on 7 November, 200

The interplay between ionized gas and massive stars in the HII galaxy IIZw70: integral field spectroscopy with PMAS

We performed an integral field spectroscopic study for the HII galaxy IIZw70 in order to investigate the interplay between its ionized interstellar medium (ISM) and the massive star formation (SF). Observations were taken in the optical spectral range (3700-6800 A) with the Potsdam Multi-Aperture Spectrophotometer (PMAS) attached to the 3.5 m telescope at CAHA. We created and analysed maps of spatially distributed emission-lines, continuum emission and properties of the ionized ISM (e.g. physical-chemical conditions, dust extinction, kinematics). We investigated the relation of these properties to the spatial distribution and evolutionary stage of the massive stars. For the first time we have detected the presence of Wolf-Rayet (WR) stars in this galaxy. The peak of the ionized gas emission coincides with the location of the WR bump. The region of the galaxy with lower dust extinction corresponds to the region that shows the lowest values of velocity dispersion and radial velocity. The overall picture suggests that the ISM of this region is being disrupted via photoionization and stellar winds, leading to a spatial decoupling between gas+stars and dust clouds. The bulk of dust appears to be located at the boundaries of the region occupied by the probable ionizing cluster. We also found that this region is associated to the nebular emission in HeII4686 and to the intensity maximum of most emission lines. This indicates that the hard ionizing radiation responsible for the HeII4686 nebular emission can be related to the youngest stars. Within $\sim$ 0.4 x 0.3 kpc^2 in the central burst, we derived O/H using direct determinations of Te[OIII]. We found abundances in the range 12+log(O/H)=7.65-8.05, yielding an error-weighted mean of 12+log(O/H)=7.86 $\pm$0.05.Comment: 10 pages, 10 figures, accepted for publication in A&A, minor changes adde