The sensitivity of 38 heart rate variability measures to the addition of artifact in human and artificial 24‐hr cardiac recordings

Background

Artifact is common in cardiac RR interval data derived from 24‐hr recordings and has a significant impact on heart rate variability (HRV) measures. However, the relative impact of progressively added artifact on a large group of commonly used HRV measures has not been assessed. This study compared the relative sensitivity of 38 commonly used HRV measures to artifact to determine which measures show the most change with increasing increments of artifact. A secondary aim was to ascertain whether short‐term and long‐term HRV measures, as groups, share similarities in their sensitivity to artifact.

Methods

Up to 10% of artifact was added to 20 artificial RR (ARR) files and 20 human cardiac recordings, which had been assessed for artifact by a cardiac technician. The added artifact simulated deletion of RR intervals and insertion of individual short RR intervals. Thirty‐eight HRV measures were calculated for each file. Regression analysis was used to rank the HRV measures according to their sensitivity to artifact as determined by the magnitude of slope.

Results

RMSSD, SDANN, SDNN, RR triangular index and TINN, normalized power and relative power linear measures, and most nonlinear methods examined are most robust to artifact.

Conclusion

Short‐term time domain HRV measures are more sensitive to added artifact than long‐term measures. Absolute power frequency domain measures across all frequency bands are more sensitive than normalized and relative frequency domain measures. Most nonlinear HRV measures assessed were relatively robust to added artifact, with Poincare plot SD1 being most sensitive.

     

The influence of stigma and attitudes on seeking help from a GP for mental health problems

BACKGROUND: Lack of mental health specialists in rural and remote communities suggest that rural communities depend more on general practitioners (GPs) for mental health care. Residents of rural communities are less likely than urban residents to seek help from their GPs for mental health issues. The aim of the current study was to examine whether attitudinal factors including perceived stigma, influenced rural residents seeking help from GPs. METHOD: Help-seeking for psychological issues was retrospectively reported by 300 community residents in rural north-west Victoria. Current distress levels, functional disability, and current or lifetime syndromal disorder were recorded. Attitudes towards seeking professional psychological help, perceptions of stigma about mental illness, and belief in helpfulness of GPs, were also measured. RESULTS: Having a positive attitude towards seeking professional help, and believing that a GP would be helpful, were significant predictors of ever having sought help from a GP for mental health problems. Other independent predictors of help-seeking included having a mood, anxiety or substance use disorder, higher distress levels, and greater functional disability due to physical problems. CONCLUSIONS: Seeking help from a GP for psychological problems was predicted by having a positive attitude towards seeking professional psychological help as well as believing a GP would be helpful in treating psychological problems. Illness variables were also strong predictors of help-seeking behaviour. Contrary to expectations, perceived stigma did not influence help-seeking. The findings of this study highlight the important role of GPs in the treatment of mental health problems in the rural community.     

Understanding suicide in Australian farmers

OBJECTIVE: Male farmers in Australia have an elevated risk of suicide. The aims of this study were to investigate the rate of mental health problems amongst farmers compared with non-farmer rural residents and to investigate what additional factors might contribute to an increased risk of suicide amongst farmers. METHOD: This study used a combination of quantitative and qualitative approaches. First, using self-report questionnaire data, we compared rates of mental health problems (a common correlate of suicide) and a number of personality measures between farmers (n=371) and non-farming rural residents (n=380). In addition, semi-structured interviews with farmers (n=32) were used to gain a richer understanding of how the context of farming and mental health interact. RESULTS: Five key findings emerged from the study. First, in the quantitative study, we found no support for the proposition that farmers experience higher rates of mental health problems than do non-farmer rural residents, but we identified potentially important personality differences between farmers and non-farmers, with levels of conscientiousness being significantly higher amongst farmers and levels of neuroticism being significantly lower. A strong association between maleness and farming was also found. In the qualitative study, participants indicated that farming is an environment in which individuals experienced a range of stressors but have limited capacity to acknowledge or express these. In addition, there appeared to be significant attitudinal barriers to seeking help for those who may have mental health problems, particularly male farmers. CONCLUSION: The elevated rate of suicide amongst farmers does not seem to be simply explained by an elevated rate of mental health problems. Individual personality, gender and community attitudes that limit a person's ability to acknowledge or express mental health problems and seek help for these may be significant risk factors for suicide in farmers.     

Role of media and peers on body change strategies among adult men: Is body size important?

There has been limited previous research that has examined the role of sociocultural influences on body change strategies among adult men. The current study investigated the role of specific types of messages (encouragement, teasing and modelling) from peers and the media on the strategies to change weight among adult men. Differences were evaluated between 526 men aged from 18 to 60 years from three groups (normal weight, overweight and obese) on body image, body change strategies and messages about their body received from peers and the media. Men were primarily drawn from United States, Australia and Europe. Results showed that messages received by men regarding losing weight or increasing muscle size differed according to weight. Body image and media messages were the strongest predictors of losing weight, whereas body image importance and messages from peers were the strongest predictors of increasing muscles. These findings highlight the importance of sociocultural influences on body change strategies among adult males. Copyright © 2010 John Wiley & Sons, Ltd and Eating Disorders Association.