Lauren Krnjacki

International epidemiology of prostate cancer: Geographical distribution and secular trends

This review outlines current international patterns in prostate cancer incidence and mortality rates and survival, including recent trends and a discussion of the possible impact of prostate-specific antigen (PSA) testing on the observed data. Internationally, prostate cancer is the second most common cancer diagnosed among men (behind lung cancer), and is the sixth most common cause of cancer death among men. Prostate cancer is particularly prevalent in developed countries such as the United States and the Scandinavian countries, with about a six-fold difference between high-incidence and low-incidence countries. Interpretation of trends in incidence and survival are complicated by the increasing impact of PSA testing, particularly in more developed countries. As Western influences become more pronounced in less developed countries, prostate cancer incidence rates in those countries are tending to increase, even though the prevalence of PSA testing is relatively low. Larger proportions of younger men are being diagnosed with prostate cancer and living longer following diagnosis of prostate cancer, which has many implications for health systems. Decreasing mortality rates are becoming widespread among more developed countries, although it is not clear whether this is due to earlier diagnosis (PSA testing), improved treatment, or some combination of these or other factors.

Intersections between disability, type of impairment, gender and socio-economic disadvantage in a nationally representative sample of 33,101 working-aged Australians

BACKGROUND People with disabilities are socio-economically disadvantaged and have poorer health than people without disabilities; however, little is known about the way in which disadvantage is patterned by gender and type of impairment. OBJECTIVES 1. To describe whether socio-economic circumstances vary according to type of impairment (sensory and speech, intellectual, physical, psychological and acquired brain injury). 2. To compare levels of socio-economic disadvantage for women and men with the same impairment type. METHODS We used a large population-based disability-focused survey of Australians, analyzing data from 33,101 participants aged 25-64. Indicators of socio-economic disadvantage included education, income, employment, housing vulnerability, and multiple disadvantage. Stratified by impairment type, we estimated: the population weighted prevalence of socio-economic disadvantage; the relative odds of disadvantage compared to people without disabilities; and the relative odds of disadvantage between women and men. RESULTS With few exceptions, people with disabilities fared worse for every indicator compared to people without disability; those with intellectual and psychological impairments and acquired brain injuries were most disadvantaged. While overall women with disabilities were more disadvantaged than men, the magnitude of the relative differences was lower than the same comparisons between women and men without disabilities, and there were few differences between women and men with the same impairment types. CONCLUSIONS Crude comparisons between people with and without disabilities obscure how disadvantage is patterned according to impairment type and gender. The results emphasize the need to unpack how gender and disability intersect to shape socio-economic disadvantage.

Psychosocial working conditions in a representative sample of working Australians 2001–2008: an analysis of changes in inequalities over time

Background A number of widely prevalent job stressors have been identified as modifiable risk factors for common mental and physical illnesses such as depression and cardiovascular disease, yet there has been relatively little study of population trends in exposure to job stressors over time. The aims of this paper were to assess: (1) overall time trends in job control and security and (2) whether disparities by sex, age, skill level and employment arrangement were changing over time in the Australian working population. Methods Job control and security were measured in eight annual waves (2000–2008) from the Australian nationally-representative Household Income and Labour Dynamics of Australia panel survey (n=13 188 unique individuals for control and n=13 182 for security). Observed and model-predicted time trends were generated. Models were generated using population-averaged longitudinal linear regression, with year fitted categorically. Changes in disparities over time by sex, age group, skill level and employment arrangement were tested as interactions between each of these stratifying variables and time. Results While significant disparities persisted for disadvantaged compared with advantaged groups, results suggested that inequalities in job control narrowed among young workers compared with older groups and for casual, fixed-term and self-employed compared with permanent workers. A slight narrowing of disparities over time in job security was noted for gender, age, employment arrangement and occupational skill level. Conclusions Despite the favourable findings of small reductions in disparities in job control and security, significant cross-sectional disparities persist. Policy and practice intervention to improve psychosocial working conditions for disadvantaged groups could reduce these persisting disparities and associated illness burdens.

Time trends in socio-economic inequalities for women and men with disabilities in Australia: evidence of persisting inequalities

IntroductionThe socio-economic circumstances and health of people with disabilities has been relatively ignored in public health research, policy and practice in Australia and internationally. This is despite emerging evidence that the socio-economic circumstances that people with disabilities live in contributes to their poorer health. Compared to other developed countries, Australians with disabilities are more likely to live in disadvantaged circumstances, despite being an economically prosperous country; it is therefore likely that the socio-economic disadvantage experienced by Australians with disabilities makes a significant contribution to their health. Despite the importance of this issue Australia does not routinely monitor the socio-economic inequalities for people with disabilities. This paper addresses this gap by describing time trends in socio-economic conditions for Australians with and without disabilities according to the severity of the disability and sex.MethodsCross-sectional analyses of the Australian Bureau of Statistics Survey of Disability, Ageing and Carers were carried out at three time points (1998, 2003 and 2009) to estimate the proportions of women and men (aged between 25 and 64 years) who were living on low incomes, had not completed year 12, were not in paid work, living in private rental and experiencing multiple disadvantage (three or more of the indicators).ResultsPeople with disabilities are less likely to have completed year 12, be in paid work and are more likely to be living on low incomes and experiencing multiple disadvantage. These conditions worsened with increasing severity of disability and increased or persisted over time, with most of the increase between 1998 and 2003. While women with milder disabilities tended to fare worse than men, the proportions were similar for those with moderate and severe/profound disabilities.ConclusionPeople with disabilities experience high levels of socio-economic disadvantage which has increased or persisted over time and these are likely to translate into poorer health outcomes. A large proportion experience multiple forms of disadvantage, reinforcing the need to tackle disadvantage in a coordinated way across sectors.People with disabilities should be a priority population group for public health. Monitoring socio-economic conditions of people with disabilities is critical for informing policy and assessing the impact of disability reforms.

The role of social support in protecting mental health when employed and unemployed: A longitudinal fixed-effects analysis using 12 annual waves of the HILDA cohort

Perceived social support is associated with overall better mental health. There is also evidence that unemployed workers with higher social support cope better psychologically than those without such support. However, there has been limited research about the effect of social support among people who have experienced both unemployment and employment. We assessed this topic using 12 years of annually collected cohort data. The sample included 3190 people who had experienced both unemployment and employment. We used longitudinal fixed-effects modelling to investigate within-person changes in mental health comparing the role of social support when a person was unemployed to when they were employed. Compared to when a person reported low social support, a change to medium (6.35, 95% 5.66 to 7.04, p < 0.001) or high social support (11.58, 95%, 95% CI 10.81 to 12.36, p < 0.001) was associated with a large increase in mental health (measured on an 100 point scale, with higher scores representing better mental health). When a person was unemployed but had high levels of social support, their mental health was 2.89 points (95% CI 1.67 to 4.11, p < 0.001) higher than when they were employed but had lower social support. The buffering effect of social support was confirmed in stratified analysis. There was a strong direct effect of social support on mental health. The magnitude of these differences could be considered clinically meaningful. Our results also suggest that social support has a significant buffering effect on mental health when a person is unemployed.

A Longitudinal Analysis of Changes in Job Control and Mental Health

Deteriorating job control has been previously shown to predict poor mental health. The impact of improvement in job control on mental health is less well understood, yet it is of policy significance. We used fixed-effects longitudinal regression models to analyze 10 annual waves of data from a large Australian panel survey (2001-2010) to test within-person associations between change in self-reported job control and corresponding change in mental health as measured by the Mental Component Summary score of Short Form 36. We found evidence of a graded relationship; with each quintile increase in job control experienced by an individual, the persons mental health increased. The biggest improvement was a 1.55-point increase in mental health (95% confidence interval: 1.25, 1.84) for people moving from the lowest (worst) quintile of job control to the highest. Separate analyses of each of the component subscales of job control-decision authority and skill discretion-showed results consistent with those of the main analysis; both were significantly associated with mental health in the same direction, with a stronger association for decision authority. We conclude that as peoples level of job control increased, so did their mental health, supporting the value of targeting improvements in job control through policy and practice interventions.

Reliability of collecting colorectal cancer stage information from pathology reports and general practitioners in Queensland

Objective: To investigate the reliability of collecting colorectal stage information from pathology reports and general practitioners in Queensland, Australia.

Prevalence and risk of violence against people with and without disabilities: findings from an Australian population-based study

Objectives: There are no population‐based estimates of the prevalence of interpersonal violence among people with disabilities in Australia. The project aimed to: 1) estimate the prevalence of violence for men and women according to disability status; 2) compare the risk of violence among women and men with disabilities to their same‐sex non‐disabled counterparts and; 3) compare the risk of violence between women and men with disabilities.

Mental Health Following Acquisition of Disability in Adulthood--The Impact of Wealth.

Background Acquisition of a disability in adulthood has been associated with a reduction in mental health. We tested the hypothesis that low wealth prior to disability acquisition is associated with a greater deterioration in mental health than for people with high wealth. Methods We assess whether level of wealth prior to disability acquisition modifies this association using 12 waves of data (2001–2012) from the Household, Income and Labour Dynamics in Australia survey–a population-based cohort study of working-age Australians. Eligible participants reported at least two consecutive waves of disability preceded by at least two consecutive waves without disability (1977 participants, 13,518 observations). Fixed-effects linear regression was conducted with a product term between wealth prior to disability (in tertiles) and disability acquisition with the mental health component score of the SF–36 as the outcome. Results In models adjusted for time-varying confounders, there was evidence of negative effect measure modification by prior wealth of the association between disability acquisition and mental health (interaction term for lowest wealth tertile: -2.2 points, 95% CI -3.1 points, -1.2, p<0.001); low wealth was associated with a greater decline in mental health following disability acquisition (-3.3 points, 95% CI -4.0, -2.5) than high wealth (-1.1 points, 95% CI -1.7, -0.5). Conclusion The findings suggest that low wealth prior to disability acquisition in adulthood results in a greater deterioration in mental health than among those with high wealth.

Age and gender differences in the influence of social support on mental health: a longitudinal fixed-effects analysis using 13 annual waves of the HILDA cohort

OBJECTIVES Perceived social support is associated with better mental health. There has been limited attention to how these relationships are modified by age and gender. We assessed this topic using 13 years of cohort data. STUDY DESIGN Prospective cohort study. METHODS The outcome was the Mental Health Inventory-5 (MHI-5), a reliable and valid screening instrument for mood disorders. The main exposure was a social support scale composed of 10 items. We used longitudinal fixed-effects regression modelling to investigate within-person changes in mental health. Analytic models controlled for within-person sources of bias. We controlled for time-related factors by including them into regression modelling. RESULTS The provision of higher levels of social support was associated with greater improvements in mental health for people aged under 30 years than for older age groups. The mental health of females appeared to benefit slightly more from higher levels of social support than males. Improvements in the MHI-5 were on a scale that could be considered clinically significant. CONCLUSIONS The benefits of social support for young people may be connected to age-related transitions in self-identity and peer friendship networks. Results for females may reflect their tendency to place greater emphasis on social networks than males.