Early life stress and child temperament style as predictors of childhood anxiety and depressive symptoms : findings from the longitudinal study of Australian children

Objective. The purpose of this study was to determine whether the relationship between stressful infant environments and later childhood anxiety and depressive symptoms varies as a function of individual differences in temperament style.

Methods. Data was drawn fromthe Longitudinal Study of Australian Children (LSAC). This study examined 3425 infants assessed at three time points, at 1-year, at 2/3 years and at 4/5 years. Temperament was measured using a 12-item version of Toddler Temperament Scale (TTS) and was scored for reactive, avoidant, and impulsive dimensions. Logistic regression was used to model direct relationships and additive interactions between early life stress, temperament, and emotional symptoms at 4 years of age. Analyses were adjusted for socioeconomic status, parental education, andmarital status.

Results. Stressful family environments experienced in the infant’s first year of life (high versus low) and high reactive, avoidant, and impulsive temperament styles directly and independently predicted anxiety and depressive problems in children at 4 years of age. There was no evidence of interaction between temperament and family stress exposure.

Conclusions. Both infant temperament and stress exposures are independent and notable predictors of later anxiety and depressive problems in childhood. The risk relationship between stress exposure in infancy and childhood emotion problems did not vary as a function of infant temperament. Implications for preventive intervention and future research directions are discussed.

Special interests and mental health in autism spectrum disorders

Special interests (SIs) in autism spectrum disorders are a prevalent though relatively under-researched phenomenon. There was partial support for the hypotheses and factors influencing the relationship between SIs and mental health were identified. Findings contribute to a better understanding of SIs including their importance for individuals with ASD.

Training patterns and negative health outcomes in triathlon : longitudinal observations across a full competitive season

AIM: Despite heavy training requirements, triathlon is a sport that is rapidly increasing in popularity. Yet, there is limited research detailing the relationship between training, the incidence of injuries and illness, psychological stress, overtraining and athlete burnout amongst triathletes. Six hypotheses relating inter-individual differences to training factors were generated to evaluate change in self-reported measures of these negative health outcomes over a training year.

METHODS: Thirty, well-trained, triathletes (males n=20: age=27.1±9.1 years and females n=10: age=27.4±6.6 years) from a local triathlon club participated in this study. The study commenced during pre-season training, and involved weekly monitoring of each athlete until the end of the competitive season 45 weeks later. Linear Mixed Modelling was used for the analysis.

RESULTS: Signs and symptoms of injury and illness (SAS) were significantly associated with increases in training factors (P≤0.05); however, greatest impact on SAS was produced by psychological stressors (P≤0.001). Common symptoms of overtraining were significantly affected by increases in exposure to both training and psychological stressors (P≤0.05). Mood disturbance was not significantly affected by training factors (P>0.05) but rather increases in psychological stressors (P≤0.001). Finally, each of the three athlete burnout subscales were significantly affected by both psychological (P≤0.001) stressors as well as varying combinations of training factors (P≤0.05).

CONCLUSIONS: Exposure to stressors (either training or psychological) had significant effects on all negative health outcomes assessed.

Genetics and public health - evolution, or revolution?

During the 19th and early 20th century, public health and genetics shared common ground through similar approaches to health promotion in the population. By the mid-20th century there was a division between public health and genetics, with eugenicists estranged and clinical genetics focused on single gene disorders, usually only relevant to small numbers of people. Now through a common interest in the aetiology of complex diseases such as heart disease and cancer, there is a need for people working in public health and genetics to collaborate. This is not a comfortable convergence for many, particularly those in public health. Nine main concerns are reviewed: fear of eugenics; genetic reductionism; predictive power of genes; non-modifiable risk factors; rights of individuals compared with populations; resource allocation; commercial imperative; discrimination; and understanding and education. This paper aims to contribute to the thinking and discussion about an evolutionary, multidisciplinary approach to understanding, preventing, and treating complex diseases.

Breastfeeding mothers consume more vegetables and a greater variety of fruits and vegetables than non-breastfeeding peers : the influence of socioeconomic position

Aim:  This study compared the diets of breastfeeding and non-breastfeeding mothers from socioeconomically diverse regions of Melbourne to determine whether breastfeeding is a marker for healthier maternal dietary intakes.

Methods:  This cross-sectional study obtained information via self-reported questionnaire from 529 first-time Melbourne mothers. Breastfeeding status was determined when the children were 3.9 months. Diet information was obtained using a validated Food Frequency Questionnaire. Maternal diet was assessed by seven indicators: average daily intake of fruit, vegetables, non-core drinks, non-core sweet snacks, non-core savoury snacks, variety of fruit and variety of vegetables eaten in the preceding 12 months. Associations between breastfeeding status and each dietary variable were assessed using linear regression analyses. Socioeconomic position, maternal body mass index and the cluster-based sampling design were controlled for.

Results:  Of the 529 subjects, 70% were breastfeeding their child. Compared with non-breastfeeding mothers, breastfeeding mothers were found to consume more serves of vegetables (P= 0.001), a greater variety of fruit and vegetables (P= 0.001 and P≤ 0.001 respectively), and sweet snacks were consumed more frequently (P= 0.006). Differences were observed between low and high socioeconomic position mothers for fruit serves (P= 0.003), vegetable serves (P= 0.010) and fruit variety (P= 0.006). These associations persisted after controlling for socioeconomic position and maternal body mass index.

Conclusions:  The association between infant feeding (breastfeeding) and some aspects of maternal diet provides further evidence suggesting a link between maternal and child diets from a younger age than previously examined.

Physical inactivity and other health risks among Australian males in less-skilled occupations

Male workers in less-skilled occupations have higher rates of cardiovascular disease, compared with higher-skilled workers. A representative population sample of Australian male workers was used to compare physical activity levels and selected cardiovascular disease risk factors in less-skilled versus professional and skilled workers. Workers in the less-skilled occupational categories reported significantly more vigorous work and home-based activity than did those in the professional and skilled categories. In multivariate comparisons, cigarette smoking was the only factor that discriminated between the less-skilled versus the professional and skilled employees. Although worksites can potentially provide health-promoting physical activity options for higher-risk groups, our findings suggest that smoking and possibly overweight are risk factors that are more strongly present in less-skilled occupations.

Impact of depression treatment on mental and physical health-related quality of life of cardiac patients : a meta-analysis

PURPOSE: To conduct a meta-analysis evaluating the effectiveness of depression treatment on mental and physical health-related quality of life (HRQOL) of cardiac patients.

METHODS: Studies were identified using medical, health, psychiatry, psychology, and social sciences databases. Inclusion criteria were (1) 1 or more control conditions, (2) random assignment to condition after admission for myocardial infarction (MI)/acute coronary syndrome, after recording positive results on a depression screener, (3) documentation of depression symptoms at baseline, (4) depression management as a component of the rehabilitation/intervention, (5) validated measure of HRQOL as an outcome, at minimum 6-month followup. For meta-analysis, mental and physical HRQOL were the end points studied, using standardized mean differences for continuous outcome measures, with 95% confidence intervals. Heterogeneity was explored by calculating I2 statistic.

RESULTS: Five randomized controlled trials included in the analysis represented 2105 participants (1058 intervention vs 1047 comparator). Compared with a comparator group at 6 months, a test for overall effect demonstrated statistically significant improvements in mental HRQOL in favor of the intervention (standardized mean differences = −0.29 [−0.38 to −0.20], [P < .00001]; I2 = 0%). Depression treatment had a modest yet significant impact on physical HRQOL (standardized mean differences = −0.14 [−0.24 to −0.04] [P = .009]; I2 = 15%).

CONCLUSION: While the impact of post-MI depression interventions on physical HRQOL is modest, treatment can improve mental HRQOL in a significant way. Future research is required to develop and evaluate a program that can achieve vital improvements in overall HRQOL, and potentially cardiovascular outcomes, of cardiac patients.