A retrospective study on the effects of illness severity and atrial fibrillation on outcomes in the intensive care unit

Introduction: Atrial fibrillation (AF) is common in patients in the intensive care unit (ICU) and has been associated with worse outcomes. However, it is unclear whether AF itself adds to the risk of death or is merely a marker of illness severity. We aimed to record the incidence and outcomes of all patients with different categories of AF and determine whether AF was an independent predictor of death.<p></p> Methods: This retrospective cohort study was undertaken in the ICU of a tertiary-referral university hospital. Category of AF, sex, C-reactive protein (CRP) level, APACHE II score, predicted hospital mortality and survival outcomes were analysed from 1084 records. Percentages, medians and interquartile ranges were used to describe the sample. Chi-square test and the non-parametric Mann–Whitney U test were used, as appropriate, for statistical analysis. Logistic regression analyses were performed to evaluate the association of AF with death in the ICU adjusting for age, sex, CRP level and APACHE II score.<p></p> Results: Overall, 13.6% of patients developed new-onset AF during their critical illness, while 4.3% had a pre-existing history. The hospital mortality rate was higher in those with AF compared with those without (47.9% vs. 30.9%, p<0.001) and higher in those with newly diagnosed AF compared with those with a prior history (53.1% vs. 31.9%, p=0.012). CRP levels were higher in those with AF (p<0.001) compared with those without and higher in those with newly diagnosed AF compared with those with a prior history (p=0.012). On multivariate logistic regression analysis, only the APACHE II score was found to be an independent predictor of death.<p></p> Conclusion: Despite the higher mortality rate in patients with AF, the APACHE II score was the only independent predictor of death within the ICU. Prospective studies are required to explore the apparently reduced risk of dying among those with a prior history of AF.<p></p&gt

Persistent pain after caesarean section and its association with maternal anxiety and socioeconomic background

Background: Pain, both from the surgical site, and from other sources such as musculoskeletal backache, can persist after caesarean section. In this study of a predominantly socially deprived population we have sought to prospectively examine the association between antenatal maternal anxiety and socioeconomic background and the development of persistent pain of all sources after caesarean section. Methods: Demographic details and an anxiety questionnaire were completed by 205 women before elective caesarean section. On the first postoperative day, pain scores were recorded, and at four months patients were asked to complete a Brief Pain Inventory and an Edinburgh Postnatal Depression Score. Results: Of 205 parturients recruited, 186 records were complete at the hospital admission phase and 98 (52.7%) were complete at the four-month follow-up phase. At recruitment, 15.1% reported pain. At four months 41.8% (95% CI 32.1 to 51.6%) reported pain, of whom pain was a new finding in 35.7% (95% CI 26.2 to 45.2%). Antenatal anxiety was not a significant predictor of severity of new pain at four months (P=0.43 for state anxiety, P=0.52 for trait anxiety). However, four-month pain severity did correlate with social deprivation (P=0.011), postnatal depression (P<0.001) and pain at 24 h (P=0.018). Conclusion: Persistent pain from a variety of sources after caesarean section is common. Our findings do not support the use of antenatal anxiety scoring to predict persistent pain in this setting, but suggest that persistent pain is influenced by acute pain, postnatal depression and socioeconomic deprivation

Preparedness for use of the rapid result HIV self-test by gay men and other men who have sex with men (MSM): a mixed methods exploratory study among MSM and those involved in HIV prevention and care

Objectives: The aim of the study was to explore preparedness for the HIV self-test among men who have sex with men (MSM) and those involved in HIV prevention and care. Methods: A mixed methods exploratory research design was employed, detailing awareness and willingness to use the self-test and the perceived barriers and facilitators to implementation. Quantitative and qualitative data collection and analysis were completed in parallel. Descriptive and inferential analysis of cross-sectional bar-based survey data collected from MSM through a self-completed questionnaire and oral fluid specimen collection (n = 999) was combined with qualitative, thematic, analysis of data collected through 12 expert focus groups (n = 55) consisting of gay men, National Health Service (NHS) staff, community organizations, entrepreneurs and activists. Findings were subsequently combined and assessed for synergies. Results: Among MSM, self-test awareness was moderate (55%). Greater awareness was associated with increased educational attainment [adjusted odds ratio 1.51; 95% confidence interval (CI) 1.00–2.30; P = 0.05] and previous history of sexually transmitted infection (STI) testing (adjusted odds ratio 1.63; 95% CI 1.11–2.39; P = 0.01). Willingness to use the test was high (89%) and associated with meeting sexual partners online (unadjusted odds ratio 1.96; 95% CI 1.31–2.94; P < 0.001). Experts highlighted the overall acceptability of self-testing; it was understood as convenient, discreet, accessible, and with a low burden to services. However, some ambivalence towards self-testing was reported; it could reduce opportunities to engage with wider services, wider health issues and the determinants of risk. Conclusions: Self-testing represents an opportunity to reduce barriers to HIV testing and enhance prevention and access to care. Levels of awareness are moderate but willingness to use is high. Self-testing may amplify health inequalities

Intra-dance variation among waggle runs and the design of efficient protocols for honey bee dance decoding

Noise is universal in information transfer. In animal communication, this presents a challenge not only for intended signal receivers, but also to biologists studying the system. In honey bees, a forager communicates to nestmates the location of an important resource via the waggle dance. This vibrational signal is composed of repeating units (waggle runs) that are then averaged by nestmates to derive a single vector. Manual dance decoding is a powerful tool for studying bee foraging ecology, although the process is time-consuming: a forager may repeat the waggle run 1- >100 times within a dance. It is impractical to decode all of these to obtain the vector; however, intra-dance waggle runs vary, so it is important to decode enough to obtain a good average. Here we examine the variation among waggle runs made by foraging bees to devise a method of dance decoding. The first and last waggle runs within a dance are significantly more variable than the middle run. There was no trend in variation for the middle waggle runs. We recommend that any four consecutive waggle runs, not including the first and last runs, may be decoded, and we show that this methodology is suitable by demonstrating the goodness-of-fit between the decoded vectors from our subsamples with the vectors from the entire dances

A retrospective study on the effects of illness severity and atrial fibrillation on outcomes in the intensive care unit

Introduction: Atrial fibrillation (AF) is common in patients in the intensive care unit (ICU) and has been associated with worse outcomes. However, it is unclear whether AF itself adds to the risk of death or is merely a marker of illness severity. We aimed to record the incidence and outcomes of all patients with different categories of AF and determine whether AF was an independent predictor of death.<p></p> Methods: This retrospective cohort study was undertaken in the ICU of a tertiary-referral university hospital. Category of AF, sex, C-reactive protein (CRP) level, APACHE II score, predicted hospital mortality and survival outcomes were analysed from 1084 records. Percentages, medians and interquartile ranges were used to describe the sample. Chi-square test and the non-parametric Mann–Whitney U test were used, as appropriate, for statistical analysis. Logistic regression analyses were performed to evaluate the association of AF with death in the ICU adjusting for age, sex, CRP level and APACHE II score.<p></p> Results: Overall, 13.6% of patients developed new-onset AF during their critical illness, while 4.3% had a pre-existing history. The hospital mortality rate was higher in those with AF compared with those without (47.9% vs. 30.9%, p<0.001) and higher in those with newly diagnosed AF compared with those with a prior history (53.1% vs. 31.9%, p=0.012). CRP levels were higher in those with AF (p<0.001) compared with those without and higher in those with newly diagnosed AF compared with those with a prior history (p=0.012). On multivariate logistic regression analysis, only the APACHE II score was found to be an independent predictor of death.<p></p> Conclusion: Despite the higher mortality rate in patients with AF, the APACHE II score was the only independent predictor of death within the ICU. Prospective studies are required to explore the apparently reduced risk of dying among those with a prior history of AF.<p></p&gt

Demographic, behavioural and anthropometric correlates of food liking: A cross‐sectional analysis of young adults

The degree to which foods are liked or disliked is associated with dietary intake and health behaviours. However, most food liking research has focused on single foods and nutrients and few studies have examined associations with demographics and health behaviours. Thus, this study aimed to investigate the association between food liking and socio‐demographics, health behaviours, diet quality and body mass index (BMI) in a sample of young Australian adults. Data from 1728 undergraduate students (21.8 (standard deviation [SD] 6.0) years; 76% female) were used. Food liking scores and a diet quality index (Dietary Guideline Index, DGI) were estimated from a Food Liking Questionnaire and Food Frequency Questionnaire (FFQ), respectively. Multivariate linear regression analyses were used to assess the association between food liking and correlates. Young adults with higher liking for encouraged core foods were older, female, did their own food shopping, consumed less packaged foods and had better diet quality. Higher liking for discretionary foods and beverages was associated with less healthy behaviours, such as smoking, higher BMI and lower diet quality. These results suggest that food liking measures may offer an appropriate methodology for understanding influences on young adults’ food choices, adding to the body of literature investigating the potential for food liking scores to assess diet–disease relationships

The impact of parental contact upon cortical noxious-related activity in human neonates

BACKGROUND: Neonates display strong behavioural, physiological and cortical responses to tissue-damaging procedures. Parental contact can successfully regulate general behavioural and physiological reactivity of the infant, but it is not known whether it can influence noxious-related activity in the brain. Brain activity is highly dependent upon maternal presence in animal models, and therefore this could be an important contextual factor in human infant pain-related brain activity. METHODS: Global topographic analysis was used to identify the presence and inter-group differences in noxious-related activity in three separate parental contexts. EEG was recorded during a clinically required heel lance in three age and sex-matched groups of neonates (a) while held by a parent in skin-to-skin (n = 9), (b) while held by a parent with clothing (n = 9) or (c) not held at all, but in individualized care (n = 9). RESULTS: The lance elicited a sequence of 4-5 event-related potentials (ERPs), including the noxious ERP (nERP), which was smallest for infants held skin-to-skin and largest for infants held with clothing (p=0.016). The nERP was then followed by additional and divergent long-latency ERPs (> 750 ms post-lance), not previously described, in each of the groups, suggesting the engagement of different higher level cortical processes depending on parental contact. CONCLUSIONS: These results show the importance of considering contextual factors in determining infant brain activity and reveal the powerful influence of parental contact upon noxious-related activity across the developing human brain. SIGNIFICANCE: This observational study found that the way in which the neonatal brain processes a noxious stimulus is altered by the type of contact the infant has with their mother. Specifically, being held in skin-to-skin reduces the magnitude of noxious-related cortical activity. This work has also shown that different neural mechanisms are engaged depending on the mother/infant context, suggesting maternal contact can change how a baby's brain processes a noxious stimulus

Billiard Systems in Three Dimensions: The Boundary Integral Equation and the Trace Formula

We derive semiclassical contributions of periodic orbits from a boundary integral equation for three-dimensional billiard systems. We use an iterative method that keeps track of the composition of the stability matrix and the Maslov index as an orbit is traversed. Results are given for isolated periodic orbits and rotationally invariant families of periodic orbits in axially symmetric billiard systems. A practical method for determining the stability matrix and the Maslov index is described.Comment: LaTeX, 19 page

Semiclassical Treatment of Diffraction in Billiard Systems with a Flux Line

In billiard systems with a flux line semiclassical approximations for the density of states contain contributions from periodic orbits as well as from diffractive orbits that are scattered on the flux line. We derive a semiclassical approximation for diffractive orbits that are scattered once on a flux line. This approximation is uniformly valid for all scattering angles. The diffractive contributions are necessary in order that semiclassical approximations are continuous if the position of the flux line is changed.Comment: LaTeX, 17 pages, 4 figure