Noninvasive electrophysiological differences between women and men: differences in body size not an explanation.

There are numerous sex-related differences in cardiac electrophysiology and arrhythmia propensity but very little knowledge about the reasons. Difference in body size has been proposed as one reason and was tested in this study of >20 cardiac electrophysiology parameters in 319 (158 women) apparently healthy 50- to 64-yr-old subjects from a randomly enrolled population sample, the pilot SCAPIS (Swedish Cardiopulmonary Bioimaging Study), using Frank vectorcardiography. We studied conventional conduction intervals, parameters reflecting electrical heterogeneity (dispersion) in the ventricles, QRS- and T-vector directions, spatial QRS-T angles, and T-vector loop morphology. Body surface area (BSA; 2 methods) and lean body mass (LBM), both estimated from body weight and height, were used as body size parameters. According to multivariable linear regression analysis adjusted for sex, there was no association between electrophysiological parameters and body size apart from QRS duration and QRSarea. In conclusion, most electrophysiological parameters assessed completely noninvasively and showing statistically significant differences between women and men on the group level show no association with BSA or LBM. Scaling (indexing) the electrophysiological parameters for body size parameters is therefore not an option. Consequently, the explanation for the sex-related electrophysiological differences should be sought along other lines.NEW & NOTEWORTHY We sought explanations for sex-related differences in >20 cardiac electrophysiology parameters including conventional conduction intervals in 319 (158 women) apparently healthy 50- to 64-yr-old subjects using Frank vectorcardiography, a novelty. Our hypothesis that body size was partly explanatory for such differences had to be refuted apart from QRS duration and QRSarea. Scaling (indexing) electrophysiological parameters for body size is therefore not an option and explanations for electrophysiological sex-related differences are to be sought elsewhere.

The physical and psychological aspects of quality of life mediates the effect of radiation-induced urgency syndrome on disability pension in gynecological cancer survivors.

BACKGROUND: Radiation-induced fecal urgency syndrome is highly prevalent in gynecological cancer survivors. It is associated with decreased quality of life (QoL) and with disability pension. The literature remains unclear about the mediating role of physical and psychological aspects of QoL in the association between urgency syndrome and disability pension. Identifying the pathways between urgency syndrome and disability pension may help to create effective and timely interventions for increasing QoL and reducing disability pension among gynecological cancer survivors. METHODS: We used patient-reported outcome measures from working-age gynecological cancer survivors (n = 247) and data on their disability pension from the official register. The mediating role of physical and psychological aspects of QoL was studied by utilizing mediation analysis based on the counterfactual framework, appropriate for binary outcome, binary mediator with an exposure-mediator interaction. The total effect (TE) was divided into direct and indirect effects using single mediation analysis. Adjusted relative risks and percentage mediated (95% confidence intervals) were calculated. All statistical tests were two-sided. RESULTS: Urgency syndrome increased the risk of disability pension both directly and indirectly (via QoL). Satisfaction with sleep mediated half of the TE (RR = 2.2 (1.1-4.1)) of urgency syndrome on disability pension. Physical health also mediated a similar proportion of the TE (RR = 2.1 (1.2-3.9)). The proportions mediated were higher for physical aspects of QoL (35%-71%) than for psychological aspects (2%-47%). CONCLUSIONS: The investigated aspects of the self-assessed QoL of gynecological cancer survivors may play a role in these women's continuing work-life. It appears that physical health, satisfaction with sleep, psychological well-being, and other investigated aspects of QoL mediate the urgency syndrome-disability pension association.

Mediating Factors for the Relationship between Stress and Work Ability over Time in Young Adults.

Stress can affect work ability. The aim of this study was to identify how this pathway is mediated over time in young adults. Participants of the Work Ability in Young Adults cohort were selected. A theoretical framework was built, which lead to a statistical model. Selected dimensions of mediators were recovery, work demands affecting private life, feelings of control over private life, and physical activity in leisure time. A quadruple serial mediation model was built with four mediators. The total effect of stress on work ability was -0.3955, 95% CI [-0.4764, -0.3146]. The total indirect effect amounted to 81% with an effect of -0.3182, 95% CI [-0.3750, -0.2642]. The relationship between stress and Work Ability Score five years later in young adults was mediated by stress five years later, work demands affecting private life, feelings of control over private life and feeling well-rested upon waking. These results indicate that work demands affecting private life and feelings of control over private life are important mediators of the relationship between stress and work ability in young adults. A well-balanced relationship between work and private life can counteract the influence of stress on work ability in this age group.

Long-term effect of hand-arm vibration on thermotactile perception thresholds.

BACKGROUND: Occupational exposure to hand-transmitted vibration (HTV) is known to cause neurological symptoms such as numbness, reduced manual dexterity, grip strength and sensory perception. The purpose of this longitudinal study was to compare thermotactile perception thresholds for cold (TPTC) and warmth (TPTW) among vibration exposed manual workers and unexposed white collar workers during a follow-up period of 16 years to elucidate if long-term vibration exposure is related to a change in TPT over time. METHODS: The study group consisted of male workers at a production workshop at which some of them were exposed to HTV. They were investigated in 1992 and followed-up in 2008. All participants were physically examined and performed TPT bilaterally at the middle and distal phalanges of the second finger. Two different vibration exposure dosages were calculated for each individual, i.e. the individual cumulative lifetime dose (mh/s2) or a lifetime 8-h equivalent daily exposure (m/s2). RESULTS: A significant mean threshold difference was found for all subjects of about 4-5 °C and 1-2 °C in TPTW and TPTC, respectively, between follow-up and baseline. No significant mean difference in TPTC between vibration exposed and non-exposed workers at each occasion could be stated to exist. For TPTW a small but significant difference was found for the right index finger only. Age was strongly related to thermotactile perception threshold. The 8-h equivalent exposure level (A (8)) dropped from about 1.3 m/s2 in 1992 to about 0.7 m/s2 in 2008. CONCLUSIONS: A lifetime 8-h equivalent daily exposure to hand-transmitted vibration less than 1.3 m/s2 does not have a significant effect on thermotactile perception. Age, however, has a significant impact on the change of temperature perception thresholds why this covariate has to be considered when using TPT as a tool for health screening.